Conduit Question

Can conduit be welded? I'm looking at 1 1/2" EMT sold at HD. I would like to use it in a project and would like to ARC or MIG it to A513 mild steel. Conduit is much less expensive that black pipe. Thanks.

Reply to
Frank A.
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yes it can, it is mild steel pipe, and it is galvanized !!!!! it can be welded, but it will produce a nasty fume, and a white poder like substance. use a fan to blow away the fumes, work in a well ventilated area.

I built all kind of stuf out of EMT, half of my kids playscape is EMT with various sizes from a 1/2" to a 1-1/2" also have lots of shelfs, metal racks, and what not made with EMT

if you do not have a pipe nother or hole saw to make perfect 90 degree joints, cut the pipe and hammer pipe wall to an oval shape.

Reply to
acrobat-ants

Most of it already has been. Don't be surprised if your wonderful welded space frame vehicle goes over its first bump, then you find that the handy-sized piece of conduit you'd used as a structural member then splits right along the seam line.

It's usually either painted or galved too. Both are a pain to work with. Steel is cheap, time is expensive. Your call.

-- Die Gotterspammerung - Junkmail of the Gods

Reply to
Andy Dingley

Yes. I've done it many, many times both with TIG and O/A.

IMO, pretty thin wall for stick or MIG. Ernie could probably do it.

Much lighter too if it's strong enough for your app.

Ted

Reply to
Ted Edwards

Yes it can although electricians don't weld it.

My first welding project involved 1/2 inch EMT as did several projects afterwards. It's cheap, easy to bend, made into "trusses" can be very strong, and has a nice rust proof coating already. The "finished" project was a success.

I had a hard time re-learning welding using it. Starting with a Lincoln AC-225, I tried all sorts of alternatives including making a rectifier for DC welding. I ended up favoring 3/32nds 6011 on DC+ at 85A. The 6011 has just a bit of slag which was a problem with 6013. 6011 didn't fuss with the zinc in the weld. Eventhough it burns hotter than most others, I had better luck using "it" considering the tight curves and fillets that 1/2 inch pipe has and the poorly fit joints I managed to make. I learned to make short welds, stop for cooling and then weld a bit more. Since that time I've acquired a MIG machine and now use it for all the thin stuff. I still have the buzz box for all the meaty stuff.

It's much weaker too.

Note: As you probably already know, any smoke is not good to breathe. Although I don't think gaseous zinc is any worse than gaseous aluminum or chromium, stay out of the smoke plume. Since we are basically blind while welding, we can't always see the smoke since we're busy watching the work. Controlled breathing (or a respirator) is the best advice I can offer. See:

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good information on zinc's "Metal Fume Fever" and other stuff that if taken too seriously will make you want to forget welding or even BBQing. ;^)

Reply to
Zorro

yeah,.....well..... i would not use it as a racecar frame, but the 3/4 inch EMT surely hold my 200 pound ass, when climbing the "monkey bar" on my kids playscape.

same applys to the ladder made out of 3/4 inch and 1/2 EMT also used on the playscape.

Reply to
acrobat-ants

wow , you used a stick welder on a 1/2 inch conduit ????? I got to give you credit !!!!

I have good result with my baby MIG (135) using .024 solidwire with shielding gas

I don't get the "stick welder" out unless it is it is 3/16 or heavier material.

the baby mig will do just fine for others.

Reply to
acrobat-ants

Lots of time it is good enough. Last weekend I wanted a stand to hold my bike while I worked on it. I didn't want to pay $100+, and also I wanted it now. So an hour with the MIG and some 3/4" conduit I had in the corner and I had a working stand. Well, I did use a piece of water pipe as the main support tube, and an old C-clamp with a couple pieces of angle welded on to hold the top tube of the bike, but that was all stuff I had laying around. If I want to be precise I use winmiter to print out patterns to fishmouth the tubing, but for this I just used a 4 1/2" grinder and did it by eye. The only problem is now that I have to build one for my buddy.

I wouldn't use conduit for anything structural or automotive or important, though.

Dave

Reply to
Dave Wilson

Yes, you con du it!

Sorry, I couldn't resist

Reply to
Andy Wakefield

Thanks for the info.

Reply to
Frank A.

Winmiter is very cool.

Reply to
Frank A.

I have searched for winmiter, but I keep coming up with dead ends...links that don't work. I even tried the IHPVA website....nothing. Anybody know where to get a copy of winmiter?

Thanks

Reply to
Scooter68

Here's TubeMiter:

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Look for tubemiter.exe

According to the guy quoted below,

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has it somewhere (in the archives?). I couldn't get the site he mentions to work.

Reply to
Zorro

Yes! I had been thinking of using it for a long time. Recently, I needed to make a new stand for a patio umbrella. The wood one I made finally rotted out. It would be a horizontal "X" with a vertical pipe to hold the umbrella pole. I went to HD and looked at the large EMT and the tubing for chain-link fences. The EMT had the right ID for the pole. One 10" section was cut into two 4' and two 2' sections. I sanded off the galzanizing back about 3" from the ends to be O/A welded. In order to make the saddle joints I used a program called WINMITER. You enter the sizes of your two tubes and the angle where they meet. The printout is a paper you tape around the tube. Then grind down to the line on the paper. Presto, a perfect joint. Clamp it up, weld, clean it up and paint. Works great!

Reply to
Ken Moffett

once you have the fishmouth drawn on a piece of say...black pipe...,how do you cut it other than a tube notching vice and hole saw? if you have those you wouldn't need the template anyway. forgive me if I'm missing the obvious.

L

Reply to
Larry Silverberg

You can use a chop saw to make "two" cuts at an angle on opposite sides of the pipe. You end up with two sharp points 180 degrees apart and two concave pits offset by 90 degrees. You could weld it like that or further finish with a bench grinder to make the cut closer to your line.

Reply to
Zorro

Oops! That should have been one 4' section and three 2' sections.

Reply to
Ken Moffett

I downloaded it last night from: ftp://ftp.ihpva.org/pub/software/winmiter/

I used it today to fit some 11/2" EMT using a angle grinder to cut out the notches. I found it necessary to cut back the points a good bit to make the fit.

Reply to
Frank A.

Use a grinder or a file, maybe? Preferably in that order.

Reply to
jerry_tig2003

Whenever I try to go to that link, it causes my browser to freeze for some reason. Not to fret though, someone was kind enough to send it to me.

ftp://ftp.ihpva.org/pub/software/winmiter/

ends...links

Reply to
Scooter68

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