# Cerakote vs Duracoat vs Molyresin



## will (May 13, 2011)

I am thinking of trying a different type of coating for some of my work. I have done a lot of powder coating with a lot of success. The one disadvantage is the thickness of the coating. 

There are a few gun coatings out there, these three are 2 part coatings, in some cases also baked at 300 degrees.

Has anyone compared these three? 
Any feeling as to which is the 'best' ?


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## Yoda4561 (May 13, 2011)

I've used molyresin, and I can vouch for the product quality. Very thin, very hard, and on a properly prepped surface extremely difficult to chip off. It's also a single part coating, just shake it VERY well before applying. I've found it to have an edge on gunkote durability wise, but I think that has something to do with the different colors I used, some are more durable than others. 

The other products I haven't used, but I did a few weeks worth of research on all of them before going with Norell's Molyresin and some Gunkote (also a "moly resin" and very similar). Duracoat and cerakote are both two part products. There are oven drying and air drying versions of both, with different properties.

Duracoat is basically a heavy duty industrial finish, maybe it's custom formulated but some folks with good reps who have used it, state that it's very similar to sherwin williams Polane in practice. It'll go on relatively thick, and is softer than cerakote or molyresin, but should have better adhesion on a variety of materials and can be air dried (takes a week or two for full cure). They also have a product called Duraheat, which is the high temperature oven cure version. Neither is known to be lubricating, and the air dry duracoat in particular shouldn't be used on tight tolerance moving parts or threaded areas. 

Cerakote goes on thin like the moly based resins. I'm pretty sure the ceramic portion is hexagonal boron nitride , which is naturally lubricating and works similarly to graphite or moly. (not to be confused with cubic boron nitride, an abrasive). Going by paper specs it should be more durable as well, but there have been some reports of premature wear here on cerakoted flashlight parts. I don't think there's been a verification of why, it may have something to do with surface prep on aluminum or overinflated expectations of what the finish is capable of. There's an air dry and oven dry coating, interestingly it seems the air dry is the high temp version, and the oven curing one has less high temp stability.


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## will (May 13, 2011)

They all reference proper surface prep. I think that the anodize used on flashlights makes it difficult for the products to adhere properly. To be fair, any coating used on something that gets banged around will chip or scratch.


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## Yoda4561 (May 13, 2011)

It's surprising how resistant they are when on a good surface. I attacked a knife blade I finished in Flat Black molyresin with a screwdriver and a hammer, all that did was burnish the finish and make it glossier where it hit. A brass cleaning brush didn't affect it at all.(edit: that was holding the knife in one hand and hitting it with the other, I'm sure if the blade was supported on a solid surface the coating will get damaged) The gloss Gunmetal Blue gunkote seems to be more brittle, and has a tendency to chip and powder off under impact even with the same surface prep. 

Edit: It is also less resistant than powdercoats to abrasive blasting, due to the thin nature a single pass with a blaster wil remove it without fuss despite how durable it is in practical use. I consider that a positive since it makes it very easy to refinish once it does get worn down a bit, or if you want to change colors later.

Also wanted to mention that bead blasting won't work well for any of them, they really need a rough abrasive blasted surface to adhere properly. 100 or 120 grit Aluminum oxide is recommended. I've used 220 grit and 150 grit, 150 works perfectly, 220 adheres fine but the finish will be more prone to chipping as there's less depth to the texture. Starblast, Silicon carbide, and other sharp edged blasting media works good too. I've heard that coal slag works fine, but I'd be concerned about residue with that, be sure to degrease after blasting (I like non-chlorinated brake cleaner) if you're using media that might have any kind of oil residue in it.


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## Codiak (May 13, 2011)

What impacts of these coatings to thermal insulation? I'm relying heavily on rapid heat dissipation in a liquid environment.


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## Yoda4561 (May 13, 2011)

Gunkote and Molyresin improve thermal transfer. This mostly applies to radiant heat emission though. Most paints and especially the very thin heat cured coatings that aren't ceramic based are a huge increase in radiant emissivity for heat compared to bare metal. 

In a flowing liquid environment you're relying on conduction, the moly coatings won't improve things much, but are so thin they won't negatively impact performance when applied correctly, they have questionable utility however. If you're trying to prevent debris in the fluid from adhering to the metal surfaces or provide an anti-corrosion barrier that's about all the good they'd do. I'd suggest using a gloss color as the flats can have a texture similar to 1000 grit sandpaper depending on how it's applied. 

The ceramic based 3400 series gunkote and Cerakote I'm not too sure about. As thin as they are I don't think it'll affect anything, but the thermal conductivity ability of hBN ceramic based coatings is questionable. I've heard both sides, the folks at gunkote seem to think it's not as good as their moly based product regarding heat, but hBN is supposed to have excellent thermal conductivity, so I'd lean towards it being fine as well. 

Depending on the fluid I'd avoid duracoat, it has comparatively weak chemical and heat resistance and isn't going to provide anything other than corrosion protection.


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## precisionworks (May 13, 2011)

> I've heard that coal slag works fine, but I'd be concerned about residue with that


It's pretty clean ... around here in Coal Country, it goes by the name Black Beauty :devil: Manufactured by Harsco Minerals 

http://www.harscominerals.com/BlackBeauty/

Their "extra fine" grade is pretty coarse, yielding a 1.5-3 mil profile. If it were Aluminum Oxide, that would be 36-50 grit.


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## Codiak (May 13, 2011)

Yoda4561 said:


> In a flowing liquid environment you're relying on conduction, the moly coatings won't improve things much, but are so thin they won't negatively impact performance when applied correctly, they have questionable utility however. If you're trying to prevent debris in the fluid from adhering to the metal surfaces or provide an anti-corrosion barrier that's about all the good they'd do. I'd suggest using a gloss color as the flats can have a texture similar to 1000 grit sandpaper depending on how it's applied.



anti-corrosion is all I'd need... and when you say the texture is similar to 100grit... does that include the improved gripping power?

Application for me is the exterior of a solid alum 6061 dive light...


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## Yoda4561 (May 13, 2011)

Codiak said:


> anti-corrosion is all I'd need... and when you say the texture is similar to 100grit... does that include the improved gripping power?
> 
> Application for me is the exterior of a solid alum 6061 dive light...


 
Similar to 1000 grit, not 100. It does improve grip, for that application you should use the Norrell's Socom flat black molyresin, and preheat the parts before spraying to around 120 degrees with a hairdryer or by preheating a bit in the oven, use light misting coats and this will yield the coarsest texture. Mask off the threads if they're part of the electrical path, if they aren't then go ahead and coat those too, no matter how coarse you spray it, it will burnish smooth given time. On the grip areas the coating should remain coarse for a long time since it's only contacting a soft glove or bare hand.


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## Codiak (May 20, 2011)

How do I prep a knurled surface for Moly Resin?

Do I still need to blast it?
Or should I avoid knurling all together?


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## will (May 20, 2011)

I was wondering the same thing. I have seen pictures of cerakote lights. It looks like the knurled area is still nice and sharp. This is the thread :
http://www.candlepowerforums.com/vb...s-and-shops...-lets-see-them!&referrerid=4688


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## Codiak (May 20, 2011)

will said:


> I was wondering the same thing. I have seen pictures of cerakote lights. It looks like the knurled area is still nice and sharp. This is the thread :
> http://www.candlepowerforums.com/vb...s-and-shops...-lets-see-them!&referrerid=4688



Some nice lights... and those first photos were very nice indeed.

It's clear I'll need to blast the smooth areas anyway so I'm buying a sander

But I've yet to buy a Knurler capable of 2" diameter material... sooooooo... do I spend the 50 bucks or not


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## Yoda4561 (May 20, 2011)

Codiak said:


> How do I prep a knurled surface for Moly Resin?
> 
> Do I still need to blast it?
> Or should I avoid knurling all together?


 


Blast it, 40 psi with aluminum oxide or starblast and it won't affect the dimensions or sharpness of the knurling significantly.


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## Codiak (May 20, 2011)

Thanks!


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## will (May 21, 2011)

Yoda4561 said:


> Blast it, 40 psi with aluminum oxide or starblast and it won't affect the dimensions or sharpness of the knurling significantly.


 
Cerakote recommends 80 - 100 mesh size.

Anyone know of a good source for the sandblast media ( read that as cheap )


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## Codiak (May 21, 2011)

Just pick some up at Harbor freight


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## vestureofblood (May 21, 2011)

I'm liking this thread already. I have been so close several time pulling the trigger on that Duracoat. I would be very interested to see how that and the Molyresin look and feel VS Cerakote.

I have seen a hand full of the Ceakoted lights. I am not that impressed by it. To me it looks like about 5 layers of a thick spay paint. The look of it reminds me of a freshly painted car that is in need of wet sanding to get the orange peel out of it.

So far I have only ever held one light in my hand that was significantly better than any factory finish. A customer sent me a drab colored type III hard anodized light that had an unusually thick finish on it. The color was flat and it was almost as if when you held it in your hand it held you back. Like gripping some 600 grit sand paper but with out the loose particles ( hard to explain) I have had other HA III mags since then that certainly didnt have that same effect though.


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## cmacclel (May 22, 2011)

vestureofblood said:


> I'm liking this thread already. I have been so close several time pulling the trigger on that Duracoat. I would be very interested to see how that and the Molyresin look and feel VS Cerakote.
> 
> I have seen a hand full of the Ceakoted lights. I am not that impressed by it. To me it looks like about 5 layers of a thick spay paint. The look of it reminds me of a freshly painted car that is in need of wet sanding to get the orange peel out of it.
> 
> So far I have only ever held one light in my hand that was significantly better than any factory finish. A customer sent me a drab colored type III hard anodized light that had an unusually thick finish on it. The color was flat and it was almost as if when you held it in your hand it held you back. Like gripping some 600 grit sand paper but with out the loose particles ( hard to explain) I have had other HA III mags since then that certainly didnt have that same effect though.


 

Cerakote goes on so thin yet covers very well. Typically if I lay it on heavy it's .001 thick. I have used most of the latest coatings and I feel the cerakote is currently on top. There was alot of unrealistic hype when it first started appearing on CPF. Bottom line is......it's a spray on coating that is very durable but can be scratched. 

My buddy beats up everything. We coated his EDC pistol in duracoat and it lasted a week before
scratches appeared and it looked like hell within 2 months. 3 months ago I refinished the pistol with cerakote and it has help up very well. No scratches and 1 chip where he smacked it into a steel work bench.

Mac


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## mag1kate8all (May 22, 2011)

i work in the firearm industry and i use duracoat on everything from guns to motorcycle parts if you let it cure properly and prep correctly its tougher than nails and really doesnt chip or scratch easily


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## cmacclel (May 23, 2011)

mag1kate8all said:


> i work in the firearm industry and i use duracoat on everything from guns to motorcycle parts if you let it cure properly and prep correctly its tougher than nails and really doesnt chip or scratch easily


 
I prep everything per manufacture guidlines. If you think duracoat is tough then you would absolutely love cerakote.

Mac


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## will (May 23, 2011)

I have been researching the various coatings. They all want the object to be coated to be sand blasted. Then completely cleaned and degreased. Finally, baked to evaporate any moisture left on the object. Only then can the coating be sprayed on. I have asked about the original anodize finish on most flashlights. I have been told to remove the anodize and get the light down to bare aluminum. Because these finishes are thin, even the threaded areas can be coated. But, I think I would try to leave those areas the way they are. 

Mac - did you sandblast your work first?

I have an old sandblaster in the back of my garage, Time to clean it off and create some small blast cabinet.

I am leaning towards Cerakote - partly for durability, partly for color selection. Molyresin looks like a great finish, but the colors are aimed ( pun intended ) towards the gun industry, Moly has a lot of Camo colors.


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## cmacclel (May 23, 2011)

will said:


> I have been researching the various coatings. They all want the object to be coated to be sand blasted. Then completely cleaned and degreased. Finally, baked to evaporate any moisture left on the object. Only then can the coating be sprayed on. I have asked about the original anodize finish on most flashlights. I have been told to remove the anodize and get the light down to bare aluminum. Because these finishes are thin, even the threaded areas can be coated. But, I think I would try to leave those areas the way they are.
> 
> Mac - did you sandblast your work first?
> 
> ...




All parts are degreased.....sand blasted with Aluminum Oxide....baked....then coated....then cured at 250f for 2 hours or 300f for 1 hour.

Mac


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## mag1kate8all (May 23, 2011)

cmacclel said:


> I prep everything per manufacture guidlines. If you think duracoat is tough then you would absolutely love cerakote.
> 
> Mac


 
im going to have to give cerakote a try


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## nbjly (Jul 6, 2011)

mag1kate8all said:


> im going to have to give cerakote a try


 
Agreed, I've Duracoated a lot of things. It's not that tough until it really cures, maybe just the way I mixed it but it was oven-cured. Seems like a year later it's a lot tougher. I just sent some items off to be Cerakoted -


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## wquiles (Jul 6, 2011)

What "air brushes" do you guys use when spraying moly resin or cerakote? Single action vs. double action, top feed vs. bottom feed, etc.?


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## Yoda4561 (Jul 7, 2011)

I use a single action, external mix Badger 350. If you want to do camo patterns and stuff, the dual action internal mix brushes are good, but they're also more potentially more maintenance and not as forgiving of lazy cleaning habits. That said you can get a dual action brush from harbor freight that's cheaper than my single action badger, made in china of course but for a knockoff of another major brand I hear it works quite well.


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## wquiles (Jul 7, 2011)

Cool, thanks. Based on your info I found this "very" good video explaining airbrushes - all of the basics 
http://www.youtube.com/watch?v=Aog6dNwydhg&feature=related


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