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I know just enough to be dangerous about powder coating -- so you've been officially warned :-)
That said, I've been officially hooked on powder coating after I had my engine mount powder coated over 10 years ago. It has held up amazingly well despite screwdriver slips, clamp abuse, heat and so on.
As an aside, I know there are plenty of powder coating shops around most folks, however, I personally like to get my hands dirty and do it myself when possible. There is also something to be said for being in your workshop, hangar, or whatever and being able to finish up your parts that day without having to wait for the powder coating shop or make a special trip.
Here are some pics of my latest powder coating project -- the spring gear for a 601HDS.
I'll add more in the next couple of weeks assuming there is any interest. I'll also include some tips/tricks I've learned along the way ...
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Thanks so much for starting this topic! I had numerous small pieces powder coated on my STOL 750, but my local powder coat shop closed its doors recently and I decided it was high time I started doing it myself! In fact, I just received an Eastwood dual-voltage gun and I've got a large toaster oven ordered that I will use for small parts in my shop at my house. My brother is a builder and is going to get me a free oven from one of his remodels that I can use for larger parts - I'm going to install the oven in the hangar where I have more room and can easily add a 220v outlet.
I'm looking forward to any tips/tricks that you can share!
Here's a mod I made to my oven so it can handle larger pieces (or at least longer pieces). A good friend laughed and laughed when I sent it to him ... all I said was I converted my oven to handle larger/longer pieces. Without additional info, it is really funny in hindsight :-p
That said, I did more than just turn the oven 90 degrees. I moved the feet which required drilling new holes. If you look at the top, you can see I also drilled for a new cross member to hold the parts while they cure (?). The cross member was actually the rotisserie arm from the oven. I didn't get fancy, drilled some starter holes into the oven sides and then enlarged them with a Unibit -- fortunately nothing of concern in these areas. I then took the oven apart and cleaned out drill shavings and so on.
That's a great idea! I've got a very similar oven that I could easily modify the same way.
How critical are the temps to melt the powder and cure it? My oven is a convection oven, which is supposed to heat more evenly, but I put a small piece of aluminum on the rack and checked it with an infrared thermometer. The temps vary quite a bit, being highly dependent on rack position and proximity to one of the heating elements. In fact, even though the oven has a 450°F setting, it doesn't get nearly that hot unless close to an element. What's been your experience?
I haven't checked for temp variance on mine but I'm sure the temps vary as well. For the parts I've done, it hasn't been an issue. I've done up to 3 parts at the same time in my little oven -- each in different parts of the oven, with different lengths, and with different sizes -- so far haven't had any issues.
I have a convection mode as well and have always used it ... haven't tried without it for what it is worth ...
Each powder coat material will have temperature recommendation that should come with it. All the ones I've seen range from 375 to 425. I personally just set the oven to 425 and run with it. I tend to use texture type powder coats to avoid driving myself nuts trying to obtain a perfect finish. That said, if you are trying to do a gloss finish and the orange peel look isn't your thing, you might need better control for temps. That said, just going off what I heard one other person mention in passing. One can do a light sanding to remove the orange peel and putting a second powder coat on the piece to resolve the issue as well. I've haven't tried this yet though.
The pros will typically preheat their parts as well. I haven't found it necessary but when I do any powder coating at the TechShop, I put the parts in their huge oven while waiting for the oven to get up to proper temp (typically I used 400/410F for their large oven).
Good luck on your parts. Can't wait to see :-)
One more thing. I typically let my parts sit in the oven for a bit after baking at full temp for 20 minutes. This allows the part to cool down slowly and "rest". This may also have inadvertently helped with the uneven temp issue.
I'm working on my first project today. It's baking in the oven right now! I think you're right about the temps. I'm using Eastwood gloss black and it says to flow it out at 450. I set my oven to 450 but an infrared thermometer had it at about 360+. When I set the part in the oven, it started to flow out almost immediately! I've turned it down 50°F and letting it bake for 20 minutes.
I didn't clean the gun yet as I want to see if I need a second coat. However, I anticipate using the gloss black for several projects in the near future - is it OK to leave the gun "dirty" with the powder (and leave the powder canister attached) if youi're not changing colors? The gun will be stored in a relatively dry environment.
Part turned-out great!
I pulled the flap rocker switch and scuffed its concave face with #80 and then wet the convex face (bare, not powder coated - masked it with high temp fiberglass tape) of the adapter with G-Flex epoxy and scuffed the wet epoxy with #80 grit alum oxide paper (West's recommended method) and clamped the switch and adapter together.
The epoxy should be cured tomorrow. I think it will work - I have had great success with G-Flex bonding metal to plastic (that's what it was designed for!). In the event it pops off, the rocker should still work. Yes, I could have just installed a toggle switch and put the flap handle on iit, but this is definitely more fun! ;>)
This is amazing! And sadly has given my another side project idea -- UGH! :-p
Does this just snugly fit over a generic toggle/rocker switch? I'd love to see a complete picture of the part assembly and/or in action. Having a hard time visualizing the final result.
The gray flap-shaped handle (got mine on Ebay) has 2 set screws to secure it to a typical toggle flap switch. I have a rocker switch instead, so the convex curved underside of the new black part is epoxied to the matching concave face of the rocker switch. In essence, it converts the rocker to a toggle so I can use the gray handle. It would have been much easier to just swap out with a new toggle switch, but this gave me a chance to play with my new combo mill/lathe and my new powder coat gun!
I should have it installed tomorrow and will get a pic.
I don't have enough experience to say for sure. I've left my gun and so on "dirty" when working on extended projects and then clean when I know I'm done with that color or project. I haven't had a problem but live in Arizona and humidity typically isn't an issue.
That said, the manual on my gun definitely indicates you should clean after use and that it will be more difficult to clean later. I don't know what that means and hope not to find out :-) So far, it hasn't been an issue, but I also haven't left it for months without cleaning/using sort of thing.
As an aside, I also run a fairly large air/water filter from my compressor. If there is a chance you are running damp air from the compressor, I'd clean right away.
I do have a water trap on my compressor and a final filter on the powder gun. I went ahead and cleaned up the gun today - I was amazed at how easy it was - a few shots of high pressure air blew all the powder off the gun. I now see why powder coat is "addictive": the part can be used immediately as soon as it cools off and the clean up is quick and easy - no solvents necessary!