Straightening or bending metal

[bota7800]

Are there any guidelines about how to bend metal? What temperature do you preheat to?

Examples-
1. My new-to-me rock rake has a couple bent tines. Can I heat and bend them back to somewhat the original shape.

2. The blades on my manure spreader need to be straightened. I can lever these to bend them back but that work hardens them. Can I preheat the metal?

These are my current needs but I frequently come across this and I don't know what I am doing so I would like more information.

Thanks all.

 

[jmfox]

I do it with hammers and wood to avoid hammer marks. It's a Zen experience, unless of course you know what you're doing. Strange, yet the results always amaze my friends. If you have an eye for symmetry and level, try it.

jmf

 

[MJPetersen]

Rake tines should be made of spring steel. It is shaped and then tempered. So if you heat it you will destroy the temper. If you try to straighten them without heating they will probably fracture. The best thing to do with rake tines if you are not prepared to re-temper them is to replace them.

Sorry I do not know at what temp or the method that you should use to re-temper them either.

Mike

 

[bota7800]

Thanks. I have done OK using hammer and dolly when taking the dents out of a horse trailer but that is thinner metal. I thought with the blades I would need to heat them but I guess I will try carefully straightening them cold. I know that the trailer repair shop I used to weld some parts used heat when they straightened a bent step.

Mike, that is about what I thought about spring steel but wanted some input.

 

[ray66v]

The rule I was always taught was don't heat treated steel, and if you do heat it, use as little heat as possible, and let it cool on its own.
Try it on a tine or two, and see what happens. You can always replace them.

 

[bota7800]

The rule I was always taught was don't heat treated steel, and if you do heat it, use as little heat as possible, and let it cool on its own.
Try it on a tine or two, and see what happens. You can always replace them.

I will try it cold first. Makes me wish I had bought the Pequea- it has bolted on tines.

Is there a way to tell if steel has been heat-treated or do you just assume it has been in an application like this?

 

[MJPetersen]

Makes me wish I had bought the Pequea- it has bolted on tines.

Wait, are you saying that the tines on your rake are welded on? If they are then either they are not treated, or they have already been damaged by the welding.

Mike

 

[wushaw]

I would hit it with a rose bud tip on the oxy/acet rig and bend them how you want.

If they are heat treated then bending them back may break them without heat.

You can always quench them in oil after heating them, that'll put a little temper back in the heated part.

 

[bota7800]

I would hit it with a rose bud tip on the oxy/acet rig and bend them how you want.

If they are heat treated then bending them back may break them without heat.

You can always quench them in oil after heating them, that'll put a little temper back in the heated part.

That's what I love about these forums- ask a question and get diametrically opposed recommendations .

I have been thinking about getting an O/A setup anyway so I may try it. It would be nice to know what temp range to heat to.

 

[ray66v]

The only way to know for sure, on your rake, short of finding someone whom has fixed one, is going to be to try it. Find out what works, and then you will know.

I would heat it only where it appears to have bent, and then, heat only enough to be able to bend it back. This is the safest approach. If it appears to soften up the area you heated, i.e. bends very easily there again, you could run a couple of beads of weld over it to stiffen it back up.