Powder Coating Oven Update

Greetings Gents.
Just an update, the powder coating oven works!
here's some pictures of the oven:
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In true RCM fashion, I started with what was free / handy, and worked
up from there. The interior walls of the oven are fabricated from
scrap heavy duty galvanized roofing panels (free from a welding
friend, left over from one of his projects.
After many sleepless nights on how to turn these corrugated panels
into a box, I finally stumbled onto the idea of wrapping the edges
with 1 5/8" galvanized channel from Home Despot (normally used for
metal stud framing work).
Once the panels were edged, I pop riveted them into the ~3'x3'x6' tall
rectangular box, and added some angle iron hinges and feet. Now the
problem was how to insulate the dang thing.
I searched for some of the rigid fiberglass duct board, but promptly
turned that idea down as "Holy Mother Of Pearl!" is that stuff
expensive ($45 a 4x10 sheet, the best price I could find locally, and
it was only 3/4" thick, couldn't find any 2" stuff locally)
After much head scratching, I picked up some cheap R14 wall
insulation, peeled off the paper liner, tacked it to the chamber walls
with spray contact cement (Not much contact cement, just enough to
temporarily hold the stuff in place).
Once the insulation was in place, I wrapped the whole stinking thing
with Al roofing flashing held in place with Al duct tape (the most
expensive part of the whole project). At 400F internal temperature,
the outside skin is just above room temp :)
Three salvaged oven heating elements provide 6KW of heat, resulting in
a 20 min run at full power to get up to working temp (400f), then the
elements run at about a 40% duty cycle to keep the oven at temp.
Here's some pictures of the first test samples I coated:
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The 'Peace Sign" is coated in Candy translucent purple, but the camera
flash makes it look blue.
One pole is coated in "Black Chrome" (which is way cool!)
The second pole has a base coat of black chrome followed by a second
coat of candy purple (which turned out WAY FREAKING COOL!)
Considering I had no clue, I'm pretty impressed with the results! I'm
using a horrible freight powder coat gun, and powders from here:
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(no affiliation, other than a happy
customer)
So tonight, I lift my cup to Gary Brady and all you fine folks here on
RCM for the excellent advice and inspirations!
Take Care,
James Lerch
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(My telescope construction, Testing, and Coating site)
Press on: nothing in the world can take the place of perseverance.
Talent will not; nothing is more common than unsuccessful men with talent.
Genius will not; unrewarded genius is almost a proverb.
Education will not; the world is full of educated derelicts.
Persistence and determination alone are omnipotent.
Calvin Coolidge
Reply to
James Lerch
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Pretty cool, James! When I get my new shop set up, I think I'll give powder coating a try. Has anyone here built an oven out of an old upright food freezer, and if so, how did it perform? We have an old refrigerator converted into an oven at work that we use to keep magnorite powder dry. It seems to make a pretty good bake-out oven. The door gasket may have been changed out to a more suitable heat resistant material. I'll check it out to see.
RJ
Reply to
Backlash
Beautiful photos James!
Ya had to go and do it. Ya had to show me yet another thing that I could do myself [one of my favorite quotes is "Why should I pay someone $40 an hour to screw up what I can screw up myself for free?!!"]
So I'm already looking at Columbia Coatings and they're not terribly far from me. Hmmm... maybe I could run down there and see what they've got surplus...
Thanks! -- terry
Reply to
prfesser
Well done! I have been reading about this process from time to time and wondering how difficult it would be to build my own oven. I wonder how large an oven could be built as I was thinking of doing a tubular steel fuselage. The length is 16' x 5' tail height and 30" width. I was thinking of a one-off box with reflective material inside. 400 degrees is below the combustion temp of wood and with reflective material inside. Maybe a small fan for circulation of air along the lines of a convection oven. Thanks for getting me thinking about this again.
Reply to
Ebby
Hi James, I love your paint job, its a pity about the welding. Regards. Rotty
Reply to
Rotty
Sounds like a linear oven - continuous moving 'work' ramp up hot ramp down...
Wonder how long one has to have the 400 degrees for a good flow - ??
Martin
Reply to
Martin H. Eastburn
I looked into that approach, but was concerened about the styrofoam insulation used on the internal walls..
Anyone know at what tempature styrofoam turns into 'mush, smoke, flames'?
Take Care, James Lerch
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(My telescope construction, Testing, and Coating site)
Press on: nothing in the world can take the place of perseverance. Talent will not; nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination alone are omnipotent. Calvin Coolidge
Reply to
James Lerch
Well, I read of one company that was / is converting old cargo containers into powder coat ovens... No idea how much power it would take to properly heat the thing in a reasonable amount of time, but...
Carefull, once you have a powder coating oven, EVERYTHING looks like a potential powder coat project :)
(for instance, as I spoke with my wife "Honey, these door knobs are looking a little ugly, you want them chromed, gold, metal flaked, or some other color :)
Take Care, James Lerch
formatting link
(My telescope construction, Testing, and Coating site)
Press on: nothing in the world can take the place of perseverance. Talent will not; nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination alone are omnipotent. Calvin Coolidge
Reply to
James Lerch
I knew someone would mention my ugle Al welds :) While they aint pretty, they sure seem strong ( The 'peace sign' supported by the corners will support my weight!)
I've recently switch from 3/32 filler rod, to 1/16 filler rod, and seem to be able to get a little nicer looking beads, but heck I'm just happy I can make two pieces of Al into one!
Take Care, James Lerch
formatting link
(My telescope construction, Testing, and Coating site)
Press on: nothing in the world can take the place of perseverance. Talent will not; nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination alone are omnipotent. Calvin Coolidge
Reply to
James Lerch
I wouldn't take it much above 200-300°F. You can cut the stuff with a soldering tool quite easily.
A typical hotwire foam cutter will run about 500-800°F, FWIW.
Tim
-- "I've got more trophies than Wayne Gretsky and the Pope combined!" - Homer Simpson Website @
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Reply to
Tim Williams
Cargo Container - now power coat car and truck fenders and hoods or the whole car! Martin
Reply to
Martin H. Eastburn
Hi; I have been interested in powdercoating,but the oven was always a problem.Thanks for sharing your oven design.I have been googling powdercoat ovens and here is a link to another homemade oven.
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realize that you already have a oven,but there are many lurkers(myself included) that are looking for as many ideas as possible. Bead_runner
Reply to
bead_runner
What kind of insulation would you all recommend?
I keep running the idea around in my head and think 400°F... fiberglass... which can handle 1000°F... so let's heat treat aluminum... and hell, add on another 200 degrees and we can anneal glass too... but that melts the fiberglass. And I don't want to waste 2300°F kaowool on something only reaching 1600°F (if I'm going to use that stuff, I might as well heat treat steel too...).
Ack. It's a vicious cycle. :^)
Tim
-- "I've got more trophies than Wayne Gretsky and the Pope combined!" - Homer Simpson Website @
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Reply to
Tim Williams

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