Loose retention knobs....

Awl--
What's a good fix?
Ahm thinkin nylon washer, but not sure if the .030 or so in height change will affect the grabbing, etc.
Only other solution would seem to be loctite or equiv.
Iny idears?
Inyone have a cat 40 rattle in the spindle? What's the prognosis ito of spindle accuracy/wear, etc.?
Goddamm retention knobs are not cheap, either. I get cheapies for like $12 ea (or *used to*), but sheeit, 5 of those and you got another cheapie tool holder!
Sheeit, 12 pairs of Maxima headlight sets, and you got a new car!!!!!
Oh, cuz I hear it comin: My *sandvik* stuff comes loose as well, a'ight?
--
PV'd



Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
really don't want to loctite em..
throw some anti-seize on em and wrench em down tight.. bring that good ol breakerbar out and put ur back into it ;) DrollTroll wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Why? Blue loctite breaks free.
Wes
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

85 ft/lb of torque ought to do it. Belleville springs suck that puppy up inside the spindle. How much pull you got?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
DrollTroll wrote:

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. :)
--
BottleBob
http://home.earthlink.net/~bottlbob
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

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.
--


Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

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.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

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.
--
PV'd








>
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

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


Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Never suggest DT Whack anything!!
What are you thinking?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.