expanding or crimping 1" EMT conduit

[Throbbin Rods]

Working on expanding the blind to fit the newly fit up duckboat. The frame is made of 1"EMT as far as I can determine. Anyone know of tools or methods to either expand or crimp this stuff? I thought about clamping the old stuff in the vice, heating the end of the new stuff cherry red and forcing the the two together. I would love to hear any suggestions.
Thanks,
Bill

 

[readhead]

Can you use emt couplings?

 

[MEngineer]

how about looking into a wirsbo style tubing expander

 

[Farrier]

Borrow a 110v mig welder and use flux-core 0.23 wire to weld pieces together. Add a small strap of steel to reinforce if necessary

 

[Slugranch]

Or find a swaging tool, heat the end and let it air cool, then swage it, reheat, and quench it in oil. Should work.

 

[theoldwizard1]

Good luck ! I have been looking for something like this for years for similar projects.

EDIT : Not exactly what you are asking for, but very close ...

Use 1-1/4" EMT and then buy a 1-1/8" tail pipe expander (< $10 on eBay). Lube the working parts of the expander before using. Go slow. EMT is pretty cheap stuff so you might split the seam.

I would really like to swage down one end, but I have not found anyway of doing that, economically.

 

[gregtwojeeps]

Can you use emt couplings?

THis^^^ using set screw couplings. I assume the OP wants to break down his stand and put back together one EMT at a time ?

If he really wants to enlarge one end of a EMT so another piece can be slid in to it, he will need a swage punch, like in the link. Except the 1 1/8 " expander is $85.00. One can be made if their shop has the tools needed to do so.

http://www.mscdirect.com/product/details/92773605

 

[Throbbin Rods]

Can you use emt couplings?

I tried those EMT couplings in the past on smaller emt and they just wouldn't maintain the structure with any integrity. I have a wire feed with shield gas but am not good enough with it to **** weld those pieces. I wish I could.
Thanks for the suggestions. The idea is for the entire blind to stay in place for several thousand miles over the season, and to come off in one piece for the off season.

 

[Throbbin Rods]

how about looking into a wirsbo style tubing expander

Isn't the wirsbo type for use with PEX?

 

[gregtwojeeps]

I tried those EMT couplings in the past on smaller emt and they just wouldn't maintain the structure with any integrity. I have a wire feed with shield gas but am not good enough with it to **** weld those pieces. I wish I could.
Thanks for the suggestions. The idea is for the entire blind to stay in place for several thousand miles over the season, and to come off in one piece for the off season.

Then slip the set screw couplings over them, tighten them down and then weld them on with your MIG. Then, remove the screws. Stronger than **** welds. Just be mindful that EMT has some nasty fumes when welding on it.

 

[MEngineer]

Isn't the wirsbo type for use with PEX?

Yes and no. The wirsbo branding is specifically for pex, but there are a fair number of expander tools of the same style for use with copper and other materials.

 

[Dragfluid]

Rather than the set screw type of coupler, try the compression fitting version.

 

[Marctrees]

If you go the compression coupling method, make sure you get the ALL steel version, not the one with the cheap pot metal center part. Marc

 

[Marctrees]

Here ya go - http://www.tarps.com/chrome2.htm

http://www.tarps.com/images/fc.jpg

https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=1"+emt+framing+coupling

 

[Marctrees]

one more - http://idahocanvas.com/id48.htm

 

[matt_i]

As mentioned the thing that is hell to deal with in EMT is the galvanization...which must be removed unless you want to go down the road of the toxic fumes.

Easier thing to do with a MiG welder is to drill some holes, crossways thru both walls of the coupler, and do a "plug weld" which is basically striking the arc inside the hole once fully assembled, and then moving the arc around in a circle(s) until the hole is filled up.

 

[PugetDude]

Try this:

http://www.harborfreight.com/small-tail-pipe-expander-69550.html

If it doesn't work, you're only out $6

 

[Stuart in MN]

Try this:

http://www.harborfreight.com/small-tail-pipe-expander-69550.html

If it doesn't work, you're only out $6

I was thinking of the same kind of device, but that one appears to only go down to 1 1/8".

 

[-Brent-]

Maybe this is hokey but what about banging down the ends flat and drilling a hole for a nut/bolt?

 

[APEowner]

Maybe this is hokey but what about banging down the ends flat and drilling a hole for a nut/bolt?

Or, to take this a step further use a setscrew coupler but use the setscrew hole as a pilot hole, drill right through the assembly and then nut and bolt.

 

[theoldwizard1]

Try this:

http://www.harborfreight.com/small-tail-pipe-expander-69550.html

If it doesn't work, you're only out $6

Too large.



Now, that isn't saying that an ambitious person could not take it apart file/sand/grind a little bit off of each of those wedges to get the minimum ID down to about 0.900".

 

[theoldwizard1]

Maybe this is hokey but what about banging down the ends flat and drilling a hole for a nut/bolt?

Or, to take this a step further use a setscrew coupler but use the setscrew hole as a pilot hole, drill right through the assembly and then nut and bolt.

Come on guys ! How about an "elegant" solution !

1" EMT is 1.163 OD with 0.057 wall, so the ID should be about 1.049. You would probably want a swaged tube to be 0.900-0.950 OD to easily fit inside. So the goal is to take a 1.163 OD stell tub and make it 0.900 OD.

Get a block of steel about 3x3x2 (or 3" round bar, 2" thick). Have a machinist put a 0.900 hole through the center and then taper it to 1.200 on one side. We now have a swaging die !

Now here is where we need to do some experimenting. Lube the tube and die with some grease. Tap the die with a hammer until the tube well seated in the die.

1. Take a 4x4 and drill a 1/4" hole through it. From one side, drill 1-1/2 hole at least 2" deep. Find the longest 1/4 bolt you can an pound it in flush from the side with the small hole. A piece of good straight rebar would work also. Take end of your stick of EMT with the die on it and place it over the bolt/rebar. Drop. Repeat. Repeat. Repeat. Repeat.
2. If this does not work, it is because the mass of the EMT is not enough to "drive" it through the die. You need to clamp some weight on to the EMT a couple of inches above the die and try again.
3. If you have a way to firmly hold the EMT horizontally, just get a 1-1/2 impact socket and place it centered over the hole in the die and smack using a hand sledge or dead blow. If you are real fancy you can probably use an air hammer with a mushroom head "chisel" to pound with.

 

[theoldwizard1]

This works (I have done it), but boy is it "redneck". Completely unrealistic for multiple "connections" that need to be assembled and disassembled quickly and easily !

Get a piece of 1" hardwood dowel rod at least 6" long, 8"-12" would be better. Mark the center with a Sharpie. Whittle the one side down until you can pound it into one piece of EMT, up to the center line. Now whittle the other have down until it slides easily into the other tube.

In my case, I was making a temporary 20' antenna mast so there was going to be a lot of side load (when the wind blew) at the connection that might snap that dowel. I took some pieces of 1/8"-3/16" steel rod about 8"-12" long and, using some duct tape, placed 4 of the evenly spaced around the joint. Then I used 4 worm gear hose clamps, 2 on the top piece, 2 of the bottom piece, to clamp it all together.

I had a 20' un-guyed mast lashed to a 4x4 fence post with my antenna on top for a couple of days ! If there was going to be a kink, it was not going to be at that connection !!

 

[ssdave]

http://weldingweb.com/showthread.php?43691-Swage-for-nesting-1-2-quot-emt-conduit

 

[theoldwizard1]

Another idea, that is expensive, unless you own a lathe.

Get some 1" OD, 0.120 wall steel tube, cut into 6" lengths. Have your machinist buddy cut down 1/2 of the length to 0.90 OD (or whatever slides easily into the EMT).

Place these half way inside one end of the EMT. Drill and tap a hole for a #10 machine screw all the way through. Use a 1/4" #10 button head Allen screw to secure everything. Spend the extra and get stainless screws so they don't rust.

 

[theoldwizard1]

http://weldingweb.com/showthread.php?43691-Swage-for-nesting-1-2-quot-emt-conduit

WOW !! Some people a lot smarter than me really put some time into this !

If you can't push it through a die in 1 pass, 2 or 3 successively smaller dies might work. Griping the tube against the force of a hydraulic ram (bottle jack) is also an issue.

 

[PugetDude]

Too large.



Now, that isn't saying that an ambitious person could not take it apart file/sand/grind a little bit off of each of those wedges to get the minimum ID down to about 0.900".

Or, just take one wedge out and use a smaller o-ring...

 

[Flail]

Use emt couplers and braze them to the emt.

 

[RWorth]

I just had a thought, go to whoever does your hydraulic lines and see if the crimper will shrink the emt.

 

[sberry]

If it can be welded take a few minutes and learn to do this or shove the machine off to someone that can. Inch emt welds very well with small wire.

 

[Throbbin Rods]

These are some great ideas. I have no machinist equipment or knowledge. . I am working one handed due to surgery to repair a broken wrist so some of these thoughts are just unmanageable for me. I did order the 1" tubing splicers from Marctrees first post. I believe those will do the job for me. I just need a way to add a short length of 1" EMT to a longer bone. If I run a couple of self tappers in there at each end that should keep it together. Goal is to have the whole thing as one unit for easy on and off the boat. Thanks much for all the suggestions. BTW, hammering in a hardwood dowel was my next choice.

 

[rkevins]

I have swaged emt with a hammer you flatten 2 sides slightly then turn and do the other sides, may be easer with a brick hammer but never tried then drive the pieces together

 

[Joemctag]

I make a lot of things with emt so I bought solid aluminum round bar in different sizes and had a machine shop turn down short lengths to a diameter where they fit inside the emt for sleeves. Fasten with thru/bolts or pop rivets. 4 to 6 inches long. For some larger emt sizes, pipe, mic or emt can be a sleeve. I actually made tables with all the I.d.s and o.d.s for all the sizes of pipe, mic and emt. There’s also something called 20 series fence tube that chain link fence companies can sell you that has a couple different sizes also . Thick enough to weld but still light. Now I’ve got a box full of short lengths of pipe and tube so I can play with it to see how they fit with each other without trying to figure it out from the tables.

 

[DEXTERBBQ]

You can buy "Kwik-Fit" EMT conduit that has one end already expanded to accept another piece. Unfortunately the smallest size is 1-1/4 inch. Google Allied conduit Kwik-Fit. Some electric distributors stock various sizes (starting at 1-1/4). Saves a lot of labor on a job by having the coupling formed into the conduit.

I know its not 1" like the op talked about but I thought the information might be useful to someone else.

No affiliation to Allied but I do work for a wholesale electrical distributor.

 

[fitter30]

1" emt is 1 .049
3/4 SCH 40 black pipe 1.050
Screwed ****** with bolts & nuts drilled through emt and ******.

 

[kbs2244]

Use the all steel coupler for strength and epoxy for ease of assembly

 

[Bert_]

1" emt is 1 .049
3/4 SCH 40 black pipe 1.050
Screwed ****** with bolts & nuts drilled through emt and ******.

This is exactly what I was thinking. Use 6-8" pieces of 3/4 black pipe for the coupler. Just slide it inside the emt. I would probably use some short tek screws instead of nuts and bolts.

 

[sberry]

If you don't need to take apart nothing beats welded. There is some gave on it but not as thick as water pipe. Work a little to keep head out of fumes advent with a super gentle breeze or work outside. You can cope inch with bull nose av snipe, make it fit tight and easily welded 023 and even 030 for some.
For **** weld some 120 or 150 and scuff the ends. Noodle the weld around it.

 

[sberry]

Old whiz,,, you are a guy who should absolutely have a 140 mig welder. I got a cousin lives by you bought one like new, had 1# of wire thru it, gas bottle for 150$.

 

[theoldwizard1]

I make a lot of things with emt so I bought solid aluminum round bar in different sizes and had a machine shop turn down short lengths to a diameter where they fit inside the emt for sleeves. Fasten with thru/bolts or pop rivets. 4 to 6 inches long.

By far, THE BEST SOLUTION !

It can be 1" OD aluminum tube, with a 0.1875 or 0.25 wall. #10 machine screws would work it the aluminum was tapped. You could use a steel tube if you don't care about rust.