Author Topic: Another doodad for my lathe...  (Read 8487 times)

Offline arnoldb

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Another doodad for my lathe...
« on: September 03, 2009, 05:16:03 PM »
As one of the "parts" I needed to make for my ER collet chuck is a spindle nose replica for my ML7, I thought about putting it to good use.

Not having a milling machine  :( (Yet!) and always having to set up and align the vertical slide and my prized original Myford dividing head to do "menial" jobs, while sacrificing rigidity, I have been toying with a "quick-index" I can mount on the cross-slide to do these jobs.  The dividing head can also be VERY awkward to set up for some jobs; there sometimes just is not enough travel available to use it!!!

So this thread is about "turning" (pun intended  ::) ) a part needed for one project into a useful bit for another.

I started with this:


While the collet-chuck-in-making was still in the lathe, I screwed the nose replica into it, and turned down the unfinished end to 30mm:


Some drilling followed and then tapping M10 from the tailstock:


As the collet chuck-in-making was still mounted in my 4-jaw chuck, I used the 3-jaw to turn a base plate - the deepish dimple  in the center is just to make sure that the plate will lie truly flat on the cross-slide:


After scratching around my available material, I found some HRS bar stock that should work for the column, but it was slightly too narrow, so I turned the spindle shaft down further to 22mm; Not having removed the collet chuck body from the 4-jaw, I just screwed the new spindle into it,and the whole lot back on the lathe and turned down - no run-out  :headbang: - VERY nice!
I also used a piece of 10mm square bar stock to make a mounting guide with a 5mm hole at the half-way mark and equivalent 5 mm threaded hole in the base.  The guide and base were screwed together, and set square, and then I drilled and reamed 6 mm holes through both guide and base at the ends of the bar. 2 short pieces of 6mm silver steel loctited into the guide ends , and it can be removed if needed, and placed back accurately.
Here is collection of spares so far:


With some welding, boring, slitting et al, the lot will go together sort of like this:


There's still a lot to be done: a quick-index 24 hole plate, and a worm and gear drive to be used for milling curves.  I will also add additional bracing to make it more rigid. Another "simple" job turned into  :proj:  :doh:

 :beer: Arnold

Offline sbwhart

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Re: Another doodad for my lathe...
« Reply #1 on: September 04, 2009, 07:35:36 AM »
Nice Idea Arnold  :thumbup:

I may have use for this one with a little project I've got in mind.

Thanks

Stew
A little bit of clearance never got in the road
 :wave:

Location:- Crewe Cheshire

Offline CrewCab

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Re: Another doodad for my lathe...
« Reply #2 on: September 04, 2009, 04:01:53 PM »
Nice work Arnold, and ............. I suspect your having fun  :thumbup:  ........... Good man  :beer:

CC

Offline arnoldb

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Re: Another doodad for my lathe...
« Reply #3 on: September 05, 2009, 04:24:08 AM »
Thanks guys  :beer:
Stew, you're welcome; I'm building this off the top of my head with any available material, so I don't have a drawing or exact dimensions.  If you'd like, I could make one for you once done.
CC - your suspicions is spot-on  :) :)

Cheers, Arnold

Offline sbwhart

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Re: Another doodad for my lathe...
« Reply #4 on: September 05, 2009, 08:36:37 AM »
Hi Arnold

Just watching your build will do the trick, I'll probably use different material than you depending what I've got in my stash, as long as I get the idea  :scratch:.

Thanks for the offer

Have fun

Stew
A little bit of clearance never got in the road
 :wave:

Location:- Crewe Cheshire

Offline arnoldb

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Re: Another doodad for my lathe...
« Reply #5 on: September 05, 2009, 03:48:33 PM »
That's fine Stew - I hope there's something in this thread that will help.

Some more progress today ( :offtopic: After a run-around in town and to my office to collect a car full of written off printers and flat screens; might be able to use those  :lol:)

The 2 blocks of metal that will make up the column was given a dress-down on the bench grinder to make some nice fillets to weld in.  These welds must go to just below the center line of the column; I want to keep the tops split, as one top part will become the main bearing with a screw for adjustment, while the other will get a screw with handle for doing locking.  First photo shows the two column halves clamped together in the big vice prior to welding with a nice V-Groove to do the weld in:


I could have gone the route of bolting everything together, but I feel I'll get more rigidity with the welds. (Also, I'm lazy, so I'll skip trying to find bolts and drilling and tapping holes  :lol:)

Next up, I had to clean off excess from the welds - just chucked the lot in the 4-jaw and had at it.  The first side was more difficult than the second, as there was a raised weld against the chuck body that had to be compensated for... :


Next up, another piece of HRS flat bar was relieved of it's outer layer - this will make a back-column, on which to mount the quick-index pin, and the worm drive screw.  Here a pretty major flaw becomes apparent in my design so far... If you make a similar device, make the spindle long enough.  I'm going to have a right bugger of a time adding an extension piece to my spindle that is 100 % concentric through the back column.  It can (and will) be done, but it's going to take a good amount of effort to set up accurately...  Only reason my spindle is too short, is because I'm re-using things from the other project - when it didn't matter.

Here's where I stopped today; the old brass electrical fitting will become the front thrust washer, and I'm considering using a slice of the cast iron as an index plate/worm wheel combination.  Ignore the bolt; that will be replaced by a turned steel shaft (from an old dot matrix printer <grin>).


The base has already been drilled for taking the bolts for T-nuts to clamp to the cross-slide.  Those are the ones between the 2 columns - spaced for the Myford cross-slide.  I also drilled additional holes at the nose side - those are spaced at Myford spacing from the main bolt holes; If I remove the "square-ing" bar, the whole lot can then be clamped at 90 degrees on the cross-slide or vertical slide.  Not really needed for now, but easier to do now rather than later if it may be needed.

Once the columns are welded into place, I'll have to make a boring bar to bore the spindle holes to size... Make a tool to Make a tool to Make a tool to Make a tool to....

Cheers, Arnold