MadModder

The Shop => Tools => Topic started by: DICKEYBIRD on November 08, 2009, 09:35:45 AM

Title: Cheap tailstock DRO
Post by: DICKEYBIRD on November 08, 2009, 09:35:45 AM
There's been quite a few similar mods posted here & there so yesterday I jumped on the bandwagon and converted my tailstock to digital depth display.

I picked up a 4" Chinese caliper on sale at HF and proceeded to hack it to bits with a dremel cutoff  wheel and drilled some mount holes.  I dreaded the drilling because of the hard stainless steel but carbide circuit board drills whizzed through it like butter!

My tailstock quill rotates a bit so I made the slide to quill connection with a shortened pair of r/c helicopter ball links screwed together with a bit of 2-56 threaded rod.  It's a slack-free connection and assures no-bind operation.  It works so well I wish I'd done it much sooner!

Here's a few pics:
Title: Re: Cheap tailstock DRO
Post by: bogstandard on November 08, 2009, 10:12:11 AM
Very nice indeed.

Isn't it nice to be able to drill accurate depth holes?


Bogs
Title: Re: Cheap tailstock DRO
Post by: DICKEYBIRD on November 08, 2009, 10:30:15 AM
Yup, I'm not sure I'm ready to deal with knowing EXACTLY how deep a hole is instead of peering at a dark, unknown thing that "looks about right."
Title: Re: Cheap tailstock DRO
Post by: jim on November 08, 2009, 11:14:43 AM
excellent! :clap:
Title: Re: Cheap tailstock DRO
Post by: Stilldrillin on November 08, 2009, 12:56:32 PM
That`s nicely done!  :thumbup:

David D
Title: Re: Cheap tailstock DRO
Post by: Yorkshireman on November 08, 2009, 01:31:26 PM
The metal of the Caliper is a bitch to drill (opps, language!).
how was is done here?
Johannes
Title: Re: Cheap tailstock DRO
Post by: DICKEYBIRD on November 08, 2009, 03:09:02 PM
I used a couple of drills from this set I bought a long time ago.  I think they're surplus carbide (overstock) GF circuit board drills.  They were unbelievably cheep.

I cranked up the mill to its highest speed, (2000 rpm) put a drop of cutting oil on and peck-drilled straight through, easy-peasy.

(http://i57.photobucket.com/albums/g227/DBAviation/Gloat10-082.jpg)
Title: Re: Cheap tailstock DRO
Post by: Jonny on November 08, 2009, 03:26:40 PM
Had to butcher scales on smaller mill 9 years ago, quite easy decent drills and get a feel for it cutting. No good forcing if its not cutting, it only generates heat.

Bought a load of boxed calipers some years back £1.50 each, sold em all.

Keep all liquids off ive knackered a good many inc two Mitutoyos.

That scale would be in the way for much of what i have to do, though good work have to query why the ball links.
Title: Re: Cheap tailstock DRO
Post by: DICKEYBIRD on November 08, 2009, 04:38:03 PM
...have to query why the ball links.
Because the caliper is rigidly mounted and the T/S quill rotates a bit due to wear in the indexing pin.  If I rigidly mounted the slide to the quill, there would be unwanted binding and wear in the caliper.  The double ball links eliminate the problem without adding any slop to the connection.

It'd work without them but I don't like to build-in a known fault.  Make sense?
Title: Re: Cheap tailstock DRO
Post by: ariz on November 09, 2009, 05:28:09 AM
to me it appears a very well done mods  :clap:

Title: Re: Cheap tailstock DRO
Post by: bogstandard on November 09, 2009, 07:29:47 AM
DICKEYBIRD,

The way you have done it with the moveable joint is the correct way to go about it.

99% of lathes have some, even though it might be very small, rotary movement. That joint is the only thing protecting the rigidly mounted unit. I had to do the same thing when I mounted my DRO read head on the tailstock.


Bogs
Title: Re: Cheap tailstock DRO
Post by: NickG on November 09, 2009, 10:49:47 AM
Well done Dickeybird.  :thumbup:

Was having a look at mine the other day and it'd definitely need a moveable joint, it does rotate a bit. Really want to do it but there isn't a straight edge anywhere on my tail stock! I suppose you could say that's just an excuse as I should be able to drill and tap it and make some sort of bracket then measure from that. Or some how clamp it on the milling machine and spot face a bit? Any ideas chaps?

Nick
Title: Re: Cheap tailstock DRO
Post by: DICKEYBIRD on November 09, 2009, 11:49:23 AM
If the T/S quill is a size that fits a 5C collet, run it out a bit, lock it down, clamp it in a collet block or spindex, add a few clamps and jacks to secure it to the table and then mill a flat or 2.