# My Air Compressor Upgrade



## darkzero (Nov 22, 2011)

I’ve been running a Craftsman/DeVilbiss 20gal twin cyl oil lubricated 125psi 7.1 cfm @ 90psi compressor for almost the past 15 years. It’s served me well as a mechanic (side jobs at home) for most things & still runs as strong as the day I got it. Then some months ago I got a Exair Cold Air Gun which the compressor can't even come close to keeping up with it (15 cfm). I piggy backed a 17gal tank to the Craftman which bought me a little more run time but the compressor is just too small.









I've always wanted to upgrade but it was not even a thought on my list of things to do. Then I came across a 60gal 240V single phase twin cyl single stage 130psi 12.85 cfm @ 90 psi compressor for $255. It was claimed to have not much use on it & I got it from a guy whose shop burned down. Luckily the compressor sat outside in a shed.

Yes, it is a HF compressor & normally I would never even think of buying a compressor from HF. But for $250 I couldn’t go wrong & could easily resell if I chose not to keep it. Then I learned that the larger US General branded HF compressor are made/assembled in the US & are made by ABAC/American IMC. They also make BelAire compressors, the larger Kobalts, & others. They are essentially the same identical compressors sold by BelAire. Tank is ASME certified, stamped Manchester Tank, pump is IMC made in Italy, 15A motor is AO Smith made in the USA (the newer motors are assembled in Mexico), & the pressure switch is Condor. 3450 rpm so it's not super silent but it's not much louder than my Craftsman so the neighbors might still not hate me yet.

Anyways, what’s important is that I am very happy with the purchase & knowing what I know now, I would have gladly paid full price for a new one. I would have loved to get the next model up (2 stage) but for home use I am more than happy with it's performance. And now I can use my cold air gun as it was designed to be. Last week I had to replace the ball joints & performed some other suspension work on my truck, the compressor did not even kick on once during the entire 3hr job using my 3/8" & 1/2" IR impacts.


Picked it up 30 mi away.







Running two Norgren FRs.







Got a Wika SS case liquid fillable gauge for a good price since it was not filled. Filled it with glycerin.












Used the extra Mason feet that I took of the lathe.







Added another ball valve for the drain.







Can't understand why they would use a M8 bolt for the drain! My Craftsman uses a 3/8" NPT plug which is reasonable. The drain is not in a good location & can make oil chages very messy. So I made a M8 to 1/8" NPT adapter to make an extension. Since the drain hole is now inside the M8 thread, the hole is even smaller now but at least I can extend it further out to avoid possible messes, I can deal with the wait. I added an 1/8" NPT nipple & cap which you can see further down below.

On the left is the adapter & on the right is what it started out as.







Took a chance & picked up a factory aftercooler for a similar pump also made by IMC for $22. Here’s the stock discharge tube (1/2” OD) & plastic air box.







There are predrilled holes for the discharge side of the head, just needed to thread them.












The aftercooler bolted right on.







But I had an issue with the gasket since the head it was designed for does not have the 1/2" NPT outlet.







So I got a reducing bushing, shortened & bored it out.

















Mock up…. Also picked up a Solberg Filter/Silencer & intake adapter to replace the stock air box.







A bit of paint, replaced the stock discharge tube with a 5/8” OD tube (aftercooler flares out to 3/4" NPT) & it’s ready to go. Running Amsoil ISO100 Compressor Oil.
















Over stock, I got about 120deg reduction in temp on the discharge tube at the check valve on the tank & fill time from 0-132psi was reduced by 5 secs. Not bad for an inexpensive piece of finned aluminum. Maybe later on I'll look into using a heat exchanger like the real big boy compressors or a coil of tube like Barry.


I’m still using the 17gal tank connected to the 60gal & is dedicated for use with the cold air gun. Running a check valve on the inlet & a Norgren Mini Regulator set to 60psi. I’m amazed how effective it works now that I can “really” use it.


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## darkzero (Nov 22, 2011)

I wasn’t happy with the conduit that was installed for my lathe, but hey I was getting charged by the hour. Since I was going to run a dedicated circuit for the compressor I decided to replace it all with EMT & run it myself.


Here’s what it used to look like.



























And after I replaced it all.

































Much better. I hated the old sloppy looking conduit.

As for Code. Of course safety is most important but I’m just curious if I'm legal? 

The wire I ran for the additional 240v breaker was with white & black wire instead of red & black like that was used for the existing 240v breaker. I used red shrink tape on the white wire where it terminated on the breaker & at the socket end. I read that this is acceptable. 

I used the existing ground from the panel & connected another ground for the second socket which I terminated in the square box where I made the drop for the compressor. So from the panel, there are four hots & one ground, then from the square continues on with two hots & the ground connected to the existing ground. I read that sharing a common ground is acceptable.

I placed camps within 3ft of each square and tube connector. The only termination I have is for the addition ground in the square by the compressor. All other wires are continuous but I left plenty of slack inside each square just in case. But do I have to mark the white wire red inside each square even though it’s continuous?

From the panel is conduit, I used a box to connect the conduit to EMT & for pulling the wire through. Is this acceptable?

The outlet for both the air compressor & lathe are 48” from the ground. Like the lathe I’m using a Nema 6-50 plug & socket but both 240v circuits are 30A 10 AWG. I guess I should be using a NEMA 6-30 configuration? The plugs I can always reconfigure the flats from vertical to horizontal & change the sockets if needed. Should I be concerned?

For the air compressor I’m using a square box with a socket but the lathe I’m using a plastic surface mount outlet under the motor switch. I think I may change it out later but is this acceptable?

Thanks


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## BVH (Nov 22, 2011)

Great find! I see you're "going green" by recycling the condensate....errrr....water into your garden!


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## gadget_lover (Nov 22, 2011)

I love seeing "lower class" machinery upgraded to Cinderella grade. That was some nice research that led you to this diamond in the rough.

Thanks for sharing.

Daniel


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## darkzero (Nov 22, 2011)

Thanks fellas! 

I hope the plants don't die. oo:

It was a fun project. When I picked it up I figured I could sell my Craftsman for $150-$200 so in the end for only $100 this would be a nice upgrade. Well in the end with all the brass, other air accessories, & wiring it was pretty costly. Still well worth it though.


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## precisionworks (Nov 22, 2011)

Nice compressor - Lowes sells that same unit for $500 






Be really careful with the bottom drain ... they normally come with a tiny 1/4" NPT threaded outlet. You can open that to a larger pipe thread but even if you stay with 1/4" NPT be sure to use either a brass or SS elbow, not galvanized. After about five years the galvanized elbow will rust through & let go in the middle of the night 

Nice job on the EMT. Surprised that anybody would run that much flex as most electricians run as little flex as possible to get the job done. Check with a local electrician on your questions as your local electrical code can be more strict than the NEC.


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## wquiles (Nov 22, 2011)

Great find and very well executed upgrade!


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## PEU (Nov 22, 2011)

Very Nice Will, the aftercooler seems to be small but time will tell if its OK or not 


Pablo


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## darkzero (Nov 22, 2011)

Thanks everyone!



precisionworks said:


> Be really careful with the bottom drain ... they normally come with a tiny 1/4" NPT threaded outlet. You can open that to a larger pipe thread but even if you stay with 1/4" NPT be sure to use either a brass or SS elbow, not galvanized. After about five years the galvanized elbow will rust through & let go in the middle of the night



Thanks Barry. I did not know that about the galvanized elbow. The prev owner did use galvanized for everything. But I did replace the galvanized elbow & 1/2 pipe with a brass elbow & 3/8 pipe. Is it just a the elbow to be concerned about? I have heard that it's not good to use brass with galvanized as the differences between the two metals speeds up corrosion or something, I forget. Is that true & should I replace the galvanized pipe & reducer with brass?

Just remembered I do have an extra stainless elbow like I used for my cold air gun, guess I should have used that.


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## precisionworks (Nov 22, 2011)

Will,

SS or brass should do fine. I had a galvanized elbow rust through after about five years - no surprise since that part is under water most of the time. And I always use my foot to open & shut the valve so that puts more stress on the elbow.


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## Morelite (Nov 22, 2011)

Nice score and nice work. As for the white live wire your fine as long as you cover the visible (inside all boxes) white insulation with any color other than green. I usually just use a wide sharpie but shrink tubing or electrical tape is just as good and all methods are accepted by NEC.


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## darkzero (Nov 22, 2011)

precisionworks said:


> Will,
> 
> SS or brass should do fine. I had a galvanized elbow rust through after about five years - no surprise since that part is under water most of the time. And I always use my foot to open & shut the valve so that puts more stress on the elbow.



Barry, sorry for not being more clear.

The elbow for the drain is currently brass. The only galvanized I'm using is the 3/8 pipe & the reducer that's connected to the brass elbow. I guess I should change them out to be safe anyway. I've never used galvanized on an air compressor before & connected to brass. They were just handy at the time.


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## precisionworks (Nov 22, 2011)

I think what you've done will work well as it is. There may be a tiny amount of electrolysis between the brass elbow & the galvanized pipe but those parts are thick and should last for years. All brass or all stainless might be a bit better but that really is splitting hairs.

Of course the very best solution is to run all Ti6-4


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## darkzero (Nov 22, 2011)

precisionworks said:


> I think what you've done will work well as it is. There may be a tiny amount of *electrolysis* between the brass elbow & the galvanized pipe but those parts are thick and should last for years. All brass or all stainless might be a bit better but that really is splitting hairs.



That's what it was! I remember someone telling me when I used to work at a dismantling yard but I couldn't remember what.

I used galvanized since it was on hand & I thought it might be stronger than brass in case the drain pipe got kicked or something (breaking at the 1/4 extension). But now that I look at it, I guess the brass would be the weak link. Well since I sized it so it doesn't stick out far I guess I should be ok. I'll swap the pieces over to brass. 

Thank you!




precisionworks said:


> Of course the very best solution is to run all Ti6-4



What a great idea! :devil: 

Please don't tempt me. 

I've got a problem.... I keep buying up surplus Ti 6-4 much faster than I can even possibly use it. Too good to pass up when I find those crazy deals. My small collection is growing, I've already got one tool box full, and just today I scored another eight 1ft 1" rods. 

I might find myself making parts for the lathe out of Ti. soon...


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## StrikerDown (Nov 23, 2011)

Great score there Will! I've been eying those compressorsfor some time. My 30+year old Montgomery Wards 1 HP compressor just keeps on humming along though!

I remember when you posted pics of your lathe wiring and thinking you hired a slug for an electrician!  I always found that flex runs over any distance took me as much time as EMT mostly because it's harder to stuff a fish tape and pull the wiring in, then theres all the extra clips. the time saved not bending isn't worth it, especially for longer runs. I think you are in much better shape now... looks professional, great job!

As far as being "Legal" Probably Not, unless you pulled a permit for the install! But who cares really as long as it's done safely! I don't usually get a permit... hell, never got a permit for my garage stuff! :devil:

I really need a bigger compressor! Especially for bead blasting my gun work! :sigh:


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## precisionworks (Nov 23, 2011)

> never got a permit for my garage stuff! :devil:


We installed a small building in another town about five miles away. I set a 20' pole, attached the meter base & disconnect, ran PVC underground as conduit for the 2/0 aluminum conductors, etc. (240v 3ph 200A service). City inspector came by a few months later & said we needed to get a permit. The owner was scared that the city would make him remove the building, wiring, etc. The inspector said not to worry, they just want the money


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## darkzero (Nov 25, 2011)

precisionworks said:


> There may be a tiny amount of electrolysis between the brass elbow & the galvanized pipe but those parts are thick and should last for years.



Thanks again for the advice Barry. I changed the pipe to brass today. It hasn't even been a month but with the water speeding up the electrolysis it was already starting to show rust where it joined with the brass elbow. As you said, might be years before something would happen but at that rate I now don't have to have that worry in the back of my head.




StrikerDown said:


> Great score there Will! I've been eying those compressorsfor some time. My 30+year old Montgomery Wards 1 HP compressor just keeps on humming along though!
> I remember when you posted pics of your lathe wiring and thinking you hired a slug for an electrician!  I always found that flex runs over any distance took me as much time as EMT mostly because it's harder to stuff a fish tape and pull the wiring in, then theres all the extra clips. the time saved not bending isn't worth it, especially for longer runs. I think you are in much better shape now... looks professional, great job!
> 
> As far as being "Legal" Probably Not, unless you pulled a permit for the install! But who cares really as long as it's done safely! I don't usually get a permit... hell, never got a permit for my garage stuff! :devil:
> ...



Thanks Ray. Yeah after it was wired up I hated how ugly it all looked & I knew I had to eventually do something about it. When the lathe arrived I quickly forgot it about as I was then spending the time & money on other "important" things. 

Man, can't believe you said Montgomery Ward! I haven't heard that in a very long time. Brings back memories such as Builder's Emporium. That was the only hardware chain store I remember in those days around here.


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## BVH (Nov 26, 2011)

darkzero said:


> Man, can't believe you said Montgomery Ward! I haven't heard that in a very long time. Brings back memories such as Builder's Emporium. That was the only hardware chain store I remember in those days around here.



How about Gemco and Fedco?


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## StrikerDown (Nov 26, 2011)

I've bought a bunch of stuff from those guys also! Between the three they are why I don't buy extended warranties also!


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## darkzero (Nov 26, 2011)

BVH said:


> How about Gemco and Fedco?



Gemco no but Fedco yes. Of course I was just a little kid back then. 

I still have one of those blue quarter holder key chains for Price Club. Used for "renting" a shopping cart, when it was returned you got your quarter back.


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## MorpheusT1 (Nov 27, 2011)

Very nice setup you have there Will 
And all the work that is put behind it, looks very professional.

Im green with envy...and that box full of Titanium.....Yum


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## darkzero (Nov 27, 2011)

MorpheusT1 said:


> Very nice setup you have there Will
> And all the work that is put behind it, looks very professional.
> 
> Im green with envy...and that box full of Titanium.....Yum



Thank you Benny


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## cmacclel (Dec 15, 2011)

I called up US General when my compressor had some oil leaking from one of the fittings and he said if they got hot they might do this. He also said they DO NOT recommend running synthetic oil which is what I installed when I changed the oil.

On another note the brass NPT tubing I had coming out of the tank broke after a few months so I changed it to steel.

Mac


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## precisionworks (Dec 15, 2011)

> said they DO NOT recommend running synthetic oil which is what I installed when I changed the oil.


All the high end rotary screw manufacturers as well as those that make industrial reciprocating compressors recommend synthetics. Many will double the warranty after a rebuild IF a specified synthetic is used. For recips a popular oil is Mobil Rarus 800: http://www.mobil.com/USA-English/Lubes/PDS/GLXXENINDMOMobil_Rarus_800.aspx

One issue that may arise with synthetics is that they will sometimes seep through an imperfect gasket seal, causing a warranty problem for the manufacturer. Not the oils fault that the manufacturer needs to do a better job machining & fitting their parts together 

A second concern is that synthetic oils will degrade both PVC air lines & the clear Lexan (polycarbonate) bowls used in filters & regulators. Lexan bowls are acceptable with synthetics as long as the bowls are metal caged.

Your compressor will run cooler & last longer with synthetic oils.


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## cmacclel (Dec 15, 2011)

precisionworks said:


> Many will double the warranty after a rebuild IF a specified synthetic is used.




I brought this exact thing up to the technical person I spoke to. I said the IR doubles the warranty if synthetic is used.


Mac


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## darkzero (Dec 15, 2011)

cmacclel said:


> I called up US General



Just curious, is it HF that you talked to or ABAC/American IMC (manufacturer of these compressors)? As far as I know US General is a HF name brand. I assume it was the 866 number you called that is on the the compressor? My buddy had some issues with his compressor & when he called the 866 number he said they were not very helpful & didn't sound very knowledgeable at all. I wonder who the people are for that 866 number?



precisionworks said:


> One issue that may arise with synthetics is that they will sometimes seep through an imperfect gasket seal.



Agreed, sythetic oils are known to be "slick". Generally it's not recommended to use synthetics in a "new" engine. I never used snythetic oil in any of the engine builds I have done for customer's. Only recommended switching to synthetic after the engine has been properly broken in. In some cases that could be as much (or more) than 20K mi before there are no more signs of blow by & burning oil is not out of the ordinary if it wasn't fully broken in. But this of course were automotive applications. 

My buddy picked up the same exact compressor as me just after I got mine, also used. But he wasn't so lucky with his, his was newer than mine. He had a leak between the valve body & later found out it was due to a missing copper seal in between the valve bodies. Even with a head rebuild kit, there were still leaks from in between the valve bodies (also used synthetic oil). Having these similar issues with thin modified head gaskets, I always use copper spray during assembly. I recommended my buddy to do the same & it fixed the issue (so far). The stock copper seal is super thin. Copper gaskets aren't known to seal well without the use of orings (requires machining) & any imperfections in the fittment of the parts will guarantee slight leakage.

I've been running Amsoil ISO 100 Synthetic in mine with no leakage at all so far. I've been monitoring it closely after what happened to my buddy. Hasn't been that long yet but if I run into the problems I'll be sure to report back here. I already have a head rebuilt kit on hand just in case. The valve bodies in these italian made pumps are known to be a hit and miss in reliability depending on how old they are. My buddy's replacement valve bodies had some slight differences than his originals.

To add, most single stage compressors are recommended to be broken in by running the pump the for about 30 mins with the drain open. I've heard for two stage compressors this same break in method is not as effective & must be broken in with pressure to put a bit of load on the pump. Generally rings need to be broken in with cycles of temp rise & cool down. I know it's not an internal combustion engine but I would think break in would be a similar practice but take longer to break in. Although mine was a bit used, I ran some break in cycles with the original oil just in case anyway.


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## cmacclel (Dec 15, 2011)

I spoke with a person at the 866 number which was the compressor MFG. I ran mine for 4 months before changing to synthetic. It seems to only weep oil if I'm really using it when sand blasting for an hour or so. Then again I most likely am pushing or over the recommended duty cycle.

Mac


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## darkzero (Dec 16, 2011)

cmacclel said:


> It seems to only weep oil if I'm really using it when sand blasting for an hour or so.



Thanks for that info. I haven't ran mine that hard yet, only a number of continuous cycles so far but no issues that I have noticed yet. With my old air compressor my die grinders required the most air & ran it hard but with this compressor I haven't ran them yet. But my die grinders are the quiter IR models generally used on production lines. They don't consume as much air as my cheap die grinder that I use with a cut-off wheel.


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## brianbucar (Jan 28, 2012)

thanks for the ideas.  

i have a 60 gallon craftsman tank that i got from the neighbor for free because the pump was bad. 

i bought the large 2 cyl HF pump (the one that goes on sale for 100$ here and there) and am assembling the compressor as soon as i get a 5hp+ motor. 

i plan on running non synthetic oil for the first few months or so to make sure that everything is seated and then ill switch to synthetic. 

the output of the pump is a soft copper tube fitting which i will plumb to some sort of heat exchanger in the same size as the copper and either use fittings or solder/braze it to the line that goes to the compressor. ill probably add a shroud to the large pump pulley as its also a fan to duct air over the entire assembly. 

there are some timer/solenoid assemblies that can be added to the bottom of the compressor tank to automatically drain the condensate from the tank after the motor shuts off. i'll probably build one of those as well. 


a few of my friends have the cheap HF compressors and have no issues with them as long as they change the compressor oil soon after the first run and then regularly after that. 

usually with harbor freight, if it works when you first plug it in, and you do some maintenance regularly, it will last fairly well. 

Brian


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## kuksul08 (Jan 29, 2012)

That is quite an upgrade and I can tell you do quality work. It's nice having the tools available to do the job right. The drain adapter is slick!


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## darkzero (Jan 29, 2012)

Thank you very much.

I got lucky & sold the 13 yr old Craftsman (I was mistaken, it wasn't 15 yrs old) for $200 a couple of weeks ago. So in the end it was a $50 upgrade (not including accessories, etc.).


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## darkzero (Feb 6, 2012)

Now that I no longer have a portable air compressor, I decided to finally install a hose reel, 50 footer. 















And the old belt would occasionally slap against the belt cover so while I had the cover off to modify it I decided to but a new belt on it.






While I'm at it might as well put them on everything else that had old belts that were "bumpy" from "setting in".


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