Project of the Month built by Rustkolector

Help Support Home Model Engine Machinist by donating using the link above or becoming a Supporting Member.
Home Model Engine Machinist > Building Them > Mistakes, Blunders and Boo Boos > ruined a mill spindle (maybe)

Reply
 
Thread Tools
Old 12-26-2017, 02:55 PM   #1
SE18
 
Join Date: Mar 2012
Location: N. Va.
Posts: 11
Liked 2 Times on 1 Posts

Default ruined a mill spindle (maybe)

I ruined (fretted) the spindle on my Clausing 8530 Mill. It all started when it became difficult to release my collets from the drawbar. I keep a brass hammer handy to pound the acorn nut atop the drawbar. To remedy (besides ensuring spindle clean and oiled), I didn't tighten the drawbar nut as tight as I should have, thinking I was overtightening it and contributing to the difficulty to release the collet. While milling, the collet became loose and spun around for a few seconds inside the spindle, which was long enough to produce extensive fretting inside the spindle and on the MT2 collet. Now I don't know what to do. Extensive searches on the Internet reveal no information on corrective action. One person said to use some sort of scraper on a different forum. Perhaps I don't need to do anything at all since the mill is still working? Your feedback would be great.


SE18 is offline  
 
Reply With Quote
Old 12-26-2017, 04:28 PM   #2
nautilus29
HMEM_SUPPORTER.png
 
Join Date: Jun 2017
Location: Findlay, Ohio
Posts: 63
Liked 9 Times on 7 Posts
Likes Given: 1

Default

I would blue up one of your good collets and tighten it in the mill. When you take it out see how much surface contact you have between the spindle and the collet. You may be able to get away with cleaning up any high spots if there is still enough contact to hold it securely.

I would also try putting dowel pins (or stick your end mills out of your collet a little bit) and check the runout of different collets. Up towards the collet and away from the collet if you can. This can help you decide what you want to do.

If these tests dont look too bad, and you aren't noticing extra chatter in your tools I'd say you can leave it go if this is just a hobby mill. If it gets heavy use you may want to consider getting the spindle reground, although I'm sure that is expensive.


nautilus29 is offline  
 
Reply With Quote
Old 12-26-2017, 04:43 PM   #3
SE18
 
Join Date: Mar 2012
Location: N. Va.
Posts: 11
Liked 2 Times on 1 Posts

Default

thanks; the blueing test was done and doesn't look bad; just the tip part inside the spindle so I'll just continue using it for my occasional hobby work
SE18 is offline  
 
Reply With Quote
Old 12-26-2017, 04:53 PM   #4
aonemarine
 
aonemarine's Avatar
 
Join Date: Nov 2012
Location: wilmington DE
Posts: 848
Liked 187 Times on 143 Posts
Likes Given: 29

Default

I would get an mt2 reamer and spin it lightly in the spindle to clean it up, and be checking it before and after use with a .0001" DTI.
aonemarine is offline  
RM-MN Likes This 
Reply With Quote
Old 12-26-2017, 06:41 PM   #5
Wizard69
 
Join Date: Mar 2013
Posts: 1,029
Liked 198 Times on 176 Posts

Default

You can always pull the spindle quill and take it to a grinding shop for rework. If the galling isn't to deep they may be able to clean the taper up. Otherwise you can make a new spindle. At some point almost all spindles end up needing resurfacing due to the draw in of the collets.

You can try the various remediations already described but they generally lead to a loss of precision in run out.

Another option to consider is to have the spindle ground in place. This is done on CAT style tapers but i have no idea if it can be done on a manual morse taper machine.

By the way Morse tapers are locking!! That means one properly set well be hard to release. A Morse taper collet should always require some effort to remove.
Wizard69 is offline  
 
Reply With Quote
Old 12-26-2017, 09:10 PM   #6
SE18
 
Join Date: Mar 2012
Location: N. Va.
Posts: 11
Liked 2 Times on 1 Posts

Default

thanks again, all!

AoneMarine, I'll try your method first with a finishing reamer. I'll turn it by hand.

As for the collett that spun, it shows signs of distress (circular lines). So perhaps put it in lathe chuck and using compound at angle use a finishing bit to lightly clean it up? (semper fi)

BTW, I got more help here than on 2 machine forums
SE18 is offline  
 
Reply With Quote
Old 12-27-2017, 06:49 PM   #7
SE18
 
Join Date: Mar 2012
Location: N. Va.
Posts: 11
Liked 2 Times on 1 Posts

Default

Update: I spun the collet MT2 in the lathe while holding sandpaper on it which effectively removed the galling. Ordered the MT2 finishing taper which should arrive before Feb. 7, as I used low-cost shipping


SE18 is offline  
 
Reply With Quote
Reply


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Magnetized spindle on G0704 mill RonGinger Tools 1 12-17-2015 08:57 AM
X2 Mill mod with High Speed Spindle Ethan D Machine Modifications 0 01-05-2015 11:32 AM
Mini Mill Spindle Lock Mod Ken I Machine Modifications 1 12-24-2014 03:29 PM
Help me buy a Mini Mill - Spindle Taper: MT #3 or R8? RMS General Engine Discussion 56 01-06-2011 08:17 PM
X2 mini-mill spindle thread Andrew_D General Engine Discussion 0 02-04-2010 03:38 PM



Newest Threads






- Top - Member List