Unimat SL modification to improve control of milling depth

[Barkersoldbean]

Nice! Thanks for sharing.
So how much/ little travel per turn of the worm did you achieve?
Then just add a graduated scale to the worm and it'll be entirely repeatable!
Personally, I'm into this idea as a "poor man's dividing head" for the lathe's headstock for toolpost milling.

Thanks for the reply - I've checked the travel with a dial gauge (which is how i monitor travel across all axis rather than rely on the graduated scale).

Quite serendipitously - for each complete turn of the thumb wheel it moves the carriage by 1 mm - making operation using the thumb wheel (it's a unimat one with markings) without a dial gauge really simple.

The worm drive can be purchased via the following eBay link.

https://www.ebay.co.uk/itm/1-30-Redu.../362593141972?
ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

All you need is then a small block of aluminium that you mount everything into and a few bits of 3mm, 4mm and 10mm rod to make the various studs, bushes and axles.

The hardest bit was machining the aluminium block for the worm drive and the main drive gear - I took the easy route and used a pillar drill first to remove as much as I could before finishing it off via the milling head - even then it was very small cuts and a lot of shaking about!