1st Time Compressor Buyer, NEED HELP!!!!

[Tom R.]

Re: 1st Time Compressor Buyer, NEED HELP!!!!

I took a long time to set up my lines and drops. PVC is the easiest and it can hurt you, as Gary said. You should never use it. My lines are Type L copper, with silver solder. It will withstand far more than the 135 psi my compressor puts out. You can use cast iron, but you need to thread it, it's very heavy, and it can rust inside. Aluminum lines are OK but it's sold in a kit with fittings that are plastic with an o-ring and I'm skeptical about their longevity. The kits are also expensive. Finally there is PEX and other cross-linked plastics. I don't know a lot about using this in an air line, but you have to have a special tool for the fittings (like cast iron) and you can't run a straight line with it.

Eastwood offers kits with that high-tech plastic (PEX?) they call "HDPE (High Density Polyethylene) wrapped around an aluminum core for the ultimate in durability and flexibility." I'm in process of upgrading my line system so looking at various options...good discussion here! As much humidity that I have got to deal with here along the coast, I'm apprehensive about the cast iron option.

http://www.eastwood.com/3-4-inch-professsional-compressed-air-line-kit.html

[Gary C.]

Re: 1st Time Compressor Buyer, NEED HELP!!!!

Tom, that's the same as the RapidAir kit, which is $30 cheaper. Several of my Texas Chapter friends have used this kit. Works great, easy to install. IIRC the fittings are compression. Gary....
http://www.autobodytoolmart.com/rapi...0-p-18860.aspx

[Dick W.]

Re: 1st Time Compressor Buyer, NEED HELP!!!!

Eastwood offers kits with that high-tech plastic (PEX?) they call "HDPE (High Density Polyethylene) wrapped around an aluminum core for the ultimate in durability and flexibility." I'm in process of upgrading my line system so looking at various options...good discussion here! As much humidity that I have got to deal with here along the coast, I'm apprehensive about the cast iron option.

http://www.eastwood.com/3-4-inch-pro...-line-kit.html

Tom, black iron schedule 40 pipe will last way longer than you will I know of air piping systems that are well over 50 years old, a few over 75 years old, with schedule 40. I like the Rapidair system, I did a small addition to my plumbing in the shop and used it.

The mistake most make is undersizing the pipe. I know my shop is larger that most, but I used pneumatic sizing charts to figure my system. At the furthest point from the compressor I wanted to be able to run a 1/2" air wrench (22 cfm) at the furthest point from the compressor. My main line from the compressor starts at 1 1/4", runs about 40' to 1" pipe with all the drops 3/4". The main line at the ceiling has a slight slope that drains back to the compressor, the tee lines slope slightly to the drops on the wall. The drops on the wall all have 1/4 turn ball valves to drain the moisture.

In a former life I was fleet maintenance manager for a private carrier. After being involved in building and equipping shops in five states, you quickly find mistakes that architects and engineers make. For instance using way too small a pipe size when you are trying to run a 1" impact wrench 100' from the compressor.

[Patrick N.]

Re: 1st Time Compressor Buyer, NEED HELP!!!!

Bob, over the years I have developed many compressors for Stanley / Bostitch and can add some thoughts. As Paul said in post #2, CFM and PSI are the key purchasing criteria if you ask me. A basic rule of thumb is get a compressor with 1.25 - 1.5 X's the CFM of your highest rated tool or tools at the required PSI. Stationary two stage is a great way to go. The next criteria would be size of tank, the larger the tank the more CF of air available to feed CFM. This way your compressor does not work that hard. I personally don't pay too much attention to HP. Back in the day most HP ratings were recorded as Peak HP just prior to failure. The HP game was not really a true measure of performance.

It also seems that the quality of Air Pump is a direct influence on long term reliability. We spent a good deal of time finding an air pump supplier and we ended us with ABAC in Italy- some of the best pumps out there and they are typically a go-to source for many suppliers.

The only other thing I'd add is if you get a type that is belt driven, and the belt needs replacing, be careful not to change the factory alignment between the pump and motor- these are actually carefully set to eliminate vibration. When we did inspections on failed compressors, vibration caused by misaligned parts was a common root cause. Once vibration is present it can destroy a variety of components and it does.
Good luck

[Paul J.]

Re: 1st Time Compressor Buyer, NEED HELP!!!!

Paul, Is that 3/4" copper pipe that you used? Very nice system.

Thanks Roger. It's all 1/2". I was going to use 3/4" to the first drops but when I did the calculations, I didn't need it. It's been a while, but as I recall you can get around 40 cfm through a half inch pipe at 100 psi. My compressor is rated at 18.1 cfm at 90 psi (135 psi max). Pressure loss over a 100 foot run is around 5 psi, and my longest runs are less than 50'. I feel that my design is sufficient and it has worked very well for me. I've done blasting and partially painted cars with this arrangement, and I'm confident that it will work fine on a full paint job.

Paul

[Tom R.]

Re: 1st Time Compressor Buyer, NEED HELP!!!!

Tom, that's the same as the RapidAir kit, which is $30 cheaper. Several of my Texas Chapter friends have used this kit. Works great, easy to install. IIRC the fittings are compression. Gary....

I see they also carry the straight-line kit. I take it the tubes are aluminum with that nice blue color. Anyone use this in conjunction with the flex tube? Any sense whether the cost is in-line with copper shown by Paul above?

http://www.autobodytoolmart.com/rapidair-fastpipe-modular-compressed-air-piping-kit-100-ft-p-22521.aspx

[Paul J.]

Re: 1st Time Compressor Buyer, NEED HELP!!!!

I see they also carry the straight-line kit. I take it the tubes are aluminum with that nice blue color. Anyone use this in conjunction with the flex tube? Any sense whether the cost is in-line with copper shown by Paul above?

http://www.autobodytoolmart.com/rapi...t-p-22521.aspx

That's a nice kit but it has some of the compression fittings that I just don't trust. This type of fitting has the inner compression sleeve that was designed for modern water supply plumbing applications. I don't remember the pressure rating, but its somewhere between 100 and 200 psi. The fitting itself doesn't fail, it fails by slipping off. However, I'm sure that they have some provision for it to stay on at least to around 120 or 140 psi, which would be enough.

Now that I dissed this system, I've seen it used in NASCAR shops, so it must work OK. One of the shops which I saw it in was vacant, and the distance of the lines was long. I did not have access to the compressor room, but it had to have been a large compressor.

As for the price of copper, I bought all of my lines before the price increase several years ago. I know that it is no longer the cheapest option.

Paul

[Dick W.]

Re: 1st Time Compressor Buyer, NEED HELP!!!!

That's a nice kit but it has some of the compression fittings that I just don't trust. This type of fitting has the inner compression sleeve that was designed for modern water supply plumbing applications. I don't remember the pressure rating, but its somewhere between 100 and 200 psi. The fitting itself doesn't fail, it fails by slipping off. However, I'm sure that they have some provision for it to stay on at least to around 120 or 140 psi, which would be enough.

Now that I dissed this system, I've seen it used in NASCAR shops, so it must work OK. One of the shops which I saw it in was vacant, and the distance of the lines was long. I did not have access to the compressor room, but it had to have been a large compressor.

As for the price of copper, I bought all of my lines before the price increase several years ago. I know that it is no longer the cheapest option.

Paul

All the newer shops in the Charlotte area have the flex tube setup. Patton's in Charlotte is the #1 supplier of compressors and air handling systems to the teams