Shop Time w/T.W. Friends

Been pricing 1/2" black iron pipe to do the air lines in my shop. I need roughly 100'

First metal supply place, $21.XX for 21' with a $30 delivery charge
Second metal place, $30.XX for 21' with a $30 delivery charge
3rd, hardware store 10 miles from home, $25.XX for 10'
4th, plumbing supply place not far from work, $21.XX for 21'

I have to drag my trailer to work anyway to pick it up so I may as well get it from the plumbing supply place. By the time I drive my truck, I can't drive to either of the metal supply places to save $30 delivery charge and make it worth while because they are so far away from home and work.

 

Did you check the price of conduit?

When I did mine, I used 3/4" rigid conduit. It's galvanized and it was $3/10' length cheaper than black iron.

 

I haven't checked on conduit, I'll see what they have to offer. I know Lowe's is super higher than any of them, just checked their prices and they only offer 10' stuff.

 

I just checked, too. The prices have gone up a lot in10 years.

 

A 2 stage compressor cuts off at 175 psi, nothing to take shortcuts with IMO.

I guess you can use it although it isn't pressure rated and doesn't have the built in safety factor of black iron.

Another potential problem is the galvanized coating on the inside flaking off over time and getting into tools, regulators & such.


Personally I would (and did) use US made black iron from a plumbing supply house.

The old "buy once, cry once" thing - really the larger cost of the job is the fittings not the pipe.

 

I've already got my fittings (most of them). Got them at the local hardware store, they were cheaper than McMaster Carr. I looked at Amazon but couldn't find in writing what I wanted. Most were for decorative purposes and not pressure so I finally went to the hardware and put hands on.

 

Made these yesterday and stuck them in the freezer before I left, they shrank .002" which is exactly what I needed for a drop in/snug fit.

303 stainless




Had to press one of them half way in so I left it in the press while they warmed up.





Thank goodness this ugly weld gets turned off. Just because you have a TIG welder, doesn't make you a TIG welder.

 

I bought all my fittings new and my golly did that add up!

On the other hand I did exactly what I wanted (overkill naturally ) and the system does exactly what I designed it to do - plenty of clean, dry air readily at hand.

The system will still be working fine decades after I'm gone.

 

It’s like you read my mind…

 

All good points.

Black iron pipe and galvanized rigid conduit are the same thing.

The only difference is the galvanization coating. I don't think the burst pressure is going to change that much.

The fittings are different, so use pipe fittings couplers, not conduit couplers.

If the pipe bursts from overpressurization, then you have 2 problems that needed fixed before the pipe burst.

The pressure cut off switch is defective and the tank over pressure relief is defective.

As for flaking off of the galvanization, I've never seen that happen, but I guess it could, but it's not an issue to me since almost all air tools have a screen on the air intake and the regulator is before the pipe system.

Enjoying the conversation.

 

Ok, some noob questions:

When designing a black pipe system for air, do you drill and use standard air fittings into the black pipe end caps?

Can you use teflon tape for joining connections?

How do you deal with moisture? Just angle to passively drain or do you use more active measures?

Any considerations for a system in an unheated garage where temps can get to 20-30 below?

Anything else to consider I didn’t ask about?

in advance.

 

200 tiny glow in the dark ducks to hide around work.

 

You can buy any kind of fitting to screw on the end of the pipe, no drilling in caps required.

I don't use teflon tape on black iron, I use thread joint compound. It comes in a can with a brush attached to the lid. It's a thick paste that doesn't get hard.

Moisture problems, drain the tank regularly if it has a drain on the bottom, you can also put a drip leg on the pipe with a 1/4 turn valve or at the end.

 

Thanks.

I’ve looked but can’t find screw on fittings for black pipe air. Would you have a link?

Thanks

 

You need a coupling with a reducing bushing down to 1/4".

 

You can get most fittings at local hardware stores or Lowe's.

Here's some of the crap we have at work

Some are capped off because we've moved machines.





Some is schedule 80 PVC

 

Looking like the print.

 

Ahh, gotcha! Thank you