|Forum topic by Whiskers||posted 03-21-2014 06:35 AM||1774 views||1 time favorited||36 replies|
03-21-2014 06:35 AM
Anyone familiar with my postings knows I’m setting up shop, and one of the things I have been working on heavily the last couple days was a good compressed air setup. I did lots of research in various forums, many of them garage etc and the universal consensus was the best materials for this is metal pipe. If your into painting cars, galvanized pipe may be best, otherwise ordinary black cast iron pipe is fine. The reason for the difference is that the black pipe is more conducive to rust, and rust to a car painter is like silicon is to woodworkers.
My design started simple, I wanted air available everywhere while keeping my compressor conveniently stowed away. In one corner of my garage I’m building a equipment closet that stows my compressor, dust collection setup, water heater, and has storage for lots of other stuff or future equipment. My super fancy HF $110 compressor will sit on a shelf over my hot water heater. Air outlet consisted of a HF reel which hangs from the ceiling and has 50’ of rubber hose. If you ever been in a professional garage you have probably seen similar things. All I needed to do was connect them. A light switch on the outside of the closet would turn on/off the power to a ordinary wall outlet to power the compressor on and off without having to run in and out of the closet. It got expanded a bit cause upstairs over the garage is my master bedroom, and I wanted a air outlet there near my desk cause I also like to make models, especially in winter when it cold, and do airbrush work. Since I don’t want to run up and down the stairs when I am playing I am putting in a 2 way switch with one upstairs and one on the outside of the closet.
Rule 1 which is universally accepted among most anyone is avoid any and all plastic type materials. It will invariably fail over time. Some people use these fancy expensive plex and other weird plastics but they are expensive, will eventually degrade and fail, catastrophically sometimes, and are usually very small in diameter restricting airflow. I’m not sure how significant it is, but if you got runs of 1/2” metal pipe it going to act just like the tank on your compressor expanding the stored air. Maybe one of you know it all mathematicians will pipe in and tell me how many gallons of air my 30’ or so of 1/2” diameter pipe has added to my total storage.
One problem with working with metal pipe of any kind is you have to pick one end and run to the other. If you ever have to break a piece apart you practically have to tear the entire line out. A thing called a union helps solve this problem as it can be tightened on both sides, but be prepared to work from end to end and get it right the first time as you go.
Rule two is be prepared to pressurize and test every couple pieces of pipe. Metal pipe is a pain in the ass to get a air tight seal. Now here is where some of my new found experience has come in. In the past I’ve always used teflon tape to seal air connections. It seemed to work better than pipe joint compounds and was much more convenient cause usually it seemed when I needed it the pipe joint compound would be dried up and useless. Well here the thing, for brass or chromed steel fittings the teflon tape is fantastic, the best material. It works, cleans out easily if you change fittings, and is always ready to go. But it sucks to seal pipe, it won’t work. The threads are too big and sharp. I’m just telling you this up front so you won’t waste your time with it. Small brass or chromed steel fitting, go with the tape, Pipe, you will have to use the pipe joint compound, and even than, test test test, cause metal pipe a pain.
Rule three, don’t be a gorilla, you do have to tighten things up good, but it doesn’t take a terrible amount of pressure. Besides, cast iron is a soft material, easily stripped.
Rule Four, when drilling holes thru wood for the pipe to run through, and you should, make pieces to support it etc, running thru floors especially this applies, go a little oversize. Don’t drill a hole just the perfect size for the pipe to slip thru. It a pain in the ass when dealing with large holes to widen them later, and with pipe it needs a little wiggle room to get it in position properly. A half degree off you can’t get the fittings and pipe to align. Go back later with some silicon caulk after the pipes are in to seal them into their holes to shut off bug or air traffic flows if that what your concerned about. If your working with 1/2 pipe it is 7/8” outer dimension. When Drilling thru a wall or floor, go a full inch when drilling the hole, you will be glad you did. For support pieces that you may make 15/16” is purrfect.
A few more notes, not rules. This stuff is nasty to work with, be prepared to become really dirty. Find some clothes you have written off and are ready to throw out and just wear them from start to finish on the job, and than toss them.
Black pipe can be painted, Surprise! :) but prepare first before putting it up. Great way to deal with any pipe, black or galvanized, is get a gallon of WD40 from tractor supply or somewhere for about $20. Wet paper towels or a sponge heavily with it and clean the exterior of the pipe. Galvanized pipe has a oil coating on it to help release it from the mold, and that oil is kind of hard to clean, Black pipe has something even more terrible and insidious, and really a pain to clean but the WD40 does a great job of removing it. After that you than have clean the WD40 off, which is still a oil, but a much easier to clean oil. Simple Green works great for this. Let it cook in the sun a bit to dry and prime, paint, enjoy.
If there is any interest in this thread I’ll come back later and post pictures to show methods of how to run the pipes them self, Especially for water drainage which is super important and how I did some of the supports etc. It late now though and I just got all that nasty black pipe gunk off me and not going back into the garage.
One more final piece of advice, when sourceing your materials, find a nice local ma and pa type hardware store for all the small stuff. Fittings, Nipples (short little pieces of pipe), etc. Buy extras and lots of them, you always seem to be off in measurements, have to make little jogs around unexpected obstacles, etc, and it better to have lots of stuff to work with when doing the project rather than waste time running back and forth to the store. With the small stores returns are easy. For the pipe itself, go with Lowe’s of HD, they are as cheap as anyone and will cut and thread it for you. Also it cheapest to buy a 10’ hunk and have it cut and threaded rather than buy the pieces they already cut for you. I don’t know why that is, it just is. They may say they can’t cut and thread less than 3’, but that not true, they can go down to a foot. Just need to find a smart boy who knows the machine.