Bending help

[spike7638]

Wow...a ton of good points here. I'm making 22 of these, and I need to get them done more or less today, so making up a bending jig (or a die to "press" the piece into) isn't really feasible. Yes, the two end tabs need to be coplanar; that can be achieved by slightly adjusting the two bends that look like 30 and 60 degrees. Regarding "could be done in a vise", the person whose ideas I'm copying bent hers with a sledgehammer in a vise, so that gives you some picture of how fine the tolerances are.

Thanks for the bend-allowance chart --- that'll help me get things mostly right.

--John

 

[tq60]

You first make ONE.

Or, if once a bend is made it cannot go back, make a couple "masters"

You place the already bent master next to the to be bent part and bend until it matches.

Write master on the master with a sharpie.

You can place several in the brake at same time as well.

Sent from my SM-G781V using Tapatalk

 

[spike7638]

Thanks everyone; the results came out pretty well. Are they perfectly identical? No. Close enough? Absolutely. Marking the degree-of-bend with a piece of masking tape on the wall behind the bender turned out to be a great idea, as did the "bend some scrap around the sharp tip of the finger to make a softer form" idea. Some of the 90-degree bends at the top of the photo below were a bit more than 90 degrees, but screwing the assembly in place will fix that right up.

 

[finsruskw]

I cranked out about 40 of these a year ago using a homemade die.
Bumper jack trunk tie down kits, 57-59 Chrysler
Used 1 x .125 flat steel bar
Just takes a little trial and error.
Yours turned out great!
What are they for?

 

[brino]

Thanks everyone; the results came out pretty well.

They look great!

I cranked out about 40 of these a year ago using a homemade die.

I think your pictures were the ones I was looking for!

Brian

 

[RJSakowski]

This is a good plan. I would recommend some sort of marker, pencil, etc and not going to scribed lines — I’ve had pieces of bar start to crack right on that scribed line as I was bending them. Not something you want to think about on a sailboat mast….

A light scribe line on a blued surface needn't be deeper than a thou or two. If a stress creck is a concern, the scribe line can be sanded out after the bend is made.

 

[francist]

A light scribe line on a blued surface needn't be deeper than a thou or two. If a stress creck is a concern, the scribe line can be sanded out after the bend is made.

Agreed. I have had bends fail right on the scribed line during the bending process though, so that’s why I have abandoned the process entirely. I have taken to using a small punch mark on hot work where I might otherwise lose a sharpie or soapstone line.

Im glad the OP’s project came out so well, that’s the main goal.

 

[spike7638]

I cranked out about 40 of these a year ago using a homemade die.
Bumper jack trunk tie down kits, 57-59 Chrysler
Used 1 x .125 flat steel bar
Just takes a little trial and error.
Yours turned out great!
What are they for?

They're for climbing up a sailboat mast. The small tab near the 90-degree bend goes at the bottom of each step; the small tab at the other end goes at the top. This gives you a step that not only supports your foot, it also keeps your foot from sliding off the end that's away from the mast, which is nice.

 

[RJSakowski]

Agreed. I have had bends fail right on the scribed line during the bending process though, so that’s why I have abandoned the process entirely. I have taken to using a small punch mark on hot work where I might otherwise lose a sharpie or soapstone line.

Im glad the OP’s project came out so well, that’s the main goal.

I have seen cracks propagate from scratches/scribe lines on the outside of a bend. I always scribe my line on the inside where the metal is in compression. Good idea about the punch marks though.