How do (or should) the PTC fittings work?

[Hansen]

Hi all

I noticed that I can move the bowden tube in the PTC fittings (both ends) a few millimeters back and forth. It is like the fittings do not grab the tube properly. Also, it seems it has no effect to press the plastic thingy, when the tube is to removed. Despite the "back and forth" movement, it is still very hard to remove the tube from the fittings. Do your fittings allow the bowden tube to move back and forth?

BR
Hansen

[Eaglezsoar]

Hi all

I noticed that I can move the bowden tube in the PTC fittings (both ends) a few millimeters back and forth. It is like the fittings do not grab the tube properly. Also, it seems it has no effect to press the plastic thingy, when the tube is to removed. Despite the "back and forth" movement, it is still very hard to remove the tube from the fittings. Do your fittings allow the bowden tube to move back and forth?

BR
Hansen

What you have described is normal. Someone on this forum printed some rings that fit between the body of the PTC and the push down thingy to keep it from going down.
Supposed to keep the tube from moving. I have found that small hitch clips work also. Some PTC fittings work better then others but when you push the thingy down I also push on the
tube slightly and then pull the tube from the PTC. Some are just ornery and don't want to release the tube.

[Hansen]

It was actually Steve123's thread (here: http://forum.seemecnc.com/viewtopic.php ... &p=45531&j bhilit=ptfe#p45531) that made me look into the fittings, and what I don't understand is that even if I mount these clips (so the plastic thingy can't move), the tube can still move a few millimeters. Is that also OK?

[Eaglezsoar]

It was actually Steve123's thread (here: http://forum.seemecnc.com/viewtopic.php ... &p=45531&j bhilit=ptfe#p45531) that made me look into the fittings, and what I don't understand is that even if I mount these clips (so the plastic thingy can't move), the tube can still move a few millimeters. Is that also OK?

Yes, the tube will still move a small amount. The PTC connectors that I have used all allow slight movement of the tube.

[McSlappy]

I also noticed it depends on the PTC fitting. One of my stock ones was moving slightly so I swapped it for another one I had and the movement is gone.

[Hansen]

In my mind movement of the bowden cable decreases the effect of retractions, so these movements can't be any good. I just ordered a pair of all-metal fittings. Hopefully, these will be better...