An electrical question about compressors

[Denee007]

Hi, it's been a while since I've posted, but I've been looking at compressors for my newest location. My old sears compressor just isn't working very well especially for occasional cabinet blasting and especially with a HVLP spray gun. I'm perplexed on new compressors in the 5hp/60-80 gallon size. Reviews are like on Amazon, good and bad on everyone I look at. The new ones are so pretty, but have some issues, so I thought old might be better?

So, started looking at older compressors and one popped up on CL. However, it's 3 phase! the man say it's a good compressor(yada yada),but it's 3 phase(I said that). So what can be done if anything?? Can one switch out a 3 phase motor and put a single phase motor, or would that be terribly costly?
dne'

https://houston.craigslist.org/tls/d/cypress-5-hp-air-compressor/6898830813.html
also found this in Dallas:
https://dallas.craigslist.org/dal/tls/d/kaufman-2-champion-air-compressor-5-hp/6885732580.html

 

[pajibson]

Last time I did it it wasn't too bad. Cost of the motor isn't really the issue. Long term cost of electricity and making sure you have a circuit strong enough is what I would look at. Tractor supply has some IR units at a fairly reasonable price

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[Wrench97]

Depending on the motor frame and shaft size a 5hp will run between $200 to $500 and run on a 30 amp circuit. I had to convert my 5hp Saylor Beall over to single phase when I bought it. I paid $425 for a 184T frame unit worst part was the 3 phase motor that was on it was like new and took 3 months to sell for $75..........................

 

[The Cobbler]

as noted above, the cost for a single phase motor , will it be worth it?
is the price negotiable?

 

[930dreamer]

I like the Champion with the heat exchange/cooler.

 

[foghorn1966]

I would suggest having a read through the Sticky at the top of the page on VFDs
https://www.garagejournal.com/forum/showthread.php?t=320064

 

[dr_clyde]

I just made sure my shop has 3 phase power.

In all seriousness, if the compressor in question is 5 HP or under, you can pretty easily find a single phase motor to use in place of the 3 phase motor. Just match the RPM and HP, and make sure you have a circuit capable of running it.

You can also just run a VFD, which would be a better solution than swapping out the motor IMO.

 

[Denee007]

Thanks guys! I'm pretty serious about the Champion in the CL ad, not terribly far from here. I'm leaning towards the 80 gallon unit, however would probably be happy with either

https://dallas.craigslist.org/dal/tls/d/kaufman-2-champion-air-compressor-5-hp/6885732580.html

 

[The Tool Tyrant]

Thanks guys! I'm pretty serious about the Champion in the CL ad, not terribly far from here. I'm leaning towards the 80 gallon unit, however would probably be happy with either

https://dallas.craigslist.org/dal/tls/d/kaufman-2-champion-air-compressor-5-hp/6885732580.html

Good choice! The 80 gallon also has Champion's industrial grade pump (R15-B) which has disc valves rather than reed valves as the one on the right (RV15A) is equipped with.

 

[dr_clyde]

The pump is the most important part of a compressor. Don't get all wrapped up on tank size, its not near as important.

Look for high CFM and pressure. If you have high enough CFM and pressure, you can use a smaller tank with better results.

All a large receiver does is make the compressor cycle less often and provide a buffer.

 

[Denee007]

Thanks Tool Tyrant and Dr Clyde I just spoke with the seller of the compressors in question. He says for my purposes the 60 gallon would be perfect. He says even the "radiator" cooler on the larger tank, doesn't work as well as most would think they do. He says yes, the condense but the condensation goes right into the tank. Also the pumps on both are the same output cfm wise. That being said, I'd probably be better off with the 60 gallon. I'm silly excited about either one and not having to deal with today's NEW compressors. Plus he said parts are readily available and all he does is work on compressors.
So, if all goes well, I'll have one of them here Saturday around noon! Getting it off my trailer will be no problem, however moving to an ideal spot may prove interesting. I think my neighbor has a front end loader on his tractor, but read somewhere for safety, just to remove the pump/motor?
dne'

http://www.classiccarsandtools.com/2019/03/06/gantry-crane-taller-is-better/

 

[mike93lx]

Be careful about advice from people trying to sell you stuff....

That said, yes, take the motor and pump off, if possible. They are very top heavy.

 

[Denee007]

Yeah Mike, I seem to fall for "sales" pitches, too trusting I guess

I'm still partial to the larger compressor, it just looks awesome! Yeah yeah, size doesn't matter, but it just looks 'commercialish'.



This looks like the perfect place for one of em.

 

[Denee007]

The 80 gallon just looks impressive, the 60 gallon~ the way it bolts/attaches to the floor looks~ weird. The larger one is 1275, 100 more than the 60 gallon.

 

[Leaflessshadetree]

I'd pay $100 more for the 80 gallon.

 

[dr_clyde]

Yeah, for only $100 more I’d get the bigger one too.

They both will be more compressor than you need I suspect.

 

[Denee007]

Thanks Leaflesssshadetreeguy and Dr Clyde
If the compressor works as well as I hope, I'll be getting more air tools; air polisher, angle grinder, a better die grinder, I'm sure there are other things, but I can't wait to be able to use my media cabinet without having to stop for air to catch up!

 

[stonesfan68]

Pay the extra $100 for the bigger tank. In the compressed air world you’re hard pressed to have too much storage.

 

[Denee007]

If the seller still has the 80, I'll get it

Whereabouts are you in Houston?

Pay the extra $100 for the bigger tank. In the compressed air world you’re hard pressed to have too much storage.

 

[NoMoreGreen]

I saved his contact info. I happen to be in the Dallas area and will be buying a compressor next year. I am curious to see how your deal goes!

Nmg


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[The Tool Tyrant]

As I stated previously, the pump on the 80 gallon is a much better pump than the one on the 60 gallon. The RB15-B (80 gal) pump is $200 more to purchase than the RV-15A pump (60 gal). WELL worth the extra $100 PLUS a larger receiver! It's a no brainer.

 

[Denee007]

NMG, just watch this thread and I'll post what happens And Tool Tyrant, how do you know so much about these old compressors, but as it stands, I'm definitely going for the larger compressor
I just hate this waiting thing for Saturday to get here; I'm probably like most, fear that someone's going to get there before I do! lol

I've spoken to the seller a couple times, and me, I've never met a stranger, so I get along with him like he's a good friend.

If all goes well, he will load it on my 5x8 trailer in kind of an angle to keep the crankcase oil from going where it shouldn't, I'll strap it down. He talked about possibly loading it standing, but sent shivers up my spine seeing that in my rear view mirror, I don't think so! At home, unload it with my gantry crane, I plan to remove the electric motor/pump to get the unit in the area where I want it, the re-assemble of course. I'll more than likely be doing this alone. My husband is still under doctors care after his total hip replacement; I wouldn't want him to mess that up!
dne'

 

[The Tool Tyrant]

To answer your question...I have rebuilt my share of pumps as a hobby and for friends. I've spent a lot of time doing my research before I ever spent any money purchasing a used pump as a 'rebuild candidate' and I own WAY too many compressors...seriously too many! Personally, I would only consider Quincy QR 325 series, Champion R15 B series or Saylor-Beall 705 as they are 3 great pumps, the right size for probably 75% of compressed air users AND they're easy to work on AND last but not least, their all made in the good ol' USA. And BTW, those compressors are not THAT old!

Good luck and take your time get'n her home!

 

[Denee007]

Hi! Made it back with the 60gal compressor, the 80gal was sold already but I'm very pleased with the 60gal. Someone had called and ready to come out to get the 60g but he said it was sold(to me of course). I hadn't said that I wanted the 80,but even he can't take the word until money is in hand. The seller(Greg) was incredible, I stayed for a bit and had a cup of coffee discussing compressors and even discussed physical therapy for his back and other ailments, but it was like talking to a good friend

Greg did plug it in and I was delightfully pleased how quickly it pumped up and especially how quiet it is! It turns at 1750 rpm. He loaded it for me and helped me make sure it was secure for its journey back to Cypress, Tx.

At home, I had a difficult time getting the compressor upright so I removed the heavy pump with my gantry crane to lighten the top end. Then used my gantry crane to stand it upright, lifted the tank/motor, then rolled the trailer out from underneath it.




I used my Little Mule (patient lift) to remove motor, they're both pretty darned heavy!


Since I have it apart, I plan to go ahead and paint the tank to match the pump in original Champion green, Gregg gave me the paint info., so I can take care of that next week some time.



So, the story isn't over as I haven't put it in service, but he stands behind his work and is there if I need help or advice. I'm pleased to have met him.

Thanks everyone~ I'll keep updating this as I go along!
dne'

 

[The Cobbler]

Nice!

 

[The Tool Tyrant]

Congrats !

Take your time setting it up. Be sure to use a straightedge across the pump pulley to motor pulley to verify the belts are inline. Be sure the drive belts are properly adjusted.

BTW, it's the motor that runs @ 1750 RPM, the pump turns quite a bit slower than that. To get the pump RPM, measure both the drive (motor) pulley diameter and the driven (pump) pulley diameter , next divide the drive pulley diameter by the driven pulley diameter, lastly, multiply the motor RPM by the quotient and your answer is the pump RPM.

 

[Denee007]

Thank you Cobbler, and you Tool Tyrant! I doubt I'll try to find out how fast it turns, I just know it's incredibly quiet, smooth, and pumps quickly! I'm just impressed and crazy happy to have such a machine! Though he gave me a plug, I think I'll move the compressor near my new breaker box and "hardwire" it into the box, but I forget what breaker he told me to use? double 30amp maybe?
Anyway, I have the paint coming for the tank, and new feet pads, but limited this week to do very much; Jury dutyfor one, plus we're working on two of our rent homes to sell(almost a full time job), so I'll keep this thread going until completion
dne'

 

[Denee007]

While I have my compressor apart(it's easy to get to even when together), would it be advisable to install an After cooler, the copper line going into the tank? Looks like it'd be easy enough

https://www.ebay.com/itm/CQP14773C-...COOLER-3-4-TUBE-R30B-R30D-PL30A-/292047470365

 

[Prybar]

It really depends on your air needs. I personally like the aftercoolers. Yes, they drop the condensation right into your tank, but then it can be drained out. If you have an auto drain it drains out pretty darn easy in fact. It won't take care of all of your moisture in air issues but it does help a lot.

 

[Denee007]

Thank you Prybar I would be using my blast cabinet a lot and of course spraying paint, and plan to get a air polisher.

I had seen this(below) and just never sought out a youtube of it, it looks like something I could do, but still I can put in anything to reduce moisture.

dne'

 

[strutaeng]

Hi! Made it back with the 60gal compressor, the 80gal was sold already but I'm very pleased with the 60gal. Someone had called and ready to come out to get the 60g but he said it was sold(to me of course). I hadn't said that I wanted the 80,but even he can't take the word until money is in hand. The seller(Greg) was incredible, I stayed for a bit and had a cup of coffee discussing compressors and even discussed physical therapy for his back and other ailments, but it was like talking to a good friend

Greg did plug it in and I was delightfully pleased how quickly it pumped up and especially how quiet it is! It turns at 1750 rpm. He loaded it for me and helped me make sure it was secure for its journey back to Cypress, Tx.

At home, I had a difficult time getting the compressor upright so I removed the heavy pump with my gantry crane to lighten the top end. Then used my gantry crane to stand it upright, lifted the tank/motor, then rolled the trailer out from underneath it.




I used my Little Mule (patient lift) to remove motor, they're both pretty darned heavy!


Since I have it apart, I plan to go ahead and paint the tank to match the pump in original Champion green, Gregg gave me the paint info., so I can take care of that next week some time.



So, the story isn't over as I haven't put it in service, but he stands behind his work and is there if I need help or advice. I'm pleased to have met him.

Thanks everyone~ I'll keep updating this as I go along!
dne'

Congratulations! That's a sweet compressor. Is this seller by any chance in Kaufman? I've seen several of his ads, and he sells top quality machines, mostly Champions. His prices are very reasonable too.

By they way, I wouldn't recommend that aftercooler contraption on youtube. I found a Champion aftercooler on Ebay for like $80 several years ago. It's actually made for this purpose. It mounts on the belt guard in front of the pump flywheel/fan, much like a car's radiator. All of those copper tees and fittings will cost an arm and a leg, plus you have to spend time to solder all of that.

Unless you have free copper and fittings (and a lot of time to kills,) just buy an aftercooler.

 

[Denee007]

Thank you! Yes, the seller is in Kaufman and his name is Greg. He is incredibly nice and just a good guy; honest. He assured me that an Aftercooler isn't necessary as the moisture just goes into the tank and drained occasionally. But, it looks "easy" enough to do and may sound dumb; but looks neat! My compressor doesn't have the belt guard and would rather not have one, but mounting the after cooler would be a little more difficult. Perhaps I could mount it on the other side and put a fan on it.
dne'

Congratulations! That's a sweet compressor. Is this seller by any chance in Kaufman? I've seen several of his ads, and he sells top quality machines, mostly Champions. His prices are very reasonable too.

By they way, I wouldn't recommend that aftercooler contraption on youtube. I found a Champion aftercooler on Ebay for like $80 several years ago. It's actually made for this purpose. It mounts on the belt guard in front of the pump flywheel/fan, much like a car's radiator. All of those copper tees and fittings will cost an arm and a leg, plus you have to spend time to solder all of that.

Unless you have free copper and fittings (and a lot of time to kills,) just buy an aftercooler.

 

[Denee007]

Just looking at compressors, most just have the 1/2" copper tube going directly into the tank, a few show a finned tube which could be nice if I could find one. Can't find those "extruded finned tubes" anywhere. However, I was thinking to just go ahead and replace my pump to tank copper tube with a long piece, perhaps with a coil or two, a loop. My copper piece looks a little flattened, not bad, but could increase resistance thus heat? lol Too much physics here.
me of course

 

[strutaeng]

This is one that you posted is the one that I bought for mine also:

https://www.ebay.com/itm/CQP14773C-...COOLER-3-4-TUBE-R30B-R30D-PL30A-/292047470365

Yours is a 2-stage, with that finned tube going from 1st stage to 2nd stage. It's called an "intercoolder."

Mine is a 1 stage with a little 30 gallon tank and that aftercooler. I have done body spray paint and have yet to have any problems with moisture. My compressor lives outside under a tarp, LOL.

I also have a one of these double air filter gadgets at the end of a 1/2x50' hose, but it has never had any moisture in it. Now, I do get water in the tank, but just drain it often.

 

[The Tool Tyrant]

Denee, even if you don't add an aftercooler, I would suggest replacing your supply line as I see it somewhat kinked/ flattened at the bend and a nice big dent in it further down the tube. You sure don't want any unnecessary added restriction in the line.

If as you stated, you will be painting with your compressor, you most surely want to remove as much moisture from the air as possible. If the air going into the receiver is hot (steamy) you can't remove the moisture and it will find it's way to your paint gun (or pneumatic tool). When you utilize an aftercooler, the moisture condenses and the droplets run to the bottom of the receiver to be drained off, either manually or automatically.

 

[Denee007]

I was waiting for you to chime in! Yes, I'm definitely going to replace that copper line (pump/tank), it is flattened. That still leads me at a while I'm at it making the after cooler
Any idea how hot that line gets?

I was looking on ebay(where else) at stuff, and this seems interesting, but can't tell how large or small the tubes are. I wrote the seller, but don't expect to hear back. I could put a thin radiator fan 12v to 110v, just thinking out loud
https://www.ebay.com/itm/263280347390?ViewItem=&item=263280347390

This particular compressor has the finned tubing, couldn't find anything like that

Denee, even if you don't add an aftercooler, I would suggest replacing your supply line as I see it somewhat kinked/ flattened at the bend and a nice big dent in it further down the tube. You sure don't want any unnecessary added restriction in the line.

If as you stated, you will be painting with your compressor, you most surely want to remove as much moisture from the air as possible. If the air going into the receiver is hot (steamy) you can't remove the moisture and it will find it's way to your paint gun (or pneumatic tool). When you utilize an aftercooler, the moisture condenses and the droplets run to the bottom of the receiver to be drained off, either manually or automatically.

 

[The Tool Tyrant]

Denee, regarding temperature differential, I checked mine with an IR temp gun after I installed it and it was substantial, but I don't recall exactly what it was. I do know that I could hold my hand on the tubing post the aftercooler but no way could I touch it pre- aftercooler. I'll shot it tomorrow and let you know.
Personally, I believe Saylor-Beall has the best set-up for compressor mounted aftercoolers. They use a fan mounted on the motor shaft, so the fan is turning at 1725-1750 RPM vs 700-800 RPM of the fan on the pump pulley. Here is a link to their video showing the set-up in which he discusses the temperture differential http://www.saylor-beall.com/saylor-beall-air-cooled-after-cooler/

The short finned discharge tube in the photo you supplied probably helps a little (very little), but not nearly as much as a larger unit mounted next to the pump pulley would accomplish.

 

[Prybar]

The aftercooler on my compressor is very similar to the Saylor Beall in the video. Mine is mounted on the pump side but I believe plenty of air flows through that area and it gets the cold air before the pump does. I get about 260* discharge temp at my output line right after the small cast iron pump mounted after cooler. About *250 going into the rear mounted auxiliary aftercooler and the discharge into the tank is darn near room temp. At least, its imperceptible to my hand. I also have a copper tube condenser unit mounted on the wall before the regulator with drains. With both of these things I have no issues at all with water in the air lines and my desiccant lasts forever in the paint booth.
Here is a picture of my condenser. I just re-mounted it to the wall and have only temporary plumbing hooked up to the compressor.
View media item 93239

 

[Denee007]

Thanks guys! Just got back from jury duty I'm just trying to be a miser here, like all of us are, and this intercooler below~ The one shown is an 16 passage with a 12v fan which I could mount remotely, somewhere strategically and a water filter(?), they also make an 8 passage too. However I'm confused with the AN's and fitment on my pump/tank.

And thank you TT (tool tyrant), the Saylor-Beall AC (after cooler) is awesome, but I think their price may be a little out of reach. And yes, I agree the shorty
fin would probably do nothing.

And prybar, I like your condensator moisture extractor(just made that up, and I could do that

The ebay seller did write back! "This item has a -8AN inlet and outlet, which is the equivalent to 1/2" in AN." I don't know how that translates into the pipe fitting on my compressor.

And this one being the lesser of tubes, a fan could be mounted on it as well.
https://www.ebay.com/itm/Derale-Oil...m=282707836633&_trksid=p2046732.c100040.m2060

This one is 149.oo free s/h

 

[Denee007]

5/8 line!

I got to thinking about the line pump/tank, I thought it was 1/2" but looks to be 5/8", which is good I suppose, but erases my last two posts of ideas.

I did receive my paint for the tank! May can start on that soon