Has anyone tried using EMT with pipe clamps?

[OFWW]

Was just thinking, EMT is so much lighter, so why nor use Pipe to EMT adapters and go for it?

Has anyone tried it?

[-MIKE-]

My guess is it would be too flexible because it's so thin. It seems to be getting thinner and thinner, too. Anyone see how thin copper pipe is these days? You can practically put your fingernail through it.

[Puckdropper]

OFWW wrote in news: [e-mail]:

I have not tried it, but I have seen 1/2" black iron pipe bend as the clamps were tightened. I've also played a lot with EMT on the backyard ice rink, and can tell you the 3/4" EMT is probably as flexible as the 1/2 black iron.

It's also a lot cheaper too.

Let us know if you try it and it works.

Puckdropper

[OFWW]

Yeah, the so-called water grade is pure crap. Even looking at a roll of it will cause dents and the tubing to get out of round. Shudder my first memories of picking some up at the local box store instead of my normal supply house and getting that by mistake.

EMT seems about the same, I suppose because steel is a lot less expensive. I think I'll try a short piece first because of the sliding locking clamp and see what happens when it grips the EMT and if it will cave it in or dent it.

[OFWW]

I think I have some short pieces out in the garage, I'll give it a test to see. But yeah, running conduit shows it as flexible, maybe short pieces will react differently?

[Brewster]

I had thought about something similar one time.

Use short stubs of black pipe with the clamps. Install "T"'s on the threaded ends, then street elbows to EMT or other pipe so the system will extend along both sides of a panel glueup. This should eliminate any pipe bowing, assembly issues aside 8^)

-BR

[-MIKE-]

I wasn't thinking about the clamps caving in or denting the steel, although that is a possibility. I was thinking about the pipe bowing in the middle like cheap bar clamps do. It would cause the jaw faces to splay out and could cause poor/lost grip on the stuff being clamped.

[Bob La Londe]

On 5/29/2018 8:23 PM, OFWW wrote: > Was just thinking, EMT is so much lighter, so why nor use Pipe to EMT > adapters and go for it? > > Has anyone tried it? >

EMT is way to light. I can handily bend 3/4 over my knee without hurting my knee.

IMC might be a viable alternative, but I have not really compared strength and price to rigid.

Also, I do not know how the OD for each compares. I don't know if your pipe clamps would go on easily or not. Need to wander over to the box store and find out I guess.

EMT is likely cheapest at the box store, but for rigid or IMC it might pay to check pricing at your local electrical suppliers. Especially if you are buying half a dozen pieces.

[Doug Miller]

OFWW wrote in news: [e-mail]:

My first thought is that if this worked, we'd all have known about it by now, and everybody would be doing it.

Not me, and I don't think it's going to work. Here's why:

1) I think it's *too* light, and is going to flex so much under clamping pressure that the clamp jaws won't even be close to parallel (that is, assuming it doesn't just buckle). EMT is called "thinwall" for a reason: wall thicknesses are 0.042" and 0.049" for 1/2" and 3/4" respectively. The corresponding dimensions for Schedule 40 steel pipe are 0.109" and 0.113". EMT is very easy to bend by hand; bending pipe or rigid conduit requires hydraulics.

2) I may be mistaken, but I don't think you're going to find the kind of adapter you need. Rigid electrical conduit is the same size as water pipe, with the same size threads -- but the only EMT-to-rigid adapters I've ever seen have female threads, probably because rigid has male threads on each end. Sure, you can add a pipe nipple too, but now you're starting to move into Rube Goldberg territory...

3) Even if you can manage to somehow adapt the clamp headstock to the EMT, I very much doubt that the tailstock will grip it tightly enough for clamping, because the tailstocks are sized for pipe and EMT is noticeably smaller: actual outside diameters are 1/2" EMT, 0.706"; 1/2" pipe, 0.840; 3/4" EMT, 0.922; 3/4" pipe, 1.050 -- and 1" EMT (1.163") is >10% larger than 3/4" pipe.

4) If you *do* manage both 2) and 3), I think that once you start tightening the clamps, the gripping mechanism in the tailstock will crush the EMT. Like I said, it's called "thinwall" for a reason.

If you decide to try it anyway, though, best of luck, and let us know how it turns out.

[russellseaton1]

ing the clamps, the

called "thinwall" for a

I doubt the gripping rings on the tail end of the pipe clamps will grip the EMT. The gripping rings are chromed steel. The EMT is chromed or some ki nd of gray plating. Its slick. I don't think the rings will grip the slic k EMT pipe. So no clamping force. I don't think it will grip enough to ev en dent the thinwall EMT. It'll just slip.

[Clare Snyder]

That just depends which grade you buy. L is still L, K is still K and M is still M. L is the "standard good" pipe, and M is the crappy cheap stuff that no self respecting plumber would have used 40 years ago.

K is the heavy stuff.

Now FITTINGS, I will agree. Used to be K or L weight copper, now much of it appears to be the thickness of M, if that.

[Clare Snyder]

Roll copper has ALWAYS been soft because it is annealed copper. Hard straight copper is what is "generally" used for water plumbing - M has always been thin. M is now stocked as "standard" at the Borg and other big box centers, L is still available and is "standard" at a good plumbing supply - where the cheaper lighter M is also available.

There are standards - which have not changed.

[Clare Snyder]

If your aim is to make a cheap flexible useless clamp, just go buy a cheap chinese one and save the trouble????

[Clare Snyder]

EMT is NOT chromed, it is electro-zinc plated.

[OFWW]

Possibly but it is worth a check, many clams aren't high pressure clamps anyhow so depending on use it may not make that big of a difference. BTW, I do have rigid pipe benders for 1/2 & 3/4" in my garage. I used to bend pipe on electrical installations for explosion proof connections.

EMT to box connectors, work with rigid nipples as well. They typically will bottom out because they are a straight not a tapered thread but they can be tightened.

Last I checked the OD of 3/4 pipe was smaller than EMT. and yes the tail stock would be the first thing to check out since if it did fit will it hold without damage the conduit.

I hope to give it a go this week sometime. It is just a question that nagged me for years. Thanks for your thoughts.

[OFWW]

LOL, I have American made newer F clamps that are mighty weak. :) It is surprising that many don't publish the max clamping ft/lbs.

[krw]

I've had that problem with any pipe clamps. I threw them all away and bought Besseys. No problems with them.

[krw]

'L' copper is available at the BORG, too. It costs about 50% more than type 'M' but it is available. I use it for compressed air.

Like the size of a 2x4? ;-)

[Clare Snyder]

Yes, and "american made" really doesn't mean anything anymore - "made in the USA of world sourced parts" just means they put in the last rivet or pin and put it in a box.

[Leon]

I'm sure this is obvious,,,,, what is EMT? Emergency Medical Team? ;~)