A Bender for Arch Bars
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- Location: Pittsburgh, PA
Re: A Bender for Arch Bars
That is a nice design! Sure beats the way I did the arch bars for my shay!
Thanks for sharing the drawings!
Thanks for sharing the drawings!
- Greg_Lewis
- Posts: 3014
- Joined: Wed Jan 15, 2003 2:44 pm
- Location: Fresno, CA
Re: A Bender for Arch Bars
A slight cut into the bar at the bend point with a hacksaw will insure that the bend happens at the exact spot you want, and will give a nice sharp bend. Such a cut is unlikely to compromise the strength of the bar considering the forces applied to the truck, but you can fill it in with silver solder, which is what I've done.
Greg Lewis, Prop.
Eyeball Engineering — Home of the dull toolbit.
Our motto: "That looks about right."
Celebrating 35 years of turning perfectly good metal into bits of useless scrap.
Eyeball Engineering — Home of the dull toolbit.
Our motto: "That looks about right."
Celebrating 35 years of turning perfectly good metal into bits of useless scrap.
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- Posts: 983
- Joined: Wed Jun 27, 2012 5:24 pm
- Location: Marietta, Georgia
Re: A Bender for Arch Bars
I agree! The shop press bent the bars easily but some of mine got a little off so required some banging and prying to assemble. I’ll definitely give this idea a go when I start making rolling stock archbars.Brian Hilgert wrote:That is a nice design! Sure beats the way I did the arch bars for my shay!
Thanks for sharing the drawings!
-Tristan
Projects
-2.5" scale Class A 20 Ton Shay
Steam Siphon: https://www.shapeways.com/shops/leavitt ... tive-works
Projects
-2.5" scale Class A 20 Ton Shay
Steam Siphon: https://www.shapeways.com/shops/leavitt ... tive-works
Re: A Bender for Arch Bars
You might think about adding a set screw on the die block. I have found that no matter how tight the fit between the two blocks the force of bending the arch bar can make it slide from its original position giving inconsistent bends.
Just a thought.
Jeff Smith
Just a thought.
Jeff Smith
Re: A Bender for Arch Bars
Center the die block and bend two angles at the same time...jeffsmith wrote:You might think about adding a set screw on the die block. I have found that no matter how tight the fit between the two blocks the force of bending the arch bar can make it slide from its original position giving inconsistent bends.
Just a thought.
Jeff Smith
Re: A Bender for Arch Bars
I discovered this too. As you say when trying to bend the 1/4" x 5/8" bars it tends to move no matter how tight the bolts.You might think about adding a set screw on the die block. I have found that no matter how tight the fit between the two blocks the force of bending the arch bar can make it slide from its original position giving inconsistent bends.
Just a thought
My thought is to cut a rabbit about .0625 deep for the die block to sit down into the plate giving it a stop to go against.
I will try it this weekend.
Charlie Pipes
Mid-South Live Steamers
Current Projects:
Scratch Built 3 3/4 scale 0-4-4 Forney
Little Engines American
20 Ton Shay (Castings and Plans Purchased for future)
Mid-South Live Steamers
Current Projects:
Scratch Built 3 3/4 scale 0-4-4 Forney
Little Engines American
20 Ton Shay (Castings and Plans Purchased for future)
Re: A Bender for Arch Bars
I am thinking along these lines
Charlie Pipes
Mid-South Live Steamers
Current Projects:
Scratch Built 3 3/4 scale 0-4-4 Forney
Little Engines American
20 Ton Shay (Castings and Plans Purchased for future)
Mid-South Live Steamers
Current Projects:
Scratch Built 3 3/4 scale 0-4-4 Forney
Little Engines American
20 Ton Shay (Castings and Plans Purchased for future)
Re: A Bender for Arch Bars
Charlie,
Since you have drilled the arch bar blank material for the bolster pedistals, use the holes on dowel pins or bolts through the clamp blocks to assure the bends are the same distance from each hole when you turn the blank over to do the other end. Add a hole through the anchor blocks and slide a dowel pin or bolt through them with the blank between them. You may need to relocate the outer bolt holding the bend block in its seat slot.
Down and dirty 'out of perspective' sketch:
Since you have drilled the arch bar blank material for the bolster pedistals, use the holes on dowel pins or bolts through the clamp blocks to assure the bends are the same distance from each hole when you turn the blank over to do the other end. Add a hole through the anchor blocks and slide a dowel pin or bolt through them with the blank between them. You may need to relocate the outer bolt holding the bend block in its seat slot.
Down and dirty 'out of perspective' sketch:
Re: A Bender for Arch Bars
This is an interesting approach.
My drawings are a little misrepresenting as I am planning on using the fixtures to drill the holes after bending.
You method would definitely have merit.
I did this tonight before running off to church. it is a stop guide attempt. I also swung by the steel yard to get a piece heavy wall tubing to make a cheater bar for the bending arm.
Out of curiosity. is your drawing in Solidworks?
My drawings are a little misrepresenting as I am planning on using the fixtures to drill the holes after bending.
You method would definitely have merit.
I did this tonight before running off to church. it is a stop guide attempt. I also swung by the steel yard to get a piece heavy wall tubing to make a cheater bar for the bending arm.
Out of curiosity. is your drawing in Solidworks?
Charlie Pipes
Mid-South Live Steamers
Current Projects:
Scratch Built 3 3/4 scale 0-4-4 Forney
Little Engines American
20 Ton Shay (Castings and Plans Purchased for future)
Mid-South Live Steamers
Current Projects:
Scratch Built 3 3/4 scale 0-4-4 Forney
Little Engines American
20 Ton Shay (Castings and Plans Purchased for future)
Re: A Bender for Arch Bars
Keycreator - it doesn't like being converted to a jpg. Stops are a good thing.
Re: A Bender for Arch Bars
Charlie - another method: http://www.nelsonslocomotive.com/Small% ... ckBars.htm