Rutlands one hand clamps marking wood

[the great waldo]

I have just clamped up some Honduras Mahogany with some Rutlands one hand clamps that I bought a few years ago (red plastic sides with a black kind of rubber material on the faces) and the clamps are leaving what seems to be an oily mark on the wood. Has any one had any similar experiences with these clamps ? I tried to wash the marks out with Acetone but it didn't seem to work. Does anyone have any ideas? The clamps work great otherwise!!
Cheers
Andrew

 

[charlee19]

The clamps probably contain silicone in the plastic, acetone won't move the stain, u will have to sand out, glue some leather or softwood to the clamp areas.

 

[Doug B]

I had exactly the same with some Rutlands clamps many years ago, a chap who I worked for at the time was in the conveyer belt industry & told me it was because they used reconstituted rubber on the clamps, the way to reconstitute it was to add oil, unfortunately under pressure this added oil comes out. I don’t know if it’s 100 percent accurate but it made sense & the marks we’re certainly a blighter to get off.

 

[Oscar43634]

I recently got this with my Irwin quick grip clamps, had to sand the marks out.

 

[the great waldo]

Thanks for all the replies. I managed to get the marks out by rubbing with a cloth with some Methylenchlorid - Dicchlormethane (thats the German name for it on the bottle. It's used for model plastic kits as glue) A quick rub and the marks have gone. I hope it helps?? I sent Rutlands a message and they sent me a reply saying I should use a caul!! Not a very inspiring reply , but I suppose that's what you get these days.
Cheers
Andrew

 

[Lons]

I got into the habit years ago of using thin packers of ply, mdf and scrap white pvc on every clamp, plastic ends or not. I have a box full, it's become second nature and doesn't mark or bruise the work.

 

[Bingy man]

I have the same problem with the same clamps. I use plywood shims if i don’t want to leave any marks. Always wondered why it happened as were supposed to be none marring..

 

[Jason Wheeler]

had similar issue with certain woods - I used some 1mm self adhesive backed cork on the clamp faces

 

[Fergie 307]

Even cardboard works, just cut up an old cornflakes box or whatever. Make sure it's the plain rather than the printed side against the wood!

 

[Trafalgar]

Yes, this happens when the clamp pads aren't plain rubber. Whatever they make them out of now, bleeds some sort of oil onto the wood. I have had some penetrate so deep it could not be sanded or scraped out without leaving a depressed mark on the wood. You'll need to interpose something between the pads and the wood, which renders the pad themselves more or less useless.

 

[thetyreman]

leather works well, I can get offcuts for free from an upholsterer near me, glue it on with epoxy, it also improves the grip and prevents slipping.