Compair 175S compressor (cr175)

[Tazza]

I know this is a real long shot but never hurts to ask.
I went and bought an old compressor on Monday to power my home made sandblaster. The machine works really well but I don't have any information on it. I managed to get a generic maintenance schedule for mobile screw compressors but I'd like a little more info on things like changing the air pressure, checking the pump oil pressure etc. I have NO experience with screw compressors and I don't want to over look something and ruin it. I made sure I checked the engine oil level before it started it, but I still don't know how to check the pump oil level, what oil should be used etc. The information I got did say to drain the reserve tank daily, but I don't even know how to get to it to do that!!!
The thing that also amazes me is the reserve tank is TINY, maybe 1.5 - 2 times the size of a BBQ gas bottle!!! Even so, does this thing move some air!!! from the numbering I assume the 175 means 175 CFM. I hope to hook it up to my sandblaster on the weekend and see what it does.
Its kinda old, about 30 years but starts really well and blows no smoke.

 

[Gazza]

Hi Tazza, your timing is great. As I was reading this one of my clients rang to organise some stickers for tomorrow, guess where he works Compair!!! He works as a spray painter there and said that these were Australian built and are a very reliable compressor, they still service them so he will try and get some details for you. thanks Gazza

 

[Tazza]

Hi Tazza, your timing is great. As I was reading this one of my clients rang to organise some stickers for tomorrow, guess where he works Compair!!! He works as a spray painter there and said that these were Australian built and are a very reliable compressor, they still service them so he will try and get some details for you. thanks Gazza

Thanks for that!!
Thats perfect, if he works in service thats the info i wanted. Any information you can russle up would be great. I'll try and take a pic of it over the next few days, they predict rain for the next 4 or so days which is a bit of a pest, i want to test using it to power my sandblaster.
I'm actually amazed at how well it runs for a 30 year old machine, no smoke and heaps of power. It runs a Ford 4 cylinder direct injection diesel engine.

 

[skidsteer.ca]

Thanks for that!!
Thats perfect, if he works in service thats the info i wanted. Any information you can russle up would be great. I'll try and take a pic of it over the next few days, they predict rain for the next 4 or so days which is a bit of a pest, i want to test using it to power my sandblaster.
I'm actually amazed at how well it runs for a 30 year old machine, no smoke and heaps of power. It runs a Ford 4 cylinder direct injection diesel engine.

It should be 175 cfm with that kinda power.
The rain is coming from the low in the atmospheric pressure from you created starting that thing up!
Ken

 

[perry]

It should be 175 cfm with that kinda power.
The rain is coming from the low in the atmospheric pressure from you created starting that thing up!
Ken

A retired friend was a salesman and tech guy for an air compressor company, I ask him about screw compressors and he said I would need three phase to run it. From what I've seen and heard Tazza, your gonna enjoy that beast.

 

[mllud]

A retired friend was a salesman and tech guy for an air compressor company, I ask him about screw compressors and he said I would need three phase to run it. From what I've seen and heard Tazza, your gonna enjoy that beast.

I have a 90 cfm Ingersol rand screw compressor with a 2 cylinder duetz. There i a sight glass on a hohizontal tank. On mine the oil is about half way up the tank.
I use mine for personal use sandblasting. Screw compressors put out a lot of volume with little storage
Condension is a big problem.I pick my days to blast. I live in Missouri where the humidity is high I try to blast when its low.I thought about adding another air cooler. I did add a large water trap that helps. Sandblasting is a nasty job but there is no other way to get a better finish to paint
Mine was a portable unit on wheels. It got backed into by a cat and crushed the cabinet and trailer undercarrage. Low hours and never fails. Mike

 

[Tazza]

I have a 90 cfm Ingersol rand screw compressor with a 2 cylinder duetz. There i a sight glass on a hohizontal tank. On mine the oil is about half way up the tank.
I use mine for personal use sandblasting. Screw compressors put out a lot of volume with little storage
Condension is a big problem.I pick my days to blast. I live in Missouri where the humidity is high I try to blast when its low.I thought about adding another air cooler. I did add a large water trap that helps. Sandblasting is a nasty job but there is no other way to get a better finish to paint
Mine was a portable unit on wheels. It got backed into by a cat and crushed the cabinet and trailer undercarrage. Low hours and never fails. Mike

LOL Ken, i like that and you are probably rite
Perry - i can totally see where the need for 3 phase comes from, when i open an air outlet it automatically throttles up with a big roar! It does require a fair bit of power to move such a large amount of air.
Mllud - mine actually runs a hydraulic pump on the end of the compressor that is used to lubricate the pump and cool it, it has a large oil cooler as well to keep the oil cool. I can totally see water being an issue, i ran it on Wednesday which was fine, a little humidity and when i opened an air outlet you could see the water vapor. I was amazed at the storage tank, so tiny but it produces the air so quickly its really not needed, I'm just used to the piston type that take time to fill up.
As for backing over it, i have done the same.... I backed over a *postie bike* little Honda motorbike, i got out as i felt something and all i could see were a pair of handle bars sticking out.... it was a horrible sinking feeling! but it did survive!

 

[mllud]

LOL Ken, i like that and you are probably rite
Perry - i can totally see where the need for 3 phase comes from, when i open an air outlet it automatically throttles up with a big roar! It does require a fair bit of power to move such a large amount of air.
Mllud - mine actually runs a hydraulic pump on the end of the compressor that is used to lubricate the pump and cool it, it has a large oil cooler as well to keep the oil cool. I can totally see water being an issue, i ran it on Wednesday which was fine, a little humidity and when i opened an air outlet you could see the water vapor. I was amazed at the storage tank, so tiny but it produces the air so quickly its really not needed, I'm just used to the piston type that take time to fill up.
As for backing over it, i have done the same.... I backed over a *postie bike* little Honda motorbike, i got out as i felt something and all i could see were a pair of handle bars sticking out.... it was a horrible sinking feeling! but it did survive!

I was reaing a while back when everyone was talking sandblasters. Im no expert but have Quite a few hours running mine. When I had my 17cfn piston pump and was always starving for more air I ran 140 psi. After I got this screw compressor with a contant steady supply of air I ended up liking to run it at about 90psi.It will be a lot easier for you to fine tune the volume of air and sand mix with a steady air supply.
I understand the abrasive being used makes a lot of difference. My sand comes out of the Mississippi river. Its sifted dried and baged in 100lbs
One thing I didnt notice on your sand pot. Do you have air running to the top part of your tank? I have a 300lb commercial pot. Im not sure what they call the valve and air line going to the top . I call it a choke. It also helps adjust the sand flow when humidity is a problem.You can also use it to blow out a clog. Good luck with your new compressor. Mike

 

[Tazza]

I was reaing a while back when everyone was talking sandblasters. Im no expert but have Quite a few hours running mine. When I had my 17cfn piston pump and was always starving for more air I ran 140 psi. After I got this screw compressor with a contant steady supply of air I ended up liking to run it at about 90psi.It will be a lot easier for you to fine tune the volume of air and sand mix with a steady air supply.
I understand the abrasive being used makes a lot of difference. My sand comes out of the Mississippi river. Its sifted dried and baged in 100lbs
One thing I didnt notice on your sand pot. Do you have air running to the top part of your tank? I have a 300lb commercial pot. Im not sure what they call the valve and air line going to the top . I call it a choke. It also helps adjust the sand flow when humidity is a problem.You can also use it to blow out a clog. Good luck with your new compressor. Mike

Mllud - the main air supply does connect to the top of the pot too. There is a T piece at the top that in my main air supply in that goes to the pot and the final leg of the T piece runs down the back through a pope to the base where the ball valve is for adjusting sand flow. I will try and get a petter picture of the setup.
Currently the compressor is set to 80 PSI, the media i am using is ilminite (black sand) that won't kill me or anyone else with the dust it makes. I'd like to use beach sand as its so cheap i can use it once and forget about it.

 

[mllud]

Mllud - the main air supply does connect to the top of the pot too. There is a T piece at the top that in my main air supply in that goes to the pot and the final leg of the T piece runs down the back through a pope to the base where the ball valve is for adjusting sand flow. I will try and get a petter picture of the setup.
Currently the compressor is set to 80 PSI, the media i am using is ilminite (black sand) that won't kill me or anyone else with the dust it makes. I'd like to use beach sand as its so cheap i can use it once and forget about it.

Tazza: With that volume of air you could give it a try at 80psi. It may be all you need. Mike

 

[mllud]

Tazza: With that volume of air you could give it a try at 80psi. It may be all you need. Mike

I guess the statment above doesnt make sence. You cant get any more volume than the blasting tip allows. You should be able to go to a larger tip. Mike

 

[Tazza]

I guess the statment above doesnt make sence. You cant get any more volume than the blasting tip allows. You should be able to go to a larger tip. Mike

Exactly, i knew what you meant, don't worry
I was going to try about 1/4" and maybe work up a little more. I can hold 90PSI with a 1/8" nozzle with 2 compressors providing just under 30 CFM so i can't see why i can't go 1/4" or even 5/16" but this will take some fiddling to work out what works best. The nozzles i am using are home made and won't last, but i can build better ones when i work out what works best.

 

[Tazza]

Exactly, i knew what you meant, don't worry
I was going to try about 1/4" and maybe work up a little more. I can hold 90PSI with a 1/8" nozzle with 2 compressors providing just under 30 CFM so i can't see why i can't go 1/4" or even 5/16" but this will take some fiddling to work out what works best. The nozzles i am using are home made and won't last, but i can build better ones when i work out what works best.

Here is a piccie:

Above pic you can sort of see the screw compressor part, behind the battery. Its amazing something so small can produce so much air! i'll try for a better picture when i get a chance.
Better quality piccies:
http://users.tpg.com.au/tazza_/Comp/Image013.jpg
http://users.tpg.com.au/tazza_/Comp/Image014.jpg
http://users.tpg.com.au/tazza_/Comp/Image015.jpg

 

[skidsteer.ca]

Here is a piccie:



Above pic you can sort of see the screw compressor part, behind the battery. Its amazing something so small can produce so much air! i'll try for a better picture when i get a chance.
Better quality piccies:
http://users.tpg.com.au/tazza_/Comp/Image013.jpg
http://users.tpg.com.au/tazza_/Comp/Image014.jpg
http://users.tpg.com.au/tazza_/Comp/Image015.jpg

I would think even at low rpm you could run 5/16. Would be best to get it set so it does not cycle in and out too much??
Ken

 

[mllud]

I would think even at low rpm you could run 5/16. Would be best to get it set so it does not cycle in and out too much??
Ken

If Im following what Ken is saying on a screw compresor if you are only using a small portion of the air being put out the compresor will load and unload constantly. I usually let the air bleed off with a valve when Im shuting off the sand flow to move my project or adding sand to the pot.
If you have a lot of let excess air you may want to Install a valve to let some of that air bleed off. I think its easier on the compresor. This is what I have experienced with mine That doesnt mean yours will do that. Mike

 

[mllud]

If Im following what Ken is saying on a screw compresor if you are only using a small portion of the air being put out the compresor will load and unload constantly. I usually let the air bleed off with a valve when Im shuting off the sand flow to move my project or adding sand to the pot.
If you have a lot of let excess air you may want to Install a valve to let some of that air bleed off. I think its easier on the compresor. This is what I have experienced with mine That doesnt mean yours will do that. Mike

Tazza
My 90cfm compresor with a 1/4 inch orphis/tip maintains 90psi at full open.
Unless you increase the size of your blasting hose and tip drastically I think you will have a lot of excess air.
Im sure you will work it all out. Youcan do ome serious blasting with the air you have. Mike

 

[Tazza]

Tazza
My 90cfm compresor with a 1/4 inch orphis/tip maintains 90psi at full open.
Unless you increase the size of your blasting hose and tip drastically I think you will have a lot of excess air.
Im sure you will work it all out. Youcan do ome serious blasting with the air you have. Mike

I will need to fiddle i think.... I haven't played with the compressor much yet, just started it so i at least knew it ran!
As far as i can tell, this one is governed by the pressure of the tank, so if you require a little more air it throttles up just enough to provide that, its not like it goes full throttle then when its up to pressure it eases off. I'm really not sure but i can experiment. As mine is attached to an engine, the output is essentially variable unlike yours that is attached to a constant speed electric motor so *possibly* mine will only throttle up to the speed that is required to provide the needed air supply, but i will need to fiddle to confirm this.
I'm really itching to try it out..... This rotten weather!

 

[mllud]

I will need to fiddle i think.... I haven't played with the compressor much yet, just started it so i at least knew it ran!
As far as i can tell, this one is governed by the pressure of the tank, so if you require a little more air it throttles up just enough to provide that, its not like it goes full throttle then when its up to pressure it eases off. I'm really not sure but i can experiment. As mine is attached to an engine, the output is essentially variable unlike yours that is attached to a constant speed electric motor so *possibly* mine will only throttle up to the speed that is required to provide the needed air supply, but i will need to fiddle to confirm this.
I'm really itching to try it out..... This rotten weather!

Mine does run off of a 2 cyl. Duetz diesel. It does governe itself but seems to load down and unload a lot if im not using full air. It may need an adjustment. It a whole different world when you have plenty of air. Gets the job done. Mike

 

[mllud]

Mine does run off of a 2 cyl. Duetz diesel. It does governe itself but seems to load down and unload a lot if im not using full air. It may need an adjustment. It a whole different world when you have plenty of air. Gets the job done. Mike

Tazza
One thing my owners manual stresses. On start up it is important to have the main air valve closed. It has to do with the oil getting started circulating. May not be important on yours. Mike