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John Stevenson
11-29-2010, 06:59 PM
I wasn't sure whether to place this in the shop tools thread but it's not really a tool, in fact it was because I didn't want another tool I came up with this.

Problem:-
Big stack of Oilite bushes that require turning down on the OD to a special size.
Bore is a standard 20mm, tad over 3/4"
These need to be held on the bore and turned on the OD, many ways to do this, expanding 5C arbor, specialised arbor with retaining nut and washer etc. Problem with this method is you can only do one at once unless you make a long arbor up which is what I didn't want to do because it's probably a one off job and even if it comes up again I would have lost or forgotten about it, so try to do multiples without the hassle of specials.

Sooooooooo

Take a piece of off the shelf 20mm diameter scrapbinium [TM] face the end and centre drill it.
Fit to chuck with washer on next to jaws to protect them and slide bushes in, in this case doing 4 at a time.

http://www.stevenson-engineers.co.uk/files/arbor1.jpg

Now slightly loosen off chuck jaws, bring tailstock up with revolting centre and force the shaft back thru the jaws until everything is solid, then tighten jaws.

http://www.stevenson-engineers.co.uk/files/arbor2.jpg


That's it job done, the centre will drive the bushes and the tip of the centre is hard on in the shaft so everything is fully supported and running true.

http://www.stevenson-engineers.co.uk/files/arbor3.jpg

Shot with centre retracted to show how it sits. Now you can skim the 4 bushes and then do the next lot. If the lengths are accurate then you don't need to keep resetting but if not just push the bar back thru the jaws and nip up.

When you are done the length of shaft can go back in the bit box until it's needed for another job, nothing wasted and plenty of time saved.

.

mike os
11-29-2010, 07:02 PM
so, where can I get this scrapbinium (TM) you are on about?:rolleyes:

Toolguy
11-29-2010, 07:15 PM
Looks like a great idea! I will have to try to round up some scrapbinium [TM] and a revolting center.:p

recoilless
11-29-2010, 08:01 PM
Now slightly loosen off chuck jaws, bring tailstock up with revolting centre and force the shaft back thru the jaws until everything is solid, then tighten jaws

Yes, please tell us more on this peice of kit. It must have been made in Barcelona??

John, is there anything you suck at? You strike me as a sickeningly logical person.;) Perhaps you are a horrible cook, or you spill a lot of drinks.:rolleyes:

Cheers.

motorworks
11-29-2010, 08:11 PM
John
Nice...a keeper...love the fact that your lathe has as many coloured chips on it as mine...and that fish tin...priceless :)
eddie

Arcane
11-29-2010, 08:52 PM
Perhaps you are a horrible cook, or you spill a lot of drinks.:rolleyes:

Cheers.


Sir John spill a drink?? Not bloody likely! :D

John Stevenson
11-29-2010, 08:58 PM
Must admit I did spill one once, round about '62 or '63. Since then with the terrible incidence being on my mind I always buy two pints when I go to the bar...........

Dan Dubeau
11-29-2010, 09:27 PM
Must admit I did spill one once, round about '62 or '63. Since then with the terrible incidence being on my mind I always buy two pints when I go to the bar...........

One in each hand is the perfect balance. Nice arbor John, quick and dirty solution to a quick and dirty problem.

Don Young
11-29-2010, 09:39 PM
A really simple but elegant solution to a basic problem. I like it.

Mark McGrath
11-30-2010, 01:48 AM
Must admit I did spill one once, round about '62 or '63. Since then with the terrible incidence being on my mind I always buy two pints when I go to the bar...........

I think the word to pay attention to here is "when",as in when I go to the bar.

doctor demo
11-30-2010, 03:30 AM
A really simple but elegant solution to a basic problem. I like it.
I have to hand it to You John, that is a good quick trick.

Steve

winchman
11-30-2010, 04:21 AM
Two minor observations on your clever solution:

You really didn't need to face and center-drill the rod. The ID of the end bushing is positioning that end of the stack.

How much error does your 3-jaw chuck have? Whatever it is shows up in the concentricity of the ID/OD of the first bushing, and to a lesser extent on the other three. Probably not enough to matter, but could be a factor for anything requiring great precision.

What are the bushings used in?

John Stevenson
11-30-2010, 05:06 AM
Two minor observations on your clever solution:

You really didn't need to face and center-drill the rod. The ID of the end bushing is positioning that end of the stack.

How much error does your 3-jaw chuck have? Whatever it is shows up in the concentricity of the ID/OD of the first bushing, and to a lesser extent on the other three. Probably not enough to matter, but could be a factor for anything requiring great precision.

What are the bushings used in?

You know I think you are right about the centre drill, bushes are still here hopefully being collected today, I'll setup again with the bar reversed to the sawn end and run it again. Thanks, another 15 seconds saved.

3 Jaw is very good, it's an off the shelf TOS as fitted to all my machines. Runout is around a thou, if I mark the work with a felt tip to the no1 jaw I can remove it and refit it. This is my most used lathe and I buy a new chuck every 3 or so years and hand the old one down. 3 years to me is probably a lifetime to the HSM guy.

No idea what the bushings are for, the job is for the local bearing supply house.

Circlip
11-30-2010, 10:08 AM
No idea what the bushings are for, the job is for the local bearing supply house


OH NOOOOOOOOOOO, I told them they needed to be within 3 microns of a Gnats c**k hair for concentricity.

Just can't get the skill nowadays, well, not if you want to pay less than H/F, Grizzly or Nco prices.

:D