Powder Coating 101 - Electrostatic Method

[fps_bill]

I tried powder coating some boolits today and had ok results. I had to turn turn the pressure to 30 psi to get my hf gun to spray powder which doesn't seem right. Are there any mods yo make the gun spray at lower psi? I also had serious flashing but I think that was because of the amount of waste I had from getting too close and blowing powder off of the boolits.

[Beagle333]

How much powder did you put in the cup? If you put more than an inch to an inch-and-a-half I find it takes more air to get it fluidized. And you should shake, tap against your palm, or flip the gun from side to side occasionally to keep it stirred up. If not those, we'll think of more suggestions to check on.

[ipijohn]

The hardware cloth will work.... once. What I'm curious about is how a user will get an electrical charge through his boolits after the first use. They won't be sitting on a bare metal screen anymore, unless the surface of it gets sanded completely every time. The boolits must be sitting on clean bare metal for the static charge to get from the ground clip to the boolit, or it isn't ESPC... it's just gravity spray.
It would be great if somebody has a technique, but I haven't seen it detailed yet.

I reuse the screen wire on the racks that I use to ESPC shoot and bake. By precisely placing the next load on the upainted spots on the screen, I have electrical contact. This is done using a loading block that is placed in exactly the same spot every time the rack is loaded. My gun seems to work best with the PSI set just south of 20 and I keep at least 1" of powder in it, I reload the gun every 600 boolits = 3 racks = one oven load.

[Smoke4320]

If you have the Harbor Freight brand gun take off the yellow washer looking defuser at the end of the gun.. Then spray at about at 45 Degree angle..
Go above/between rows so powder is attracted to side of bullets and top at the same time.. As beagle says keep lightly shaking the gun from time to time to make sure the powder is stirring up

[fps_bill]

Thanks. I may have had too much powder in the hopper. Hopefully my 500gr mold will get here and Ill get to try less powder with lower pressure this weekend.

[bangerjim]

Yes, keep it about and inch to two inches of powder in the gun jar and LIGHTLY bang the bottle on your palm as you are spraying. I use only 10-12 PSIG max! Powder should gently flow out in a light cloud.......not in a blinding heavy fog (as show on some of those lame Youtube videos) or in big heavy clumps.

You must maintain that fluidized bed in the bottle to get a good even coat. Same applies to the Amazon gun.

banger

[robertbank]

Up here humidity is always high unfortunately and I believe I read on this thread high humidity does not help things along. I assume that is what affects my spraying to some degree.

Bob

[Beagle333]

I have only noticed humidity affecting tumbling and not ESPC. I spray outside in my gravel driveway and have sprayed not long after a rain; in the fog; and after dark with dew all over the table; and it worked well. I think as long as you have static, meaning that you get a good 1/2" to 3/4" arc from any boolit to the tip of the gun, it'll make the powder stick, and I have never had the powder just fall off before I move the boolits to the oven.
ESPC might be troublesome to set up the equipment and tricky to move the boolits around for baking, but it makes a beautiful coat every time.

[robertbank]

Yes good to hear. Yes on the coating. With my truncated cone 9MM bullets I am sticking them nose face down into the nuts which works really well. I get a nice even coat over the driving bands and the olgive looks cool with light streaks of paint half way down from the bands. The temperature is going to be around 50F tomorrow, can you imagine this far north, so I intend to spend the day PCing a variety of bullets. I intend to use my nut trays, nuts up, with the 9MM nose down and some just on NSAF after coating in my paint bay I made out of a cardboard box and lexon plastic. I may also try my lime green on my 40 cal for fun.

Thanks for the help.

Take Care

Bob

[lka]

Caster a batch of 452 hp and hope to have time to pc them today

[lka]

Done! I like the blue, purdy bullets!

[lka]

Ps those aren't scratches, just reflection super shiny stuff.

[robertbank]

Very nice indeed.

Bob

[kryogen]

yeah, ESPC makes really nicely finished boolits. it's just too long to process compared to hi-tek though... shake 150 boolits 10 seconds, dump on a mesh tray, done... I've quit powdercoating completely. It worked, nice looking, no leading, too long to process.

[Beagle333]

If you are spraying multiple trays and sliding them into the oven and baking 10 mins only once while you are spraying a couple of more trays.... your oven size will determine which is faster, since the shake/dump has to be baked twice, and let dry each time between dump and bake. Both can be really fast if you approach it in a manner that maximizes output.

[robertbank]

With my trays using cartridge cases I estimate I will be able to produce 200 bullets ie 2 trays of 100 bullets every 10 minutes and should be able to maintain a production of 800 bullets every hour with an assistant to help load trays. The bullets will require one more sizing, an activity to be completed in the early hours of the morning or late evening. Even if I cut that production to 600 bullets per hour the speed will be ample to suit my needs. In the background is the need to cast bullets, smelt down WWs but I do that anyway.

With my method it will be like picking on a scab. You just keep at it overtime to produce the volumes I need. I donèt intend to spend hours and hours with shoulder to the wheel. That would mean the process has turned into a job aka work. I did not retire to find myself another job. This all must remain a hobby leading to my sport. Otherwise I will take up gardening (shudder).

Take Care

Bob

[lka]

I just do it because it's fun and a great skill to learn for the times ammo is hard to find. Actually the only ammo I buy these days is 22lr. And their purdy!

I took the red white and blue buck out the other day, shot 50 of them with no issue, odd chrony results though :/.

[kryogen]

If you are spraying multiple trays and sliding them into the oven and baking 10 mins only once while you are spraying a couple of more trays.... your oven size will determine which is faster, since the shake/dump has to be baked twice, and let dry each time between dump and bake. Both can be really fast if you approach it in a manner that maximizes output.

Yeah, the spraying just wasnt for me. It worked well though, glossy finish and nice results. I hate dealing with powder and transferring boolits one by one.
I prefer the shake and bake hi tek for ease of use... but that's just me.
ESPC boolits were better looking. And they werent leading.

[kryogen]

yup, I can fit 5 pounds in the oven every 15 minutes. double coated and baked, that's approx 600 coated boolits per hour that will be ready to load. But it's not really time lost, because you are probably reloading at the same time...
Right now I don't really need to have more than 600 bullets per hour. But you can always buy a bigger oven, I just don't really want to. Fine for me.
This has to be the easiest step of all my reloading. Dump 2.5 pounds in a container, drop 3ml, shake 10 seconds, dump on a tray. That's 150 boolits coated in 10 seconds... easy to coat many thousand in 5 minutes yup.
dry 15 min on top of the oven while the other batch cooks.... then in it goes.
EEEEEEEzeeeee

[texaswoodworker]

Sorry if this has already been asked, but how do you coat the bases of non hollow pointed bullets? Do they even need to be coated, or is the coating on the sides enough to prevent any leading issues?

I have a 9mm that will not shoot lead without leaving a lot of it in the barrel. I'm thinking of trying powder coating to stop that, and I cant decide between this method or one of the tumble methods.