just bought my first "real" compressor - is it too big?

[CamaroMan]

I bought this today for $200 from a moulding factory that upgraded theirs - $200 deer.. im pretty sure its way too much? it ended up being ALOT bigger than i thought in the pics

Its a 120 speedaire thing thats the size of a alpha male reindeer - im a little afraid of it, not to mention my knowledge of electronics is 12v sparks, 220v explodes.

Here it is:

 

[CamaroMan]

Too add - yes dunce that I am learned I cant run it unless i change the motor out to single phase cos we have single @ the shop :/ soo not sure what to do. Re-sell (and buy a smaller single phase unit like 1 60 -80 gal) / convert motor on this one? All i do is sand blast boat parts, carbs and stuff - occasionally, maybe once a month..

What u guys think? Keeper?

 

[cnttxmdc]

You can actually get a phase converter for a decent price. That looks like a really good compressor. You may check into that before you do anything else.

 

[cnttxmdc]

Thinking about it more, a 15 hp motor or phase converter isn’t going to be cheap... if I were you I’d put it on craigslist for $500, and see if you get any bites. As long as you sell it for $200 plus your fuel, it’s free education.

I’m a sucker for a great deal too, so I totally understand coming home with something way bigger than I need!

 

[CamaroMan]

You can actually get a phase converter for a decent price. That looks like a really good compressor. You may check into that before you do anything else.

can u supply me with an example? no idea where to start / what price

 

[LXCam]

When I read the title I jumped in here to say "STFU, this is garage journal "



But ya, you bought waaaayyy too big. Don't even screw around with it. Sell it as is and move onto something a bit more manageable for a residence. This one is not cost effective to make work no matter how you go about it.

 

[M6erfan]

When I read the title I jumped in here to say "STFU, this is garage journal "



But ya, you bought waaaayyy too big. Don't even screw around with it. Sell it as is and move onto something a bit more manageable for a residence. This one is not cost effective to make work no matter how you go about it.

Lol, I agree. My first reaction was "NEVER TOO BIG!"

But yeah, thats a big 'un.

 

[marineman]

Yeah it's overkill but that's what this site is all about. I'd still sell it though. Lots of used 3 phase equipment out there for pretty good prices but it's not worth the hassle to me.

 

[jumbojak]

You got a good story out of it either way. Building a phase converter to run it would be a better story, but this is a good one either way.

 

[nmantas]

Degrease it and make it look pretty and sell it to make a few bucks. The only issue would be you can't fire it up for the buyer but you should be able to make a few bucks.

 

[CamaroMan]

we are gonna test run it at my buddies shop 2moro and ill make a short film - yeah i think selling it at this point makes most sense. What size do u guys recommend? 60/80 gallon? I just do occasional sand blasting - no truck tires to fill here..

 

[doan]

You "could" run it on 220 maybe on a 60 amp breaker with a BIG phase converter

OR

Put a 3-5 HP single phase motor on it and change the pulley size. Might end up with a good quiet air compressor.

 

[PT Doc]

3 phase has messed up lots of people in the past and will continue to jack people up in the future.

 

[mvusse]

3 phase has messed up lots of people in the past and will continue to jack people up in the future.

Whereabouts are you at? I have a single phase 6HP 80 gallon upright if you'd trade straight up. 175psi, rated at 100% duty cycle..

Your compressor is bigger than I need (the 6HP has always worked fine for me, as well as the 5HP it replaced), but I have 3 phase available in my shop.

 

[American Locomotive]

That compressor would not be easy to run off single phase. You'd need a quite large phase converter, and a minimum of an ~80 amp circuit to run it and the phase converter. Probably closer to 100A all said and done.

If you can post more pictures of the compressor pump, there is a chance you could spin it slower. Compressor pumps are usually rated at a variety of horsepower levels depending on how fast you spin them and what pressure you operate it. There's a chance you could run it slower, off a 7.5HP single phase motor.

 

[6PTsocket]

Even re motoring it has problems beyond the obvious one, cost. I am not sure you can reasonably run more than around 7 1/2 hp on single phase 230. I don't know if they make the motors and the current requirements are really getting up there. Those that know a lot more about compressors than I do would have an idea of the minimum size motor that would turn that pump. You might even need to change the pulleys. 3 phase motors are more efficient than single phase but even if you convert to 3 phase, you still have to put in quite a bit for 15 hp.

Sent from my SM-G900V using Tapatalk

 

[Mr_B]

Yeh clean it flip it for few buck profit and buy something single phase and smaller .
Good compressor but simply not good for you .

 

[seber]

I ran a similar unit for years on single phase. I replaced the big motor with a five hp and a proportionately smaller sheave. It makes for an extremely reliable and very quiet compressor. In addition you get a huge reserve for sandblasting. You may have to do some searching to get a good price on a used motor but with some effort they can be had pretty cheap. Don't forget to figure in the cost of sheaves, pulleys and motor starter. I had used motor starters but I don't know how easy used unit would be to source.

 

[John in OH]

Yeah, I agree with most above that it is too big ... although I'm usually a "can't ever be too big" guy.

IMHO, a 3-phase 15 hp compressor will probably need about a 20hp rotary phase converter ... a static converter probably won't work on a hard-start machine like a compressor. And a 20hp converter at 240v will take more than 41 amps.

Clean it up and sell it. Use the money you get and buy a nice, new 5 -7.5 hp, 240v, single-phase compressor with a 60-80gal tank. Much better for home use.

 

[930dreamer]

Yes clean it up if you want to sell it, you won't be able to run it for a buyer though. I'd start at $1000 and work on offers.

 

[Hdonly0]

Five hp single phase motor. Smaller pulley on the motor. Adjust the cut-off pressure down. You can use the three phase starter on single phase. It will last you the rest of your life.

 

[sberry]

This is a classic case of opinions vs decent advice. It should be obvious that the poster doesnt know squat about this,,,, thats not about him but others that cant help themselves, most likely compulsive junk collectors, not all but some.
Anyone telling you anything but to clean and sell this monster (reason it sold for 200 in the first place) and buy something something common can be plugved on to the simple electric service and ready to use is doing him a great disservice.

 

[sberry]

My advice would be different if a guy came here and said,, I need 15 hp comp with big tank, I am running a truck tire service center, willing to invest hundreds, have the ability to convert the equipment, dont care how hard it is, how long it takes and how much it costs,,, then, yes, this comp is for you.

 

[hoston23]

would be more cost effective to get a single phase motor than a phase convertor, those phase converters use lots of electricity when converting,

 

[Hdonly0]

Been running this one that was originally 3 phase just as I said. It has been doing a fantastic job for 12 years now. No problems at all.

 

[930dreamer]

would be more cost effective to get a single phase motor than a phase convertor, those phase converters use lots of electricity when converting,

Phase converter is sized at double the hp of equipment you want to run. So in this case a 30 hp idler running on 240 V and you would have a great compressor setup.

If the OP really wants to run this compressor, ignore everyone and research how to make it work.

 

[CamaroMan]

thanks guys - i JUST did some reading on spraying and it seems spraying HVLP guns requires alot of air.. Since we have a boat repair shop its not wrong to say perhaps in the near future we might be doing pretty big spraying jobs.. Ill be reading thru all the suggestions - maybe the 5hp modification will work.. as mentioned im not very clued up on compressors - i know 3 phase vs single, but not the limitations etc.

u guys have been a great help -

fyi we are going to run the compressor at my friends shop - if it works ill look at cleaning it up / selling for profit - OR modifying it to take advantage of the tank size with a smaller motor.

 

[CamaroMan]

I ran a similar unit for years on single phase. I replaced the big motor with a five hp and a proportionately smaller sheave. It makes for an extremely reliable and very quiet compressor. In addition you get a huge reserve for sandblasting. You may have to do some searching to get a good price on a used motor but with some effort they can be had pretty cheap. Don't forget to figure in the cost of sheaves, pulleys and motor starter. I had used motor starters but I don't know how easy used unit would be to source.

Hi - Im deciding to possibly keep it and convert it, we are a small boat repair shop in CA and I might be doing HVLP spraying - maybe this compressor CAN work -

If i downsize the motor, should I just sell the old one? And where do the sheaves go? Im a engine/boat mechanic so not too dumb with mechanical things, just need some information to get my old brain working -

thanks

 

[CamaroMan]

Jut got off the phone toa shop with a bunch of used compressor parts. Guy says he has a complete motor and pump 5hp that will run on 220v for a very god price.. Maybe I can attach that on top of my tank and sell off the motor and pump on mine..

 

[highland512]

You might be able to "trade in" your motor toward the 1ph motor. If I was in your boots I would swap the motor and pulley, keep your compressor and tank and dont look back. You will never have to worry about air usage or replacing your compressor for as long as you will care about it. If you have multiple HVLP guns or a sand blaster going you will want this compressor.

 

[LXCam]

Jut got off the phone toa shop with a bunch of used compressor parts. Guy says he has a complete motor and pump 5hp that will run on 220v for a very god price.. Maybe I can attach that on top of my tank and sell off the motor and pump on mine..

That would work just fine. You'll need to drill and slot new mounts but that's no big deal. Just don't fall for thinking you can use the existing compressor with a significantly smaller motor. There is a reason it takes 15hp to turn it. Also don't forget you'll need a new magstarter and heaters (overloads) for the new set up.

 

[CamaroMan]

Also don't forget you'll need a new magstarter and heaters (overloads) for the new set up.

Hi - thanks for the info - sorry for my question but what a magstarter & heater and what do they do, would my old one have these / can i buy generic stuff and do i need to size/spec match it to the replacement motor? Any pointers ito what i would want to look for?

Maybe the guy can help me with these parts -

So 5hp motor/pump setup ? Ill weight the pros/cons vs running this one and selling for an 60-80 gallon or modifying..

 

[Citation]

How much for the 5hp motor and pump? It's it a good pump?

I would get the model number of the pump and see if it will run on a 5hp (unlikely) or 7.5 hp (possibly) motor. Then look at how much either of those motors cost. I would not replace the pump and motor. At that point just get a different compressor. You should have no trouble getting your money back or even making money on this if you clean it up. It doesn't make sense to rebuild this into a 5hp compressor when you can probably buy a used one for less.

 

[kenc184]

You don't NEED a phase converter or a VFD - both of which are not financially or electrically practical for a 15HP motor - yes they are more convenient but just rig up a simple 110v single phase pony motor to start it.
Of course you're still going to need one big *** breaker for that 15HP motor!

 

[Bert_]

Even re motoring it has problems beyond the obvious one, cost. I am not sure you can reasonably run more than around 7 1/2 hp on single phase 230. I don't know if they make the motors and the current requirements are really getting up there. Those that know a lot more about compressors than I do would have an idea of the minimum size motor that would turn that pump. You might even need to change the pulleys. 3 phase motors are more efficient than single phase but even if you convert to 3 phase, you still have to put in quite a bit for 15 hp.

Sent from my SM-G900V using Tapatalk

7.5hp isn't in any way a limit. Biggest common single phase motor I've seen is 15HP, 10hp is extremely common around farms.

I've wired many 20-30 hp 3Ø motors with VFD's or rotary phase converters, the largest was a 75hp blower run off a phase converter.

It's doable but most definitely overkill in this case. The big single phase motors do get a bit expensive.

 

[sberry]

No point in finding a 5 ready to go for 1/4 the cost of this brain fart when there is a harder way to do it.

 

[Packard V8]

This is a classic case of opinions vs decent advice. It should be obvious that the poster doesnt know squat about this,,,, thats not about him but others that cant help themselves, most likely compulsive junk collectors, not all but some.

Anyone telling you anything but to clean and sell this monster (reason it sold for 200 in the first place) and buy something something common can be plugved on to the simple electric service and ready to use is doing him a great disservice. . . .

My advice would be different if a guy came here and said,, I need 15 hp comp with big tank, I am running a truck tire service center, willing to invest hundreds, have the ability to convert the equipment, dont care how hard it is, how long it takes and how much it costs,,, then, yes, this comp is for you.

For true. But the OP may surprise us and educate himself as to how to use this to his advantage. As said above, he's starting with nothing but curiosity, but we all did at one time.

Yes, it's theoretically possible to run a 15hp compressor with a VFD, but that large a VFD is very expensive; as much as a single phase motor.

No, I've never seen a 15hp 3-phase compressor satisfactorily run on single phase off either a rotary or static converter. I've heard of it being done, but I've also heard of many more unhappy experiments.

Yes, it's theoretically possible to use a small single-phase pony motor to start an unloaded 3-phase motor, but I've never seen it done successfully on a compressor which has to start under a load.

Yes, it's very possible to reduce the drive pulley diameter and thus the compressor RPM and adjust the cut-off pressure downward and successfully power it with a 7.5hp motor. Most compressor pumps have a large window of RPM/CFM/working pressure.

Your opinions and results may vary.

jack vines

 

[sberry]

I wanna go up the creek to go fishing. I have a car to pull it with. Is ita good idea to buy a broke ole 32 ft boat that has 2 454's in it, so I can buy another used 350 chevy ro rig in to it.
Another analogy,, buy a F600 truck, either try to hook the engine from a Ranger in it and if that doesnt look like it eill work put the engine and trans in it. Take parts off ranger,, which a guy could buy running,, all to haul a couple bags of trash to the dump on occasion.
Is the idea to work on boats or start another hobby? Paint a whole semi with 5 hp, double bottoms, 70 ft long.
Yes, we got to start somewhere, some of us learned this the hard way. He can do it easier.

 

[LXCam]

Hi - thanks for the info - sorry for my question but what a magstarter & heater and what do they do, would my old one have these / can i buy generic stuff and do i need to size/spec match it to the replacement motor? Any pointers ito what i would want to look for?

Maybe the guy can help me with these parts -

So 5hp motor/pump setup ? Ill weight the pros/cons vs running this one and selling for an 60-80 gallon or modifying..

Simply put it's a relay. The heaters are the overload protection for the motor, like a circuit breaker. Starters have a min/max hp rating and the reason is not only who much current the internal contacts can handle but the heaters have various ratings and all though interchangeable in some cases are pretty much dedicated to specific sized starters. I'd have to imagine that whom ever you're sourcing the pump and motor from can hook you up with the right set up. But you're going to need some help wiring it in. If you're close to the inland empire and need a hand let me know. I'm a big time ex boater and all though I got nothing that floats right now, I will be getting another boat since my grand babies will be of age soon enough. So it's always good to know someone that can do a nice job on gelcoat

 

[sberry]

The op said it all to himself in his first post, its too big, too old, doesnt have the power to run it and doesnt know what he is doing. What's not clear about that?
Whats the practical solution? Buy something sized correctly, something adequate, something with the design, the engineering, safety all done that will run on his existing power? Something he could use tomorrow. Something reliable without adding another layer of complicated modified equipment.
Why do that when a guy could redesign, rengineer, size and buy all the controls, learn to wire it all, maintain 2x as many custom parts on an old tank.
Why start a simple 5 hp when he needs a puff of air when he can sock a 15 hp load on the line,,, and at this point do not know what service is abailable and if the poco would have a fit over it. Why buy a simple unit when you can do all that?