Tips/Tricks for EMT Conduit Bending

[bmxdad]

After spending to much time doing the bends below, I need help ... I need to know what tricks you use to make those offset bends, the ones that go from a box to a surface. There have to be rules or tricks that make those bends second nature... so please share some knowledge ...

View media item 44228

 

[A_Pmech]

Did you read the instructions on how to use a conduit bender?

 

[Charles (in GA)]

Practice, practice, practice. You'd choke if you saw all of the conduit I've run and bent (and wasted).

Best document I've found on the internet. There may be some Youtube videos you could watch also.

http://www.cefga.org/documents/BendingRaceways.pdf

Those don't look like deep boxes. I'm going to tell you now, don't waste your time on anything smaller than a 4x4 deep box. Not even for a single outlet or switch. Just buy a case of them and be done with it.

Those stamped, formed, conduit fittings you have screwed into the boxes caused me nothing but grief. I ended up throwing the remainder of a bag of them in the scrap metal. Screw threads were messed up on the set screws. I had much better luck with the cast pot metal ones such as the Halex brand.

Charles

 

[bmxdad]

Did you read the instructions on how to use a conduit bender?

lol ... not yet, but I will

Practice, practice, practice. You'd choke if you saw all of the conduit I've run and bent (and wasted).

Best document I've found on the internet. There may be some Youtube videos you could watch also.

http://www.cefga.org/documents/BendingRaceways.pdf

Those don't look like deep boxes. I'm going to tell you now, don't waste your time on anything smaller than a 4x4 deep box. Not even for a single outlet or switch. Just buy a case of them and be done with it.

Those stamped, formed, conduit fittings you have screwed into the boxes caused me nothing but grief. I ended up throwing the remainder of a bag of them in the scrap metal. Screw threads were messed up on the set screws. I had much better luck with the cast pot metal ones such as the Halex brand.

Charles

Yea, found out the hard way ... will be returning them tomorrow. Bottom box is a shallow one I'm using to transition to the EMT. Top one is a deep box. More expensive but so much easier. That particular one will have the GFIC outlet, and I'll power two more to the right and three to the left. All six boxes will be using a single 20 amp duplex outlet.

 

[RivennHewn]

These make life easy:

http://www.westsidewholesale.com/gr...ferralID=2d5f807c-58eb-11e4-86f3-001b2166becc

Or Amazon:

http://www.amazon.com/dp/B001HWFRMG/?tag=atomicindus08-20

 

[2Big2Ride]

I ended up using an app for the phone, along with the sticker included on the bender for offsets.

 

[TM98]

These make life easy:

http://www.westsidewholesale.com/gr...ferralID=2d5f807c-58eb-11e4-86f3-001b2166becc

Or Amazon:

http://www.amazon.com/dp/B001HWFRMG/?tag=atomicindus08-20

This usually only makes a small offset to go into the hole closest to the stud but it should work fine as long as that hole is the right size for the conduit.

 

[Charles (in GA)]

lol ... not yet, but I will



Yea, found out the hard way ... will be returning them tomorrow. Bottom box is a shallow one I'm using to transition to the EMT. Top one is a deep box. More expensive but so much easier. That particular one will have the GFIC outlet, and I'll power two more to the right and three to the left. All six boxes will be using a single 20 amp duplex outlet.

Unless you need the 20 amp NEMA 5-20 style receptacle because you have a device or welder or whatever using it, there is no need to use 20 amp rated receptacles. You can get the exact same style/grade/quality receptacle in 15 amp slightly cheaper, and they actually come with the insides of a 20 amp covered by a 15 amp face plate.

A lone 15 amp DUPLEX receptacle is considered by the code as TWO receptacles and is OK to use on a 20 amp circuit by code. A lone single receptacle must match the amperage of the circuit.

Charles

 

[bmxdad]

So a 15 amp outlet is OK on a 20 amp circuit? How so?

If the insides are the same, then why call it a 15 amp? Is it because of the NEMA plug style?

Is there a 2008NEC Reference?

 

[davetulk]

15A "duplex" outlets are rated for 20A pass thru. Thus they are perfectly legal and safe for use on a 20A circuit.

If you have a single outlet on a dedicated circuit, then you should use a 20A outlet or a 15A breaker, but other than certain dedicated things rarely have singles they have duplex.

Because you cannot plug a single 20amp device into a 15amp receptacle the expectation is you cannot draw over the 15 amps. With that said power strips possibly could load more, but the strip should only be rated at max 15amp with over current protection.

Off course the wire still needs to be 12ga min for a 20amp circuit.

NEC 210

That is national code.....your local may have amendments. In my shop I went ahead with 20amp outlets just the same, just gave me a better piece of mind for some reason and if I ever did have a tool that was 20amp I could plug it in. Cost a little more but you can find good deals online...just make sure they are certified outlets.

Dave

 

[Falcon67]

Bending pipe is why I use MC cable.

 

[hammlm]

Its been a long, long time, but I have bent and hung a lot of pipe. I was young and a lot stronger then (hell, maybe smarter, too).

I seem to remember there being specific take-ups for each size pipe, based on the bender you'd be using --- I think 3/4" was a 6" take up. It got quite confusing, until I learned about the 30* offset.

My benders had a mark at 30* -- I also seem to remember that 30* was when the handle was perpendicular to the flat floor with no pressure on it.

If I wanted a 3" offset (that is, running up a wall, and then entering a box or raceway 3" away from the wall, I would make a mark where I wanted it to start, then mark DOUBLE THE OFFSET on the pipe (so in this case, 6" away from the first mark).

I'd bend the first 30* with reckless abandon. Then put the handle of my bender on the ground with the head in the air, and get the second mark lined up exactly with the bending mark ---- rotate the pipe exactly 180* from the first bend and make the second bend --- completing the offset.

I'd set the pipe on the floor, get out my torpedo level and see if the offset part of the pipe was level. If not, I'd massage one or the other of the bends by hand.

Sounds complicated, but really, do 3 or 4, and it's just rote.

Now, I'll sit back and wait for the experts to chime in ---which will give some indication on how well I can remember 25 years ago.

 

[Tyberius]

I consider myself a pretty good pipe bender. I'm better than anybody that I've ever seen do pipe. But I don't do it all that often. So when I start out there are a few problem bends.

Anyway, those offsets are deeper than I would bend - to the second hole. To the first hole, I just eyeball it.

Always know which end you are bending from. That'll get you.

Saddle bends still are a pain in the ***, because you are not bending from the same direction, so you have to measure measure measure.

 

[Rtw5150]

Use a Minnie instead of a one hole strap and you won't need to make a box offset.
They'll keep the back of the pipe 1/2" off the stud and perfectly in line with the first knockout.

http://m.platt.com/platt-electric-s...olts/Erico-Caddy/CD4B/Products.aspx?pid=13228

 

[Cmreschke]

Strap this!

 

[Cmreschke]

Seriously though, yes at 30 degrees the distance between bends is 2 times the offset distance, put your marks at the same spot on the shoe of the bender.

Take up is for 90 degree bends.

Any bend smaller then 2" I typically eyeball and they will be typically less than 30 degree bends.

 

[zmaxmotorsports]

Look up some of jack benfields stuff,hes one of the original creators of emt.

 

[ddawg16]

You should have done that with rigid.

Just kidding.

However, why didn't you just use PVC and run a ground in the conduit?

There is an art to it.

But I bet you now understand some of the advantages a stick built garage has.

 

[zmaxmotorsports]

http://www.google.com/aclk?sa=L&ai=...2368&wl4=&wl5=pla&wl6=75138253248&veh=semLets see if this works.

 

[bmxdad]

Found a GreenLee #1810 offset bender for $70 ... good deal?

 

[Tyberius]

Looks like it. $240 new.

 

[jdieter]

Another way to bend offsets; use the star mark on the bender for both bends. Make the first bend with the handle pulled to plumb, lay the conduit flat on the floor and lay the bender pipe handle tight along the straight section of conduit that was under you while bending (so you carry a line out form the bottom edge of the conduit), make a right angle height measurement off the bender handle to the desired offset, for instance 10", where 10" intersects the top edge of the conduit, make a mark. Refine this mark by ringing the conduit to transfer the mark to the bottom of the conduit perpendicularly. Take the conduit off the floor locate the ringed mark on the star, make the second bend in the same plane as the first. When you have enough second bend done to place the conduit back on the floor, pull the bender handle plumb. Much harder to describe than do or watching someone else do it.

 

[George in Rancho Cordova]

Why not use straight conduit, with a furring strip to space out the brackets to meet the conduit?

 

[bmxdad]

Need to get this done, so found an offset bender on CL ... neat tool.

View media item 44311
Looks good too
View media item 44310

 

[Andybull]

http://www.amazon.com/dp/0872885100/?tag=atomicindus08-20

 

[600SL]

Did 18 of these 3/4" offsets yesterday. I wish they would make an offset bender for up to 4". Did these by hand what a PIA to make 10° bends +/- 1°. I used the bend guide someone published here. I don't know how to attach it but its from Albany Technical Collage.

 

[Eriehunter]

These are the **** if you are doing a lot of conduit.

http://www.evansbenders.com/

 

[bmxdad]

... I don't know how to attach it but its from Albany Technical Collage.

This the one: BendingRaceways.pdf

 

[zmaxmotorsports]

For box offsets in 1/2" I always just put end of bender right on end of conduit for first bend,for second bend I just roll pipe over 180* then mark it 6" from end of pipe.
That's where I put the arrow on bender ,then finish offset.
They all end up the same that way.

 

[bmxdad]

For box offsets in 1/2" I always just put end of bender right on end of conduit for first bend,for second bend I just roll pipe over 180* then mark it 6" from end of pipe.
That's where I put the arrow on bender ,then finish offset.
They all end up the same that way.

Good info

 

[rodm1]

Haven't tried it but this video seems quit good.

 

[bmxdad]

Saw that ... here is another by Polly Friendshuh at Dunwoody College .... its a 5 part series.

 

[600SL]

Did 18 box offsets yesterday and today finished all bending and cutting. This was the first weekend that I haven't messed up a piece of conduit. The previous 3 or 4 bouts of conduit work all met with high scrap rates.

 

[600SL]

This the one: BendingRaceways.pdf

Yes that's the one. How were you able to attach it? For me it said it was too big.

 

[bmxdad]

Just use code like this ... it's called BB code.

 [ URL="https://www.youtube.com/watch?v=G2uEOMwDEJ0"]here is another[/URL]

Remove the space after the first [ to use ...

 

[velocipede]

Polly's videos were very helpful. Thanks for that link.

 

[FordsnFishin]

Being a union electrician, i bend pipe nearly everyday.

Its definitely a thing you perfect with time and experience. But a simple offset or 90 will get you buy in most cases. That bender you got off craigslist is intended for box offsets, which is generally just 5/8". Which might get you buy in some cases but if you get some practice with the hand bender you will be much better off.

The best thing you can remember is the 30 degree mark on your bender. The multiplier for 30 degrees is x2. So if you're doing a 3" offset it would be 3x2=6 inches. 4 inch offset 4x2=8 inches ect...

So measure the offset you need. Say its 3 1/2 inches. Which would be 7 inches. I typically go a inch off the end of the pipe to keep from egging the end so it goes into the connector correctly. so make a mark an inch off the end, than measure 7 inches from that mark and make another all the way around the pipe. Line the front of the shoe of the bender on your first mark, and bend to 30 degrees. Push the pipe thru, rotate the pipe, and put it on your 2nd mark and repeat the 30 degree mark. You should now have your offset. You can check your offset size by laying the pipe on the ground and setting a straight edge against it. (another piece of pipe ect..) Tweak it as needed if its not right.

As for a 90 degree bend, you have to remember that there is going to be a take up from bending the pipe. Depending on the size of pipe it will be different. It should say on your bender what it is. 1/2 conduit is 5", 3/4 conduit is 6". So say you need a 12 inch 90 on 1/2 stick of conduit. 12 inches - 5 inches= 7 inches. So 7 inches from the end of the pipe make a mark. Remember for 90 degree bends you have to match your mark onto the arrow mark of the bender. (should be just past the slot where you slip your conduit thru) Line those up and bend it to where you think 90 degrees is. Now set the pipe down and stick the 90 up, and slap a torpedo level onto it and make sure its a true 90. You can stand on the pipe and push the 90 with your hands to tweak it.

You can always make your 90 a bit long and cut it to the length you need to make sure your accurate as well.

Those two bends should get you through most of anything you need to do.

 

[FordsnFishin]

Btw, for almost any offset i have the shoe of the bender in the air and handle against the ground, it allows for you to easily read how many degrees of bend you are doing.

 

[FordsnFishin]

Box offsets can be bit tricky, cause i dont measure at all and just have a feel for it. But basically put your bender on the end of the pipe, bend it to 10 degrees, push through just past the your bend and rotate, and bend another 10 degrees. Alittle practice and you will do box offsets in your sleep.

 

[bmxdad]

How would you go around a 4x6 beam? Think I might have to us a metal L box ...