Loose retention knobs....

85 ft/lb of torque ought to do it. Belleville springs suck that puppy up inside the spindle. How much pull you got?

DT:

We had one "rattle" 5 or so years ago. It didn't do much damage as far as we could tell. The outer edge of the spindle is the part that seemed be making contact with the toolholder. So we smoothed out the spindle edge and stoned and scotch brighted the toolholder and everything seems to have been working fine since then.

We change retention knobs all the time between the Haas and Fadals (since the Haas uses a much longer retention knob). What we did after the "rattle" was make a little tightening fixture. Well, fixture is glorifying it a little, it's just a piece of steel angle about 2" X 2" X 2" with a slot milled in it that fits the flats of the retention knob. The angle is screwed to the edge of our tooling table. We just put the toolholder knob side down in the "fixture" slot, and hand tighten it real good. Hand tightening has worked so far, but sometimes if the job is going to be a long running one, we use the ER-32 spanner wrench to tighten the knobs on tools that are going to be subjected to extreme force/vibration.

Hey, could this be considered a setup tip? Somebody ought to archive this puppy on a blog or something. :)

I just carefully hold the wrench onto the stud by hand and then whack the wrench end sharply against the workbench top--never had one come loose yet.

Somethings making them come loose. Make sure your using the right ones. Also...DONT overtighten the retention knobs, its makes the back of the taper swell. Tears up your machine according to a hass article I read. As far as loctight...use just one tiny drop on one point of a thread. Just enough to hold it if your machine is rattling it loose.

Why? Blue loctite breaks free.

Wes

Loose retention knobs = essentially being a (hack) machining asshole. goodgawd....

But with some lame excuses.

Like, my cat40 tightening fixture makes it fairly awkward to tighten these, and the narrow flat makes it difficult to grab with my itty-bitty shitty adjustable, AND, since everything is goddammed hardened to one degree or another, you cain't feel anything "sink" down, which threw me off.

So now I make the effort (big effort, eh?) to go thru the nec contortions with the cat 40 holder, and use a crapsman 3/4 open end wrench instead of the wobbly adjustable, and put on about 30 lb-ft of torque -- which is about

29.75 more than before. 85 lb-ft seems a bit much, but if there is consensus on that, hey, I'll just do more pushups until I can manage. :) Or get a 4 ft wrench. :) :)

"Problem" essentially solved.

Screw it in as deep as you can and if it's still not tight enough then finish off by whacking it.

Never suggest DT Whack anything!!

What are you thinking?