Tom, that's really interesting! That must mean that the drive is doubling the drive voltage at its output - I assume this is on a 230 V mains supply? I think if I could run at double speed it would meet most of my needs.

A friend has what is definitely a Taig / Peatol mill CNC converted in an enclosure labelled "Micromill" - did Denford make any MMs based on the Taig? I thought the machine was based on the Sherline.

A possible alternative approach, though it gives less benefit, is to use finger collets direct in the spindle. I bought a set of these from China, they effectively give an extra 50mm daylight.

OK, thanks for that information - sorry for my slow reply! As you say, a bit pricy! Maybe I'll just make something...

I think we all know that there isn't much room under the spindle, especially when you mount a typical BT30/ER16 collet chuck in it. I have been looking in vain for a short chuck - it is possible to get very low overhang BT40 chucks for ER25 and ER32 collets such as this: https://www.cutwel.co.uk/too...

Hmm... Well I was quite happily running a 1 mm endmill at 5000 rpm and taking 0.5mm cut in brass at a maximum feed rate of ~80 mm/min. I didn't break any cutters in 8 hours odd running. I needed to clear out 1.5 mm of material, and needed a 1mm cutter for the required detail. If I took 0.1mm cuts it...

I just wanted to resurrect this thread. I'm happily using my Novamill for 4 years odd now, but finding that the maximum spindle speed is a limitation. I'm usually cutting aluminium, sometimes brass, running the spindle flat out. I did a nameplate engraving job over Christmas using a 1mm cutter runni...

Is this still for sale please, and do you have a price in mind?

That's encouraging! I will check the thrust bearings and gibs.

Thanks, John.

Thanks, worth a try. But presumably the ballscrews aren't perfect anyway, do you know what the spec is for them, or what might be achievable on the Novamill please?

John.

Having had a couple of unexpected small tolerance issues, and being a newbie to CNC milling, I realised that backlash could be the problem. I measured the backlash at 0.03 mm on X and Y, and about 0.02 mm on Z. Are these of the order to be expected on the Novamill please? I have switched compensatio...

I recently did some engraving on my Novamill, which took a long time running the spindle at max revs. The headstock and the top of the column were pretty hot by the time I finished and it seems to me that the drive motor could do with some cooling as the column space has no venting to the outside. I...

OK, thanks for thinking about this...I'll watch out for it happening again.

John.

The other night I was in the process of referencing a piece of work using a wobbler, found that the collet chuck drawbar was only hand tight so applied a couple of wrenches to tighten it, then found that the spindle was seized solid! Groan, sigh, switched everything off (and yes, the spindle drive w...

Trouble with worm is how do you preload it to take out the backlash but with minimal friction? One route could be to use a recirculating ball arrangement like the old steering mechanisms - effectively a ball screw where the "nut" is replaced with a worm wheel. I'm not sure if these can be bought, lo...

That's a good idea.

Thanks Mike! I gether this supplier has resellers in France and Spain which I guess is why he is quoting euros. Food for though...when I built my drive box I included a 4th axis driver which is all ready to go but then started thinking about backlash etc so this might be a possibility.

John.

Mike, it's an interesting idea to make one using a harmonic drive. I've contacted the company but of course they ask which drive I would want! Did you specify a type number please? I wondered if there would be a few people interested in making one of these, to make it worthwhile buying a few drives ...

Thanks! I had a hunt but didn't find that one, wasn't using the right search terms.

John.

Mike, was that a 1-off from ebay or are they regularly available please?

John.