Needing an air compressor

[qmdv]

I have a 3 hp 3 phase compressor that has just developed a leak in the tank. I sold our ranch that we have owned for 38 years and will be moving to a new place that has a 30 x 40 shop with single phase.

If I were staying here I would replace the tank. If the tank was good I would move the compressor and buy a new motor or a phase a matic.

Since I need a tew tank and motor it seems best to just buy a new compressor. My needs include some paint spraying, impact tool and air sanders. looking for some recommendations. Part of me says get a 5 hp harbor freight chepo then replace it when it craps out. Other part of me says get something better

 

[Busted_Knuckles]

If you have time on your hands, have look for a high quality used unit, if you run out of time, then buy the Hazard Frought ?

You did not share what brand/model pump you have and the condition of it, that might be the ticket, find a puked unit with a bad pump, but good tank/motor ? Not sure Id bother with a phase converter, I think you can get a Wen 5hp motor for $250 ( delivered ) or less now ?, 3hp might even cost more ?

 

[Marctrees]

The desirable HF unit 93274 seems not currently available.

Marc

 

[qmdv]

What about a Puma AC https://boise.craigslist.org/tls/d/nampa-puma-80gal-65hp-air-compressor/7174189250.html

 

[sberry]

That's about the same as your old comp, a little over 3 hp. If you had enough with the old the Puma would work. It's a little light for a lot of sanding, a little you could do, a lot not.

 

[qmdv]

My compressor head is a Saylor Beall 703. When I got it it was mounted to a pretty small tank on wheels and had a 1.5 hp single phase motor 3450 rpm. The guy that had it was a framing contractor and he ran a couple of nail guns with it. I mounted it on a bigger tank with 3 HP three phase motor 1750 rpm so I doubled the pulley size on the motor to get the correct pump rpm

I found a used 80 gallon horizontal tank that is ASME for 100 bucks. I am thinking of making this up with a new motor because I think that this compressor head is way better than anything that is reasonably priced

https://www.saylor-beall.com/pumps/

 

[matt_i]

Sounds like a good plan. I'd stay on single phase as you can get max HP for the lowest cost. With capacitor and motor-based phase conversion you only get ~~2/3 of the rated HP. Utility or digitally synthesized 3rd phase is best.

 

[marinusdees]

Sounds like a good plan. I'd stay on single phase as you can get max HP for the lowest cost. With capacitor and motor-based phase conversion you only get ~~2/3 of the rated HP. Utility or digitally synthesized 3rd phase is best.

That's why typically air compressors don't like phase convertors. They struggle to start.

 

[qmdv]

My 703 is listed as going 510 RPM and the 705 going 845 RPM. I wonder if I could HP up and increase pulley size to get more CFM. Just a thought.

 

[nadogail]

Good Luck finding the perfect compressor for your needs. I settled on a 20 gallon Devilbis because it was the closest thing to my semi educated estimate of my needs for the dollars in my budget. It has served me more than 20 years.

 

[The Tool Tyrant]

My 703 is listed as going 510 RPM and the 705 going 845 RPM. I wonder if I could HP up and increase pulley size to get more CFM. Just a thought.

There is no reason that you shouldn't be able to. I just compared part #'s between the 703 vs. 705 and the only difference's are cylinder/ pistons / head.
Same 16.75" sheave, same crank. The only reason RPM would be stated lower for the 703 is lower motor HP.

Many years ago, in my framing days, I bought a 'Hill Bros.' compressor for work which used the 703 pump with a 3HP Baldor motor on a 12 gal. wheeled receiver. I actually still have it, and am planning on adding the pump and motor to a 80 vert. receiver that I pulled a Quincy QR-25-325 off of and giving it to my son.

IMHO, You'd be stupid not to do it...great pump.

 

[qmdv]

Many years ago, in my framing days, I bought a 'Hill Bros.' compressor for work which used the 703 pump with a 3HP Baldor motor on a 12 gal. wheeled receiver. I actually still have it, and am planning on adding the pump and motor to a 80 vert. receiver that I pulled a Quincy QR-25-325 off of and giving it to my son.

IMHO, You'd be stupid not to do it...great pump.

What rpm motor ran that 703 and what was the sheave size?

I sent an inquiry to Saylor Beall and heer is the reply:
Timothy,
Thank you for your inquiry. The max RPM on a 703 pump is 510 RPM and it can not go any faster due to valve float and efficiency.
thanks
Jeff Zampaloni
Regional Sales Manager
Saylor-Beall Manufacturing Company

Reply came from a sales manager not an engineer

 

[TractorJeff]

Chances are he his correct because it only takes a couple of seconds to get a reply from the Engineering team or he may have been an Engineer at one time.

 

[The Tool Tyrant]

What rpm motor ran that 703 and what was the sheave size?

I sent an inquiry to Saylor Beall and heer is the reply:
Timothy,
Thank you for your inquiry. The max RPM on a 703 pump is 510 RPM and it can not go any faster due to valve float and efficiency.
thanks
Jeff Zampaloni
Regional Sales Manager
Saylor-Beall Manufacturing Company

Reply came from a sales manager not an engineer

The motor is a 3HP 1725 RPM Baldor. I'll check the drive sheave for diameter.

I again checked my parts book and all three, 703, 705 and 707 use exactly the same part numbers for valves, only difference is that the 703 only has 1 low pressure intake valve rather than 2 as the 705 and 707 (actually 4 as it uses 2 cylinders).
The only reasoning I can think of for 'valve float' at a higher RPM would be the possibly of too much air volume trying to pass through 1 L.P. valve, so basically the volume of air would place a greater resistance on the valve spring than it could handle.

 

[qmdv]

The motor is a 3HP 1725 RPM Baldor. I'll check the drive sheave for diameter.

I again checked my parts book and all three, 703, 705 and 707 use exactly the same part numbers for valves, only difference is that the 703 only has 1 low pressure intake valve rather than 2 as the 705 and 707 (actually 4 as it uses 2 cylinders).
The only reasoning I can think of for 'valve float' would be the possibly of too much air volume trying to pass through 1 L.P. valve, so basically the volume of air would place a greater resistance on the valve spring than it could handle.

If I go for a 110 RPM increase That will add a third of the difference difference between the 703 and 705. Probably work just fine. No substitute for cubic inches

 

[The Tool Tyrant]

If I go for a 110 RPM increase That will add a third of the difference difference between the 703 and 705. Probably work just fine. No substitute for cubic inches

It will be interesting to find out how fast my 3HP was driving the 703. I'll check it tonight when I get home.
Another thing to consider since it sounds like you're buying a new receiver, would be to go with maybe a 120 gal to help give you more usable air between pump cycles...saves the motor too.

 

[BPJOOP93]

Where are you located?? I have a 3 phase 5 hp not in use. 30 gallon I think. It would be cheap

 

[Asahi1234]

I bought a Quincy 60 gallon MADE IN USA at Northern Tools. I have had it for 3 years. Where I work they bought 10 of 60 gallon Ingersoll Rand. They had nothing but issues with Ingersoll Rand. They have to replace 8 out of 10 compressor. They were working 12 to 16 hour days. They replace them with Quincy No problems with them. The Quincy have been running fine no problem with any of them. Still working same hours.And it's been 3 years. Buy USA better made and better quality.

 

[The Tool Tyrant]

If I go for a 110 RPM increase That will add a third of the difference difference between the 703 and 705. Probably work just fine. No substitute for cubic inches

I measured the drive sheave last night and it measured 7.15, that being said,
7.15 ÷ 16.75= .4268 x 1725 = 736 RPM.

Being as my 703 came this way from Hill Bros, whom used Saylor-Beall pumps on all of their compressors, I can't believe they didn't have S.B.'s blessing to set them up with this combination.
I used this compressor for many years without any issues whatsoever.

 

[NUTTSGT]

I believe there's a family in Denver that has a compressor they don't need. It was delivered unexpectedly.

 

[pancho400cid]

I believe there's a family in Denver that has a compressor they don't need. It was delivered unexpectedly.

Too soon!

https://www.garagejournal.com/forum/showthread.php?t=460702



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