Intro: Simple Spray Booth for Around $70
I've been in need of a major upgrade to my painting "area", which, for the last four or five years, has literally been a few pieces of PVC pipes barely big enough to hold up one thing at a time. Always had to use it outside, since there isn't any ventilation in my garage. Now that I have a larger spray system as well as a proper airbrush, it's time to make something more worthy of it that I can use any time of year, even inside the garage during winter or rainy days.
This project is designed to use as few tools as possible, as little cost as possible (even if you don't have scraps and have to buy all the supplies). It was designed "on the fly", taking ideas from other booths online and incorporating the things I need in a proper spray booth, so unfortunately I didn't draw up any plans or blueprints you can use. I did my best to take down measurements and general things you'll need though, so if you want to make one just like this one you can, but the design is simple enough that it could easily be adapted to other shapes/sizes.
It took me a couple days to put this whole thing together, but I was being slow. It could easily be put together in an afternoon on your own, or in a couple hours if you have help. Let's get building!
Step 1: Measure Your Space
When making a spray booth, it's important to take into account the space it'll be taking up. In my case, I want to be able to stand in it without having to crouch, and I want to be able to move it outside or rest it just under the overhang of the garage roof so I can have airflow or enjoy a sunny day while I work. I also need it to be sturdy but light, and have a table space for smaller parts, airbrushing, or something I can just pull my stool up to and rest my legs if I'll be doing some long bouts of airbrushing. The table also needs to be able to support the fan, to keep me from breathing in too much paint fumes.
To give myself enough room, I went about 5 or 6 inches from the top of the garage door frame. This gave me 80 inches tall, which is plenty for me to stand up in. I roughly guestimated around 4 feet square for the footprint. Remember, these are *my* measurements, yours may have to be different and you'll need to adjust accordingly!
Step 2: Gather Your Materials
I opted for PVC again, since it's light, sturdy, and really cheap (all bonuses!). You could just as easily make this out of wood if you want something even more sturdy, but with the size I'm going for that can be really heavy. I also got 3/4" thick pipes and fittings, but you can just as easily go with 1" pipes for a bit more strength (and only a little bit more expensive).
My list of materials:
6 10 foot 3/4" PVC pipes - $9.90 (1.65 each)
8 3/4" L-connector - $3.84 (0.48 each)
8 3/4" T-connector - $3.68 (pack of 10)
1x4 foot 1" "common" board - $8.82
25x25" Filter - $4.47
10x25 foot clear plastic sheeting - $10.98
20" box fan - $15.88
3 outlet power strip - $0.97
1 roll of duct tape - $5.88
Total cost: $64.42 (plus tax)
Your cost may be different depending on the shop and whatever you may already have on hand, and definitely if you do a different size booth. I didn't have to buy the board, but it was the right size and meant I didn't have to cut anything down or glue up a bunch of scrap.
Step 3: The Outer Corners
You can start really at any point that you want, but I started with the outer corners just to get a feel on size and make sure things would beset to what I wanted. I started by attaching an L-connector to one side of a pipe, then measured 38 inches for the first cut mark. If I had measured 38" of pipe, this piece would have been longer than I wanted, since the pipe slides into the connector a little ways, and the rest of the connector adds some height as well. I went with 38" because it's a great average height for working: many workbenches are between 36 and 40 inches tall. Go with what feels comfortable though!
Once that was marked out, I secured the pipe into my new Workmate vise bench. Super handy! You don't need one - in fact, you can cut all these out by hand (or with a pipe cutter if you've got one). The Workmate just helped keep everything steady while I cut, which meant I could pay more attention to cutting straighter rather than focusing on holding it in place. Once that was cut, I grabbed another L-connector and put it on, then used the newly cut pipe - connector still attached - and used it to mark the length for the next one's cut. I'm not looking for 100% accuracy here, just enough to do what I need it to.
After those four were all done, I grabbed a T-connector, put it on the end of one, then attached it all to a long piece of pipe. My super cute helper assisted me here, holding one end of the tape measure while I measured out to 79 inches, one inch shy of the 80" goal to account for the top L-connector. Once this one was cut, I pulled it out of the T-connector so I wouldn't have to guess if it was all the way in, then used it to mark and cut the other three. Again, no exacts are needed, but each of these upper pipes ended up at about 39 5/8" long, give or take a 32nd.
Once all were cut out, I put on the top L-connector, then marked those with a "T" for "Top". Not really a have to, but it makes it easier to figure out which way they go at a quick glance, rather than trying to figure out which side is longer.
Step 4: Inner Platform
Now to start making those corner pieces into a gigantic box! The board I got, amazingly, was exactly 4 feet long - right at the size I want this whole thing to be. Of course, in order for it to have something to sit on, the middle beams would need to be cut into 2 sections. I also needed to take into account the width and depth of the T-connectors, which are 2 1/4" long in the middle and an inch deep inside (the furthest you can push in a pipe). The long direction came out to about 46 inches long, which I cut four of - three for later.
The short direction was a little more tricky, since even though the board was 11 inches wide, the back connector needed to sit a little further out than the front one to account for the corner piece. This gave me a small 9 3/4" pipe section, which I just cut at a rough 10" to give a little bit of wiggle room.
I cut two of those out, put a T-connector on each one, then attached them to a corner section. Once those were on, I grabbed one of the 46" long pipes and put the two together. Nice and easy!
Step 5: Finish the Box
Now that I had the cross beam together for the shelf, I put two more of the 46" long pipes into the bottom and attached one of the corners. This was a bit more finicky, and would have been easier with two people, but I held the two sides out and measured to as close to 48" wide as I could, to keep the whole thing as square as possible. Because I was alone I wasn't able to take a picture of it, but the opening gave me marks of about 47" and 13" on the tape measure. 47 - 13 = 34, which is the measurement I needed for the final two center pipes.
I also want a cross-bar to hang larger things from, so that means I needed to split the pipes in half for the top. Normally that would mean 46 / 2 = 23 inches, but remember how the T-connector has that section in the middle that the pipes don't fit down? These connectors are a bit over 3 inches long, which means a 1 inch gap in the middle to take into account. That means instead of a 46 inch pipe I needed a 45 inch pipe, and 45 / 2 = 22 1/2". I cut four of those out, threw those and a couple more T-connectors onto the fourth and last 46" long pipe, and installed them into the top in the opposite direction from the cross beams on the bottom.
It's not 100% sturdy, in fact it's kinda wobbly, but a few things will help fix that a bit in the next step. If you're a bit worried still, just cut some bits out and throw in a few more cross-beams with T-connectors. The table top plank also helps with stability, especially if you screw or bolt it down through the pipes. I secured mine down with duct tape 'cause it was there, though I'll most likely bolt it down in the future.
Step 6: Seal It All Up
Now comes the fun part: covering everything up in that plastic sheeting! These come in rolls that are folded up on themselves in weird ways - so be careful when cutting them.
To account for the top section, I had to add a couple feet to the top. 80 inches tall, plus 24 inches, puts it at 104 inches long for each side sheet, which I cut at 106" to give myself a bit of leeway. Starting with one side, I wrapped duct tape around the end of one sheet and a pipe, making sure the tape is on both sides. Then I worked my way down each side, pulling it flat as much as possible and making sure the tape was secure before moving on. On the front side I had a little extra, since cutting it in half meant nearly a full foot wider than the frame, so these I folded once over the pipe then taped down as best I could on the inside.
The second side was much the same, though since the pipe was already wrapped up by the first one I needed to overlap them and tape it over top. Then, as before, I taped each edge up around the pipes, going carefully and evenly as much as possible. It's very easy to start rushing here, so make sure to take it easy and take your time! The more open edges you end up with the more you will have to seal up later, so it's best to do this as good as possible the first time.
Step 7: Seal Up the Back
Now for the fan. There's tons of ways to do this, but to accommodate the opening I needed for the fan I rolled the plastic sheeting just past the width between the edge and where I wanted the fan to sit. Since the sheeting is 10 feet wide, that's more than enough to cover the back with enough spare to cut off and fill the area above and below it. Again, for this part I don't have specific measurements, since it was a quick eyeball to fill the open space.
The rest was a simple matter of rinse/repeat: tape up the top, work my way down, move to the next piece. For the overlapping sections, since this was the side that was going to get sprayed the most, I taped the cut edges together to seal it a bit better. I also did the same for the parts overlapping the fan, again to seal as much of it as possible so that everything goes through the filter.
Step 8: Secure the Fan and Filter, and DONE!
The only thing holding up the fan at this point is the tape and the plastic, so I taped down the feet to the table to hold it there until I can find a few screws to push up through the bottom. The filter is much bigger than the fan, so I wasn't able to get a full, proper seal on it, but it's tight enough with a couple strips of duct tape and will be pulled toward the fan when it is running.
Finally, I slipped the cord for the fan through the plastic sections in the back, and into the 3-plug power strip. There's enough room on it for the fan, my airless spray gun, and the small compressor/airbrush combo I have, and attaches to the outlet in the garage via extension cord. Super handy, small, and out of the way!
Some upgrades for the future will include a detachable hose that I can hook onto the back of the fan and slip under the garage door during the winter. I'm also going to more permanently secure the board to the pipes and definitely screw the fan down, though everything seems to be holding together just fine. Might even make a simple frame to slide the replacement filters in and out, but that's an idea for another time!
I hope this Instructable helps out if you are trying to make your own simple, basic spray booth. After working so long with such a tiny, old piece of junk, it's definitely an upgrade for me, and I can't wait to really start putting it through its paces!