DIY Refinishing oven

[Netpackrat]

So, AlaskaTRX and I have a bunch of firearms that need to be refinished. I know how I want them done; KG Gunkote over either park or K-phos. My brother had the AK I built for him finished in this manner and it turned out beautifully; unfortunately for us, the gentleman who did the work passed away a couple years ago, and I haven't really found anybody else doing the same work for anywhere near the price he was charging. Certainly there is nobody in Alaska working with Gunkote, that I've been able to find. I gave serious consideration to sending them out to somebody like Chris (once he's set up for refinishing) to do, which would make some sense for one or two rifles. But, I've got something on the order of 5-6 that could use it, not counting my brother's stuff. So, when you consider what a quality refinishing job is going for, plus the cost of shipping out of state, that's not really realistic either.

Up to now, the obstacles to doing it myself have been the hazmat shipping to AK, and having an oven big/long enough to cure a barreled action. The former kitchen oven I am using for powder coating just isn't big enough. Looked at various DIY powder coating ovens, and they're a possibility... But the builds I've seen look like a project unto themselves, and I've already got plenty of those on my plate.

Was googling DIY ovens again last night, and I came upon this:

http://www.snipershide.com/forum/ubbthr ... er=1861428

Now that looks like the Easy Button for paint curing ovens. Even buying the cabinet and all the needed materials new, and paying for hazmat shipping on the Gunkote and Kphos, I don't see any way that I could not possibly save a lot of money doing my own refinishing (I've already got the compressor and blast cabinet situation handled), even if I screw up the first couple and have to re-do them. What I want to know, is if there are any fatal flaws to how this guy built his oven? And how much hassle would it be to set up some sort of thermostatic control? I don't care whether or not it will reach the 400 degrees I need to powder coat; I'm just trying to reach the 325 that Gunkote requires.

[Aglifter]

Skip the BBQ thermometers and get some NSF ones - still not too much. A fan will do a world of good on keeping the temp stable - I am extrapolating from commercial ovens. How important is temp to you? You should be able to set up a thermocouple and a PLR pretty easily, but that can either be dOne decently, and cheap, or precisely, and ridiculous.

[Aglifter]

Automation Direct, or Grainger, is where we usually get those kinds of parts

[mousegun]

How do you want to set up your controller? Start by reading HERE and then decide. Type K thermocouples are easy enough to come by. Pertty much most of the ovens and environmental chambers at work use this brand of controller; they are more or less an industrial standard. Even if you go with cheap chinese, there is a lot of info on that page and its links for you to digest.

[blackeagle603]

DIY PID for casting pot should be up to the oven task. Start reading at this Cast Boolits thread.

[Precision]

I built one recently.

I saw that article and just couldn't part with that much coin on what I figured would be a once a year project at most. Working on my second gun in a month.

I took a steel mailbox for the base. Screwed that into a piece of 3/4 plywood to keep it tip stable.
Then bolted a gas water heater venting tube flared couple(6" diameter) over a 6" hole I cut in the side of the mailbox. Then 44'' of 6" diameter heater venting pipe.

The mailbox has the cut down remains of a twin element toaster oven mounted to a pan so I can slide it in and out if needed. The mailbox and the column are insulated with a double wrap of R-19 pink fiberglass. The tray from the toaster oven has 3 mounting brackets on on it and a section of 2/4 screwed to the outside for an insulated handle.

I am actually cooking off the son's shotgun bits now.
Used it for dad's old .22 before Christmas. Worked great.

Might load up some pictures of my ugly but effective contraption tomorrow.

[HTRN]

Most of the homebuilt ovens I've seen pictures of, use cheap electric oven elements, a solid state relay, and a PID. The larger ovens often add a high temperature fan to circulate the air and prevent hotspots. Caswell Plating has some guys showing off their homemade powder coating ovens.

Ultimately, the limitation is how much power is available, and how much you want to spend. My advice? build it bigger than you think you should. I can almost guarantee you'll have a job going "Dammit, I knew I should have built it bigger!" in short order..

[Netpackrat]

Phase 1 complete; oven housing acquired thanks to the fine folks at Craigslist. It was frustrating paying $80 for basically the same thing as I gave away for free 15 years ago (finished college, and didn't have room for it in my truck), but that beats the $230 that they are asking for them these days.

Next, to locate some "rigid duct board" insulation. Lowe's didn't have any, but maybe the local building supply place will.

[blackeagle603]

"rigid duct board" insulation

HVAC Sheetmetal fab shop/supply

[FastRope71]

Which coatings are you looking at using? I used 2403CR (Dark Gunmetal Gray) and 2414S (Satin Royal Blue) to coat a Ruger MKII. I did the bolt half 2403CR and half 1600F (flat, high teflon black) So that the bolt shows black when closed.

I use a pasche VLS air brush on a horror freight compressor.

Make sure you have some MEK Handy for clean up and clean out your brush every time you set it down for more than a few minutes. When you are done for the day, blow a full cup of clean MEK through it and remove and wipe down the needle.