Diy-powder Coat/cerakote Curing Oven

I mentioned this in another thread and was asked to post my build here in the tool shed.

(shameless plug)
New proud member, will need your help with my 72 commando

I built this several years back, and the build thread I had for this oven was lost to the Photobucket debacle, so this will be a it will be a little light on written details and heavy on photos. I have about 40 pics that posted to the original thread, so I'll split them into posts of about 10 each.

I'll try to answer any questions you might have if I can remember...

I started with an old filing cabinet. Older is better in this case, as the shell was heavy guage and sturdy unlike most modern junky stuff you can buy.









I installed an inner box of hardibacker concrete board, they key here is not to have any metal attachments that can transfer heat from the inner box to the outer surface of the box.. After years of use I can tell you that this oven has ZERO heat loss from within the inner oven to the outside. if I had it to over again, I would have put the PID and wiring above the oven (in the top drawer) where it would be easier to access without bending over, but when I built it I was concerned about heat, so it all went below.









I had it in my head that I wanted to be able to watch what was going on in there. Had I to do it over again I would have built this much simpler without the windows and lights. Having said that, the Pyrex dishes and salvaged oven glass did not cost me too much and it makes for a super cool feature..





My pictures loaded in a weird order, so I'll end this post there and start a second post on this....

 

the insulation I used is the key to this oven, It's a rigid fiberglass insulation board rated to 550F. The manufacture says it can function well up to 600-700F for short periods of time. For powder coating or cerakoting, this is all you'd need. I do have some 1800F rigind insulation board that I use in building blacksmithing and metal casting furncases, but this stuff is probably better for this application as the foil liner makes for a nice clean oven without loose fibers floating around.

I had to find this stuff at a heating and cooling supply company, you'll probably not find it at Home Depot. it comes in a 4x8 sheet, and I'm pretty sure I was able to design this oven so that it just took one sheet, but maybe it was 2.

notice when I cut these pieces I left the foil liner longer, and was able to wrap them over the edges- this turned out to be awesome as the oven has stood up to years of use without any degradation or loss in the seal it creates. when I open the oven, there is not a spec of dust in there... FWIW- I used high temp silicone to seal the edges and wire hole. I also used some foil tape to help make a seal along the edges of the insulation. I've not had any issues with the foil tape, but it's not really exposed to the high temps of the inner chamber.



two layers on the door, stair stepped to help create the seal when closed. still fits perfect. I took extra effort to make sure my insulation attachment did not transfer heat through to the outer shell. In the case of the door, the inner layer is attached to the outer layer, which is attached to the hardibacker, which is attached to the metal door (all separately).






notice the holes for the wiring not line up- this eliminates the potential for heat loss there.


So I took the heating elements out of the toaster oven I bought at the thrift store, and custom made a housing for them out of sheet metal. Not exactly elegent but still works perfect without issue.

The wires are special high temp insulated wires, not sure where I found that, most likely E-bay like everything else in my life..












OK, I'll split the post again and do another.....

 

OK, so where are we at. I had purchased a surplus fan out of a vending cooler, mainly I wanted an air circ fan to keep my electronics cool. This never turned into an issue, but It's nice not to have to worry about any overheating issues.






I built out a box around my electronics..







Which by the way includes a temperature controller or PID- which I purchased off of E-bay, they have several models you can get cheap from some Asian country.. they come with a heat sink, and pretty good instructions..

PID controller | eBay














I have 3 different wiring diagrams in my photo file, I do not remember which one is the most current or correct- Electronics is not my strength, but I got through it with some help from others more knowledgeable. If you build one of these, you are on your own, this is for informational purposes only, I accept no liability for your use of any of this information!!!! Seek professional help when dealing with complex electrical devices. (I figured it out and so can you)..


(edit: the first one is all wrong, I'm pretty sure the 3rd version is the most accurate, but again, never wire something with a diagram some moron posted on the internet)










This oven has a cord that I can wrap up in the bottom drawer but pulls out a port in the back when It's time to plug it in. A nice feature when it's not in use....







Some guards over the heating elements, please make sure you do this...


just realized this is an early picture, notice above I added the aluminum tubing and riveted the mesh to it, much sturdier and less redneck..


the money shot..



FYI- the PID works great. It shoots up to temp very quickly, the insulation is better than that found in a normal house oven. it usually over shoots by about 1 degree F and then never deviates more than 1 degree F after that. These PID controllers come with a variety of programmability, but I bought one of the simplest ones. These can be used for glass annealing ovens for example where you can program a ramping temperature drop over several hours, and then go to bed and let the oven ramp down the temp for you. For this oven, I just set it to my desired temp, not even sure how to program it for anything more complex.








I'm sure I left plenty out, I'm willing to answer questions if I can remember any of the answers..

Oven still works great, it's been near a decade since I built this...

 

Let see some parts that were “cooked” in there.

 

I don’t have any currently except for a couple of prototype folding gunstocks that I’m working to patent, and I’ve managed to avoid putting any pics of those on the internet.


I’ve got some pics somewhere of older projects i’ll try to find.

 

Thanks for the write-up. I have several sets of headers I'd like to ceramic coat, and coating companies want $250-$350 or more to coat them. I think your file cabinet is too small for my applications, but it does give me lots of ideas if I want to get ambitious.
I have an old Paragon kiln I picked up that uses cones for temperature control. I may "borrow" some of your ideas to retrofit a digital temperature control to make it more usable for other things.
Thanks-Donny

 

Yes, many folks are using these PID controllers to upgrade older kilns to have modern programmability (at a fraction of the price of a production ramping kiln). There are some good threads on doing that. I have a couple of kilns, but my filing cabinet oven actually has more hanging space than either of them.

I’ve seen threads where people have effectively built a full size walk-in powder coat oven using the same methods I did.

For doing headers, I’d look into using the shell of an old upright deep freezer or maybe even a large chest freezer. The local power company here recycles these for folks, I bet they’d give you the metal box and you wouldn’t even have to do the stripping. Heck, they might even give you the fiberglass or rock wool insulation you’d need, but I’d still concider the foil lined insulation i used as it makes for a nice clean interior without all the fiber dust, and you’d know it could handle powder coating temps.

 

I cannot find any pics of any of the guns I've cooked in this thing other than my proprietary work I'm doing that I can't share on the internet.

I did find these from a recent project I built for my 4x4 camper van. I call it La Tortuga and figured she should have an appropriate hood ornament. Built this using SuperSculpy polymer clay, cool stuff. shape, then bake it.











I'll soon be Cerakoting another divergent project that I'll post some pics of here.

 

Ha, nicely done. I have to say when I first saw the sculpture, I didn’t anticipate where it would end up.

 

I told you I'd get around to posting some pics at some point....

 

Very cool.. Or Hot..