G. Thomas Versatile Dividing Head (Hemingway Kits)

[Bruno Mueller]

Don't worry, this will be a good and successful project.  You are on the right track.

[samc88]

Been demolishing my Dads kitchen lately so not had much shed time but found some time this morning to finish the bolts off

[Admiral_dk]

What can I say - I haven't been observant enough in your previous pictures of some of those Bolts 

But the latest ones brought the message home (the small pin that prevents them from turning) - so thank you for posting + they should do the job nicely for your build 

Per             

[samc88]

Thanks Per! Im happy with how they turned out and they fit nicely in the arm

Another part made tonight, the arm the plunger fits into for direct indexing with the holes in the gear. Bit more involved with it than I first thought as its actually tapered. I did this by lifting up one end with feeler gauges, I figured its more a visual thing so didnt feel the need to clock things in. The threaded hole is 1/2" x 32 rather than x 24tpi simply because I have a good tap and die set of this size. The bolt I made works nicely!

[samc88]

Finally some more progress tonight and Ive made up a satisfying little assembly in the plunger parts. Quite simple turning jobs but very satisfying to make, Ive assembled it temporarily to keep everything together and Im happy with the spring action of the plunger, all moves smoothly. Ill finish the end of the plunger once the gear is drilled so I can get a decent fit.

Ive changed the design slightly in that Ive not machined flats on the plunger sleeve and Ive not put a grub screw in the knob (ill use loctite instead) for no particular reason other than I think it looks better.

[samc88]

More progress at last, had loads on lately.

Made up the spindle nuts, was my first time internal screwcutting which was interesting, we shall see how succesful this was when I make the spindle!

Next up was finally setting up for boring the body of the dividing head on the mini lathe. I have a spare cross slide so decided to modify it to let me bolt the body to it with a couple of holes extra for clamps if needed. Using the boring head just because I have one rather than making up a boring bar. Boring head is a bit handier for letting me get in and measure the bore. Working really well so far, Ive just skimmed the bore to be round so far, I still need to clamp the brass spindle lock in place before opening it out too much

[springcrocus]

Coming along nicely. 

Regards, Steve

[Chipswitheverything]

I'd agree that the boring head does make taking measurements a lot simpler, but the head and bar does have a lot of overhang for a longish bore like this one.  If the two ends are measuring up consistently as the metal comes off, then that would be fine, but if the bore starts to show discrepancies, then it could be worth making up a simple , fairly large diameter boring bar for doing the final cuts. As the spindle is yet to be made, though the nuts are done now, you have a few thou of tolerance on the final bore size when making the last run through of the bar.  Dave

[samc88]

Thats kind of my plan, going to take the majority out with what I have and Ill make up a boring bar with the 1" material I bought which I will do during my break in work next week to get it to the final size. That was the other reason for using the boring head to start with, I havent got anything small enough thats the right length to go through the core hole. So far the bore is pretty consistent along its length which is surprisingly good

[Bruno Mueller]

For inspiration, perhaps a few pictures of my device. I have applied new paint.

[samc88]

Had a busy few weeks involving job interviews but i have made some progress! I did take the advice and made a boring bar which worked very well and got the main bore to 1 thou under the drawing dimension which I will take as a success!

Once that was done I moved the body to the right place for the tailstock bore using the Dial Indicator to clock the movement. I messed up a little as the book has you do the tailstock bore first and then the main bore so you can bore the tailstock itself at the right centre location. I think using the indicator to get the dimension needed and the DRO on the mill should fix that oversight though. Once I get this done Ill look at machining the outside to take the banjo arm. Im undecided on using the rotary table or taking it into work and making a mandrel to go on the larger lathe there

[samc88]

For inspiration, perhaps a few pictures of my device. I have applied new paint.

Thats a really nice looking tool, I hope mine comes out looking half as good as yours

[samc88]

Had great success finishing off the boring operations and the clamps work nicely on the 5/8" bar.

To do the tailstock I used my coax indicator to centre the body side to side and then a centre in the headstock to align the tailstock vertically. Happily it was bang on my original centre punch mark. This was then drilled and reamed to 1/2" for the half centre.

Next up is to do the turned boss at the end. I think Ill make a mandrel and do it on the lathe in work as I feel like Ill get a better fit and finish than on my rotary table. All in all Im quite happy with how this is turning out so far albeit a little slower than Id like

[samc88]

Fun with faceplates! To turn the end of the VDH body (after I discovered my lathe would swing it), I made a mandrel that was a tight fit in the bore which was then bolted up to the faceplate with some stud bar. Went for the faceplate as I could balance some of the weight out. Once the interrupted cut was over I did double check the mandrel with the indicator to be sure nothing had moved (it hadnt, the mandrel was very secure).

Very happy with how this turned out, got a very nice fit on the banjo arm (which still needs slitting for the clamp) and when I double checked with the tube micrometer the turned section was dead concentric with the bore. Other than a couple of cosmetic jobs Im happy to call this done and I can finally move on to getting other things machined

[Kim]

Very nicely done! 

Kim