HiTek color change overnight

[kevin c]

227839

The dull, sort of chalky look is what happened to some of my boolits after the second coat (prior to baking) when they were left on the drying screen overnight out of doors.

There were two stacked racks left out, both second coats from the same batch of coating. The first coating and baking went fine. The second coat went on fine, with all the casts having a nice glossy surface, but the next day there were shiny coated boolits on the top rack (those on the right in the image) but dull ones were on the lower rack (those on the left), mainly those on top of the pile (the ones underneath those were shiny), and mainly on the upper exposed part of the boolits.

The coating was my standard mix of 20 grams in 120 ml of acetone, about 5 ml for a weighed five pounds of casts. Each five pound batch was spread out for the initial drying, and then scraped together in a pile left in the screen. No contact between the top and bottom screens, and the casts were dumped just barely wet. No rain overnight.

After baking the second coat the dull casts were back to shiny, and all have passed the wipe and smash tests. I haven't shot any yet.

So, I'm not sure what caused the change in appearance. My guess is condensation, though why it affected only the lower rack i really don't know. I'm pretty sure it wasn't liquid coating dripping down from the top rack (I don't think I have ever dumped really wet).

It seems, with the normal appearance post baking and the passes on testing, that there was no harm done, but I still would like to know what happened. Any thoughts?

[Stephen Cohen]

I have had this happen in damp weather and using a near empty bottle of acetone, I put it down to water being sucked up by the acetone. I found as you did once they were dried properly the colour was as it should be when baked. Regards Stephen

[Ausglock]

Moisture out of the air has cooled on the bullets. no big deal. still bake and shoot fine.

[Shingle]

Why are you leaving them outside the humidity is your problem I'm in Louisiana you don't leave anything useful outside.

[ioon44]

I have had this happen after less than 2 hours of being set out side to dry, after baking them the color was fine.

[kevin c]

Thanks for the replies!

HiTek works well for me, but while I suppose I shouldn't mess with what works, I do want to know how rigidly I need to adhere to my "regimen" and why.

Previously I coated in my unheated "basement" (I live in a hillside house on stilts, so my workspace is actually above grade) without much problem. The solvent smell got in the house, though, so I took my operation outside to the deck, where I figured the extra warmth and direct sun would help the drying. I'd originally left the casts indoors overnight, to be sure that they were dry. I found with the outdoor outdoor sun drying in warm weather that overnight wasn't necessary. I didn't think that leaving them out overnight would be a problem.

And it turns out that, despite the odd appearance, it really isn't. Thanks again for everyone's comments!

[ioon44]

I dry my coated bullets out side on a deck in full sunshine and after 30 min the bullets have reached 140 deg F and are ready to bake.

[kevin c]

I dry my coated bullets out side on a deck in full sunshine and after 30 min the bullets have reached 140 deg F and are ready to bake. It's good to know that a short drying period can work. That'll shorten my total time to twice coat one batch of casts by a lot.