Author Topic: chuck backplate  (Read 6043 times)

Offline John Rudd

  • Hero Member
  • *****
  • Posts: 2526
  • Country: gb
chuck backplate
« on: July 28, 2010, 07:53:08 AM »
Ok, calling on the collective knowledge of machinists...

I can obtain a blank backplate for a lathe chuck. It requires the centre drilling and tapping M40*4 for the lathe spindle and shoulder machining to take a chuck...

What is the correct procedure for drilling/tapping/machining?

Do I drill out the centre first, then machine the shoulder with the backplate attached to the spindle?

How is the backplate initially held when performing the operations required to make it fit?

How would you do it?

Your advice muchly appreciated
eccentric millionaire financed by 'er indoors
Location:  Backworth Newcastle

Skype: chippiejnr

Offline kwackers

  • Sr. Member
  • ****
  • Posts: 356
Re: chuck backplate
« Reply #1 on: July 28, 2010, 08:33:32 AM »
Set it up best I can in 4 jaw or faceplate.

Face, drill, tap to fit the lathe nose (without removing from chuck or faceplate).

Fit to lathe and machine to fit chuck.

Offline Davo J

  • Sr. Member
  • ****
  • Posts: 475
  • Country: au
Re: chuck backplate
« Reply #2 on: July 28, 2010, 12:12:26 PM »
If you are going to cut the tread on the lathe you can un screw the chuck holding the facplate turn the hole lot around to try it on the spindle without up setting the set up. Then if needed you can remount the chuck and take a bit more off.

Dave

Offline John Rudd

  • Hero Member
  • *****
  • Posts: 2526
  • Country: gb
Re: chuck backplate
« Reply #3 on: July 28, 2010, 02:03:33 PM »
Gents,

Thanks for the help so far....My first hurdle is to obtain some backplate blanks... :D

What should be used as a datum for centring the blank either on a f/plate or 4 jaw? Should I just go for a centre mark in the centre of the boss? I guess there isnt much else to clock from...
eccentric millionaire financed by 'er indoors
Location:  Backworth Newcastle

Skype: chippiejnr

Offline 75Plus

  • Hero Member
  • *****
  • Posts: 624
  • Country: us
Re: chuck backplate
« Reply #4 on: July 28, 2010, 04:46:53 PM »
John,

Not sure what size lathe the back plate is for but broken tread mills are a source for cast iron fly wheels. I bought a 2 hp tread mill motor and it came with a 7 kg flywheel made from fine grained CI. The center hole is a great starting point.

Joe

Offline Davo J

  • Sr. Member
  • ****
  • Posts: 475
  • Country: au
Re: chuck backplate
« Reply #5 on: July 29, 2010, 08:42:57 AM »
Weight lifting weights only have a 25mm hole in them. It is hit and miss weather you get a good one but there cheap at markets and yard sales to try on.

Dave

Offline Bernd

  • Madmodder Committee
  • Hero Member
  • *****
  • Posts: 3688
  • Country: us
  • 1915 C Cab
    • Kingstone Model Works
Re: chuck backplate
« Reply #6 on: July 29, 2010, 09:29:13 AM »
John,

Not sure what size lathe the back plate is for but broken tread mills are a source for cast iron fly wheels. I bought a 2 hp tread mill motor and it came with a 7 kg flywheel made from fine grained CI. The center hole is a great starting point.

Joe

Joe

Hey, never thought about that. Great idea. I'll have to try it.

Bernd
Route of the Black Diamonds