Wednesday, October 31, 2012

The paint test

You may remember I took a bayonet and painted it with header paint, to try out and see how it holds up.
Baking was done the other day.  Instructions say to bake at 250F for 30 minutes, cool 30, bake at 400 for 30, cool 30, then- IF the parts can tolerate- bake at 600 for 30.  600F would screw the heat treatment* on most anything I can think of, so after the second heat I gave it another 30 minutes at 400, then left it in the oven to cool.

No detectable smell while baking, so no worries about stinking up the house or annoying the hubby/wife/whoever while using the oven.  It's assembled, and I'm trying to decide on proper testing procedures.  I need to pick up a kitchen knife, something like an Old Hickory, and clean and treat it; it'd be a better shape for kitchen use.


*Most blade steels I'm aware of, 400F would be the lowest temp that would start to affect the hardness, unless they're tempered very hard.  If you're trying this on something you're worried about, I'd make the highest temp 375F; unless you're working with something odd, that's the temp at which you'd just begin to show the lightest trace of yellow on polished steel, and I know of no commercial blade tempered that hard.  Or anything else, for that matter, other than some kind of drill or something.

1 comment:

Anonymous said...

Firehand,
I have tested various coatings on headers and here is what I found... The very best is a ceramic coating commercially applied by PolyDyn coatings in Houston. They have many types of coatings for varying applications (anti heat, anti-friction) and apply them to turbines, piston engine components, NASCAR wheels, guns, etc. I'm not sure of their bake temps. Of course, that approach is expensive. JetHot also does nice work on headers.
I also did a side to side test of spray on ceramic header coating vs POR15 high heat paint with microscopic ceramic beads mixed in. The spray coated headers lost most of the coating after a few heat cycles, but the POR15 side lasted pretty well. With all of these, as I'm sure you know, surface prep is the key. All of this blather prolly doesn't mean squat about using it on a knife. Looking forward to your results.
Jim in Texas