How to use a conduit bender without angle lines?

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Old 05-11-13, 01:02 AM
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How to use a conduit bender without angle lines?

Most benders I've used have lines such that when your conduit is lined up with them you have bent your desired angle. But I ended up with this one recently: Gardner Bender 930B

As you can see in the photo, there are no lines, just arrows. Near as I can tell, when the tiny arrow is perpendicular to the unbent conduit that's the angle. Well, if I could eyeball a perfect 90deg of a tiny arrow with a 10' section of conduit hanging off the thing under it's own weight I wouldn't need angle marks at all because I'd be a superhuman and could just see the angles!

It's got built in 90 and 45 degree bubble levels, so doing those bends is extremely fast. IF you've got a perfectly level floor somewhere -- something that I haven't been able to find on my entire property. Still doesn't help you with 22.5 or 30, etc. Handle up is 45.

The freaking thing has me fuming. My last attempt ended up looking like an intoxicated snake since none of the offsets matched. Not even close. And of course, there are no instructions to be found anywhere on the 'net.

There's gotta be some trick to this?
 
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Old 05-11-13, 03:37 AM
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Old 05-11-13, 04:23 AM
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That is the bender I mainly use and I like it a lot. Here is the trick and maybe a few more:

To catch the angle you want (30, 45 22.5 etc) You site down the bender. Looking directly above your bend, use the bump where the handle inserted in the bender. (see picture) Line up the angle mark of the angle your are looking for with the bump, kind of like your lineing up the sites of a gun, and the bend should be that angle.

As you pointed out, the handle straight up is 45 degrees. If you notice, the mark for 45 degrees, and the bump, line up with the handle straight up.

Here is another handy tip: If you want to bend an offset that is a certain size, just double that measurement and make two 30 degree bends that far apart.

For example: You want a 9" offset. Make two marks on the pipe 18" apart. Line the marks up on a reference point on the bender, doesn't matter where, as long as you use the same point on the bender. Make two opposite bends that are both 30 degrees. Your offset should be 9" if you did it right.

You might also know this but here it is anyway: When bending a back to back 90's, or bending on the other side of the pipe you measured from, place the measurement on the "B" mark on the bender. Your bend should be the correct measurement.
 
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Old 05-11-13, 01:49 PM
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Thanks for the detailed response. That sight is the trick I was looking for. I had noticed that bump earlier, but when I realized shifting your view a couple inches either way would cause it to line up with something else I abandoned that idea. I suppose it's easier to make sure your feet are centered around the bend than to eyeball something else, but it still seems very subjective to me.

What do you do though when you're bending in the air, with the handle on the ground? In fact this is how I do more than half my bends. For offsets, once you to your first bend, spin the tube around and advance to your second mark, the first section is pointed straight at the ground and in the way. Or you may have a couple 90's and kicks already done at that end of the tube. Either way, it's gotta be done in the air a _lot_ of the time.

This is where the parallel lines really help out. I think the only precise way with this bender would be to use a magnetic torpedo level on the tube and a plumb bob in one hand to do the sighting.

Here is another handy tip: If you want to bend an offset that is a certain size, just double that measurement and make two 30 degree bends that far apart.
Yeah 30 is an easy one to remember for the 2.0 multiplier but I find myself using 10 and 22.5 more often... just two more numbers to remember, 6.0 and 2.6. For a box offset of 7/16 or 1/2 the marks are too close for higher degree bends. Seems like a good idea to me to keep the marks at least about the bend radius apart, but I admit I haven't had the guts to try it with just 1" between them. Something tells me it wouldn't work so well.

This particular bender requires quite a bit more unbent tube between the hook and the arrow than others I've used. Minor annoyance.

When bending a back to back 90's, or bending on the other side of the pipe you measured from, place the measurement on the "B" mark on the bender.
Heh when I looked at mine and realized it had no star or notch I was quite disappointed. But that was the _one_ piece of information in the so-called 'manual'... 'B' and '*' are the same. I still don't have a notch; maybe it's that 'A' arrow. Haven't had a need for it yet.

I've already ordered a 'Big Ben' type to use alongside this one. It seems much better suited for in-the-air bends and use on an extremely unlevel surface. Like say a 100 year old barn which has settled over time and racked and feels like a carnival funhouse walking through it. <--- my current project.
 
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Old 05-11-13, 02:03 PM
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Congratulations! You own the son or grandson of the benders I own, and the only ones I want to own. Chandler has already posted the link to the instructions, and Tolyn gave you some helpful tips.

To add to what they've said, I carry three levels to use when I'm bending pipe - with any bender. One is a Stanley FatMax XtremeŽ. With the rotating bezel, or vial, in that level, you can match any angle. The second is a Greenlee level that has four vials, set at 0[SUP]o[/SUP], 30[SUP]o[/SUP], 45[SUP]o[/SUP] and 90[SUP]o[/SUP]. plus a screw-clamp for mounting it to the end of the pipe. That 30[SUP]o[/SUP] vial is just too handy when you're bending offsets. The third is a No-dog offset level. The name says it all. You attach it to the end of a pipe you're bending an offset in, center the bubble, pull the first bend, turn the pipe over with the level still in place, center the bubble again, and pull the second bend. Take the level off and lay the pipe on the floor. It'll lie flat. No dog-leg.

One add-on to one of Tolyn's tips:
Line the marks up on a reference point on the bender, doesn't matter where, as long as you use the same point on the bender. Make two opposite bends that are both 30 degrees. Your offset should be 9" if you did it right.
That includes making both bends while facing the same way on the pipe.

My last attempt ended up looking like an intoxicated snake since none of the offsets matched.
I don't know how much pipe you've bent, but that happens. We used to get helpers who hadn't bent much pipe, and they would get mad and frustrated when it didn't turn out just right the first time. Or the tenth. That's OK. That's what happens when you're learning.

I'll tell you what I told them, "If you haven't f***ed up some pipe then you haven't bent pipe." Seriously. I've now run literally miles of pipe in every known material (I think). A fair amount of that had to be bent, and I promise you I contributed my full share to the recycling company. It's part of everybody's learning curve.
 

Last edited by Nashkat1; 05-11-13 at 07:48 PM.
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Old 05-11-13, 02:19 PM
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Core, I realize now that you've been bending pipe for awhile, and it's just the different bender that's got you a bit frazzled. Having read your second post, I'm tempted to go back and edit a bunch of the "Step 1, Step 2" language out of my first reply, but I think I'll leave it for those readers who don't have as much experience. Hope you don't mind.

What do you do though when you're bending in the air, with the handle on the ground? ... For offsets, once you to your first bend, spin the tube around and advance to your second mark, the first section is pointed straight at the ground and in the way.
I don't own a factory handle. If I ever did, it's long since lost. The handle I use is a 4' section of RMC that I cut and threaded on the job one day. Not only does the extra height help save my back when bending "upside down," it provides more ground clearance.

I think the only precise way with this bender would be to use a magnetic torpedo level on the tube and a plumb bob in one hand to do the sighting.
A plumb bob? Isn't that a carpenter's tool? This is where the levels I linked to in my first reply can really help out. Especially the No-dog.
 
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Old 05-11-13, 02:36 PM
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To add to what they've said, I carry three levels to use when I'm bending pipe - with any bender.
Now THAT's what I'm talking about!! That's a hardcore setup right there. Seems like you can't go wrong with all that. Sounds like I'm about to spend some more money.

I'll tell you what I told them, "If you haven't f***ed up some pipe then you haven't bent pipe."
Good one! I'll use that line on the scrap man when I turn in my pipe. I was seriously contemplating just saving it all for welding practice to avoid the shame.

Core, I realize now that you've been bending pipe for awhile, and it's just the different bender that's got you a bit frazzled.
No, actually I've been bending pipe for exactly 1 week now, but I did my trig homework first. So your advice was appreciated. I started out on 3/4" with a couple different benders I had previously collected and everything went smoothly. Only when I started the 1/2" runs with this other bender did I have all these problems. It was the upside down work, with having no visual frame of reference on this one, that screwed me up. I'm not sure even sighting will work so well upside down since you don't know when you're looking from "exactly below" your bend. I think with the uber-levels setup will help immensely.

A plumb bob? Isn't that a carpenter's tool?
It is? I didn't know, I'm not a carpenter. Rats. And don't tell me J-nails are for plumbers?
 
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Old 05-11-13, 03:06 PM
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The level is a good way to go, PROVIDED your floor is level Gotta have a good reference point, and a sloped loading dock ain't it.

I would be doing figuring on an assignment in my Residential and Commercial Wiring course (way back when) in the evening, and wifey would look over my shoulder and ask why I was dealing in sines, cosines and tangents. It's all in the math.
 
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Old 05-11-13, 04:30 PM
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No, actually I've been bending pipe for exactly 1 week now, but I did my trig homework first.
Cool! What's the constant for a 45[SUP]o[/SUP] offset?

Only when I started the 1/2" runs with this other bender did I have all these problems.
I'm not fond of bending vermicelli either. Afraid I'll kink it if I look at it.

One fun gig was when the foreman on one job decided he wanted to use a fair amount of 1/2" pipe with at least that much 3/4" pipe rising out of a couple of troughs, and he wanted all of them to be bent on the same radius. After enjoying the fussin' and cussin' for awhile, he asked if any of us had a different 3/4" bender. I said sure, got my trusty GB 910 3/4" out of the car, and we bent all of the 1/2" risers with that bender. At least 700 of them, IIRC, with no kinks, but you had to keep the pressure on the whole way through.

It was the upside down work, with having no visual frame of reference on this one, that screwed me up. I'm not sure even sighting will work so well upside down since you don't know when you're looking from "exactly below" your bend.
When I'm bending an offset in a small pipe, I pull the "away" bend first, on the floor. Then I stand the bender up on its handle, rotate the pipe, and slide it forward to the closer mark. The pipe now looks like a check mark. The bent part is out in front of me and running more-or-less level to the floor. Is this not how you're doing it?

Yes, the levels will help. One more thing that will help, if you haven't already learned it, is to run each mark all the way around the pipe, so it's still visible when the pipe is rotated.

Every so often I touch up the arrows and other reference marks on my benders with a marker, but that's the only time I use a marker for pipe work. The marks on the pipe are only made with pencil.
 
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Old 05-11-13, 04:39 PM
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I very rarely bend in the air. When bending an offset (on 1/2" or 3/4"), you do not have to lay pipe flat on the ground. Just put the bender on the 2nd mark, straighten the pipe to prevent the dog leg, and just push the bender down with your foot. EMT bends pretty easy. Also if you over/under bend the pipe your can "tweek" it by just pushing it on the floor to un-bend it or bend it more with a bender. I call it bending by braille.

Here is one more trick (more bending by braille): Say you need an offset that is 10", but you can't use the 30 degree trick. Make your first bend no matter what the angle. Then lay the pipe along a straight edge (bender handle, another pipe, etc) with the side your 2nd bend will be on away from the straight edge. Measure, holding the tape measure 90 degrees to the straight edge your offset, in this case 10", and mark that spot on the pipe. Place the "B" mark at that mark and make the bend until the pipes are parallel.

With box offsets, you just want to "kiss" it pipe with both bends. Again, you can do them both on the floor. Or you can cheat and use one of these: Greenlee 1810 Little Kicker Offset Bender For 1/2" EMT - Amazon.com I use ours all the time.
 
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Old 05-11-13, 05:25 PM
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The bent part is out in front of me and running more-or-less level to the floor. Is this not how you're doing it?
Yeah, that's how I do it. Which means the second bend is made in the air, which was what I was trying to avoid with this bender. If that second bend doesn't end up right (remember we're sighting totally differently from the first one now) I have to tweak it and that rarely turns out well. I suppose I'll get better at that.

Yikes that Greenlee L97 isn't exactly a cheap level. I'm not exactly sure what I'd use the laser for. The L77 seems to be the same thing at 1/3rd of the price and is just missing the laser. How often to you use that laser on it?

Yes, I started out marking all the way around the pipe with pencil. I don't use marker only because it sure wouldn't look pretty.

Just put the bender on the 2nd mark, straighten the pipe to prevent the dog leg, and just push the bender down with your foot.
Hmmm it never occurred to me to just smash it against the floor like that. I'd be afraid that it would have the tendency to slightly unbend my first one. And lots of times there's a heckuva lot of bends on the other end.

The run that was giving me fits last night was: From fixture, box offset to underside of joist, 90 along beam, 90 towards floor, offset into stud cavity, box offset for switch box. I don't remember if I would have been able to do that on the floor or not with all that 'stuff' hanging off. I was determined not to cut the stick. Now it's thrown in my front yard. (Second attempt worked)

Measure, holding the tape measure 90 degrees to the straight edge your offset, in this case 10", and mark that spot on the pipe. Place the "B" mark at that mark and make the bend until the pipes are parallel.
Now that's ingenious! It works out spot-on eh even though it's not a 90? Wow definitely going to try that. Hmmm measuring along an extended straight edge might be _exactly_ the trick I was looking for, for the following question I wasn't going to bother you guys with:

Say you want to go from a fixture mounted on the underside of a joist, across them and then up towards the ceiling and then turn 90 so you're parallel along a joist. The "easy" (math wise) way is to do an offset before the 90. But I try to save myself the extra bend and do a single kick before the 90 instead of both bends in the offset. I couldn't come up with a way to calculate it so I just eyeballed it each time and unbent the kick until it hit the wood. Worked out ok. Usually. I was starting to think that the marginally easier wire pull and degree savings wasn't worth the fuss. But a variation on your trick might work for that.
 
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Old 05-11-13, 08:29 PM
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Yeah, that's how I do it. Which means the second bend is made in the air, which was what I was trying to avoid with this bender. If that second bend doesn't end up right (remember we're sighting totally differently from the first one now) I have to tweak it and that rarely turns out well. I suppose I'll get better at that.
You will, and the no-dog level will help. The main trick is to sight down the pipe and tweak it back and forth until the first bend is as straight up, relative to the bender handle, as you can make it. That's what Tolyn was saying earlier.

Yikes that Greenlee L97 isn't exactly a cheap level. I'm not exactly sure what I'd use the laser for. The L77 seems to be the same thing at 1/3rd of the price and is just missing the laser. How often to you use that laser on it?
Never? 'Cause that's not the one I own? Mine is an L77. I somehow grabbed the wrong url, and I didn't test the link before posting, which I try to always do. My bad. I've fixed the link in that post now, BTW. My laser level, FWIW, is a separate tool that I use for layout, not pipe work.

Yes, bending both halves of an offset on the floor works. You can always tweak any straightening back out by hand.

The run that was giving me fits last night was: From fixture, box offset to underside of joist, 90 along beam, 90 towards floor, offset into stud cavity, box offset for switch box.
I always bend box offsets last. On that stick, I would've bent the two 90s first, then the offset into the wall, and then the two box offsets.

That said, that's a very ambitious set of bends!
(Second attempt worked)
Well done!

It works out spot-on eh even though it's not a 90? Wow definitely going to try that. Hmmm measuring along an extended straight edge might be _exactly_ the trick I was looking for...
That works, but you have to measure your offset by
Originally Posted by Tolyn Ironhand
holding the tape measure 90 degrees to the straight edge,
not along the straight edge.

Say you want to go from a fixture mounted on the underside of a joist, across them and then up towards the ceiling and then turn 90 so you're parallel along a joist. The "easy" (math wise) way is to do an offset before the 90. But I try to save myself the extra bend and do a single kick before the 90 instead of both bends in the offset.
Go back to your trig tables. You are, as you suggest, bending one half of an offset. If you want the pipe to wind up running along the center of the side of a 2 x 8 joist, for example, you can measure back 8" from the far side of the 90 and kick the pipe 30[SUP]o[/SUP]. I would just make sure the starting leg odf the 90 was longer than I needed and cut it to fit, but you can use the trig tables to figure out the take-up if you want to.
 
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Old 05-11-13, 08:57 PM
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If you want the pipe to wind up running along the center of the side of a 2 x 8 joist, for example, you can measure back 8" from the far side of the 90 and kick the pipe 30o
See that's just it though, I don't think that math works out. Because of bend radius it takes some inches to get to 30, some 'time to get going' on the 2.0 constant. In a normal offset you don't notice it because the curve going out cancels out the curve going in. I think you'd either need to make a calc based on radius and angle or just waste some pipe finding numbers empirically?
 
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Old 05-11-13, 09:17 PM
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I have no idea what you just said. I just bend the 90 an inch or two long and cut to fit. Of course each of us is shooting for 800 to 1,000 feet, connected and secured, in an 8 hour day. We usually beat that, unless it's a lot of tricky short runs.

As I said, you can use trig to learn the take-up for the bend you're doing and add exactly that amount to the first leg of the 90. I've done it, just not often.
 
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Old 05-11-13, 11:02 PM
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I call it bending by braille.
Good one Tolyn


Hey.....practice makes perfect. Plus you pick up some tips and a few pointers along the way and it makes it that much easier.
 
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