Speedmaster 5mm- 3/16 flex hex coupler problems ?

[Andris Golts]

Hi all. I am having an issue once i tighten the coupler and after several runs i back the nut off the coupler i really have to pull hard to remove the 3/16 flex shaft . I always solder the last 1/2 inch off the shaft and bevel the end of the shaft the collet to flex shaft alignment is perfect i even chucked the end of the shaft that goes in the collet in the lathe and ran a emery cloth across the end in case of a burr i slid the shaft in and out of the collet 10 times no problem once i tightened the coupler nut and backed the nut off again same problem i really had to pull hard to pull the shaft out again and i could not see no problem with the inside of the collet either ! WHAT ELSE COULD BE CAUSING THIS PROBLEM ?In my 46 yrs of r/c boating i have used H&M Aeromarine and Octura couplers and never had this kind of problem .Regards Andris Golts

[CJPB32]

I'm guessing the split "legs" (if that's the correct term? or jaws?) of the collet are deforming and staying clamped around the flex shaft. The collet should flex open again after loosening the coupler nut. Maybe a material problem.... its being clamped/flexed past its elastic limit.

[Andris Golts]

CJPB32 Thanks for your reply. Regards Andris Golts.

[jingalls007]

Speedmaster, IMO, make the tightest collet on the market. Their 1/4? cables can be a challenge to get in and back out even without tightening down. The collet inserts are sharp so that they grasp firmly with good precision. TFL, LMT, and a few others I use don?t grab like speedmaster collets; Speedmaster is my favorite.