# Aluminum powder



## degarb (Dec 6, 2016)

Years ago I bought arctic epoxy. Found it gone after half a build. Not very good thermally, probably as good as expected. Researching it was not silver, but aluminum. . I tried zinc oxide, but table shows not good thermal conductor. . Copper is 2x of aluminum, a aluminum, I recall. . However, bought copper powder, while I proved good thermally, still too expensive to be practical. 

So, I bought bag of aluminum powder. But on arrival, thoughts of its danger arose. . I am first researching before opening. . So far, I might keep in a sealed zip lock bag, inside a plastic jar, inside a giant pickle jar, whose lid is rustproofed and outsides padded. And kept in detached garage. . Mixing into epoxy outside only. . I already use all the stuff of any meth maker for my work, so why not get into the terrorists tools?

Though I suspect this powder isn't suitable for termite, as you need a certain granular shape to catch more oxygen. 

I hate to sign up and post in a fireworks forum for one storage question. 

I have no nitrogen to dump on top.

Overall, it looks no more flammable or explosive than sawdust. . Yet when it goes, fire super hot and unstoppable. . Probably too dust finer and will hang in air longer. . If not still creepier.


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## Obijuan Kenobe (Dec 6, 2016)

Magnesium powder might be scary (still need to light it with something hot), but I don't think you need to worry about Al powder. It won't spontaneously combust or anything.

obi


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## HarryN (Dec 6, 2016)

Just store it in an empty metal paint bucket of sand or baking soda / baking powder. If it starts to get hot, baking soda (or better the powder) will release CO2 and slow it down. Sand is commonly used to put out metal and Li battery fires, not as good as the purpose built agents, but fairly decent.

In fact, a lot of R/C hobby people will charge their batteries in a bucket of sand to keep things contained "just in case". It is good, cheap insurance.

New, empty metal paint buckets are sold at places like HD / Lowes. Applying a label is easy.

Especially during the holidays when there is a lot more complex cooking, wiring, candles, etc. around, keeping some things like cat litter, sand, baking soda, and / or fire extinguishers to quickly knock down a small fire is a good idea.


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## scianiac (Dec 9, 2016)

I would be most concerned when handling it to avoid static discharge, probably still not that much of a risk but can't be too safe. Have you considered silicon carbide? I've used it quite a bit as a thermal filler. It's relatively cheap, safe (just don't inhale it of course), non conductive so can be used for things like potting, and can easily be purchased in a wide range of meshs. Depending if you are trying fill a very small gap or a larger one you can mix in different meshs. So large particles mixed with smaller ones to fill in the spaces between the large ones are always best as long as the gap you are filling isn't too small so the larger particles add extra distance. The actual thermal conductivity is based on the crystal structure of which there are many for silicone carbide. For example 3C is 360WmK while 6H is 490WmK. 6H (alpha) is the most common so I think that's what most abrasives are made from. I can only imagine it's not used in commercial products because it would be murder on the processing equipment for little gain over other options.


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## degarb (Dec 11, 2016)

Is silicon carbide sold by a sand blasting supply? 

2 years ago, I bought a 50 lb bag of blasting soda. . I vaguely recall 30 bucks. . Similar to sodium bicarbonate. I personally didn't test flame fighting. But I filled up one 5 gallon pail and a half dozen clear peanut jars for around the house. My teen girl is stupidly allowed candles an insense in her room. . Not allowed to go for walks in woods alone; but, endangering lives of entire family as they sleep, is fine with the wife. . My teen reported the blasting soda did put out one fire in her room. . Wife, though, hides the extinguishers at every opportunity, as they don't go with the decor. . Easier to comply with wife than risk certain divorce court. . I need an artful, artistist fire extinguisher worthy of HGTV, and many designs, as she will grow tired every 6 months, move the furniture around and put the old artful extinguishers in the basement. 

Anyway.... Sourcing and chemical similarity of blasting soda. 
: am I on right track? . Or is blasting soda not good or half the price elsewhere?

I could mix some left over blasting sand, with my blasting soda, to leave enough soda for any new artistic fire containers I might one day hit upon. This would cost me little... 
Unfortunately, to my mind and eye, the more practical the design, the more solutions to problems it solves, the more beautiful. While to most architects and designers, it is the opposite. . (My stomach turns when flipping past Project runway, or my local art museum whose building is a monstrous poor, useless design - unless wasting money and fighting roof leaks and wind storms is your goal.) 

In my metal paint can, maybe I should break the pound into many small zip locks. In case on were to ignite during opening, it would be harder to ignite the rest.


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## degarb (Dec 11, 2016)

I was water sand blasting old rusty iron railings, the spring before last. I started out using the black diamond. . I switched to landscaping sand (their purer form that I strained), as it worked just as well and cost far, far less, and didn't require a 55 minute round trip to outside the city. . My bet is that the black diamond was true silicon carbide. 

I have two left over fives of the sand in my storage, which I would love to put to good use. Home depot Kinda rips people on sand. . Toys r us is more reasonable, as I recall. I just got lucky having a contractor only landscape supply practically across the road.


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## degarb (Dec 11, 2016)

Hmmm http://m.harborfreight.com/50-lbs-m...a-65929.html?utm_referrer=direct/not provided


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## scianiac (Dec 11, 2016)

I don't think any of those are silicon carbide. The black diamond I'm guessing is coal slag, a common blasting media that is more gentle than sand if I recall. And the soda is just baking soda. Neither would be a good choice thermal wise. Also of course be careful when blasting with regular sand, that's how you get silicosis, which is one of the reasons while blasting soda, slag, glass beads, etc are replacing regular sand. I bought my silicon carbide on ebay. I got some 600grit and some 120/240grit. For potting drivers I use a mix of the two to get optimal packing, for closer tolerance joints I just use the 600. I don't think it's a very common blasting media, at least that I've seen, it's more common for finishing harder metals. It's extremely hard.


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## degarb (Dec 12, 2016)

Pardon my ignorance. . You build drivers at home or work? . How do you sintering the SiC? Do you press, or heat? What tools, and how doesn't it damage the electronics? 

Back to my storage question. . I found a Christmas tin, buried the aluminum powder in it. . I dread mixing AL into the epoxy outside in 0 to 20 degree enough. I dread worse a 150 foot walk to retrieve it from my detached garage. . So, if basement caught fire, eventually eating through the tin and soda packing, are we talking high rise explosive, or just another problem upon many as your house burns up, gas pipes exploding?


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## scianiac (Dec 12, 2016)

I have built drivers in the past and still do sometimes but it's often easier to just buy them. I do it for hobby and work (I sell modded flashlights). I don't sinter the SiC, that would be very hard. I just use it as a filler for various other materials, epoxy, silicone, Butyl rubber composites, etc. Whatever best suits the application. Those are used to pot drivers and generally thermally attach things.

Really there is probably little risk it will even combust. Unless you bought pyrotechnics grade alumnium it's probably safe. The pyro grade stuff is very fine, often in flake form, and has additives used to prevent oxide layers forming. Sitting still in a tin it may not burn even if lit. Handling it is when you have a risk, when it becomes airborn there is potentially enough exposed surface area to cause an explosion in just the right conditions. This is why if I were you I would take very good precautions against static discharge and other ignition sources when handling it. The zap from static discharge could be enough to ignite it in the air, again in the right conditions. And try not to get it airborn in the first place. Do you know the size of the powder you bought? Generally smaller than 40 mesh (420 micron) are where the hazard starts.


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## degarb (Dec 12, 2016)

scianiac said:


> I have built drivers in the past and still do sometimes but it's often easier to just buy them. I do it for hobby and work (I sell modded flashlights). I don't sinter the SiC, that would be very hard. I just use it as a filler for various other materials, epoxy, silicone, Butyl rubber composites, etc. Whatever best suits the application. Those are used to pot drivers and generally thermally attach things.
> 
> Really there is probably little risk it will even combust. Unless you bought pyrotechnics grade alumnium it's probably safe. The pyro grade stuff is very fine, often in flake form, and has additives used to prevent oxide layers forming. Sitting still in a tin it may not burn even if lit. Handling it is when you have a risk, when it becomes airborn there is potentially enough exposed surface area to cause an explosion in just the right conditions. This is why if I were you I would take very good precautions against static discharge and other ignition sources when handling it. The zap from static discharge could be enough to ignite it in the air, again in the right conditions. And try not to get it airborn in the first place. Do you know the size of the powder you bought? Generally smaller than 40 mesh (420 micron) are where the hazard starts.



500 mesh µ30 micron , he-he.

Still, not opened it. Outside, is a must. Never seen static electricity outside. Do I need to pound a pole in the ground and wear a metal wrist strap,attached to a metal wire? Could share with the Dog.

I need to lookup the thermal charactistics, etc, to see why you add SiC to silicone and epoxy. Watched big Clive add cornflower to silicone to make some good forms for epoxy led Christmas light diffuser.

I am thinking best setup would be zip bag of aluminum in tin of baking soda, inside metal paint bucket. Unsure if empty space is more heat insulation than sand around tin. Of course, sand on bottom to insulate there. Also,probably skip paint bucket and go for a Christmas popcorn tin. Great excuse to eat a tinful. And I must do it quickly, else the house may burn.


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## degarb (Dec 12, 2016)

Maybe adding SiC to the epoxy, for density reasons? Is it really light weight? Good thermal but not near aluminum or copper.

I see on glass guy on YouTube using wine glasses on SiC to etch glass. Stumbled on last year when researching cirium oxide to buff out scratches in glass.


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## degarb (Dec 13, 2016)

I have been pondering potting electronic board with delicate protruding components, where I may wish not to shroud inside, and wish to keep as lightweight as possible. All my lights are worn and carried on the person.

Probably spray polyurethane foam ground to size,but impractical as a can is single use. Considered artificial plant styrofoam that is easily moulded and glued on, where regular foam might be too heavy but less crushable. Also, considered light weight spackling, which may need a paint or caulk additive for strength. Haven't yet tested any ideas.


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## degarb (Dec 13, 2016)

scianiac, are your drivers AMC based? You cap them on positive and vdd? Or something different?


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## scianiac (Dec 13, 2016)

OK yeah that is some seriously fine stuff, would be careful with that. A grounding strap like you described would be a good idea. The metal storage strategy you described sounds good. I use the silicon carbide for the same reason you do, but also because it's non electrically conductive so it can be safely used as potting. While I don't know the exact thermal conductivity of this silicon carbide it's likely that it's 6H (alpha) type so has a thermal conductivity higher than copper. If it's some other form though it's still quite high in the range of aluminum. It doesn't have have any more of a thickening effect on silicone than any similar powder I think cornflower thickens it into a putty quicker, love big clive btw. 

SiC is lighter than copper. As a thermal filler it's probably between aluminum and copper in overall effectiveness, copper's specific heat is better. But I don't feel safe covering electronics in copper or aluminium dust.

If you want to pot drivers for vibration and impact reasons as you described. I also like keeping EDC things super light but it's hard in a light, more mass in the head means more thermal mass which means longer runtime in turbo. Silicone, epoxy, duct seal mixed with SiC probably won't add that much weight unless the pill cavity is huge. If heat is not and issue and you just want a lighter potting you could just cover the driver in a thin layer of epoxy instead of filling the whole cavity. Weight and thermal conductivity just don't go together. Anything that will be super light will also be not very conductive. You could use glass micro balloons as a filler and it will be light but not very conductive. 

You might want to try some potting with a duct seal based mixture. You can get it at the hardware store in a brick for a couple bucks. You just mix that with your filler of choice like you are mixing clay, just mix in as much as possible (start with a small batch as you'll get tired out otherwise). It's easier to use than epoxy and can be easily removed if you need to change, adjust or fix the driver. You can just pack it in the driver cavity and/or on the board and squish it in there.

I use all types of drivers, I've mainly built the various BLF driver designs. haven't had a need to design my own yet but a few current projects I think I will. But I use mostly FET+7135 and buck drivers in both personal and production lights. And as much as I enjoy building them it's just easier to buy them, building a few is fun, building 20 is much less fun. The potting is very important on the buck drivers both to dissipate heat and prevent the inductor from breaking if in an impact.


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## PhotonWrangler (Dec 13, 2016)

It sounds like you're taking the right precautions, Degarb. Don't forget to wear a dust mask. Aluminum in the lungs is not a good thing.


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## degarb (Dec 14, 2016)

scianiac said:


> OK yeah that is some seriously fine stuff, would be careful with that. A grounding strap like you described would be a good idea. The metal storage strategy you described sounds good. I use the silicon carbide for the same reason you do, but also because it's non electrically conductive so it can be safely used as potting. While I don't know the exact thermal conductivity of this silicon carbide it's likely that it's 6H (alpha) type so has a thermal conductivity higher than copper. If it's some other form though it's still quite high in the range of aluminum. It doesn't have have any more of a thickening effect on silicone than any similar powder I think cornflower thickens it into a putty quicker, love big clive btw.
> 
> SiC is lighter than copper. As a thermal filler it's probably between aluminum and copper in overall effectiveness, copper's specific heat is better. But I don't feel safe covering electronics in copper or aluminium dust.
> 
> ...



Excellent post.

Haven't yet measured electrical conductivity in even my Cu epoxy mixture. That isn't to say there isn't any, as my tests were a casual ohm meter check as a side curiosity, and probably didn't push probes very hard.

Only one reading of this thread,on the run. It seemed to me you were saying SiC thermal conductivity is between Al and Cu.?

Do own boards or cccv boards (though I want a cccv board that can jump my phone), need thermal potting? Naturally, in use, I will know, if something gets hot, I guess. Not noticed any heat at all on the pwm board. Not received my cccv boards yet from fast tech, though I have a uniden 18650 power pack I can employ, were I 100 percent confident it doesn't register current once cell reaches 4.2 volts. I got 3 cheap 2bay China chargers in spring, which I can measure current at 4.2 v cell. My intellicharger seems to mostly shut off at 4.2 maybe CV pulse. Using the cheap chargers only when no other option, even though all my cells are protected, except a few free ones I have in holder for emergency. Charge in cookie tins. 

Now, on digikey the cccv chip is pennies, just add your own caps etc. Boards are like 2$, any good charger should be 8bay and have volt readout. If not on each bay, one volt meter on side you can use one hand to press cell into v , get voltage onto and off charger (2-3seconds max per cell)..... Making your own charger with magnets might not be too hard, if one knew a good choice for acdc transformers.


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## scianiac (Dec 14, 2016)

Metals mixed into epoxy often won't be conductive until you add a ton of metal but even still I'm not going to risk it across the close pins of a driver. SiC's overall thermal performance I would say is about in between. It's thermal conductivity is higher than copper but it's thermal mass (specific heat) is more like aluminum and thermal mass is very important too, at least when you make really powerful flashlights.

Most boards like that probably don't need any potting unless you want to water proof them. Then again cheap Chinese electronics are known to sometimes use undersized components that get a little toasty.


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## degarb (Dec 15, 2016)

scianiac said:


> Metals mixed into epoxy often won't be conductive until you add a ton of metal but even still I'm not going to risk it across the close pins of a driver. SiC's overall thermal performance I would say is about in between. It's thermal conductivity is higher than copper but it's thermal mass (specific heat) is more like aluminum and thermal mass is very important too, at least when you make really powerful flashlights.
> 
> Most boards like that probably don't need any potting unless you want to water proof them. Then again cheap Chinese electronics are known to sometimes use undersized components that get a little toasty.



I wish to know a good source for micro glass beads and SiC.

In addition to the electronic stuff, for my headlamp builds, I wish to build the lightest, most practical firewall under the protected 18650 holder to protect the head. Also, for my wrist lights. Need padding, so silicone probably best rubber choice. Layering in strips of aluminum foil, which has reflective and a 660c melting point(silicone ignites at 1000c, I am told), while add nothing to weight-- is one idea in my head. Adding micro glass beads to the silicone, another idea. Adding borax to the silicone, as a cheap alternative to glass beads--which may be redundant, but I must think about this more. Adding fiberglass mesh, for whatever it might be worth. Maybe someone has better ideas.

Bondo polyester seems cheaper for resin than epoxy for potting. 

I never have worked with fiberglass kits; but to me, look like a thin polyester resin with fiberglass reinforcement strips. The significance is this fiberglass could be used as filler or there could be sheet properties of fiberglass like shape, fireproof or weight.
www.instructables.com/id/Homemade-Flame-retardant/?amp_page=true?

https://www.wou.edu/las/physci/ch462/BouncingPutty.htm

http://makezine.com/projects/make-40/fond-o-bondo/

https://www.google.com/search?q=micro+glass+beads&oq=micro+glass


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## degarb (Dec 15, 2016)

Actually, I am getting conflicting results googling silicone melting and ignition points. Some say it never melts and only ignites at 1000C, some say 300C melting with ignition point of 1400C. 

GE has some junk called silicone 2. When I use that junk, it never dries for me. Probably how hard I squeeze it from tube....my point is that probably traditional silicone caulk all works the same. While silicone 2 may be doped and have a melting point. Hopefully, the case.


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## chillinn (Dec 15, 2016)

degarb said:


> Never seen static electricity outside.



Sure you have! Lightning is electrostatic discharge, and thunder is the result. And I'm not talking about the heavy stones at the ends of your wrists.


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## degarb (Dec 15, 2016)

Another essential side point:

Pure 100℅ Silicone rubber caulk is what I use to water proof shoes, reinforce work boot seams the day I buy the boots; I put on back of leather gloves to double the second warning before the grinder grinds into your hand. I have seen serious shrinkage of tripolymer caulk on a 2006 built house this year. Read it shrinks less than polyurethane over the decades. Who knows?

So, the problem with pure silicone is storage. Once opened, I think the tube has a self life of days, no matter how to seal it. Buy 12oz for $3.99 or 4oz for $3.99. 

According to this website below, this guy's company freezes their silicone to extend the shelf life. The base smells like vinegar, so you would think freezing would kill the tube. But I found theories only take you so far, as the real world surprises with unimagined variables.
http://www.sawmillcreek.org/showthread.php?72231-Is-unused-silicone-caulk-still-good-after-freezing


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## degarb (Dec 15, 2016)

chillinn said:


> Sure you have! Lightning is electrostatic discharge, and thunder is the result. And I'm not talking about the heavy stones at the ends of your wrists.



Thanks for pointing this out. Great point.

Still, on human level, what conditions (dry air, but what humidity level and footing?) Can it occur? It is odd it occurs in a dry house, while lightning in wet outside. The forces must be of vastly different scale, between the two.

You know, I do recall touching my car door and seeing a spark once. I don't recall what I was wearing or the weather. Barely recall the incident. Maybe usually too humid where I live.

So, touching a car or ground spike, before opening container. If spark, might wait a day, or go to hardware store for a grounding wire.


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## scianiac (Dec 15, 2016)

I find it's easiest to get silicon carbide on ebay, with shipping it seems cheapest. If you search "microballoons" you can find all sorts of the glass bead type filler I described, they are pretty much what it says, they are very tiny hollow glass spheres. Not sure I would want them in anything directly exposed to skin but they do make things lighter since they are mostly air.

Most silicones you get at the hardware store and such are tin condensation cure, keeping them cool and dry and of course sealed is the best way to keep them good after opening. Having tried all of these, don't bother just buy smaller tubes or 2 part platinum cure. If you have a very thick section of tin cure silicone they often will take a very long time to cure, this can be sped up by putting them in a warm and very moist environment, I've used an old toaster oven with a pan of water in it. I can't remember the exact ideal temperature. For potting or molding a two part silicone is probably better, like those sold by smooth-on for example. 

Silicones generally don't "burn", they decompose into silica, leaving behind a white powdery substance. The exact temperature depends somewhat on the type but around 500F seems about the average. If you want to make a "firewall" to protect your head from a battery fire you could just go with the nomex/fiberglass bags sold for containing lipo fires. Or go on get a silicone baking mat, they are quite cheap on amazon. Rated for 500F+ and fiberglass reinforced. You just need to buy enough time to take the thing off your head not to fully contain it.


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## chillinn (Dec 15, 2016)

degarb said:


> I do recall touching my car door and seeing a spark once.



Aparently, this is a thing, and people have been seriously injured from it. My understanding is it occurs commonly in open concrete parking garages, especially in Asia, where there is some market for antistatic devices for cars.


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## scianiac (Dec 16, 2016)

It also is increased by low rolling resistance tires, which are coming standard on more new cars.


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## degarb (Dec 17, 2016)

chillinn said:


> Aparently, this is a thing, and people have been seriously injured from it. My understanding is it occurs commonly in open concrete parking garages, especially in Asia, where there is some market for antistatic devices for cars.



So, I have options of mixing the powder aluminum on my old concrete side porch, my Wood back deck, grass, snow, or stone drive way. Bare foot, or rubber shoes.

I take it concrete porch is worse choice. Old, so probably pitted.

Btw, scianiac, loved your reply, learned something important. Grateful.


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## degarb (Dec 17, 2016)

Sci, the problem with buying an silicone pad may be the attachment. . Nothing sticks to silicone. . And it doesn't stick that we'll. . Also learning to build your own solves other issues in unrelated areas. . More to learn. 

Anyway, I have a little phobia of fires. Not so much being burned alive. . But they aren't generally welcome by property owners, who apparently dislike insurance adjusters, for some odd reason. Only had one drop cloth-where catch fire and one electric outlet burst into flames. Unrelated incidents. So, this is why I have a five of blasting soda, carry fire extinguishers & gallons of drinking water(and ready full bladder) everywhere, and interested in borax soak of my drop cloths post final rinse of a washing machine. . But do i need buffer with boric acid? . Tried a few years ago to use a 2:1 ba/borax for dry rot prevention - didn't work, as area was too close to the soil. . I assume buffering reasons is why you add borax to boric acid . . The below link has adding them both to wood for fire retardation. Looks like %5 is target. . Maybe a spray on (if solution can go through the nozzle) is better and more practical, than a wash? . 

Interesting reading, at any rate. . Also stumbled on something weird and intriguing called papercrete - unrelated to lighting, for now. 

https://www.hindawi.com/journals/ijcc/2011/146763/

http://www.greenhomebuilding.com/QandA/papercrete/ratio.htm


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## degarb (Dec 18, 2016)

Been working and shopping all weekend. Got to a Walmart super store tonight. . No time for serious reading up. 

SHAZAM! Just tested and just found out that borax does thicken silicone 1 caulk. Much as the YouTube videos described corn flower thickening . A 1.5 inch thick test chunk had a working time of 20 minutes, while the pure silicone caulk is still as wet as it was 45 minutes ago. . The untreated silicone looks like it will cure days from now. 
According to Google, no one mentions mixing the two. 

Actually, I did sever random mixtures of borax to boric acid powder(though on wood, it was some 2:1 ratio, I didn't recall, nor had easy internet access to relearn) . . Tried to mix 1:1 powder mixture to clear silicone. . I wanted clear to visually see the powder saturation into the caulk. . Also the mix doesn't seem to have affect on the good adhesion to the bottom of the pie pan used as a mixing cup.

I probably will need 2 weeks to flame test the pure silicone v. The borax silicone. To see if any difference. . If not, at any rate have a non organic thickener. . I will do a corn starch sample too, for the burn test. . Though, I would think adding corn starch would hurt flame retardation. 

Reason for my haste is one of my China direct t6 35mm 18650x2s headlamps(probably called magic shine with some overstated lumens, I only altered the driver) that I put to use daily on job, had a thin silicone firewall piece that used piercings and wire to hold in place between back of head and the two 18650s. . Naturally, it broke off, and being silicone, nothing could a fix it back onto the battery compartment. . So I epoxied on two fabric flaps, epoxied to a pie aluminum rectangle, then lapped on a thick layer of borax silicone. Set a thin under sized foam sheet, covered in thin layer of silicone. . Time will tell if this holds up or is comfortable. . ( layers of fiberglass tape makes more sense than the aluminum, but all I have now tonight)


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## degarb (Dec 18, 2016)

http://www.americanborate.com/all-about-borates/borate-applications/borates-in-flame-retardants/

Though boric acid in methyl alcohol burns green. . My concern is that unwrapping a lipo cell phone battery, to me, smelled like mek.


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## degarb (Dec 19, 2016)

Magnesium hydroxide, key antacid ingredient, used additive to resins as a flame retardant, probably already in your house. 

The most common inorganic flame retardants are the hydroxides or aluminium and magnesium. Aluminium trihydroxide (ATH) is by far the most widely used flame retardant on a tonnage basis. It is inexpensive, but usually requires higher loadings in polymers of up to more than 60% because the flame retardant mechanism is based on the release of water which cools and dilutes the flame zone. Magnesium hydroxide (MDH) is used in polymers which have higher processing temperatures, because it is stable up to temperatures of around 300 °C versus ATH which decomposes around 200 °C.

http://pinfa.org/index.php/en/flame-retardants/what-are-pin-frs


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## degarb (Dec 19, 2016)

I should report my initial flame results. I did an early test to see what I could learn. . Early in the morning, I picked off two small pieces of the silicone caulking, squeezed out onto the pie pan the night before. One small piece was roughly 50% (far from exact) borax/ba : the other was just the pure GE silicone 1 caulk, from 9pm night before. 

I held the small dried borax silicone in left hand (outside, over snow and concrete) and took a butane lighter to it. . Unfortunately, it ignited :but, once the flame was removed, it self extinguiched in under 2 seconds. . Holding second, untreated, pure silicone piece, it too ignited. . This time, larger flame that continued to burn for a full 10 seconds, until I blew it out to protect my fingers. 

I must conclude that 1 day old silicone has flammable oils present. . I am guessing it may take months to dry out enough that it won't burn-probably, when all smell gone. . The borax additive does appear to be combating the flame as expected, as well quick cure thick molding. . Though not enough flame control to prevent ignition in the first. 


PS. Walmart didn't have any fiberglass reinforced silicone mats or mittens. . They did have a weird oven liner that looked like regular plastic, and had bad reviews saying it smells like burning plastic.


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## degarb (Dec 20, 2016)

degarb said:


> I should report my initial flame results. ....
> 
> I must conclude that 1 day old silicone has flammable oils present. . I am guessing it may take months to dry out enough that it won't burn-probably, when all smell gone. . The borax additive does appear to be combating the flame as expected, as well quick cure thick molding. . Though not enough flame control to prevent ignition in the first.




Just tested the silicone firewall of the chinese headlamp. No ignition with open flame.

I suppose buying a good fiberglass oven mat, cutting to size, is the safe way to go. The problem is that nothing I know will glue to silicone. I would need to get fiberglass tape and make a "pouch" to slip the oven mat into...I have zero experience with fiberglass tape other than pictures and video. (The msds, online, for silicone caulk alludes to MEK and mineral spirits. Silicone 2, just doesn't become acidic when drying, so is better for plastics and some metals-according to GE. I guess bad batches of Silicone2 (old), are common, where they fail to dry. This was my only experience with silicone 2. Also, Silicone 2 is paintable, which make me doubt if it is pure silicone.

Btw, the borax clear silicone, dry, looks exactly like snow. Very seasonal, for anyone looking for another way to make snow in a model or a decoration.


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## degarb (Dec 20, 2016)

http://www.ebay.com/itm/Fiberglass-...ash=item211b8c6287:g:KwEAAOSwB09YPsYA&vxp=mtr

For the pouch part, to secure the silicone. Or should I guy something locally?

For the silicone oven mat?: 
http://www.ebay.com/itm/Non-stick-O...847968?hash=item4868bcc8e0:g:Qt0AAOSwgyxWT83b 
or
http://www.ebay.com/itm/3-Pack-LARG...736165?hash=item1c60e57aa5:g:0jIAAOSwKtlWssMW


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## degarb (Dec 20, 2016)

http://www.ptfe-supplier.com/non-stick-oven-liner-baking-liner/9406769.html

ptfe supplier, hmmm...


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## degarb (Dec 20, 2016)

Best explanation yet: 
http://texasezlog.com/flame-retardants.html

Disodium octaborate tetrahydrate... 

Dot, effective against mold, dry rot, pests, fire. . Basically, hot water borax and boric acid, perhaps? . . Never understood pH well, even when studying covalent shells. Definitely, don't remember much beyond a pH strip and, "acid plus a base equals salt plus water!" (and then, only because it was the school cheer.) . . So, I am guessing the synergistic coupling of the two is why formulations recommend both, and not pH reasons.


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## scianiac (Dec 20, 2016)

With proper surface prep and a decent surface area silicone will adhere to silicone. I think some of those oven liners may be teflon or some other material, the ones I've used for a number of things like the second ones you listed sold as baking mats you actually bake on, which they work great for actually. Either way they will probably be good. If anything I wouldn't be worried as much about how good the backing material is, even one layer of baking mat would probably be enough but 2 or 3 would take a tremendous amount of heat to burn through. You may want to focus more on surrounding the cells if. If you watch how these cells fail, they normally vent, ideally quality cells vent in a controlled manner at the button end, but they can form a hot jet which could in theory shoot out the side around the backing material. So maybe one layer on all sides would be better than several only on the back or make sure you have something around the button side. In fact I don't know that fire retardants would even be very effective in a lithium battery fire, I know that water is pretty much useless and most fire retardants are designed to prevent something from burning by being mixed into it, in this case the silicone is already not flammable so the chemical action of the fire retardants may be wasted being so far from the fuel. I already presume you are using high quality cells cared for very well, which is certainly the best way to prevent a fire.


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## degarb (Dec 20, 2016)

There are many suggestions on the below link. . Which strategy would you recommend for gluing silicone? 

http://www.instructables.com/answers/What-glue-can-I-use-to-stick-silicone-to-plastic/


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## degarb (Dec 20, 2016)

On the other issue, my current strategy is only Panasonic 3400 protected, measuring voltage on/off charger, using tested (to ensure no flow at 4.2v into cell) intellicharger. Cc controller with low dropout. 

I have not fireproofed the entire sled, only part touching skull. I was pondering metal tape lining the 18650 holder to barrier the plastic holder. . It would be nice to fireproof all around cells to prevent property damage, but never thought it practical, in the past. 

Now, my fire test is with GE 1 caulk, which shows early flammable vocs left on surface. . Probably, other brands would flash off sooner. I could heat gun to see if that helps the vinegar smell go away. . Second day, and still strong smell. I need to go to smooth on and see what they have to offer. 

The borax was a test, for curiosity sake. . I never expected the silicone caulk to be flammable after 2 hours, nor 2 days. . The untreated silicone is still wet one inch in, while the borax/boric acid doped silicone set in roughly 20 minute. . Same amount roughly. . I must remember to do a corn starch sample, to see if it adds a fuel to the rubber. . Also pure borax v. Pure boric acid. 

Then there is the issue of colored silicone caulk. . I believe colors are clear, white, black, and silver. . Not sure which pigment would do what... Of course, the caulk route is dead if the vocs don't go away in a reasonable amount of time and it remains ignitable too long. Then, the mat is the only option. Or maybe 2 part silicone. 

Of course, I have other fire prevention interests. . Drop cloths near my metal halide lights, the area rug 3 foot from the space heater, kid room carpet. Oh yeah, just occurred to me, I should upgrade my light bag to silicone (interior, at least), which I use to carry several head an wristlights back and forth each day to work. . I actually should firewall lights from each other too-somehow, without adding too much bulk. Maybe, making headlamp pouches from the fiber glass cloth and covering in silicone. . So silicone cost may be an issue, as I see too many uses for the stuff.


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## scianiac (Dec 21, 2016)

I mean if you can avoid it don't try to glue silicone but it kinda works if you of course clean the surfaces with a solvent then just apply more silicone. The problem really is all those tin cure silicone caulks just take forever to cure an any cross section thicker than like 1/8in. A thin layer on fiberglass probably could cure much faster. It's a shame two part silicones are a bit on the expensive side, you can get those they cure in like 5 min. Maybe you could find a place that has them a bit cheaper. 

Or try the speed curing the caulk stuff. Like I said I don't recall the exact temperature but I want to say something like 150F in a very humid environment. I had a 1in cylinder shape of solid silicone and it was still totally soft on the inside after like a week, few hours in the toaster oven with a tray of water and it was solid all the way through. 

For bags though, you can get lipo bags in many different sizes. Not sure if they are fiberglass or nomex but they are made to be fire resistant enough. I've only seen them fail when put under serious conditions, like trying to contain a purposely shorted massive RC lipo. And even then the stitching failed due to the force, no heat damage.


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## degarb (Dec 21, 2016)

First few hits, for lipo bags, are pretty pricey. . Nomex is a material I probably heard of but didn't register. . The lipo bags are "space age materials", so I can assume made of moon rocks or asteroids, rather than Nomex, silicone, or fiberglass. 

These moon rocks seem to add to much to the cost of these lipo bags. . Looking to me like I need to get fire resistant material and staple/glue/sew my own bags. . I want about 8 to 18 thin small ones to contain each light and one small book bag to carry and store. . Actually 3 book bags. One for daily needs, one for extra heavy need jobs, (and backups), one to replace bag when it wears out in 8 months of service (can be used as overflow as needed) .

I will need to price Nomex and find out cheapest /thinnest material I can get away with. 3 sheets of Fiberglass cloth, sandwiching in 2 layers of silicone maybe. Who knows, unless testing. . Maybe. Minimally until then, I should use non aluminum foil, maybe sandwich silicone caulk between two sheets. . First flame test, naturally.


.... Geezer, steel foil is apparently too rarely needed, and priced as a rare commodity. . So, probably silicone caulk infusion of fiberglass cloth, stapled seams. I wonder if adding aluminum foil to the setup might buy some specific heat time or heat reflection time. . I know it melts at like 600 C a bit above silicone breakdown, and EVEN a candle burns at 1000C. Buying time and combining strategies.. 

Maybe the 18650s vent side should have flame proof (resisting) foreskin. . Just a thought.


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## degarb (Dec 21, 2016)

Holy exploding Samsung! This you tube guy melts a penny on top of treated cellulose insulation. The fiberglass insulation melts. 

https://youtu.be/8NC79e0oztM


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## degarb (Dec 21, 2016)

72 hours out, the ge silicone caulk still readily ignites. . The borate treated rubber seems harder to ignite but it does, eventually, but self extinguishes. . Made a cornstarch, a pure boric acid, a pure borax, filled silicone samples tonight. All three thickened and sped cure of the thick samples. I did add food coloring and some paint. . Colorant seemed to interfere and cause separation. Maybe or maybe my techniques. Got a white with pink glaze, rubber heart, green k and orange m, out of it. . No inspiration apparently. The burn tests will be interesting. . I predict corn starch rubber silicone caulk to burn well. . Borax ignition resistant. The boric acid slightly better than nothing added to the silicone caulk. Based on reading. . Interesting the pure borax sample had least odor, wile the boric acid had worst odor on dry sample... Micro glas balloon fill would be interesting test. 

. So for now, look like stuffing a liion filled light bag with cellulose insulation is the quickest solution. (I never would have thought it so. ) It would be easy to wrap each light, individually, in aluminum foil. . I just feel that is asking for a short circuit unless I could electrically insulate the foil without adding fire fuel. 

Now, I am assuming most brands of silicone 1 caulk tubes would have simular ignition in early days of post cure. . Else I would run out and buy other brand. I haven't tried oven or heat gun to dry out the cured caulk of its oils, mostly because this would not be practical in most applications.


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## degarb (Dec 22, 2016)

Also, I should know more about nomex. . Variants, ingredients, competitors. 

Amazon has nomex fabric with no mention of flame retardant properties. 
Nomex

https://www.amazon.com/gp/product/B0176YO6W0/?tag=cpf0b6-20


http://www.dupont.com/products-and-services/personal-protective-equipment/nomex.html

https://www.amazon.com/gp/product/B00TOT7K1K/?tag=cpf0b6-20

https://www.amazon.com/gp/product/B016YEOYJS/?tag=cpf0b6-20


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## degarb (Dec 22, 2016)

Butane lighter test this morning. Neither the green food color/boric acid silicone caulk, nor the borax/orange silicone, would ignite. Areas with ample borax/boric acid in the sunday mix wouldn't ignite. The pure silicone from Sunday and the corn starch mix sample, both ignite and sustain/growing in intensity.

I think key was getting enough borates into the mix. I was surprised that boric acid worked as well as the borax in this test. 



What I am seeing too is an unreasonable price tag on most fireretardant sprays for canvass. I am sure it is dirt cheap to make and anyone could use many large buckets of the stuff annually. But, the market is the market, and liability factor is likely their main cost. (They will always get sued, even if the product works great. There is always that 1 in 100 person that ruins it for the rest.) In 15 minutes of searching, I am only getting some ace hardware fireproofing acrylic caulk. Which means limited flexibility, perhaps. And, one british dealer of fireproof silicone caulk. And one home depot online only $190 minimum order for 12 tubes of fireproof silicone caulk. To be fireproof, they would need a hotter solvent that would flash off quicker from inside the rubber-a different cure method than the GE stuff. Fire protection after 6 months of cure is fine for a house that takes 6 to 12 months from dig to paint to carpet; but not good for a homemade headlamp or liion carry bag.

http://www.homedepot.com/p/DAP-Fire...Silicone-Sealant-12-Pack-7079818806/205030322
http://www.acehardware.com/product/index.jsp?productId=2151134&cp=2568443.2568447.2624903.2624911

Now, while mixing enough borates into the caulk ensures flame resistance, enough borates lowers the adhesion. Needed adhesion to the inside of a bookbag, onto aluminum foil, onto fabric. This is problematic, at least in theory, for using silicone caulks. Even before using the store bought fire proof silicone caulk, I would flame test it myself.

Probably, my next tests should be in fireproofing material, best mix and application. Also, (silicone and other) water proofing over or within the solution.


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## degarb (Dec 23, 2016)

New flame tests results:

1. Bought silicone closeout phone case and 6 silicone coasters (with same stretch as the oven trivet at Walmart). The phone case wouldn't ignite with flame exposure. The silicone coasters must have been cut with something; so, the silicone coasters readily ignited by a mere butane lighter. .. I would test their overpriced oven trivet for ignition, before using.

2. High heat black 1100 C spray paint, ignites when dry.

3. Waterbased polyurethane caulk, ignites when dry.

4. Silicone 2, low odor caulk, ignites when dry.

5. Neither silicone2 nor the poly make a moldable putty with addition of the borates. But they do make a borate paste that resists ignition. Though, I suspect the higher odor silicone 1 is the way to go.

6. The edges of fiberglass cloth melt readily. But in the center, can with stand a flame for many seconds, before I got bored/satisfied and tried another test. Coated with borate silicone caulk (no ignition/good insulation for a butane flame), should work okay as a firewall-this setup, will be blow torch tested later.

7. A coating of borate silicone on both sides of a highly flammable old rag, did make it flame proof from the butane lighter. Though it became rubbery. Probably not as much for a blow torch.

8. I need to review youtube 18650 to see the duration that the firewalls will need to withstand.

9. I was impressed with the amount of fiberglass cloth for $7 that ace hardware gave me.


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## degarb (Dec 24, 2016)

Also, just noticed the blue butane flame turns green while trying to ignite the borax silicone. . 

The silicone coaster ignites easily around edge would burn about 3/8 of edge before the char extinguished the flame. . Trying to ignite flat side in the middle didn't ignite the lighter,probably due to char layer. But only took 20 seconds to get too hot to touch. 

Full 70 second burn of the fiberglass cloth with lighter, insignificant char. . Impressive... The borax infused silicone slather on fiberglass fiber, had best insulation per thickness, via finger test. 

The standard 2s18650 holder is crazy flammable in flame test. I am thinking of foil tape until I figure better method. 

The plastic


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## degarb (Dec 25, 2016)

When boron compounds are heated, electrons absorb a certain amount of heat energy that causes them to jump to higher energy levels. After some time, the electrons lose this energy and fall back down to their original levels, emitting this energy in the form of light. Because the energy absorbed by electrons is different per element, each element will give a different colour.


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## degarb (Dec 25, 2016)

http://wildfiretoday.com/tag/tennessee/


Wow. I just learned my mother's time share burned down . Codes and unfounded asbestos phobia really failed 14 lives and destroyed 2000+ homes and businesses .

I don't get this attitude that the modern person should rely on fire departments. . Crowd source dirt cheap fire retardants. . Undercut the entrepreneur with government distribution, raising supply in the supply demand equation. 

http://oregonstate.edu/ehs/asb-when

For all the lawyers. . Got living relatives that swam in the stuff in the 60s. Though encapsulation within a resin is important. . Do need to invent a "do not disturb" flag for future residents, long into future. Maybe, something on deed, that the county auditor website, rfid tag, titanium stamp, or one of those mattress tags people are terrified to remove. The danger lay in contractor disturbance without proper vacuums. Not rocket science. . You don't pump gas smoking. Don't operate a phone when walking or driving-either can be fatal to you or others... The bottom line is a fire is far, far worse than encapsulated fibers. . Asbestos is amazing stuff for insulation and fire. . Siding wise, way better than vinyl or aluminum. Holds paint forever , easy to paint 4 sides of a house in a few hours with roller and extension pole. Another mineral, among others, which should be cheap enough to fireproof every home worldwide. . So, price does matter, if maximum number of lives, is the goal. . You can take your "only for the elites" solutions.


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## degarb (Dec 25, 2016)

https://youtu.be/ZTzEHsJVZhA

This is a video where they simply and quickly short an 18650 with pliers. 

Several things are immediately apparent to me. 1. How easy it was done, means more work should be done to paint the 18650 metal before wrapping for bullet proof insulation. . Light manufacturers need to redesign their lights for thicker and longer protected cells . 2. There is plenty of warning that a voc or other vapor sensor could beep a warning. Maybe the vent rush itself could trigger. If a protection circuit is size of dime, so could a warning circuit be designed. 3. The flame out was short lived. So firewall is doable and may not be so hard to do. At least in this single cell video.


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## degarb (Dec 25, 2016)

3m has video here of their FP products:
https://youtu.be/0x0v1mRk5xw

The endothermic mat looks exciting, until you see the price tag of 800 bucks for 20 foot. Your money or your life, scenario, but they are not holding a knife, just a polyopoly.


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## degarb (Dec 25, 2016)

https://books.google.com/books?id=U...zAD#v=onepage&q=resin locked asbestos&f=false

I also didn't know that all asbestos diseases, with very few exceptions were occupational. Traced triggered asbestos cancer, without exception, happened in people that also smoked frequently and regularly. . Nevertheless, fibers in the lungs that never leave from disturbed asbestos, just creeps any thinking, air-breather out. . Not as much as burning to death, but still bad. .


I can attest that most workers hate respirators. . I know, personally, that a good nonforced air respirator makes a 4 hour day fatigue you (a fit 20 something experience) like a 12 hour day. Smokers find them even harder.


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## degarb (Dec 25, 2016)

http://randomnerdtutorials.com/21-arduino-modules-you-can-buy-for-less-than-2/
This link is for a ton of useful arduino detection modules that I was unable aware. . Heretofore, ads for arduino really did nothing I really saw as most efficient method. Maybe it is worth the time investment to look into. 
I really want a micro sized, cheap fire/ smoke detector. About 20. One for my light bag, two for each room in my home. And one for every step ladder and light stand I own... Doubt if tech is here to make them this small, low drain, or Cheap. 

People who have hundreds of apartments need a bicarbonate releasing detectors that can prevent the sprinklers going off, which cost most complexes thousands annually.


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## PhotonWrangler (Dec 25, 2016)

The gas sensor modules include a heater, so they don't fit well into the category of low drain, however they are fairly small and a complete sensor/arduino/battery could fit into something the size of a cigarette pack.

What I think you need for your home is a combination of ionizing and photoelectric smoke/fire detectors. One senses smoldering sooner and the other senses fire earlier.


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## degarb (Dec 25, 2016)

I haven't considered crushed lava rock as a lightweight, insulating filler. 


Checked the batteries in my home detectors last week . . Bought 3 cheap ones last year. The one by stove died, likely from repeated false alarms. . Then yesterday I did some flame tests in a pie pan in the basement of the original silicone 1 test sample. . Right below the detector. . Didn't trigger. So, pw, your right. 

Pw, I see your posts referencing the arguing tech. . You need to bring me up to speed on the most useful applications.


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## PhotonWrangler (Dec 26, 2016)

degarb said:


> Pw, I see your posts referencing the arduino tech. . You need to bring me up to speed on the most useful applications.



Degarb, I'm thinking that an Arduino temp sensor will be a good fit for your bag. You would need an arduino, a Dallas Semi temp sensor chip, a piezo buzzer, a battery holder and some wire.

Here's an example from a guy who built a high temp alarm for his freezer. Replace the blue led with a piezo buzzer and change the else-if line in the example code from *farenheittemp <= AlarmTemp* to *farenheittemp >= AlarmTemp* and you should be good to go. The buzzer will sound when the temperature exceeds whatever alarm temp you set it for.


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## degarb (Dec 27, 2016)

More fire tests under the non responsive ionization fire detector, results:

1. Adding borax or boric acid to 6 minute epoxy, makes it flame proof. And, makes it somewhat intumescent; or at least 1 mm swells to 6 mm when exposed to flame. Even straight boric acid works without making it coarse; however, it does make it brittle and less adhesive (to aluminum pan, at least). 
2. Adding borax to Amazing goop makes it fireproof, but makes it slightly crumbly. (Only silicone 1 caulk and the epoxy, are not made crumbly.)
3. The borate epoxy was effective as a thin paint over the highly flammable battery holder, to make the holder flame resistant for at least 20 second flame test. After 20 seconds, I would need further testing to see if pin holes developed and allow fire penetration.
4. Combining the borate epoxy to fiberglass cloth probably would be too thick and interfere with the battery contacts, but highly effective. Not tried yet, so it is possible that it would work just fine as a battery compartment liner. (Notes: sand plastic first before epoxing. Super glue works okay as a epoxy plastic primer. But I suspect a superglue ignites at 450F per googling, but need testing.)

5!! This is the fire testing result of several aluminum foils! The thin Dollar Tree foil is crazy flammable, when lit from the edge! The whole piece rapidly goes up in flames. Trying to lit this foil from smooth unbroken side, doesn't ignite....None of the thicker foil brands ignite this easily. In fact, only the back of the foil tape would ignite.

6. Covering the edge of a battery compartment (that ignites easily when untreated), with store bought foil tape (flammable glue) it tested fire resistant for a good 20+ seconds. Then, using foil with borate epoxy as adhesive, tested for 40 seconds-looked like the foil added 20 seconds before relying on the borate epoxy. Thicker foil is better, however, a thicker foil specification means fiberglass cloth may mean a better choice.. And I have yet to see if I can borate epoxy some fiber glass cloth down, without interfering with the 18650 electrical contacts. 
6. Found a year old piece of dried silicone1 caulking. Unfortunately, it was crazy flammable still. So, its resin is totally alien to the silicone that the chinese headlamps use as a firewall.
7. The old dried Silicone 2 is still crazy flammable. The ash of the burnt up silicone 2 offers no fire reducing char, unlike the silicone coaster burn char, as the fire tests showed. 

So, beware of Dollar tree foil (highly flammability) and Home Depot ionization fire detectors. Also, the silicone caulks will never become flame resistant on their own by drying out over a long time.


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## PhotonWrangler (Dec 27, 2016)

I winder if it's worth testing Sugru.


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## degarb (Dec 27, 2016)

PhotonWrangler said:


> I winder if it's worth testing Sugru.



I see it on Target website. . Never heard of it before. 

My lights use those 18650 spring contact with the flammable black plastic body. . I have played making my own 18650 holder, with a flakey result. . Testing a borate glue painted over the plastic China 18650 holder, did interfere with the 18650 positive contact on first light I tried. . So, tenuous is the spacing of this design. So, still unsure how to retro fire grade these lights. . And still unhappy with the 2s18650 holders I have purchased. They really need springs on both sides, be designed for protected cells, and be fireproof. Or enough overhead for some fireproof tape treatment.

Sugru...


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## PhotonWrangler (Dec 27, 2016)

You can find Sugru at Sparkfun, Adafruit and MicroCenter.


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## degarb (Dec 28, 2016)

Sugru has way better adhesion, as seen on youtube, than silicone caulking. . 

A peek at the msds list all ingredients by percent. . Unless I read wrong, 25 percent unlisted. Wonder if that part is a food (corn flower) , so doesn't need declaration.

Sugru Composition/information on ingredients
Declarable components Conc
(wt%)

Methyltris(methyleth￾ylketoxime) silane

3-Aminopropyltriethoxy￾silane

Ketoxime functional
polydimethylsiloxane

Talc, etc. all. 

Talc, respirable dust: WEL: TWA 1 mg/m3.
Barium sulphate: WEL: TWA 10 mg/m3 (inhalable fraction), 4 mg/m3 
(respirable fraction).
Silica, amorphous: WEL: 8 h TWA, 6 mg/m3 (inhalable), 2.4 mg/m3
(respirable).
Talc: 
Denmark TWA 0.3 mg/m3, STEL, 0.6 mg/m3 (respirable aerosol); 
The Netherlands TWA 0.25 mg/m3 (respirable aerosol); 
Finland TWA 0.5 fibres/cm3;
Sweden TWA 2 mg/m3 (inhalable aerosol), 1 mg/m3 (respirable aerosol); 
Hungary 2 mg/m3 (respirable aerosol); Spain 2 mg/m3 (respirable 
aerosol).
Barium sulphate:
Germany TWA 4 mg/m3 (inhalable fraction), 1.5 mg/m3 (respirable 
fraction); 
Spain TWA 10 mg/m3 (inhalable fraction).
Silica, amorphous:
Germany TWA 4 mg/m3 (inhalable aerosol);
Denmark TWA 2 mg/m3 (inhalable aerosol), STEL 4 mg/m3 (inhalable 
aerosol).
2-Butanone oxime:
Germany TWA 1 mg/m3 (0.3 ppm), STEL 8 mg/m3 (2 ppm);
Denmark TWA 25 ppm (provisional).
(3-Aminopropyl)triethoxysilane: 
Finland TWA 28 mg/m3 (3 ppm), STEL 55 mg/m3 (6 ppm).
BS EN 14042:2003; Workplace Atmospheres; Guide for the Application 
and Use of Procedures for the Assessment of Exposure to Chemical and 
Biological Agents, or specific national equivalent.
Barium sulphate: PNECs: PNECs: freshwater, 227.8 mg/L; intermittent 
release, 21 mg/L; sewage treatment plant, 50.1 mg/L; freshwater
sediment, 792.7 mg/kg dry sediment; soil, 207.7 mg/kg dry soil.
Other: human health
(DNELs, DMELs)
Other: environmental
(PNEC)
Barium sulphate: workers, long-term exposure, systemic effects, 
inhalation, 10 mg/m3; workers, long-term exposure, local effects, 
inhalation, 10 mg/m3. General population, long-term exposure, systemic 
effects, inhalation, 10 mg/m3; general population, long-term exposure, 
systemic effects, oral, 13 000 mg/kg/day.
Silicon dioxide: DNEL: worker, long-term exposure, systemic effects, 
inhalation, 4 mg/m3.
P


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## PhotonWrangler (Dec 28, 2016)

It dries to a surface texture that feels like hard rubber. It can be sanded or filed when dry. I've used it on a couple of tool handles.


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## degarb (Dec 28, 2016)

Please, kindly take a lighter to your sugru handle. Would you be such a dear. . I am getting test fatigue. 

I did try this morning to make my own version of sugru by mixing corn starch to silicone 1. Making a putty pancake, then using amazing goop glue as a syrup and folding it in, repeatedly to mix in. . I doubt I got the same stick though amazing goop is amazing. Will wait to see if cohesion is compromised. 

I did burn, this morning, some pvc pipe. . It burns nicely in heat, doubling the flame volume and heat. . Once the heat removed, flame goes out. . So, on own fire won't spread. I would imagine it would work synergistically with a flaming 2x4

Almost ordered 3 dual ionization fire detectors, yesterday , before realizing they didn't mean dual technology sensor. . Though dual ionization sounds better, but they don't elaborate on how. 

AlsoI am wondering if any lithium explosion experts here to dispute or verify my youtube observations . . Failure can be caused by overcharging (a frightful, classic bomb pop, but easily avoided), a direct short (20 second warning hiss, then 30 second of blow torch, then minute of flames). I assume puncture, over discharge shunts, cause same style failure as a short. . The stove top thermal runaway:as I recall (6cell laptops in this video, I am guessing.) , much like the short. 

A pop, scares me the most. 

There is a video for some F-500 something lithium fire encapsulation product. : https://youtu.be/Uex_O2TtTDw
18650 owners, have spare underwear available before watching this video.


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## PhotonWrangler (Dec 28, 2016)

Just tested it by holding the end of a Sugru-coated tool handle in a candle flame for a minute or so. It did NOT ignite, nor did it seem to melt. It did turn black with a small amount of grey-white ash at the very tip of the tool handle, but absolutely no flame. It did emit a thin trail of smoke, and section 5.2 of the MSDS states thi*s:

5.2 Special hazards arising from the substance or mixture*
The product is not flammable, but will decompose if involved in a fire,smoke, and toxic fumes and gases.

So it won't burn. Just stay upwind of the smoke.

After wiping the ash and discoloration off the tool, the Sugru held up surprisingly well.


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## degarb (Dec 28, 2016)

Do you know the best source for Sugru? Any sugru mines in NEO?


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## PhotonWrangler (Dec 28, 2016)

In stock at MicroCenter. You'll find it in the hobby electronics section, north wall. You might also check any hobby shops in your area.

Check the date on the package before you buy it. Sugru has an expiration date.


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## degarb (Dec 30, 2016)

Thanks, PW. 

I did a couple more tests to save a life, before I do anything of material value today. Also, some concerning results to report and document, before I forget:

1. Firstly, (and probably, most urgent concern) I found a spare unopened ionization detector in basement. I put 3 foot above me head, but even this one is not tripping during my firetesting. I even set a tub stopper on fire and blew it out for more smoke- a few inches underneath the detector--, and nothing!!! Apparently, only my wife's burned Italian cooking can set these detectors off. These two are single ionization detectors. Upgrade thoughts: dual ionization are cheap, but possibly no better. I haven't yet seen a sub $10 photo/ion detector.

2. While it took 48 hours to harden, the added borate to traditional steel reinforced JBWeld epoxy glue, did make it fire resistant. And, I do not see any brittling of the dried product, as I do in the 6 minute epoxy. Just one test, so far.

3. Adding borates to Siliconized acrylic caulk, waterborne polyurethane caulk (which I now suspect as having silicone additive), silicone 2/1 caulk, amazing goop, all were successes in creating a fire retardant coating. I didn't measure the ratio; but suspect 2 parts borates to 1 part resins, may have been many of the formulas. Though only the epoxies and silicone type 1, didn't become crumbly. However today, I failed to make a simple acrylic waterborne industrial enamal (multisurface acrylic) fire retardant. a 1:1 ratio borates to paint didn't do it. Then I tried 2:1, doubling the borates, it still would alight. I am trying 3:1. However, even at 1:1, the normally flexible coating lost flexibility.... Now I have burned off enough paint from wood in my time, so I should know better. Latex paints are very flammable (and soften with low heat) when dry and cured, while oil based are very heat resistant and hard to burn off. I need to test silicone alkyd or plastidip paint. Plastidip is probably easier to buy, and may be flexible. 

4. Making a mix of borates in boiling water, damping/soaking fabric in it, even briefly, works very well to fire retard. Works on paper too. Yes the paper is consumed by direct flame, but cannot burn on its own. Borate infusion does have a stiffening effect on the paper and fabric. However, due to failure of #3, not sure of a good way to seal in the borates, as yet. Maybe someone else has, and no hits on it yet. So, I would imagine any fabric that moves around will shed the borates over time. So, without sealing it in, there would need to be a recommended reapplication schedule. Though this requires direct testing to determine... Also, the stiffening would reduce water absorption (as in the wood article) and rot. I know I lost about $400 in outside dropcloths over last winter, because I had too many piled together; by spring, most had rotted away.


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## PhotonWrangler (Dec 30, 2016)

Degarb, you might want to get a can of smoke detector tester spray for that detector. You can conduct a more thorough test using this without stinking up the house.


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## degarb (Dec 30, 2016)

PhotonWrangler said:


> Degarb, you might want to get a can of smoke detector tester spray for that detector. You can conduct a more thorough test using this without stinking up the house.




What about incense? The detector spray-at $10-, seems better, after one buys a dozen or more to test.

I set fire to a battery holder, let it consume a cm2 and waived the black smoke directly under the detector; and, after about 2 minutes the newly opened single ion detection alarm went off. 

I need to test the upstairs ones (with more than the button). Gonna have to whip up a batch of french bread, while reading cpf.


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## degarb (Jan 3, 2017)

https://youtu.be/Y2WaoQJIaIc


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## degarb (Jan 4, 2017)

Leather fire index?

https://youtu.be/YieO7S2V5hU


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## degarb (Jan 4, 2017)

https://www.google.com/url?sa=t&sou...wIXICUqvoTzEFJF7Q&sig2=ngnXB7ZhpPwkKUX1e3bfvA

Leather has a flame spread rate of 10, according to this PDF. I think under 25 is recommended target, but don't yet know how the scale translates in real world. Especially, with lithium fire. Except over at fire forum a Ladies leather purse does well in a vape explosion,as far as one can tell from a video.

During search, chlorine us one of the few flame retardants, which is why PVC self extinguishes when flame removed.

Did recycled cellulose insulation flame test myself last night. Burns great, but leaves a flame resistant char, not unlike my borate treated rag. My concern was the shrinkage as it burned up, so would need a lot to work as a firewall.

Chorine powder at a spa store....though yet time to try magnesium hydroxide. Or do I mean manganese hydroxide. Oh well, what's in one letter.


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## degarb (Jan 4, 2017)

Took out me propane torch tonight for most promising materials. There are things you can learn from butane lighter that you cannot see with propane.

I first tested bare fiberglass cloth. Unlike the butane test of 60sec with barely a scorch, it popped a hole through in a fraction of a second. So I layered five layers, which the torch successively melted through in a half second.

Then I did leather work glove, didn't burn with either butane or propane blow torch. So, I put my hand in glove that loosely fit, so had some air insulation. Direct butane for 30 seconds before had to remove hand. Only black scorch on glove.

Holding the blow torch to center of silicone coaster, no pentration in something like 30 secs. Not bad.

I made a fiberglass sandwich of one mm thick borated silicone caulk. Lightly covered the outside of the sandwich with this borated rubber. The blow torch could not penetrate. Woo,hoo!

Torching some gutter flashing with the propane blow torch, creeped me out. You could, at times, almost see the metal alight. In theory it should melt. But , so should the caulk. Just a matter of time, based on specific heat and heat reflection/penetration.

Will try single ply coated fiberglass cloth tomorrow. Also, borated tripolymer v. Silicone 1. Nothing exciting. 

I fear leather is too expensive for bag making I know posting here, just caused the market value to rise higher. I know I had two wornout leather coats in garage last year... Wonder if alligator skin is flammable...My wife wonders if a barn burned down, would the cows be fireproof? Silly question,as the barn couldn't burn down with all the free milk around. (I , a long, long time ago, actually used a jug of milk from customers refrigerator to extinguish my drop cloth, since on the prior job, my fire extinguisher was used up putting out the electric box the erupted because water got into plug. I kid you not. My hands were not fire proof,took two weeks to heal, but I got new skin.)


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## degarb (Jan 4, 2017)

Oh, forgot the flame test of stucco five years prior. Unfortunately, pressure washers aren't as flame resistant. 

I rented a brand new $3000 pressure washer. Apparently, some missing gas o ring and a worker too scared to use the washer's own water on a gas fire. I came back to scorched building up to fourth floor, some toasted electric wires being repaired already,and was able to return a pressure washer that looked like a melted marshmallow . If they complained about its condition, I would have probably went on the offensive, as most likely a defective product. But who will ever know for sure. Could have been flammable water from fracking.

Plus one for genuine stucco. Yet to burn test Dryvit. Give me more time.


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## degarb (Jan 17, 2017)

My last fire test: two 2.5 inch x .75 inch rectangles of aluminum flashing. One half coated on both sides with 1mm thick Shermax waterborne elastomeric siliconized caulk mixed with 2 parts borax/boric acid. Held with pliers. The untreated aluminum melted in under 8 seconds with a blow torch, while the treated aluminum didn't melt or catch fire in over 2 minutes of the blow torch. 

I intend to attempt my own 2s18650 headlamp battery holder. Despite this test, I feel the 40 cent galvanized metal flashing is the way to go. I am thinking a 180 degree bend around an 18650, use dremmel to insert flat copper conductor epoxied and insulated. Then use a spring or wing nut to press the conductor in place. I suspect I can use the borax caulk to fire and electrically insulate, and jiggle proof fit the cell. I have not settled on best method to press the contacts into the cell. . I am leaning toward putty epoxy bolt and wing it tighten. My ultimate goal is to fully fireproof and insulate the cells as to not only protect wearer, but any bookbag and neighboring contents. I need downpour rain proof, not submersion . I doubt if the thin galvanized metal will be too heavy, compared to the aluminum flashing. 

My first test will be to "taco" a single 18650 for a one handed volt meter tester. On this one, maybe just cut galvanized flashing exactly to length of protected 18650, taco wrap 180 degrees. Attach my copper 9 mm wide 90 deg electric contacts, epoxied on bottom of taco. Wrap band of elastic horizontal around taco for support and as a spring. Solder my 1 to 8 series one square inch hobby meter. Keep beside my chargers a a faster way to test voltage onto and off charger. . I am aware this meter sucks for accuracy, but may alert to alarming high or low results. .... This could be made of wood, which would make for more stability, though less portability, along side 50 other tool box items.


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