Painting a knife blade

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rincan

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I am looking to paint a knife blade and am wondering what my best options are for durability and cost effectiveness. I have seen cerakote but since im from Calgary it would cost me $67 for a 4oz tester including shipping. I also saw the less durable and less expensive brownels aluma-hyde but they do not ship the paint to Canada so that option is out for me.

Does anyone have any suggestions for me or is my only option to bite the bullet and go for the cerakote?

Thanks in advance guys and gals!
 
Do you mind a very inferior coating? If not, use header/bbq paint. If you want durability and chemically inert, go with Cerakote. If you're selling there's no paint option imo. You'll need to adjust your pricing accordingly, but you aren't doing right by your customers by using paint. Just my opinion. :eek:
 
the knife is for myself so selling isnt an issue. so how do knife companies do it like my kershaw boot knife is painted and not bad? i know you might not know this i just wonder how they paint and get decent durability do they powder coat or something?
thanks for the tip tho
 
One thing to be aware of with Cerakote is that you need quite a lot of equipment to apply it properly, most of which a small shop won't have. To apply Cerakote properly you'll need:

* Very clean compressed air supply (was using 2 filter/driers one after the other, and a dessicant drier just before the gun)
* Sandblasting equipment, with very clean sand (sand that's been used with oily parts will ruin your finishes)
* Good quality HVLP spraygun (small ones can be had pretty cheaply now if you don't have one, like $40-$50) the gun also needs to be very clean
* Decent spraying skills
* An oven large enough to bake the knife without touching any part of it (I used a toaster oven turned sideways)
* Very clean dust free space to spray in

If perfection is not required in the finish then the cleanliness issues are probably a bit less important, except for the air and sand. When I was doing Cerakote my process was basically:

* Finish the blade to clean 220 grit overall
* Degrease blade in ethanol bath
(Handle blade only wearing latex/nitrile gloves from now on)
* Sand-blast blade with 80 grit sand at 60PSI
* Heat blade to 300ºF for 1 hour, to off-gas any volatiles or oils that are on the blade.
* Decant Part A & Part B into glass measuring tube using plastic funnel (polypropylene)
* Stir, then filter with fine automotive strainer
* Spray with HVLP mini gun running at 35PSI with on-board air control wide open. 2" wide fan at 6" distance, very fine atomization. Inline desiccant drier on air-line.
* Spray went on so it was wet initially, then dried in about 15-20 seconds after spray, 2 thin coats
* Bake at 250ºF for 2 hours

I've done quite a few blades with Cerakote, and quite like it, but for me in the end it wasn't worth it because once the coating wears off it exposes the sand-blasted steel underneath which then rusts fairly easily. I haven't had any issues reported from my customers, not have I seen any real issues on my personal knife, I just wasn't really sure that it was worth the hassle. The other issue for me was that because you have to coat the blade before attaching the handles that takes away your opportunity to grind the scales and tang flush, which meant the fit and finish was always slightly less than perfect. Not a deal breaker, but overall I decided it wasn't the right finish for all my knives.

I think from what I've seen though that Cerakote is the best overall option for a non-glossy black finish. If I was looking for just the best black finish regardless of gloss then I'd likely try to go for a DLC coating, if I could ever manage to find a decent place to apply it!
 
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the knife is for myself so selling isnt an issue. so how do knife companies do it like my kershaw boot knife is painted and not bad? i know you might not know this i just wonder how they paint and get decent durability do they powder coat or something?
thanks for the tip tho
 
Sorry for the double post! but thanks for the great info! it does sound like quite the set up to do a few knives with an overall slightly above average performance. The DLC was my first choice but like you i cant find a good place to apply it.
 
You can have your blade powder coated. You might have a powder coater in the area.

I powder coat all the time and it is very strong and tough.
 
A bunch of companies (benchmade included) use Cerakote, it's nice because it goes on very thin and doesn't round off the nice sharp detail in your blade.

Many other companies use powder-coat finishes on their blade, ESEE for example. Powder-coating is tough as well, but mainly because it's quite a thick coating usually. You might be able to organize a thinner coating with the powdercoating place if you chat to them.

Many of the high-end black blades are not painted at all, instead they're 'coated' using a Physical Vapour Deposition process like "Diamond-like carbon" or "Titanium carbon nitride (TiCN)".

I think of all the black finishes I've ever seen TiCN is my overall favourite. CRKT used it on some of the original M16 knives that they made and that coating was the toughest I've ever seen. I opened multiple soup cans with that knife and they didn't even touch the coating. Only thing that ever scratched it was a mishap on the sharpening stone.

The downside of TiCN for knifemakers is that it's applied at around 900ºF, which is much higher than the tempering temperature for most of our steels, making it incompatible. Diamond Like Carbon (DLC) is applied at a much lower temperature of around 390ºF which makes it more useful overall.

Finding a coating place that can do consistent colors in either of the 'black' PVD coatings is hard though, often times a normal industrial coating using those processes will have many colors in it, almost like an oil slick. I still haven't found a coating applicator that can do pure black in either of those coatings.

Which leaves paint as the only real option. Cerakote is top of the stack there, with powder-coat or Duracote running in second. In all cases a bunch of careful prep needs to be done in order to get decent results.
 
Ok so here is another question. I might give this a try to see how it holds up but if anyone has experience with it id love to hear it. I made some micarta handles the other day and have left over epoxy. If i dyed the epoxy, west system has a number of options to do so, do you think that would hold up?
 
rincan said:
Ok so here is another question. I might give this a try to see how it holds up but if anyone has experience with it id love to hear it. I made some micarta handles the other day and have left over epoxy. If i dyed the epoxy, west system has a number of options to do so, do you think that would hold up?
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I actually tried this a little bit just the other day. I acid etched a blade and then coated it with West Systems. Applying with a brush it came out ugly and lumpy as West Systems doesn't flow as much as an actual paint would.

Realistically I think you'd have to thin the epoxy with solvent and spray it on to get it to be even, but I think it could work well if done right. Would still be better to sand-blast before applying the epoxy to make sure the epoxy has something to bite into.
 
good to know! what about painting on the epoxy decently thick and then hand sanding it smooth?
 
AVigil said:
You can have your blade powder coated. You might have a powder coater in the area.
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That's my advice as well, especially if you only need a couple blades done. When I needed it, I found a small local shop that normally worked on parts for race cars and snowmobiles. It was very affordable and turned out very, very tough. They can get lots of different colors and provide either a dull or glossy finish.

rincan said:
good to know! what about painting on the epoxy decently thick and then hand sanding it smooth?
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Good luck getting the air bubbles out.
 
Does anyone know what Becker uses to coat their knives? What ever it is, it's pretty tenacious. If I were to guess I'd say it's powder coating of some type but it has really strong adhesion to the blade.
I have a BK16 and before I stripped it down, I took some sandpaper and hand sanded the rough coating down quite a bit. I really liked it with the sanded coating but eventually used chemical stripper to completely remove the coating from the blade (I left the tang coating for corrosion protection)

The coating on my friend's Scrapyard Regulator also seemed similar to the coating on my BK16, a thick rough coating. I'd have to check with him to see how the coating has held up on it but I think that with Busse's reputation the coatings that they use (Busse/Swamprat/Scrapyard) would need to be exceptionally durable.

The more I think about it the more I think the best powder coating you'd want for a hard use blade would likely be one designed for engine blocks or undercarriage where high adhesion and abrasion/impact resistance are key. If you can find a custom car or motorcycle shop in your area you might be able to talk to their powder coat guy. I'd think that a custom bike shop would be your best chance to make a friend who could coat a blade the next time he's coating a frame or motor.
 
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james terrio said:
Good luck getting the air bubbles out.
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Easiest way to deal with any air bubbles is to make a very quick pass over the top of them with a propane torch. You can get perfect surface finishes on epoxy castings and so on using that technique... You don't have to 'cook' the epoxy, just very quick swipes with the torch and the heat bursts all the bubbles.

I think thinning and spraying is overall more likely to work though.
 
Very interesting idea with the epoxy! Curious to hear about your results if you try it.

About Busse, I've read that they apply a coat (of something?) before their top coat, but have also read that it's just decarb. No idea what is really going on under the top coat. I believe when the owners remove it down to bare steel they use chems for the top and abrasion for the under coat. They also use ferric chloride to deepen the etch before coating removal, the top coat is used as the resist.
 
I use Krylon Ultra Flat paint on my Ka-Bar. If its just for you, it should be fine.
 
FullyTorque said:
The more I think about it the more I think the best powder coating you'd want for a hard use blade would likely be one designed for engine blocks or undercarriage where high adhesion and abrasion/impact resistance are key. If you can find a custom car or motorcycle shop in your area you might be able to talk to their powder coat guy.
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That's exactly how I found the guy who did it for me. He normally worked on exhaust systems and frames.
 
I only use stainless steel but for those of you using carbon steel I would recommend contacting Sandstrom Coating Technologys. Phone 1-800-747-1084. They make a baked-on moly coating which might be perfect for knives. I'm not sure if it is food grade but they can tell you. Years ago I sold the stuff and it worked extremely well for corrosion protection on fire arms.

Tim
 
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