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Old 02-08-2015, 09:50 AM   #18
88fordf150
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Re: Powder Coating - A Home How to

A few tips to add: 1) If powder coating cast steel or Aluminum be sure to out gas in the over first at 400degs for at least 30mins.. This opens the pores and burns off any oils left behind, if not done it will ruin your powder job. 2) Never use glass bead to sandblast aluminum that is to be powder coated. Glass bead will impregnate the aluminum and pop under your powder coat when heated making it look like pimples. I use aluminum oxide for blasting.

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Originally Posted by texasld View Post
Powder Coating - A Home How to

Let me start off by saying how much I HATE to paint. It's the bane of my existence. I'm not very good at it and it makes a mess. So I started looking at options for Powder Coating or PC, while I can't do anything big because of space constraints, I have started to refine the process of doing the small stuff in my garage and it works pretty well.

I hope this helps to inspire someone on the board to look into PCing small parts in there garage. The process is pretty cool and not crazy expensive if you want to make a small investment upfront. Of course You can farm this stuff out, but I figure I can save myself some coin and enjoy learning the process while at it.

What you need
I couple of things you will need are as following. Total cost is ~$400

First step in doing ANY sort of coating is prep, as we all know, good prep work makes good finish work.

1. Sand Blast Cabinet
I picked up mine at HF for $150 with a 25% off coupon (http://www.harborfreight.com/40-lb-c...net-68893.html) I use Garnet for blast media ($15 a 50lb bag) and had to pick up some odd plumbing pieces to change up the direction of the air inlet ($10). Many guys, myself included also add a new light to the cabinet. the supplied light is less than to be desired.
Note... You must have Dry Air and a lot of it to run one of these. I have a 80 gallon compressor and dryer/filter that does a pretty good job of running this guy. Also requires a dust system of some sort. A shop-vac works great!

2. Oven
DO NOT USE YOUR WIFES OVEN!!!!!!! WHEN YOU BAKE THE POWDER THE FUMES MAKE THE OVEN TOXIC FOR FOOD!!!! MUST USE A SEPARATE OVEN AND IT SHOULD BE IN THE GARAGE WITH THE DOOR OPEN
I got mine for a whopping $FREE.99. (Found someone who got new appliance, I took the old oven off of there hands. I have even seen people build their own. All we need is a temperature of 400 for 20 minutes. Let's say you have to pick one up off of CL for $100. (The burners make great heat sources for heating up seized small parts like door hinges.

Here is my setup. I built a stand for my cabinet because it's hard on my back to bend over. It's 5" to short for me to be comfortable, so I made it work for me!

Attachment 1341585

PC Gun

Once again HF comes to the rescue. Powder Coating Gun ($70)

http://www.harborfreight.com/10-30-p...tem-94244.html
Once again, must have DRY air. This system works Ok, uses more powder than desirable, but it's not to bad.

As far as powder goes, HF sells 3 or 4 colors, not enough. Although I have used the red and the black. The black they sell is flat, so for gloss black you have to get it from a few places that sell in small quantities. Eastwood sells powder and they have MANY choices. http://www.eastwood.com/paints/hotco...g/powders.html
or another company I know of is Powder by the Pound
https://www.powderbuythepound.com/ A lb. of powder goes pretty far when you are doing small stuff like this. Powder goes anywhere from $5.00 to $20. and beyond. So you want to get a few different colors let's say you spend about $40.


Process

Step 1 - Prep

This is where the blast cabinet comes in really well. Throw the parts in the cabinet and blast away. Make sure you get it REALLY CLEAN! All the rust and paint must be stripped or it will cause problems later.

Attachment 1341586

Took this guy apart because I was rebuilding them.

Attachment 1341587

Here is both sets of the hinges after blasting. This it what you are looking for. Once you get this far, slip on some latex gloves and wipe down your parts with acetone and a clean lint free rag. This helps get a really nice and clean part. Must get all the oils from your hands and the residual blasting dust off the parts before coating. If you need to mask any threads or toleranced holes, make sure you use tape that is rated for 400 degrees or higher. Like this (Gold Kapton Tape Polyimide High Temp 1/4" (6mm) x 36yds: High Temperature Tape: Amazon.com: Industrial & Scientific) You can also pick up some High Temp Silicone Plugs like this from eastwood


http://www.eastwood.com/high-temp-si...FywaAnfw8P8HAQ

Step 2 - Coat and bake

Tip... You can also preheat the part for about 20 minutes to help with powder transfer. You don't have to do this, but it helps.

I use two sawhorses space apart just so the oven rack sits on either side. This is not a great setup and it's not easy to coat. I'm working on building a rack that will work a bit better. I'll update those pictures later.

I forgot to take pictures of this step, but I get some when I get home later.

SAFETY NOTE Wear a mask as minimum. Powder is not good for the lungs.
Set your compressor to about 15-20psi and fill the powder cup with your color of choice.
Set the oven to 400 degrese and let it heat up while you coat your parts.
Hange your new cleaned parts with thin wire from the oven rack. *wire must be able to conduct electricity since this is an electrostatic process.* Connect the ground wire to the oven rack and spray away. Make sure you get everything coated evenly and fully covered.
Carefully move the coated parts to the oven and set your timer to 20 minuets (most powders cure time. Check the manufacturer's specs for slight changes.)

Attachment 1341588

Step 3 - Wait

Once the 20 minutes is up, pull the rack out of the oven. I use my welding gloves, I like them better than cooking mitts. Once the part is cool enough to touch, it is ready to be used or reassembled.
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