Marks left by clamps

[David Romano]

I use the Jorgensen adjustable clamps, the orange ones with the urethane like pads over the cast iron part. They leave behind a "wet spot" after the clamp is removed. Usually this is not a problem because I have to sand there anyway. It seems to soak in pretty far. What is it? Maybe the plastic is decomposing under the heavy compression I'm guessing. Is there a way of removing it w/o sanding? Tried mineral spirits, not quite sure it worked well enough.

thanks

David

[Mike Jones NM]

Depending on the amount of space I have to work with I seldom clamp directly to my piece I'm working on for this very reason. I keep some thin strips of hard wood laying around and use it as a buffer between the clamp and the work piece.

[Bill Huber]

I use the Jorgensen adjustable clamps, the orange ones with the urethane like pads over the cast iron part. They leave behind a "wet spot" after the clamp is removed. Usually this is not a problem because I have to sand there anyway. It seems to soak in pretty far. What is it? Maybe the plastic is decomposing under the heavy compression I'm guessing. Is there a way of removing it w/o sanding? Tried mineral spirits, not quite sure it worked well enough.

thanks

David
I had the same problem, I had to sand them out. I how have packing tape on the plastic covers of all of them plus it holds then on and they don't fall off when I take them off and go to hang them up.

[Chuck Lenz]

I do the same as Mike, I allways use a piece of wood between the clamp and the piece I'm assembleing. Especially if I'm constructing something made from a soft wood. You may be able to sand it out, but in time the crushed wood fibers will more than likely eventually pop back out and thats really frustrating to me to see on a project that I sanded, and put a finish on after clamping.

[glenn bradley]

I actually thought we finally got a response out of Adjustable Clamp Co. on this. We were supposed to here in "a couple days" and the thread went dead. I can tell you wax paper does not do the job.

I still use scraps or tape if I have to clamp onto the business surface of a piece. Mineral spirits lift some of them off but others (like if left overnight) are tough to get out even with sanding. I've used high density felt (like for furniture glides) with success on some of my clamps.

[Steven Wilson]

if you have crushed fiber problems lightly wet a very clean white cotton towel and then take a fairly hot iron over it. The indentations will steam out and you can lightly sand off the resulting marks.

[Bob Barkto]

I have experienced the same problem. Only on the imported M.I.C. Jorgies.

The pads are very soft, I suspect the residue is plasticizer leaching out.
I cleaned them with some alcohol and it went away for a day or so. Now it's back.

I don't have that problem with the pads they sell to retrofit the light duty and pipe clamps. It's a slightly harder/stiffer plastic.

[jim gossage]

i have the same problem with most of my clamps that have plastic pads. painters tape works well. another solution is to take scrap wood and cut it into "pads", then press on 1" wide magnetic tape (one side has adhesive). the magnetic side will hold the wooden pads to the clamps after you remove the plastic pads.

[Chuck Lenz]

Thats a good tip Steven, but if I can avoid the problem first, then I don't have to go through extra steps to correct it.

[David Romano]

Those were some good suggestions, I figured it is a common problem. I haven't experienced the wood popping back out, maybe the wood is hard enough to prevent the fibers from crushing. I'll probably try the packing tape idea. The wood blocks are probably the best, but as you know, anything slows down the glue-up/clamping process raises blood pressure.

Thanks everyone

David

[Jamie Buxton]

There's two issues in this thread. The OP's problem is something leaching out of the plastic pads and staining the wood. I've seen that issue too, and it sure is irksome. I washed mine with lacquer thinner, and that has seemed to fix the problem.

[Steve Clardy]

I've removed most of my pads, and put leather on like I did on my older clamps, before they even had the cushion pads on them.

I just cut a small scrap of leather, and use glue to glue them on.

It will surprise you how long wood glue will hold leather on metal.

[Cliff Rohrabacher]

Use wood blocks.

If that is pain to manipulate just Epoxy pieces of pine to the clamps and toss those plastic things.

I am unsure why you'd be using so much pressure as to be wringing the polymer out like that.

[Al Willits]

Anybody try cork?
Read somewhere to lightly glue 1/8" sheet/square of cork onto the plastic.

Bought the cork, just haven't tried it yet...another project in the to long list... :)

Al....to thin for bobbers, gotta be good for something..:)

[Jim Becker]

Al, cork is one solution. Many Neanders use leather on their vices, etc., for the same purpose...'could be useful for clamping, too. Of course, not cranking the clamps too tight also helps. ;)

[Bob Barkto]

Speaking for my own experience, it wasn't excessive pressure.
The weight of the clamp alone causes the spots to appear.
This has only happened with the newer Jorgensen 3700-HD bar clamps.

The pads are much softer than any others I've ever seen.



Use wood blocks.

If that is pain to manipulate just Epoxy pieces of pine to the clamps and toss those plastic things.

I am unsure why you'd be using so much pressure as to be wringing the polymer out like that.

[Al Willits]

Thanks Jim, clamping to tight kinda goes with cutting to short though...hard to realize you did until to late... :)

More of that learning curve again....:D :D

Al

[Steve Clardy]

Use wood blocks.

If that is pain to manipulate just Epoxy pieces of pine to the clamps and toss those plastic things.

I am unsure why you'd be using so much pressure as to be wringing the polymer out like that.

These pads are pretty soft Cliff.