First question on new toys, dividing head and rotary table.

[John Hill]

OK, I got these new toys and they look very nice on the bench,  rotary table, dividing head and three jaw chuck.

I assume I should arrange for mounting the chuck on either device?

The rotary table has a MT2 centre taper and the dividing head has a B&S taper plus a threaded spigot.  BTW my lathe has MT5 spindle and a camlock D1-4.  Hmmmmmm.......  I recall Bogs going to some effort to be able to move his chuck from one machine to the other without disturbing his workpiece....

The new chuck has no backing plate, just the turned recess and three screw holes.

For the rotary table, I could make a backing plate for the chuck with a MT2 taper plus lugs around the edge to give something to clamp with.  If I drill that for a drawbar I could use the same plate in the lathe if I turned a MT5 on the back of the back plate (I would not be able to put work through the chuck in that case but I dont think I would be doing that if it was going on the rotary table anyway).  I could avoid the need to clamp if I make a drawbar for the rotary table but I would have to dismount the rotary table to fit the chuck.

There is a threaded plain face plate with the dividing head and if I had a way of mounting that on my lathe I could turn a, shallow, MT5 taper in the centre of that and make a short drawbar to hold the chuck on.

Hmmmmmm.......  It might be possible to make a single ungummins for the chuck that would fit all devices.

[Artie]

Hi John, coffee, a browse through old posts and inspiration will strike.

I bolted mine together but I used an independant 4 jaw which doesnt have the scrolls that you have so I could easily bolt through as per the pic below. Not an option for you mate.

Chuck did a really simple home made rotary table for simple rounding off etc and Im considering making one and mounting another chuck in that, possibly a 3 jaw scroll. We'll see, Ill pop in his youtube link... simple and effective, for a lot of your rotary milling, indexation and geared drive is not necessary (roundng off etc).

Good luck mate....

[DeereGuy]

John,
Here is a link to what I am selling to just what you are talking about.  This link will let you see what they are.  Send me off and email if you are interested.  

I have two d1-3 adapters to make before I can get to another D1-4

These take up 1.4" of z index.

http://madmodder.net/index.php?topic=4316.0

And BTW..congrats on the new tools.)

Also I shipped one to New Zealand two weeks ago via USPS.  The shipping was around $45 US dollars and took 6 days.

[John Hill]

Thanks Bob, that is very nice work!  Good luck with this project!

I am however going to try the approach of using a taper for centering and either draw bar of peripheral clamps for fixing. 

John

[lordedmond]

I did the same thing by buying a small three jaw bolt though chuck  and use that as a dedicated RT chuck as the small chuck have three holes and the RT has three slots its a no brainer.


To centre the RT I start without the chuck ( unless I know the chuck is centred ) I have a sx3 which is smaller than yours .I have a stub mandrel that fits the mill and is turned down to just enter the RT bore , leave the RT lose and lower the stub int the RT tighten up the RT and zero the scales . fit the chuck  loosely lower the stub into the three jaw tighten up the chuck and then bolt down . If I know the chuck is centred then I skip the first step .

It may not be perfect but works for me



Stuart

[Bogstandard]

John,

Your dividing head should have a Myford nose screw on it 1 1/8" X 12TPI, so maybe that should become your standard, which is the way I went.

This is the start of it all, and they can be bought from both RDG and Chronos for very little money.

http://madmodder.net/index.php?topic=422.0

http://www.chronos.ltd.uk/acatalog/Morse-Taper-Chuck-Adaptors-for--Rotary-Tables-2MT-Myford-Thread.html

Then I could  turn backplates etc to fit a whole range of fittings, knowing full well that I can easily screw them onto my RT, dividing head and lathe. Allowing me to turn a part on the lathe and transfer it onto the mill without having to disturb the part in the chuck.

Ready threaded backplates can be had very reasonably from almost any of the UK suppliers and save all the trouble of making them yourself.

http://www.chronos.ltd.uk/acatalog/5---Backplate-Threaded-to-Suit-Myford.html

Later, I made a dedicated adapter that fitted into the spindle of the lathe, 5MT to Myford nose.

http://madmodder.net/index.php?topic=1993.0

You can easily make a fitting to go onto the RT to take the Myford backplate, but Chronos do a very nice cheap one, that I have just changed my home made one to as it spreads it over a larger area. But it only fits the four slot RT, even though made for 3" and 4" tables, it fits mine perfectly.

http://madmodder.net/index.php?topic=2002.0

http://www.chronos.ltd.uk/acatalog/3_Rotary_Table_Adaptor_with_Myford_Thread.html

Something for you to think about.


John

[jiihoo]

(While I was typing the other John wrote the "correct" way to do it. I will still post this as this way does not require any extra accessories, just a piece of aluminum plate.)

In case the chuck is smaller than the rotary table: How about making a backing plate the same size as the rotary's table. Fix the chuck to the backing plate with countersink screws from below. Then drill holes on the part of the backing plate outside the chuck and use these holes to fix it to the rotary's T-slots with T-nuts and bolts.

Phase 1 done and you can start using it. (requires centering the chuck on the rotary once as there is nothing to guide it.)

Phase 2: make a hole in the center of the backing plate. Put a blank arbor on the rotary. The hole in the center of the backing plate slips on the end of the blank arbor. Now you have your "guide pin".

I suppose the above won't give you the ultimate accuracy and might not be the best way if you need to transfer the chuck between lathe and rotary. But it might be the fastest way to get the chuck on the rotary and get it in use.

Cheers,


Jari

[kvom]

I got a separate cheap Chinese flat back 3-jaw chuck with 2-piece jaws for my rotab, esp. as my lathe is a D1-3 spindle.  I made a backing plate for attaching to the rotab, and aluminum top jaws.  Since I mill the jaws using the rotab, they are precisely centered when holding round work.

[John Hill]

Thanks for that information John, I remembered that topic of yours but then I forgot to go and find it!


Is there ever an issue with the Myford thread moving and spoiling the work?

[Bogstandard]

John,

I have done some fairly rough stuff with it and still nothing has moved. All I do is tighten up the RT locks to prevent damage to the worm, put a bar across the jaws and give it a good tweek. I undo the same way.


John