[warrenb]

Hello Y'all,

New problem on a 2016 VMC 2003 model. For a while the tool changer became worse and worse for releasing tools until finally it refused to release tool all together. I assumed a bad drawbar so ordered a new rebuild kit (with springs) and got everything nice and clean and installed the recommended springs in to this non-locking spindle. The old drawbar was in pretty bad shape so I hoped this would fix the issues. Still I have to same problem. The draw bar is not pushing down far enough. I have proper air pressure and everything is assembled correctly. Is there something further up the line I may be missing like the pneumatic valves or somewhere an airline may be pinched preventing enough pressure? Has anyone measured the drawbar force or know what it should be? Too many bellevues maybe? Anyone have this issue in the past? I'm stumped. Thanks

[Tedger]

There is rectangular aluminum plate that is attached to the pin that pushes down on the drawbar. The Plate is actually the moving part (Piston) of the air cyclinder. I have had these crack and leak air during a tool change, Thus not pushing hard enough on the drawbar. I would look there next.

[warrenb]

There is rectangular aluminum plate that is attached to the pin that pushes down on the drawbar. The Plate is actually the moving part (Piston) of the air cyclinder. I have had these crack and leak air during a tool change, Thus not pushing hard enough on the drawbar. I would look there next.

Thanks Tedger,

Been looking at all the attached parts including the plate. Nothing obvious but I'm going to replace the gasket around it and the pushrod as well. Hopefully it works. Since it is off I will pull al couple more bellevues just to test. I have an idle machine so I'm about to start making a Frankenstein FADAL just to get this one running for some parts I need yesterday.
W

[Tedger]

See attached for Bellville info

[warrenb]

Solved... I Hope
I believe the problem is from burrs that were in the retaining ball pockets and along the bell. The balls would stick in side the drawbar bell and wouldn't release, or accept the tool posts. I took everything apart, cleaned it, polished the pockets, added a chamfer to the drawbar bell and all seems to be working now. I also took out 2 bellevue washers (from the recommended) for the time being while I run tests and hope to 'break in' the drawbar assembly. Note... If ordering a new draw bar assembly make sure the company you buy them from checks the finish work on the parts. This has been a frustrating problem to chase down.