WARNING: If the thought of listening to some random dude you've never met going on for hours and hours about sheet metal, oven elements and PIDs makes you queezy, then I suggest you brace yourself. Now on the other hand, if you DO enjoy hearing about steel studs, rock wool insulation and thermocouples, then go mix yourself a gin and tonic, or simply pour yourself a glass of water and venture in to my world of building your own powder coating oven.
Why did I do this to myself?
In the process of rebuilding my 1999 Suzuki DR350 I had a revelation. When it was time to fix all of the rusted metal on my DR350, including the frame, I would try my luck at a process called powder coating. This article is how I went about it.
First off, let me warn you now that this is by no means a tutorial, how-to, or any other kind of guide meant to be duplicated or copied. This is the first time that I have done this and honestly I'm simply not the type of guy you want to follow during a zombie apocalypse. Buuuuttt...if you are keen enough, you should be able to get it all figured out, and you might actually be able to do it without passing away. But seriously, don't get pissed at me when you realize that I didn't mention dimensions, or any other "important details". I just create this junk as I go.
So what the heck is powder coating?
Powder coating is a pretty slick process that leaves a durable and long lasting (if done properly) finish on metal. I won't bore you with all of the science behind it now, but here are a few general differences between paint and powder coating. Unlike paint, powder coating is, well... powder, not liquid. It's normally some form or another of plastic or polymer that is electro-statically charged by a special powder coating spray gun.
The (generally) metal piece that you're coating is grounded, which makes the electro-statically charged powder attract itself to the object the way static also tends to secretly cling a freshly dried sock inside of your pant leg when you aren't paying attention. Once you spray the powder onto the object, the powder must be cured, or baked, to actually activate the real beauty. The process of curing is quite simple. The part must be baked at about 400 degrees Fahrenheit for about 10 minutes give or take in order to "melt" the powder onto the part.
So, we now know the fundamentals of powder coating and can finally continue with the article without being confused. But for those who skipped all of the above text, here is one last chance to get a very basic understanding of the process of powder coating...
1) The powder is electrostatically charged and adheres to the grounded part.
2) To cure the powder, you require something to bake the part in. Generally an oven.
Step 2, my friends, is what this article is about. I invite you all to join me on this journey of sorrow, despair, triumph and prosperity. Lets begin!
Day 1: Building the frame
So, the idea here is to build the entire oven, including the frame out of metal, instead of wood or any similar materials that would cause my house to burn down while I wasn't looking. That does neither me, or my house, any good. Seems easy enough...right?
The solution for a nonflammable frame is a simple one. I will use steel studs that can be purchased from my local big box store. The studs are fairly priced and can be purchased (at my location) in 8' and 10' lengths. I bought enough linear feet for my frame, and you should do the same, or not!
Shown above, for anyone who needs to read it just to be certain, are some of the steel studs that I picked up from my local ©The Home Depot. Actually, my local store didn't carry these for some reason so I had to drive to the next nearest store. Luckily there are almost as many ©The Home Depots than there are ©Starbucks so the next nearest store was only 15 minutes away from the nearest... Anyhow.
These metal studs come pieced together as 2 and you have to pry them apart in order to use them for this specific project. I'm not really sure if they are designed to stay together, and the more I think about it, they probably are, but that didn't matter, because for this project, they need to be pulled apart! Oh, and no, I didn't take any photos of this process, nor am I going to write about separating them, but I will say that if you can't figure it out, please stop now because it only gets worse.
Warning: these studs are sharp, so don't scuff your stuff.
Things needed to make this happen.
These are the things I used - without photos - because if you don't know what a measuring tape looks like, my heart goes out to you.
- Measuring tape for measuring things
- Speed Square for squarely marking and scoring things
- A pair of sheers made in China for cutting metal things
- A few Vise-Grip® or knockoff brand C clamping pliers for clamping things
- Sharpie® marker or similar for marking lines on things
- Utility blade for scoring the stud things
- A drill for drilling things
- A riveter for riveting things (I highly suggest an air riveter simply because the hand ratcheting kind will gets old after about the 1,250th rivet thing)
- A LOT of rivets to go with the riveter thing (I'm starting with 500 of these things)
- The proper drill bit to match the diameter of the rivet things
- Some beerskis' to ease things
- I've probably missed some things
Lets plan this out, shall we?
Planning this build wasn't so tough with the help of this newfangled internet phenomenon. I have been able to search around and find photos and other information on what I am trying to accomplish and things like that help guys like me do stuff like this.
So, after some internet research, I decided to take a route that I didn't really see used which is the overall method of assembly. It may or may not be more difficult, but I must say, it worked well for me. That said, I now know that my overall goal is this:
The general idea:
Assemble the oven in panels. One "panel" at a time, 3 walls, 1 door, 1 floor and 1 ceiling for a grand total of, you guessed it, 6 panels. Rivet the panels together. Finish.
A little more detailed:
- Each panel will consist of its frame, obviously, which will be cut and riveted together to create what is very similar to a wall in a house.
- All wall panels will have either the outside, or the inside sheeting riveted on. One or the other, but not both at once. We will need access.
- Both the floor and ceiling will have the outside sheeting riveted on, be filled with insulation, then closed up with the inside sheeting to create two complete panels, ready for action.
- The floor will be laid on the ground, proper side facing up while each wall will be sat on top of it. Notice I said wall and not door. The door isn't involved just yet.
- Drink more beers
- Once all three walls are now standing up, on top the floor, in their proper operation position, we put the ceiling on. Note to self, be safe, these make for heavy dominoes.
- Square it all up. Slide shit around until it looks good enough for government work.
- Each wall will be riveted to the ground, ceiling and adjacent walls. This is why we left the walls unfinished. Now we should have a solid structure.
- Insulate each wall.
- Rivet the outside panels on to cover it all up
- Figure out the rest later.
So now I have a general plan, which is always good when tackling something like this. Oh and don't worry if you think you missed something. I haven't mentioned anything yet about sheet metal yet, or a few other things, mainly because I haven't gotten to those part yet. But don't worry, I promise if you decipher this entire article, every detail will be here...somewhere.
Lets get this thing rolling, one panel at a time...
So, we know we are going to slay this beast by making one panel at a time. So what you - and I - need to decide is what the overall size of the oven will be. My decision was fairly limited due to the (affordable) sheet metal near me. This stuff generally comes in 4x8 or 4x10 or some shit like that, but don't quote me, I'm not an expert on sheet metal. Anyhow, you can get other sizes I'm sure if you want, so figure it out, because it will be the most factoring step on what you can or can't do/afford.
I knew that my oven was going to have an exterior dimension of 4'x4'x6' which means that I would approach it like so:
Floor and ceiling would be a no brainer at 4'x4' for both.
The three walls would be as follows:
Rear Wall: 48" wide by 65" high
Side Walls: 41" wide by 65" high
Door: 4' wide by 6' high (more on the door later)
If my calculations are correct, and I'm not too drunk, that should end up with an external dimension of 4wx4dx6h. If not, let me know and I will edit it, or tell you to screw off, depending on how you approach me.
So, The first step necessarily necessary is going to be me, figuring out how to build the frame. Lets get back to these wonderful steel studs we talked about earlier, shall we?
Cutting the studs to size
Super Pro Tip #139: How to cut steel studs
I found that the easiest way to cut steel studs was with a utility blade and a speed square. Simply snip the sides of the stud, measure across the top, hold a speed square on your measurement and use the utility blade to score a line across the stud. Now all you have to do is fold the stud over and it will break on your scored line. Do you have to use this method? No. Did it work for me? Yes. Either way, you need to cut these babies down to whatever size your panels are going to be!
Here's a wonderful photo of some of my studs cut down to size.
Assemble the frame!
Once your studs are cut to the proper lengths (you did this, right?) we can start to assemble the frame for our panels. This isn't as hard as you might think, in fact, its quite simple and extremely fun, minus the fun part.
So what needs to be done to make the frame is simple. We need to connect the studs to each other and rivet them together. Easy enough, right? Wrong.
The studs I purchased are designed in a way that prevents the studs from sliding inside of each other without some modifications. Easy enough though because the "modification" is simply snipping the folded edge and bending it straight. I didn't take photos of the actual process and I'm having a hell of a time explaining it, so maybe just look at the photo below to get an idea of what it is I am talking about, k?
As you can see, the lip is snipped, and folded flat which allows the stud to slide right in. Once it slides in, clamp that baby down with a C clamp, a D clamp, or an E clamp, but DO NOT USE an F clamp or it will cause major issues down the road. You have been warned.
Once we have the clamp clamped, we can drill a hole with the proper drill bit that matches the rivets you bought and then we can rivet!
Riveting is fun at first, but rest assured it loses its luster after about 1000 rivets.
REAL (WO)MAN ALERT: If you attempt to take on this project with a hand riveter, you are here by considered by myself, a world class human being. I salute you.
Ok, so I have one corner riveted with one single rivet. Why one? You don't want more than one because you won't have a pivot anymore which means you wont be able to get your frame squared. Leave one in each corner until you have all four corners riveted, then you can square it up using your sheet metal and then rivet the rest! (four total in each corner and any center beams and don't forget the other side!)
Once you have all of your rivets in, its now time to skin one side. I didn't take photos, but it doesn't require them. Simply lay the sheet metal on top of the frame, drill holes and start riveting. How many rivets? The more the better. Every 3 or 4 inches isn't a horrible idea but feel free to do what you want.
Insulation. Why must it itch so badly?
Squared up with our center beam in place and one panel on, this baby is ready for insulation!
This step is straight forward and goes like this:
- Measure where you are putting insulation.
- Measure the insulation.
- Cut the insulation.
- Slide the insulation in.
- Itch for the rest of the day.
Button up the first panel
Once your panel is nice and insulated, it's ready for the final layer of skin. How exciting!
Do what you did earlier and lay the sheet metal on top, drill and rivet, drill and rivet, drill and rivet, etc etc etc etc etc...
Once complete, you should have something that resembles the following. If not, you did something wrong and I can't help you. No one can.
Rinse and Repeat
Finally! We have a panel done! Guess what? After you do panel one, you get to go all the way back to the beginning and start over. Guess what? After that, you get to start over again! Guess what? Again. What? Yep, again. Eventually you will have a floor, a ceiling, and three walls for a total of 5 panels.
BUT WAIT! (You are reading the directions first, right?)
There is one difference from the floor to the other panels, and it is VERY important. DO NOT SKIN BOTH SIDES OF THE WALLS!
If you skin both sides of the walls, you won't be able to rivet this crap together and you will end up having to tape it together or something ridiculous like that. So just trust me on this and only skin one side! Here's a photo just in case you aren't understanding me!
You can however, completely fabricate the ceiling panel the same way you did the floor.
Get a pal or something or just get swole and lift these panels up and butt them together where they need to be. Once they are butted up, you can start riveting everything together. Down into the floor, and across into the neighboring panels.
Eventually you will have something that looks similar, but probably better, than the photo below.
Here is a test fit for fun. Suzuki DR350 Dual Sport frame. The whole reason behind this crazy ass project.
One more wall up.
Get some help, because the fabricated ceiling is heavy, and needs to go on the top... I didn't have help, but then again, I am comparable to superman as far as strength goes.
Now we can start to insulate the walls. Follow the same directions as the floor and ceiling and you should be A-O-K.
Finish the walls
Once the walls are nice and insulated, it's time to skin them. The way the oven is designed, the skin runs the total length of the outside walls and will grip both the floor, and the ceiling panels making a nice solid oven when finished.
Shes a beauty. Now all we need is a door!
Chapter 53: The door.
Ok, so since this thing feels like it's made out of recycled tuna cans I knew for sure I would have to stiffen up the door "hinge" area or else the weight of the door would rip this thing to shreds.
I went out and purchased the angle iron you see below, the kind with the holes in it. Also, i grabbed some self tapping screws (and washers) and the biggest rivets they had at home depot. I forget the size, sorry. Do you still love me?
The piece ran the length of my oven perfectly without cutting it, so I put it on the corner, and used the self tapping screws (with washers) to secure it to the panel. Choose whatever side you want your door to open towards.
I bought regular door hinges and mounted them using the beefy rivets that I mentioned earlier. This allows them to close without bottoming out like it would if you used a self tapping screw.
Assembly begins on the door.
The entire door was based around one important item. The window. You don't need one, but not having one is pretty much a horrible idea. So its up to you.
I removed a "window" from a dilapidated convection oven. Much easier than trying to make a window yourself because you run into expansion/contraction issues with the glass and the glass frame. Trust me, find a junker and use the window from it. You will thank me in the end when you don't have to remove glass shards from your eye sockets.
Basically, use your imagination for the rest. By this stage, you should be a metal stud fabrication guru and have absolutely no problems trying to figure this part out.
Below is some mock ups, and final assembly of my door. Enjoy it!
Assembled oven. Finally?
Here is a shot of the oven assembled. Its a beast, isn't it? There aren't any controls yet, or heating elements, but that part comes next, so stay tuned!