Cutting threads on black pipe for compressor airline

[4rcFed]

I finally got the electrical done on my compressor and it is time to plan for the airline. From much of the reading on here, I might be going with black pipe. I just checked lowes today and it is not so bad in 10' lengths. But to make this custom fit to my shop, I will need to cut and splice.

What have you guys used to put threads on a piece of pipe after cutting it? I don't have any dies for that size of pipe and I was hoping that I can buy what I need, tool wise to do the job, fairly economically.

 

[gmwelder86]

I would suggest a rigid hand threader and tripod vise, as thats what I use are work but I am sure you can get a HF version that will do the job well enough. If you know what legnths you need cut lowes should be able to cut the thread the pipe there. When doing the basics like this their isnt much to, just fitting take offs and cut and screw together. and remember to tape and dope all your joints. and a couple pipe wrenchs, if its just 3/4 channel locks work fine but after awhile you will end up with pinched nerves in your hand. Ask me how I know that one :/

 

[pattenp]

If you're near a Harbor Freight store go buy one of the cheap manual pipe threaders. It will do for the one time use of threading what you need. Otherwise go to a rental place and rent one for a day.

 

[scott37300]

I have the same thoughts as you and have been planning on running black pipe for two years now. I also wanted to buy the tools I would need so I could just go pick the lengths of pipe up and cut them to whatever size I needed and not have to run to the box store to have them thread each and every cut of pipe. I ended up buying a nice ridgid cutter and also a ridgid pipe threader off ebay for pretty good price. The threader ended up having the dies shot even though it was described as "good condition". The dies are expensive so I ended up just buying another threader off ebay that had good dies. I haven't had time to put up any pipe in my garage but I did use it for some runs at work a few months ago and it worked great.

 

[volvo]

..
Thought I read in one of the last air line threads that , at Home Depot, if you bought a length of pipe they would cut and re-thread it for you at no charge?

11-28-2011, 10:58 PM #1 Plumbed in my air lines today (PVC-free thread)


http://www.garagejournal.com/forum/showthread.php?t=127130&highlight=black+pipe+air+line

>>>>I had the custom lengths cut and threaded at Home Depot. They didn't charge for the cuts or threading, you just have to pay for the length they cut it from.>>>>

 

[Provincial]

Watch the local Craigslist. Pipe tools come up often, and you will be able to check the condition before buying. Older tools seem to be higher quality.

I picked up a Rigid tripod vise for free with some other items I bought off Craigslist. I used a Harbor Freight threader set on my 1" black iron pipe. After about 10 joints it was noticably dull, and broke the casting that rachets after about 15 joints. It probably would have not broken on smaller pipe, or if the die hadn't become so dull.

A proper pipe vise will make the job much easier. I threaded about half the joints using a chinese bench vise that has pipe jaws. The Rigid chain vise works much better, with no slippage unlike the bench vise. For smaller pipe the Rigid-type vises that have a hinged top work very well.

Check out your commercial plumbing supplier for 21' lengths of black pipe. Much cheaper than the big box stores, and you can make full length runs with fewer joints, each of which is a potential leak point. They also can supply the fittings.

Plan you system so you can remove the valves without tearing out the whole system again. I have seen this happen in shops before. The installer did what was easiest and cheapest for him, and the owner paid the price later. Putting in a 'union' (which is a take-apart joint) allows you to break the pipe and allow unscrewing one side. Put them in strategic spots. Use bell reducers for smoother air flow into smaller outlets.

I am a beliver in big pipe. Air tool supply lines should be at least 1/2", main lines at least 3/4". I ran 1" because I have a 40x60 shop and am feeding two other buildings (a 30x36 and 38x75) that are 80 feet away. I ran the 1" in the rafters over the main shop and underground to a "T" feeding the other two. I put shutoff valves leaving the main shop and at the entrance to each other shop. The underground line is in 3" PVC pipe, with spacers to keep it off the bottom and open to daylight to drain any water that might inflitrate. I sloped it to daylight and have a sump and drain valve there.

 

[WhoWhatNow]

Home Depot will cut and thread for you if you buy the pipe there. Figure out how many/what size short pieces you need and have them do it.

 

[A_Pmech]

What have you guys used to put threads on a piece of pipe after cutting it?

I do all my pipe threading on the lathe:

 

[4rcFed]

Thanks for the input!

Provincial,

I assume that you were using something like this from Harbor Freight....just bigger:

HF Threader

And do you need to use a tripod vise, or just a regular vise mounted to a work bench?


Also, I was 'assuming' o using 1/2" black pipe. The garage is about 24'x40' (roughly). The compressor is in one corner, in the front. Most likely, I'll run the pipe up and then down between the two 16' ft garage doors. That will give me over 25' from the compressor to the main drop. From there, I might add another drop at the far end, or just run it back up and then to to overhead hose reels. Overall, not nearly the size of your shops.

 

[theoldwizard1]

I picked up a Rigid tripod vise for free with some other items I bought off Craigslist. I used a Harbor Freight threader set on my 1" black iron pipe. After about 10 joints it was noticably dull, and broke the casting that rachets after about 15 joints. It probably would have not broken on smaller pipe, or if the die hadn't become so dull.

Curious. Did HF replace it ? (Lifetime warranty on hand tools)


Never mind. Just read that there is only a 90 warranty on the threader.

 

[4rcFed]

I do all my pipe threading on the lathe.....

Nice!

The only thing close to a lathe that I have is an old ShopSmith.

 

[pro machine Engineering]

I would suggest going to your nearest oil field supply. I measure take the measurements to them they will cut the pipe thread it at no extra charge. And way cheaper than lowes or any other big box store

 

[MustangRick]

I cut and threaded mine with a HF threader. I don't know if I was not doing something right but the threads were not very good. I tried everything from different types of oil, threading 90 degrees and backing of 45 and 90 again, etc. I would always end up with a qtr inch or so of thread missing on a couple different places. As for holding the pipe, I had to borrow a vise that had pipe holding teeth in the jaws otherwise I could not hold it still.

 

[41ratrod]

If you just needing it for your air lines why not rent the cutter and vise.

 

[porcupine73]

I did my airlines in bip. I used the HF hand threader on a few areas. Every one of the ones I did with the HF threader leaked, especially the 2" lines. I did have a couple other leaks but those were easily fixed. I could not get any of the ones I threaded to stop leaking. Eventually I had to clean and sand around them, and apply JB Weld around them, that actually seemed to work!

 

[malibu101]

I do all my pipe threading on the lathe:
]

Wow! Nice!
It looks like it and I assume that is a tapered pipe thread you've made there, as is proper for this application.
Having the equipment, but especially the knowhow to set up and use the equipment to make something like that is something to be proud of.

 

[scott37300]

..
Thought I read in one of the last air line threads that , at Home Depot, if you bought a length of pipe they would cut and re-thread it for you at no charge?

11-28-2011, 10:58 PM #1 Plumbed in my air lines today (PVC-free thread)


http://www.garagejournal.com/forum/showthread.php?t=127130&highlight=black+pipe+air+line

>>>>I had the custom lengths cut and threaded at Home Depot. They didn't charge for the cuts or threading, you just have to pay for the length they cut it from.>>>>

Home Depot will cut and thread for you if you buy the pipe there. Figure out how many/what size short pieces you need and have them do it.

They will cut and thread all the pipe you want if you buy it from them. But it it SO much easier to just buy the pipe and go home and start cutting and threading as you go instead of trying to plan everything. One wrong measurement and you have to run back to the store. Not worth the time or effort when you can get good used tools for a decent price and be able to measure and cut and thread as you go at home.

I do all my pipe threading on the lathe:

Show off!!! I really really wish I could come across a good deal on a used lathe someday.

 

[sberry]

I see Menards had threading tools for sale on the shelf, didn't check the price.

 

[Shadowdog500]

I do all my pipe threading on the lathe:

Wow, how big is the through hole in your headstock?

I have a hand operated ratcheting pipe threader that my dad bought around 30 years ago from a mail order place like HF, but it was called something like Chicago pnumatic. It has worked fine every time I used it for small jobs. When I plumb the air lines this spring, I plan to borrow a friends rigid pipe threader.

Chris

 

[G_P]

Ridgid all the way.

I would use the HF threader if I was just making something out of pipe that did not need to be air/liquid tight. For compressed air you want quality tools that wont end up with you throwing away a bunch of pipe because of wrecked threads.

 

[Steevo]

I am a long way from mastering thread cutting on the lathe, much less tapered pipe threads.
Until then, free cutting and threading at HD works great for me. I bring my exact finished length, and they cut and thread for the price of the original pipe length. Leftover pieces go in my stockpile for future jobs. They will also put a thread on the end of your cut-off leftover length if you want them to.

 

[A_Pmech]

Wow! Nice!
It looks like it and I assume that is a tapered pipe thread you've made there, as is proper for this application.

Correct. NPT thread cut to the correct length of hand-tight engagement with a shop-made gage.

Wow, how big is the through hole in your headstock?

A shade over 2.5"


Whatever kind of threading equipment you end up using, it works a lot better with USA-made pipe! The Chinese stuff is horrible.

 

[4rcFed]

What pipe does HD carry - USA or other? If I just take advantage of the free cutting and threading, hopefully it is good pipe.

I love the idea for them to be able to do that, but I just know that I will screw up some dimension and end up going back. But I need to do some planning to get good measurements.

The guy who lived here before has a piece of galvanized up there with some elbows, which I assume used to go to a compressor, but to avoid any dis-similar metal interaction, I think I'll just replace that piece of galvanize and just use all black pipe.

 

[A_Pmech]

What pipe does HD carry - USA or other? If I just take advantage of the free cutting and threading, hopefully it is good pipe.

You'll have to go to a plumbing supply to get USA pipe and you may even need to specify USA at the plumbing supply. The big box stores usually carry the cheap Chinese stuff which tends to thread poorly, especially with hand threaders.

Most plumbing supply houses will also do threading, although they may charge a fee. You can also rent threading equipment from many hardware stores. If you go the rental route, make sure the threader has sharp inserts.

 

[Steevo]

All of the black pipe I bought at HD in November was made in Mexico. All of the fittings were from China. It's a regular international smorgasbord . . .

 

[rodm1]

On occasion HD gets in a stick or two of US or Canadian pipe but not very often. The pricing on pipe is extremely high compared to other suppliers of same quality pipe.

Look for a Ridgid r12 with the proper die head. You might be able to use a vice to hold the pipe from turning sometimes you can wrap a chain around it and use a pipe wrench to keep it from turning. You will be way happier if you just get the proper pipe vice.

 

[darkzero]

I do all my pipe threading on the lathe:

Very nice!

I wish I could have a taper attachment!

 

[larry_g]

I do all my pipe threading on the lathe:

I just can't resist....How's that work out for you at a remote jobsite?

Do ya just pack that lathe up in the truckbird?

lg
just funnin ya

 

[trainer]

I do all my pipe threading on the lathe:

Does this work with anything more than a few feet long?

 

[fireguy]

What pipe does HD carry - USA or other? If I just take advantage of the free cutting and threading, hopefully it is good pipe.

I love the idea for them to be able to do that, but I just know that I will screw up some dimension and end up going back. But I need to do some planning to get good measurements.

The guy who lived here before has a piece of galvanized up there with some elbows, which I assume used to go to a compressor, but to avoid any dis-similar metal interaction, I think I'll just replace that piece of galvanize and just use all black pipe.

There is no problem using a combination of black and galvanized pipe.

When you measure the space for your pipe, remember the length of pipe you will lose is 7/16 per each threaded end. That is known as take-out. You can use 2 hole clamps, or 1 hole clamps to secure the pipe. I like to use uni-strut and the clamps to secure pipe to walls. It looks more professional, and is more secure, but takes longer and costs more.

If you have home crapo cut and thread, check all threads with a connector. The threads should feel smooth when the connector is threaded on. Measure the length of the threads on a ******, and then measure the cut threads on the pipe. Too long or too short of threads make is difficult to assemble a leak-free connection.

Northern tool has a kit that is about $100.00, includes tubing and some ends. No need to cut and thread.

 

[justafurnaceman]

+1 for Rigid tools. That's all that we used when I was installing black iron pipes for heating systems.

You might be able to find some help with your project if you hook up with the HVAC guys in your area. We use to cut and thread pieces for people for a couple of bucks. One of the local larger hardware stores (NOT HD or Lowes) had a threader and they would only charge a couple of bucks too for a thread.

 

[A_Pmech]

Very nice!

I wish I could have a taper attachment!

Couldn't work a week without it!

Do ya just pack that lathe up in the truckbird?

Ya, it fits in the trunk.

Does this work with anything more than a few feet long?

Yes, I've threaded full sticks before. A V-stand is all that is needed, along with an appropriate speed low enough to prevent whipping.

 

[kngelv]

I'm a Journeyman Electrician and work primarily in industrial applications. I have threaded thousands of pipes. Mostly conduit but also other types. Stay as FAR away as possible from that HF threader. I used one once at a friends house, (should have brought my Rigid) the dies are not hardened properly and as others have stated you might have leakage issues. Rent a Rigid or take extremely accurate measurements and do all of them for free at Depot.

James

 

[danski0224]

I finally got the electrical done on my compressor and it is time to plan for the airline. From much of the reading on here, I might be going with black pipe. I just checked lowes today and it is not so bad in 10' lengths. But to make this custom fit to my shop, I will need to cut and splice.

What have you guys used to put threads on a piece of pipe after cutting it? I don't have any dies for that size of pipe and I was hoping that I can buy what I need, tool wise to do the job, fairly economically.

Buying good threading tools, even used, may not be worthwhile if you do not work with threaded pipe otherwise.

A RIDGID tripod vise, OOR ratchet, 1/2 and 3/4 OOR die heads, cutter and reamer is a big purchase. A recip saw or bandsaw *could* be substituted for the cutter and reamer, but the saw makes metal filings. This equipment, used, in good condition, could easily be ~$400.00. It is ~1000.00 buying all new.

I tried the HF small electric threader. It is junk. So are the HF dies. Waste of money. I gave it away, and that person tossed it.

Used RIDGID is 110x better than new HF.

DO NOT BUY HF PIPE THREADING STUFF. IT IS JUNK.

I can recommend the Rothenberger Supertronic 1250 if you want to buy an electric threader.

Home Depot cutting and threading is not necessarily free. They can charge the customer per cut, but many employees do not. It depends on the attitude of the customer.

What others have said about Chinese vs USA black pipe and fittings is true. I find that the China pipe threads fine by hand, but not so good with a machine. The OD of Chinese pipe is not consistent, and I have had problems getting dies started on Chinese pipe.

Unfortunately, finding US made black pipe is almost impossible at a box store. Finding US made black pipe fittings is harder. Even at a supply house, you need to specify USA materials.

 

[bobadame]

I used a Ridgid pipe threader on Mexican made 1/2" pipe. Worked just fine. I did have leaks though through some new Chinese fittings that I bought from HD. I dug through my bucket of used fittings and replaced the new leakers with some fittings that were at least 30 years old. The old used ones didn't leak. I had to cut into the line and install a couple of unions to fix the leaks. No more Homer Depot fittings for me.

 

[35mastr]

I have and use a Ridgid hand threader also. Also works great if there is ever a problem with any pipes in the house. Best 180.00 I ever spent.

 

[saabman]

Rigid pipe threader is the way to go. I have done 3 garages in black pipe over my lifetime and the manual threader works like a champ. Buy a kit with 1/2, 3/4, and 1 dies and you will be set.

I am getting ready to run pipe in my basement to support the machine shop I am creating. May use galvinized there.

I do have a HF pipe cutter and it works ok.

 

[Chris Adams]

I went with copper, so didn't need to thread.
However, while I was picking up some 2 inch black pipe for another project I noticed the local 'pipe and tank supply' did threading on any pipe.

You could bring in any pipe, they will thread it.
.75 or seventy five cents a thread.
Seemed reasonable.

They also sold the pipe at competitive rates.

Our local steel supplier sells bulk pipe, but does not thread. They do cut either free or cheap, depending on amount of cuts.

Lowes offered 'free threading' but only on pipe you bought then and there.
So you could go to Lowes, get most the stuff done free, then if you had a dozen or so leftover bits you wanted to fix or change, take them to a pipe supply.

I still went with copper, light, easy to bend, easy to lift into the attic, cheap and easy to solder.

 

[4rcFed]

Ok, what am I missing?

Lowes 1/2" black pipe 10'L - $10.62
Lowes Pipe

Lowes 1/2" black pipe 10'L - $22.08
Lowes Pipe

They are listed with the same dimensions but one is double the cost.

And I did check a local plumbing supplier and they do have pieces that are 21' in length, but those pieces are about $38 each.

 

[slip knot]

I ran 3/4 BIP for my air lines. Borrowed a threader from work but the cutter had screwed up wheels and I didn't want to pay to replace them so I used my chopsaw to cut the pipe. Some quick work with chainsaw file cleaned up the burrs and it threaded fine. Never used a pipe cutter since.

The plumbing supply house I use suggested that I tape and dope the threads on the fittings for a leak proof seal and I had no problems with leaks at all.