Small spindle head

[bambuko]

Ah. so you dont need such tight tolerances at low rpm then?...

Didn't quite say this
It's a combination of target (comparatively low) rpm and light duty, that makes me think I can get away with a simplified design.

BTW, you have also asked:

...I'm interested to see what you are going to drive it with?...

Didn't give much thought yet. Definitely nothing fancy until I am convinced that I can make it work OK.
For the moment I have (don't laugh) sewing m/c motor and that will do for the testing.

[Ross77]

Sorry it was more of a question than a statement, Im still learning.

dont think I can laugh at the sewing machine motor, I'm one of those fools converting a pillar drill to a cnc mill :heehee:

[bambuko]

Before continuing with the spindle I needed to take care of my DTI.
Up until now it was all a bit Heath-Robinson and this was reflected in "variable" :heehee: results when it came to taper turning.
So first thing was to make a bracket for DTI, which would allow fixing of the clock directly to QCTP:



While at it, I have also checked my lathe (Prazimat from the old DDR)

My usual clock (with 0.01mm resolution) detected hardly any movement, so I used my new clock from Draper (0.001mm resolution):



Prazimat uses DIN55027 spindle head, size No3 and one can get chucks with this fitting on the back,
but they are rather expensive , so mine are all with usual backplate arrangement.

The reading on my Draper DTI was +/- 0.0015mm (total movement of 0.003mm) and just to check it I have tried my best DTI (with 0.0001" resolution):



The reading was below one division, roughly about +/- 0.00005" - 0.00008", with the total movement of about 0.00015

Now, the only thing I still need before setting the topslide with the DTI, is the straight probe for the front (instead of the usual ball-nose)
to overcome my usual difficulty of setting the clock exactly at the centre (usually ending with the taper not exactly replicating the original :naughty:)
Chris

[ptjw7uk]

Hi Bambuko
Thanks for your post it appears to anser one of my long running questions as to what type fixing my lathe has, it looks very similar to the one you have although my one is chinese as the Sieg C6.
I obtained a back plate for a C6 which fits but have had no luck in sourcing another.
I will check the measurements for the Din 55027 fitting now that I have them.
Peter