This is very true. Plus the extra wall thickness of the pipe does not help disapate the heat very well. Use 3/4 copper, preferably type L although it is more expensive but it easily exceeds the 120 lbs you will be running and the thin wall disapates the heat very quickly. Run it high on the ceiling and slope it back to a drop leg with a drain. We install this system quite often in new construction and old shop reno's. Using the condensor from an old car also works great.

 

I've never used copper tube before. I'll need a number of threaded inserts for drain valves, air in and air out, how do I mount these in thin wall tube? If I have to pay to get it made the price will go up very quickly, I live in a small rural town. Such a shame stainless is a poor heat conductor, I could get it made for free or very close to free.

 

Stainless would work I think. As for copper use pressure fittings that slide on and seal when tightened down. Good for as much as the copper line would hold. I used all flare fittings on my manifold through out the shop. I had no problem finding fittings to plumb in the quick disconnects and air and drain valves. both at Napa and the hardware store. Was quick and easy with a flaring tool set. Than I had 12 and 20 foot hose to connect to tools and the manifold. Wish I had my my shop back and the Ex's boy friend had a****.

 

No problem, you sweat these fittings on. Just have to be sure to use a backing wrench when tightening.

 

Ross is right on. That is the best way. Hard as I have tried I just never could get that way to work for me. When plumbing the house I would fix one leak only to have made two more. I gave up and went to plastic water pipe and or flair the copper.

 

Ok, looks like I'm going to learn a new skill.

 

I should have mentioned, you can also use a sweated-on union, most practical for say an inline filter that you might need to replace.

 

L type copper was mentiond earlier, does this refer to drawn tube rather than the coiled annealed tube? Is ordinary lead free silver solder ok or should I go up to an antimony solder?

 

Soldering is very easy once you learn the tricks. It is easy peasy and goes fast. Type L is hard drawn and you will need 90* ells, tees and pipe adapters as well as swet valves to complete your system. The trick to a successful soldered joint is cleanliness. It has to be perfectly clean. You need to wire brush both inside the fitting and the outside of the pipe, then using some Emory paper sand these areas till bright copper. Now do not touch them with your fingers. Fingerprints will cause a leak. Apply some paste flux to both half's of the joint
Assemble the fitting onto the pipe with a twisting motion. Two things to remember, heat rises and the solder will flow towards the hottest part of the joint.

You will also need a wet rag. Now say you want to swet an ell onto the pipe and the pipe is horizontal. Apply your heat to the outside of the elbow bend and touch your solder to the pipe just where it goes into the ell. Don't get your torch too close to the ell or you will overheat the works.

Move the flame around while holding your solder against the fitting. When the tube is the right temp the solder will melt and travel toward the hotter part which should be the inside of the ell. Remove the heat and work your solder around the joint. If it stops melting apply some more heat to the ell. When you get a good fillet all around the joint remove the heat and quickly wipe the joint with your wet rag to remove any excess. This is purely for cosmetic reasons. Not really necessary.

You can dunk the joint into a bucket of water to cool it. Now look closely inside of the open end of the ell to see if the solder swetted all the way in. It should have.

Now if you are going to swet a valve in you will have to disassemble the valve so the heat does not destroy the internals.

Practice on a few fittings. You will be surprised at how easy it is. Another point, copper is very soft. Treat it gently. Don't throw it around like steel pipe. You will cave in the ends then you on't be able to insert it into the fitting cause it is not round.

Good luck. You could probably get more info if you google " soldered copper pipe"

Steve

 

When plumbing your distribution system, typically the main supply piping is larger diameter, typically 3/4" in a small shop and run up and near the top of the wall. The main supply should be kept as short as possible with minimal bends, pitched AWAY from the compressor 1/4"/ ft of run. The end of the supply should be an elbow and vertical line to near floor level with a ball type drain valve. This leg should NOT be used as a supply drop, it is only for collection and draining. Drops can be 1/2" but should be done to minimize any moisture issues by routing them properly. The Ts in the supply line for the drops should point UP not down, Then two short nipples and two elbows are used so the drop comes off the supply T, goes up and then down in a 180 degree hump. The drop should come down the wall to a T with a quick connect pointing horizontal off the T. The drop should continue from the T with a vertical 12" long drip leg nipple with a drain valve at the bottom.

 

This shows a very practical layout.

One of the problems with drip legs with a drain valve is that "draining" accumulated oil and water with 90 psi in the system really amounts to "spraying" it all over. If you use 2 valves, one a foot above the bottom one, then you can shut off the upper one, open the bottom one, and minimize the pressure blowing the gunk out.

 

Or you could simply turn the compreesor feed off, and connect something like a blow gun and drain the pressure off the line before opening the drip legs. Or else add a fitting below the valve in the drip leg so you can attach a length of hose and run the end outside when draining.

One additional suggestion is when oiling air tools, add the oil directly into the fitting on the tool itself, never use an automatic oiler if using the same air supply for spraying. Use only as much piping and air hose as needed, excessive amount of hose (especially with a lot of bends in it, always lay out your flex hose as straight as possible, never leave it coiled up or use a hose reel or a "curly hose") will severely reduce the volume and pressure available at the gun.

 

I took the thick 3/4" or 1" copper water pipe and ran 4 pieces vertical with drains on the bottom loops. There is rarely any water that gets to the first actual service drop and I have blown probably 500 lbs through the sandblaster connected to the third drop and had only a few drops of water. That is with the 5 hp high volume compressor running almost continually.

 

This helped me quite a bit, a truck air dryer, they spit evey time its satisfied
although I had to pipe in a truck governor to make it work then 3/8 tubing
through the wall to outside. Me too with it always running and its a big one
Check out Keith Fenner (turn wright machine) "kef 791" on utube for the
one he made for a plasma cam.

 

I built a system exactly like this after I changed my well point! I used the old well piping and bought a few more fittings to make a "vertical racetrack" for the air to pass though with drains at the bottom...This works very well in my garage...Even the Harbor Freight sandblaster worked a lot better!