bent shear blade

[mog5858]

well i just go this brown and boggs stomp shear home and stared to take it apart to clean it up. now i found out that the bottum blade is way bent. anyone got any good idea on how to stratin the blade? can i just heat it up and ben it back? i have a 100 ton press should i do it cold any help would be nice thanks i would say it's 2 high by 1/2 thick

[mog5858]

no one has and help?

[HuFlungDung]

It's been my experience, that sometimes you can bend a hardened steel piece in one direction, a certain distance. But bending it back cold typically results in instant fracture at some unknown amount of pressure. It is dangerous, and probably a wasted effort if it breaks the blade.

I don't know anything about shears, but does the bend hurt anything? Don't some shears have a guillotine style blade with a progressive cut? Maybe you can use it? Is there not some sort of 'back-up' bar to help support the load the blade takes? Why is it bent?

If you do bend it, I think you'd need to do it at a very elevated temperature. If the blade is some carbon alloy, then you'd essentially need to anneal it where you intend to bend it, and then you'd need to have the whole thing heat treated and re-hardened and tempered.

You might make your own, just buy a piece of tool steel, drill the holes and get it hardened. Might be less trouble in the long run.

[mog5858]

thanks for the info i bent it cold. everything work out ok now i just need to get a good grind on it and do a little sand blasting and i should have a nice little shear. now i just need to figger out how i going to grind my blades as i dont have a grinder to it on and know one in town dose eather. thinking of a 5" grinder held sold then bolt to the boring mill. good idea or bad?

[Konrad]

Hmn..can't be very good steel,.. most likely not tool steel.
I was going to say to put it back the way it was,....must have been under tension.
Can you take it to a grinding shop, or somebody who does knife blades, like Zamboni
ice blades & paper knifes can do shear blades also, it seems most major city has this
service, in Edmonton there is at least two I know of.

[mog5858]

i will look in to it but i live 2 1/2 hours from a city and i really hoping not to have to pay big bucks. i might take to work and do a rockwell test to see if they would hold a edge and then go from there cus your probably right that they are soft when they did not brake when bent back. thanks for the good idea on the zamboin they got realy long blads.