How to Build a Air Compressor on a Budget

This air compressor gives me more air than most storebought units, and I built it for half the cost. With the high demand of needing air tools for my Jeep projects, my J20, my Wrangler one ton swap, I needed something that could keep up with me. So, here's exactly how I built this compressor if you guys want to know. So, I started with a tank for 40 bucks off of Facebook Marketplace. Honestly, it was a pretty good tank. I didn't look inside of it. I was taking a gamble on it by not looking inside of it. So, if you guys can make sure you look inside of it, make sure it's not rusted out. Um, from there on, after I bought the tank, I popped open the bongs or the bushings on both sides. So, the bushing, there's a bushing here and there's a bushing on the bottom. I went through and I pressure washed everything in the tank, ran water through it, swirled it around, got all the dirt and debris out of there, and it was actually really clean, so I didn't have to worry about it. I I lucked out on that one. A lot of you guys, I know, will probably buy them, and they'll be rusty or whatever. So, just make sure that you can verify that these aren't rusty, cuz if they're rusty, then you just wasted 40 bucks. So, anyways, so then I went to Harbor Freight and they had a pump in stock. It was between the three horse and the five horse. I ended up going with the 5 horse V twin two-stage compressor. Couple reason I wanted this one. I wanted to build something big. I could just go to Tractor Supply and buy a compressor, a whole setup for, you know, 7 800 bucks, but it's only going to put out 8 9 10 CFM. I wanted something high. So, this one does 15 CFM, two- stage, which is super important. And the best part, there's only 240 bucks. So, after I got the compressor pump, I figured, "Oh jeez, how am I going to power this?" Well, the old motor that came on the compressor didn't work for me. Um, the shaft was keyed all wrong and everything. So, I ended up picking up this EMZ compressor. It's a 5 horse compressor, singlephase, 230 volts, super nice compressor, continuous duty, non-reversible, thermal protective. Shaft is 7/8, which in this kind of application, you want 7/8 over something like 5/8. You know, you want something a little bit bigger to pull. So, anyways, I got ordered this one. This was about 280 bucks. So, I had this and this. Then [snorts] here came the fab part of it. So I busted out my CAD cardboard aided design and I fabbed all this up. Cut the cardboard out to what I wanted. Cut my template. Ran my beads on here. Ran the beads on there. And uh I'll drop some footage of that right here. So that's the fab part of it. As you can see on this side, just have a V-groove type A belt. Make sure that our pulleys are lined up. Our pulley, this one was a 5 and 1/2 in pulley. picked this up uh for 30 bucks on Amazon, 20 bucks on Amazon. 7/8 shaft keyed, 5 and 12 inch pulley. This is a 16 16 1/2 in pulley. If you do the math, it'll tell you what RPMs you need to run this sufficiently at 15 CFM. Um after you do that, it's just a matter of doing the calculations to buy the right belt. Once you buy the right belt, put that sucker on there and pull it tight within a/ inch deflection. So, you want a/2 inch deflection in your belt. So, go around to this side. Let's talk a little bit more about our about our plumbing. So, it comes with the 3/4 fitting. It also comes with a 1/2 inch fitting. Now, a lot of guys online were like, I can't figure out what fitting this is. And maybe I didn't, but when I went to the part store, I found that this is just your regular MPT, you know, your national pipe thread. So, that made it super easy. This line's super tight. And I was going to do a black iron out of here and down, but I ended up just finding a hose on Amazon for 40 bucks, and that ended up working out perfect. Has 3/4 MPT on this side, screws right into here, tefloned everything, and then I ran it all the way down. This goes right into our bung here. And this bung, let me tell you guys, was a pain to get out of here. All right. Um, basically this is a 2 in to 3/4 inch bung with a 3/4 in MPT check valve for a tank to a 3/4 in 90 to your 3/4 in uh male to male fitting to go into your 3/4 in compressor hose. And I'll put a link for this in the online as long same with our same with our check valve here. So off of the check valve, there's this little quarter inch line here. I know my dark. This tells your pressure switch when to shut off. So it runs through here and clicks that. So when the compressor is running and it goes, that basically triggered this triggered this switch to shut off. And that's about it. So that's our intake side of it. You could do all this out of black iron. You could black iron 90 3/4 down into there. But this hose was 40 bucks. Easy day. Not too worried about it. So from our compressor motor, our electric motor here, which is an EMZ, we'll see how it runs. I've heard good and I've heard bad. But I wanted to keep this compressor low budget. So, I didn't want to I didn't want to keep it, you know, get a $1,000 motor. So, I ran 10 gauge S cable, the same stuff I used for my uh my panel install video, the last video I did, just ran this to here and ran it into here. And I'll drop a clip of that. I think I have a short of that actually. If you go check out my shorts, there's a short of how I ran this. It's super easy. I'll pop this cover off right now. So, here's a look into our electrical. So, all it is is just line one, line two, and ground coming off our 10 gauge. That follows to here. And then you have your line one and line two. Grounds wired together. And then off of there, you have your ground. Line one and line two. This says motor. This says switch. Super easy. coming out of here running this way and it goes into our 30 amp plug on the wall. That's the electrical side of the house. So, we have pump motor, we covered our drain, all 3/4 in. This is a little add-on here that you don't have to do, but I did. This is 8 in brass. I think I did a 4 in with a cap. And this is solely just for draining the oil. There's a plug in here. And if I guess I could have notched this or something and ran it better, but I don't know. For 10 bucks, I just bought this little stubby part here. Teflon it all together. Now I can pop this cap off and drain my oil out here. So, moving on. Talk about our regulator. So, this is just 3/8 6 in pipe galvanized. Bought this for five bucks. Then I went to Harbor Freight for their 20% off sale. And I picked up a regulator and lubricator. So this is going to regulate to our 90 PSI that most air tools require. I got to set it 100 now, but 90 PSI that [clears throat and cough] 90 PSI that most air tools require. This is our lubricator. It's under pressure, so I can't open it. But this is super nice. You just add in your oil right here, adjust your flow, and you can add oil right to your line. So, that's super nice. So, moving on, get down low here. See if we can get a couple pictures of the drain for you guys. So, [snorts] down here, we have a 2-in to 1/2 in bung, or not bung, bushing. My bad. And then we have a 8 in half inch Black iron two and a half inch valve works perfect. I was going to throw a auto drain on there for like 30 bucks and I still might, but I'm not going to use this compressor that much to justify having the auto drain. So, it needs a paint job. It needs all the stickers peeled off. But, yeah, I'm I'm happy with it. it it pumps up and it works. All right, ignore my shitty handwriting. Let's talk prices. So, we have our 5 horsepower Harbor Freight compressor pump. This bad boy that I for the big black twin cylinder back there, that was $240. Now, with a 20% off coupon like they're running this weekend, this weekend as in December 13th or whatever it is today, um you can get this cheaper. You could probably get this for $200 roughly. And then EMZ motor, 5 horsepower, singlephase, 230 volts. I picked it up for roughly $290. >> [snorts] >> You could go with a Viva Vivore 5 horsepower singlephase for like in the 170 range. You could also go up to like a Century or um I forget whatever name other names are up in the 500 $600, 700 range. You could you could go crazy with the motor if you wanted. I've heard bad things about the Vivore. I've heard all right things about the EMZs. The Centuries are pretty good. So, you get crazy with this. This is just what I went through. So about 300 bucks that was shipped to my door. And then this jumper hose here, the 3/4 in jumper hose, MPT, was $34 on Amazon, which in my mind is a little bit cheaper than buying all 3/4 in black iron. Then you have a 3/4 in compressor check valve. That was the one that this line goes into. That was $18 on Amazon. You can get that size, whatever size you want to get it. I just went 3/4 to 3/4 because that's what I wanted. Our electrical portion of a compressor, so I got 13 ft of 10 gauge is $2.64 a foot. You can get that cheaper, I'm sure. And a 30 amp plug. The total was $51 for our electrical. Now, if you go shorter plug, cheaper, whatever, 10 gauge, whatever, you can get that down. Our intake, we're going to skip here. We're going to stand intakes. Our intake was a two 2 in to 3/4 in bushing and a 90° elbow. That combined was $10. Picked that up my local plumbing store. All right. Now, our drain, the one at the bottom of the tank, that was a 2 inch to a half inch bushing, 8 inch by half inch black iron pipe, 1/2 in 90/2 in valve, that was roughly $24. And that's up here at Ace Ace Hardware. We don't have a Home Depot or nothing. So, if you had a Home Depot or a Menard's, you could certainly probably do that cheaper. All right. Next, the belt I got at AutoZone. was $11. And that's really about it. Oh, I guess our I should add on here. Our pulley for our motor was $20 on Amazon as well. So, our pulley was 20 bucks. So, about $310 for the motor setup. Um, and that's just what you would find at the store. That's what the big compressors come with, right? Doesn't come with a lubricator. Doesn't come with a regulator. Doesn't come with any fittings. All it comes with is this. Now, the metal for me was free. It was some scrap stuff at work, so I didn't worry about that too much. But you could get the metal for probably 50 bucks. It's It's not much metal at all. So, you get the metal for 50 bucks. Or you might already have a compressor that will work with this. Mine didn't. You might not even need the metal. So that's give or take whatever. So total with everything not including the regulator was $690. The Harbor Freight lubricator and regulator ran me 80 bucks. So it brought the total to $770. So, for roughly $800, I have a 15 CFM two-stage compressor, 60-gallon tank with a lubricator, with a regulator, with the fittings. All it took was a little hard work and we got it done. Now, this whole thing cost me roughly $800. Could I have built it cheaper? 100% I could have built it cheaper. Could have went with the 3 horsepower motor. Could have went with a 3 horsepower pump and that would have ran me way cheaper. I didn't even do the math on that cuz I haven't done it yet. This could have been a/ inch line instead of 3/4. Our fittings down here could have been 1/2 in instead of 3/4. This could have been just a mini regulator and not a lubricator. And then you just add oil to your airline. Um, so there's a lot of things that that I could have done to make it cheaper, but I'm happy with the setup that I have. Now, on the flip side, there's a lot of things that could make this build more expensive. one being a better motor, maybe not a Harbor Freight pump, but mostly if you guys didn't have this already, this is But yet, this is like a hundred bucks. You can buy one of these at Harbor Freight for probably 20 bucks. This is 20 bucks at Napa. Um, so 900 bucks, you could have had a full compressor. And even so, even if you could not find a tank or you didn't want to find a tank or you didn't trust the tanks that were for sale near you, 550 bucks will get you a new 60-gallon tank, maybe even an 80 gallon tank. So, there are there are a few things that I would change about this compressor, about this build. If if if I were to build this again, there are a few things I would change. I would change one, I would plan my build a lot better. I ended up having to cut a hole up here because my fittings down here for my intake didn't fit. So, I would have raised this up a little higher. Um, I maybe would have went with the three horse instead of the five horse, but there was a restocking fee. I didn't want to pay the restocking fee. Um, solely just to cut cost, just to cut weight. Um, I'm not mad at the the thing I did, but that's one way you guys could. Um, I definitely would have cleaned my tank out a little bit better before I built things, like removing this bung. I actually removed this bung two days ago to get this to fit. So, I welded everything together, mounted everything, and then I had to take this bushing out. Bushing. Bushing. Bushing. Not bung. Bushing. Then I had to take this bushing out. pain. Um, I maybe would have put the compressor on a skid or on wheels or something. Made it a lot more maneuverable. Um, I would have done all of my drain work on the bottom before I did my top work. I just I just would have planned the I would have sat down and planned the compressor a lot better than what I did. Um, it it turned out, but it just the [clears throat] building building wise, it would have been a lot easier to plan it all out. And that that happens with everything you build for the first time. If I were to build another one of these again, it would take me half the time. Um, and then finding this was another pain. So, just know that this fitting is just MPT. That's all it is. It's I'm sure someone out there is going to tell me something differently, and maybe it is something different, but I found that MPT works fine. So, do you need this compressor? Do you need this compressor? The average person? No, probably not at all. Um, you'd probably be fine with a DeWalt with an Ingresol Ram with a Quincy at whatever. A DeWalt or an Ingresol Ram at Tractor Supply for 700 bucks on sale Black Friday, you'd probably be fine. 10 CFM, it's going to run your die grinder. It's going to run your belt sander. It's going to run your DA. It's going to run them fine. Um, this gives me a little extra security in running these things. And honestly, for the price, it cost me $7 $800 to build this to this size [snorts] as where it would have cost me $7, $800 for something a little smaller. Now, if you're just doing bike tires or car tires or just a simple die grinder every once in a while, you probably don't need this. Um, but doing uh custom fab work. I got the one one ton axle swap coming up and the J20 build that I got to start on again soon. Um, I figured I'm going to switch over to air. I'm going to try it. I got a lot of electric tools and I know Milwaukee makes a DA sander and they make a belt sander and they make all these tools, but you're looking at $1,000 for four tools as where I got four tools in a compressor for under $1,000, right? So, I don't mind the air hose. We're going to see how it goes. I've always wanted to build one of these, so I went ahead and did it. Um, do you guys at home need it? Maybe you don't. Just just think about what you want for your air supply before you commit to a project like this because Harbor Freight's got some good air compressors in the 67 CFM r. I think it's 5 point something. I have to check again. Um in the 5 CFM range that would get you by just fine. And Tractor Supply has got the 10 and 11 and 12 CFM ones for roughly the same price. That would do it, you know. But if you want to get into the two stage 15 CFM 5 horsepower 220 volt, you're looking at $1,800. I built this for $800. You're looking at $1,000 less. Um, so yeah. So, one upgrade that I am considering doing is bigger pressure switch. Get this tank up to 175. I think it would like me a lot better. Um, this works for what I need it for, but once I add a paint spray, I'm going to have to do an air dryer. Um, the drain, automatic drain at the bottom, I might change that out and plug it into an automatic drain. I got to build my belt guard yet. Um, other than that, I don't think I would change a thing. The six minute stress test taught me a lot of things about this compressor and how it's running. Um, I had a little bit of an issue building past 110 PSI after I ran it. So, my cutin pressure is 90 and my cutout pressure for the compressor is set at 125. That's just what the pressure switch was set at when I bought it. It came on the tank, so I didn't change it. I know I talked about in the video changing it out. think I'm going to. And here's here's why. So, it has a problem catching up with the demand of the air tool, which I don't know why, but what I think is that you pull air at 90 PSI. So, the tool is pulling air at 90 and that tank immediately drops below the cutin. Now, the [snorts] compressor is running at 100% duty, but there's no pressure buffer. So any small flow deficit shows up instantly. You can see it right. Um there's there's nowhere for pressure to recover. Now how how it's supposed to work is that the tank stores the high pressure energy. So it stores above that 90 PSI. The regulator regulates down to 90. The pump puts out 15 CFM. The tool demands four to six CFM. So essentially excess air in the tank is what recharges the tank. The tank pressure stab stabilizes instead of it collapsing it, right? Um the tank becomes the buffer basically. So when you have it and it cuts in at 125 and cuts out at 150, you're giving that compressor a head start already. When it's cutting in at 190 and cutting out at 125 and the tools running full balls at 90, you it's just not going to keep up. And and you would think it you would think it would because the compressor is at 15 and the tools only at four. So why 15 is bigger than four, right? Easy math. Um but another thing that you got to realize about two-stage compressors is that they run most efficient at a higher discharge pressure. um they lose effectiveness when they're forced to live around that 90 to 125. And they're designed for the 150 to 175 range. So, I think I'm really limiting my pump by not having it set at the 125 to 150 range. And I wish I could go up to the 175, but my tank just isn't rated for it. So, I want to jump on here and show you guys and and explain why that was happening. I am going to switch out that um pressure switch here to adjustable one. Set it at 125, have it cut out at 150, and I'll keep you guys updated how that works out for me. But yeah, so enjoy the rest of the video. I just want to jump in and say that. So, as you guys saw with the stress test there with our 6- in sander, um I think this pulls roughly 4 CFM. Um it took about a minute to drain it from 120 down to 90 and then to bring it back up to 120. We were at the 5minute mark and it it it couldn't really push past 110. If you guys have any ideas in the comments on why or if you guys have any ideas, drop in the comments why it's not getting me past then. So, that's my compressor build. I'm going to get out of here. I got to work on. And remember, like always, you're not living unless you're living lost. Peace.