Weld or buy new?(brake pedal)

Ok I have this what I think is a cast steel(maybe forged)brake pedal that was a little to long.I shortened it a little so that it wouldnt go through the firewall.I was planning on migging it,and from the pictures I have doweled it with two rollpins to give it that extra shear strength after I finish the weld.Am I being over cautious thinking that maybe I should go to a non welded flame cut shorter version.

 

Should have been a forged part, weld it and use it, providing you know how to make a good weld. If you have doubts about your welding ability, take it to someone with whom you have more confidence about welding it. Gene

 

Weld it up with proper penetration. If it makes you sleep better at night, add a gusset on either side of the welded joint.

 

V it and Tig it with silicon bronze rod. Should be fine!

 

I think the dowels make it weaker than a chamfered weld butt joint. Those dowels may not be a problem with the forces needed, but the dowels can't really help with shear, on that type of joint.

 

Thanks guys,I am capable of a good weld.Am interested to know why you would Tig though as I was going to mig but can do either.If it was just a plain old mild steel pedal I wouldn't have hesitated.Thanks Roger

 

welding will be fine. assuming you can lay a bead with good penetration.

 

Forget the silly con bronze and all that other stuff. Lose the dowel pins, that would just weaken it.

V the pieces more and tack together with a Tig. Leave a gap so you can get a full peneration weld.

Weld with ER70S-2 and when you are done smoothly blend the weld into the pedal arm with an 80 grit flapper disc on the grinder.

It will be as strong as you will ever need it to be.

 

I'd probably use a dye penetrant like Spot Check to look for crackers in and adjacent to the weld, and the rest of the pedal while I was at it.
I used my Lincoln AC-225 to successfully magnetize some 1.25 inch shafts for Magna Glo inspection. That's even better better than dye pen inspection.

 

When shortening a peddle like that, one should shorten it from the top down and not the middle. Right now you have grain pattern and high leverage forces in the middle of the peddle that you are asking the weld to hold. If you had just "topped" the peddle the leverage force is reduced, grain is not interupted,and just dealing with a mild shear weld, then add a gusset to the corner if you are worried.

 

Rodger That ! Not building a Spaceship

 

When I did mine, I made the cut diagonal. This way I had almost twice the length of weld.

J.

 

Very good point,I should have thought about that.I did it down lower so that I would have room for a couple of 1/8"dowel pins and still get good weld penetration.Do like your idea better though,especially by adding a little gusset in the corner.Live and Learn!Thanks Roger

 

For the umpteenth time, no dowel pins !!

 

There are alot of welding rods you can use but I have had good results with cast steel.

 

Cast steel is just that, steel that has been cast rather than rolled.

The ER70S-2 Tig wire is what we use on A106 mild low carbon steel piping for high pressure piping, an application where you will never see silicon bronze.

For general low carbon steel Tig welding ER70S-2 is still your best choice.

 

Well if we were welding high pressure pipe I would agree. I have found that when welding older materials and not always being 100% sure of what you are working with it is more forgiving. If you know it is low carbon steel then your choise is correct. Oh and we do agree on not using dowl pins. It is not oak

 

^^ This!