ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
UL 508A SPACING
by ale348 - 03/29/24 01:09 AM
Increasing demand factors in residential
by tortuga - 03/28/24 05:57 PM
Portable generator question
by Steve Miller - 03/19/24 08:50 PM
Do we need grounding?
by NORCAL - 03/19/24 05:11 PM
240V only in a home and NEC?
by dsk - 03/19/24 06:33 AM
New in the Gallery:
This is a new one
This is a new one
by timmp, September 24
Few pics I found
Few pics I found
by timmp, August 15
Who's Online Now
1 members (ale348), 302 guests, and 14 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 1 of 2 1 2
#195413 08/01/10 01:23 PM
Joined: Jan 2004
Posts: 171
M
Merlin Offline OP
Member
Ok...so I need some help. Although I am not new to the industry, I have never tried to cut threads in aluminum pipe. I am wiring a new grain bin and using aluminum pipe. It is great to work with.....well it was until I had to cut and thread it.

Can anyone one give me any pointers on how to thread this stuff? What do I need to use for a threading compound? I can cut the threads ok but when I go to back off the die, the cuttings get bound up in the threads and destroy what I just cut. Help....please!

Thanks, Merlin

Joined: Jan 2005
Posts: 5,445
Likes: 2
Cat Servant
Member
Sure .... prepare to forget everything you think you know about pipe!

First off, aluminum is considerably softer, weaker, and -paradoxically - a lot less forgiving than steel. You'll have to take considerable care not to crush or fltten it in your vise, when bending it ... and you can forget about 'unbending' it if you make a goof.

Wear gloves - the oils in your hands will oxidize the aluminum, and turn your skin black.

As for cutting threads, go to a machine shop supply house, or visit one online, like MSC Direct. You'll want to use a water-based cutting fluid - I reccomend LPS Green - rather than the usual threading oils.

Once you thread something tight in aluminum, you can forget about loosening it; you'll usually destroy the threads. It's probably a real good idea to use Noalox on the fittings for this reason.

Joined: Jan 2004
Posts: 171
M
Merlin Offline OP
Member
Thanks, Reno. So can I use regular pipe threading dies or do I need special dies?

Joined: Jan 2005
Posts: 5,445
Likes: 2
Cat Servant
Member
Regular dies are just fine .... just pay attention to the chips, and back the dies off several times to break the chips. Be wary of the chips as well, as they will iterally be razor sharp.

Joined: Jan 2004
Posts: 171
M
Merlin Offline OP
Member
Thanks for your help. I tried a different set of dies and they worked much better. I must of had a dull die that was causing me some aggravation. I actually used WD-40 for lube and it worked great. Thanks again for the info.

Joined: Mar 2005
Posts: 1,803
Member
The problem with cutting near pure aluminum is that it's so soft. You need an acute rake angle on cutting tools to get them to penetrate properly, and a standard die set will usually be set up for steel. That usually means they cut oversize first pass. Reno's answer of a cutting 'gunk' plus cycling the die down is the solution. Aluminum also tends to 'gall' or weld itself to cutting edges, so it's advisable to check and clean any galls off regularly.


Wood work but can't!
Joined: Apr 2002
Posts: 7,381
Likes: 7
Member
Got to go with Reno. The new set of dies will be a big help too.



John
Joined: Mar 2005
Posts: 1,803
Member
I seem to remember that the manual pipe threader in our fitting shop withdrew the 4[?] dies once you got to depth, so you did not have to unscrew the pipe to get it out.


Wood work but can't!
Joined: Feb 2003
Posts: 939
F
Member
Alan.,

Yes I did recall in the Ridge companie they did have one like that and it have special cam on it when you get done threading the alum pipe then hit the lever which it will pull the dies out then you can slide it out but becarefull it don't take much to nick it.

But as other mention a new die and diffrent cutting fluid will work just fine.

Merci.
Marc


Pas de problme,il marche n'est-ce pas?"(No problem, it works doesn't it?)

Joined: Mar 2005
Posts: 1,803
Member
You won't believe this, but we used lard!


Wood work but can't!
Page 1 of 2 1 2

Link Copied to Clipboard
Powered by UBB.threads™ PHP Forum Software 7.7.5