Compressor Build, never done this before

[GarageGuy89]

So after much frustration of the proud owner of a small dinky 30 gallon HD air compressor, I have been looking into a real compressor for high cfm tools.

At first glance my most demanding tool would be the blast cabinet. So, I started looking for something in the range of having a minimum of 20 cfm, only to find that the price of these would put me in the dog house for the next 20 years. Thus, as many of you know...when price exceeds your needs its time to bring out those innermost MacGyver skills.

So, when connecting a gas motor, compressor, and tank all together what is the methodology of everything for the air line? By that I mean what are the components needed between the air coming out of the pump and into the tank?

 

[md21722]

You need to size the gas engine correctly. They have a different power curve than electric motors, so you'd probably be using an 11 HP? You need to start with a pump that has head unloaders. And then you have to connect from from tank to pilot valve which in turns connects to the head to load and unload the valves. A check valve at the tank. There ain't too much to it.

 

[GarageGuy89]

You need to size the gas engine correctly. They have a different power curve than electric motors, so you'd probably be using an 11 HP? You need to start with a pump that has head unloaders. And then you have to connect from from tank to pilot valve which in turns connects to the head to load and unload the valves. A check valve at the tank. There ain't too much to it.

Roger that. So does the pilot valve open up if you hit max psi and your pump is open to atmosphere until you start using air again?

I guess I can't seem to wrap my mind around why a 5 hp electric motor is different then a 5 hp gas engine if your running them both at 3600 rpms or what ever rpms they are rated for???

 

[md21722]

Pilot valves have an adjustable cut in and cut out same as electric pressure switches. You will also need to investigate the throttle control for the gas engine. But here's an example, this IR compressor pump (24 CFM) would normally be paired with a 7.5 HP electric motor but here they are using a 13 HP Honda. https://www.zoro.com/ingersoll-rand...gclid=CL_I4MTl7s0CFQYuaQod67QJWw&gclsrc=aw.ds

 

[GarageGuy89]

Well there goes my cheap compressor...

I have an old 15hp vertical shaft engine lying around. Is there a possibility of hooking that up to the compressor with a quarter turn twist in the belt? I've seen it done on tractor pto's...

 

[md21722]

You're out of my comfort zone now. I have had tractors with PTO driven machinery but am not familiar with what you're talking about.

I think you're best bet is to search your local craigslist (your location is not posted otherwise I'd look and give you some suggestions) for some deals. Otherwise plan on paying for a new one. For blasting most people seem to say there happy by the time they get to 7.5 HP, though you can never have enough air. At least you're not in Colorado. With the high altitude, we have to oversize everything that uses air.

 

[GarageGuy89]

Seattle, WA

Basically what I am talking about is an engine with a vertical shaft going straight down. So the pulley on the engine would be parallel with the ground. The pulley on the compressor is perpendicular to the ground, thus you have a twist in the belt.

I used to have an old tractor who's engine shaft came out the front by the head lights, then went down and under to the mid section where the blades were.

 

[md21722]

Oh that would be really nonconventional for a modern day compressor.

This is a R30 Champion compressor you can run at 5 - 7.5 - 10 HP with a motor off eBay. You can get a 5 HP Baldor for around $329. They cost a kings ransom new http://seattle.craigslist.org/tac/tls/5680078077.html.

That's the type of thing I'd say you ought to be looking at to save some bucks.

But if you have problems, it can grow and keep being an issue, so sometimes its "cheaper" to take your wife out for some nice dinners and not talk about the new one you bought.

I am partial to Champion, Saylor Beall, and Jenny (Emglo). The nice thing with the Champions is that there is no cylinder head to blow and you can service the valves with a 9/16" wrench (no special tools). The head is aluminum with steel liners but its all one piece.. been making them that way for the past 60-80 years.

 

[GarageGuy89]

Oh that would be really nonconventional for a modern day compressor.

This is a R30 Champion compressor you can run at 5 - 7.5 - 10 HP with a motor off eBay. You can get a 5 HP Baldor for around $329. They cost a kings ransom new http://seattle.craigslist.org/tac/tls/5680078077.html.

That's the type of thing I'd say you ought to be looking at to save some bucks.

But if you have problems, it can grow and keep being an issue, so sometimes its "cheaper" to take your wife out for some nice dinners and not talk about the new one you bought.

I am partial to Champion, Saylor Beall, and Jenny (Emglo). The nice thing with the Champions is that there is no cylinder head to blow and you can service the valves with a 9/16" wrench (no special tools). The head is aluminum with steel liners but its all one piece.. been making them that way for the past 60-80 years.

Sounds like you know your compressors. Good stuff man. Thanks, I'll be doing some more research here.

 

[gearhead1]

The air goes into the tank on mine what appears to be a copper line, it has a pilot operated valve to release the pressure for starting or when the tank has achieved max pressure. Buy one of those valves and you're set.

As far as the belt goes, I know what you're talking about, I'd try it. I'd love to know how well it works. One one hand you could say there's a lot less torque on a lawnmower. On the other hand you could say that the mower could see a lot of torque when the grass is high. The engine will stall in high grass if you go too fast. Perhaps it reduces the life of the belt some. I say it's worth a shot.

 

[md21722]

And this is the kind of stuff I'd stay away from

http://seattle.craigslist.org/see/tls/5663244403.html

Folks with Speedaire's seem to thing they are made of gold. Speedaire is just Grainger's house brand, sometimes a Campbell Hausfeld, sometimes a Champion pump but they are almost never worth what they are asking for used.

 

[md21722]

And here's one that looks to be about 60 years old!

http://seattle.craigslist.org/sno/tls/5678273623.html

It looks like an obsolete Champion RE-7 or RE-10. I have an RE-7. They were last made in 1957!

But they won't put out the air you need...

This is a Champion R15 pump from the 1970s with a gas engine...

http://seattle.craigslist.org/tac/for/5638584269.html

About 17 CFM... if it works, it ain't a horrible price but you could probably get one for $500-800 if you were choosy and patient.

This looks like an another antique Champion single stage!

http://seattle.craigslist.org/tac/for/5644961733.html

Don't buy it but ya'll have some great stuff out there in Craigslist!

This looks like a Champion 5 HP but I'm not sure if its the Centurion or the Advantage series. The Advantage series has better pumps. Would need to see another picture. But the price is not too bad:

http://seattle.craigslist.org/skc/for/5672319413.html

 

[GarageGuy89]

Trying to figure out what the difference is between all the Champion R30, R30A, R30B, R30C, R30D?

Can only seem to find data on the R30D pumps and it's saying a minimum of 7.5 HP motor....

Anyone got a link or pdf of an older R30 pump, or know the difference?

 

[On-Wheel]

I have a pump with a relief valve/water drain canister,a tank with a one way valve.I use a hose to fill tank.The pump is under a table and tank is on wheels.

 

[PSYKO_Inc]

Wow, Seattle has all the good stuff. I've been coming up empty in Norcal lately. Had a shot at what looked like a Champion R30 a couple weeks ago, but I passed since I didn't think I'd be able to find a single phase motor powerful enough for it. Now I've got a line on a 7.5 hp motor and the ad for the pump has expired....

 

[md21722]

You'll probably need to get the serial number and then call Champion. On the R15's the main differences have been the valves, air filter style, shape of head fins, and addition of safety blow off on the discharge to the tank. I'd imagine similar changes with the R30's but am not sure.

Champion probably hasn't listed the R30 pump for 5 HP but it does list its minimum speed at 400 RPM. Turning the pump just over 400 RPM you should get about 19 CFM with a 5 HP motor. This wouldn't be a common configuration. Saylor Beall offers their 707 pump this way but told me they only sell a couple a year, usually to a municipality. Most folks wouldn't do it because it would cost $1,000 more than their 705 pump.

I'd run it at 7.5 HP (or even 10 HP) if you have good power available! I would only do the 5 HP if you were trying to keep cost at a bare minimum...