Problem detaching split column of tripod

[Searcher]

I seem to have tighten the split column of tripod too tightly and is now unable to unscrew them apart. Does anyone know of a good way to loosen it without destroying the column?

 

[GavinTing]

Hmm.. Use something with friction.. Like a rubber mat, masking tape etc.. Or wrap with a cloth, and use a pair of pliers..

 

[Searcher]

pliers won't crush the column after wrapping with cloth? I have been thinking about using pliers but afraid I will crush the column. But cloth has no grip on the smooth smooth tube, wondering if the pliers will grip or not after being cushioned by the cloth.

 

[Leong23]

Maybe can help by spraying some WD40

 

[denniskee]

what is the brand and model of the tripod? easier to imagine the problem if we know that.

 

[Searcher]

Velbon Carmange 640, the centre split column. Haha I think I manage to turn the bottom long column too tight. I manage to detach it before, think when I screw back I screw it back on too tightly or something.