10 Attachment(s)
Powder Coating 101 - Electrostatic Method
Electrostatic spray method only. No comparisons with other methods please. I know the reading is daunting on the main threads, so I wanted to give a little bit back of what I have learned from others and a very small portion of my own experimentation. I am sure improvements can be made. The following is the electrostatic method I have learned:
Equipment needed:
Safety equipment
Casting pot, mold, sizing equipment
Powder coating gun and compressor
Air nozzle
Powder
Acetone or other no residue solvent
Nitrile gloves
400f Oven (toaster oven or better)
Oven tray or jig
I begin with a Lee .356-125 hollow point mold by Erik at hollowpointmolds.com. I am using COWW adding 2% Tin solder, water dropped. These boolits are then sized to .356 using a Lee push through die using no lube. If lubrication becomes an issue, I use my standard case sizing lube, 8 parts 91% isopropyl alcohol to 2 parts Lee resizing lubricant.
Attachment 78456
After sizing, I put the boolits into sealed container with acetone.
Attachment 78457
I strain the boolits through sieve to remove the excess acetone. The excess acetone is then poured back into the sealed container for reuse. While in the strainer I blast the boolits with some compressed air to dry out the acetone.
Attachment 78458
I have designed a jig using machine screws, 2 washers, a lock washer, and a nut. These are set in the baking pan that came with my second hand toaster oven. If you are not using a hollow point design, you can sit the boolits base down on any non-flammable conductive surface that will fit your particular oven.
Attachment 78459
I then glove up and sit the boolits on top of the screws. it is easier than it sounds. I am doing 68 at a time, but this could easily be ramped up. The whole purpose of using the acetone is cleaning all oils from the boolit, so don't touch them with your fingers. Many people set them on flat trays covered in non stick Reynolds wrap.
Attachment 78460
Here is the finished tray.
Attachment 78461
I preheat these for about 5 minutes to get my boolits up to coating temperature and evaporate any lingering acetone.
Attachment 78462
Using my air nozzle, I clean off any dust from my spraying area.
Attachment 78463
I then transfer about one inch of powder into the reservoir of my Chicago Electric (Harbor Freight) powder coat gun.
Attachment 78464
There is a 4x4 sheet of plastic drop cloth over my coating area. I place the tray of hot boolits on a riser above the plastic to prevent melting and make for easy cleanup. The ground clip is then connected to bare metal on the boolit tray.
Attachment 78465
Continued in next post.....