Straightening G Clamps

[Turbo]

I bought these last week.

The top one is a 6" taparia. Never came across these before but it is heavy built & the only one that's still straight!

The middle one is a made in england 8" record. It has a a slight twist in it so that the clamping faces don't meet. What are they made from & can they be straightened? Do I use heat on it?

The bottom is a 10" unbranded one, just has 'malleable' written on it. The frame is bent both ways & has seen some abuse. Any advice on straightening this?

 

[oilcooled :)]

I'd straighten them in a vice using a combination of big stilsons shifters and big hammer. Personally I wouldn't b on for heating them up. Should go cold with brute force and ignorance .

 

[Richard.]

You can pull em back with traditional force. Held in a vice and pulled about or under a press etc but TBH once they are bent out of shape they pretty much always go back to been bent out of shape.

 

[Wendelspanswick]

I bought a job lot of Record clamps cheap at auction that had been abused so I used localised heat on the frames to straighten them and they have been fine since, this was about 20 years ago.

 

[Gritineye]

Most cramps get bent when things go wrong, like something collapsing or getting knocked over, they shouldn't bend again if used with hand power only.

 

[Exuptoy]

The problem lies with people not using them as intended.
They're for clamping to holding stuff in place not for forcing the screw to do something never intended with a big shifter or hammer on the T-bar to tighten it up!

At the end of the day they're still only mild steel so should be workable to get them back as intended.

 

[Shox Dr]

Top and bottom are joiners cramps; sliding bar handle
The middle is an engineers; wing nut

I cant remember what differs between the two.

I wouldnt try and bend them back with no heat, they can snap like twigs.

 

[Yoda]

I've heated and straightened G clamps in the past and thought nothing of it until one day while welding a stock car chassis up it shattered, just missing my head on the way past. Every time i damage a G clamp now i replace it.

 

[The_Yellow_Ardvark]

If they are cheep cast ones, junk em. bin them scrap them.
Not worth it, as said by @Yoda they will fail again.

If they are the machined ones and they are bent, what did you do to bend them, or are they cheep again.

They are not worth it.
go along to a good Boot, good second hand tool shop or the bay of evil. Get some decent ones.

G Clamps are only there to hold in place. key word "Hold" never to move into place.
You want that, get some decent Carver clamps (any one got spares?)

 

[BarrieJ]

Bought some in similar condition from boot sales in the past, straightened them cold; vice and copper faced mallet and a big one: hot, gas and a stillson. All have been OK but I don't abuse my tools.
There are cheap Chinese cast iron ones about, in which case it's doubtful they ever got as far as bending.

 

[jordan1]

If they are decent quality ones and not too badly out of line just straighten them and use them as intended, you should be fine.

 

[Rig Pig]

Keep an eye open for Carver rack clamps, they are brilliant, I scored a couple at a car boot.

 

[Kent]

Most cramps get bent when things go wrong, like something collapsing or getting knocked over, they shouldn't bend again if used with hand power only.

Or tying ropes to them as a safety device installing beams by hand

 

[Turbo]

Thanks for all the replies & advice!

I have 5 carver clamps which I use for steelwork & when something needs 'pressed together'.

I have 4 x 4" record clamps. I restored these, now I'm afraid to use them in case I chip the paint!

The rest of my clamps are a mixture of F clamps & 7 unbranded g-clamps in various sizes. These are mostly used for woodwork and that's what I plan to use these new ones for so they're not going to get much abuse once straightened!