How to remove tight parts without wrench teeth mark?

Old 03-06-22, 01:56 AM
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How to remove tight parts without wrench teeth mark?

I'm disassembling a chair to return for refund and need to remove a hydraulic piston from a "multi-tilt" mechanism. They are stuck together by friction

According to the manufacturer's instruction, I'm to twist the hydraulic piston with a pipe wrench to remove it. This may leave some teeth marks on the piston which may cause them to deduct some fees for damage. If I'm unlucky, the first attempt may slip and leave gouge marks which is even worse.

Are there gentler methods I can try first?

manufacturer's instruction:
Old 03-06-22, 04:23 AM
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You need to wrap the piston rid with a piece of leather or a block9s) of wood with small groove to protect the finish. I'd also start with a set of vise grips, pipe wrench works with wedging action, vs vise grips with friction/pressure.
Old 03-06-22, 04:39 AM
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You can try a strap wrench. I also keep a scrap of heavy leather on hand. It is great for protecting surfaces when grabbing them with a wrench. Leather works great because it can provide some grip where a rag tends to slip.
Old 03-06-22, 05:18 AM
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Be sure to clean the area where you grab the piston.
Those pistons often have manufacturing oil on then.

If you do not have leather a couple of those har opening rubber sheets should work.
Old 03-06-22, 06:22 AM
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I keep hang on to bicycle inner tubes for this application. You get the idea- put a layer of something, even an old belt, between the jaws and the object. Good luck with it!

Dave O
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