Rotary Tool Support for Lathe

Sometimes one needs to do a bit of very small milling work and although I have a small, Chinese vertical mill as well as the Myford vertical slide which can be mounted on my little ML 10, neither of these tools will run at the high speeds necessary for very tiny milling cutters, drills or burrs.

To give myself yet another bit of flexibility in the shop I put together a little support unit that allows me to mount my Proxxon rotary tool onto the bed of the ML 10 metal lathe. With the vertical slide mounted on the back side of the carriage I now have a tiny milling setup that permits me to tackle some of the smaller tasks.

I’m certain that this idea isn’t at all new, but I’m posting these images in the hopes that they may prove inspirational for others.

The design of any such mount will have to be altered to suit whatever lathe and/or rotary tool you have at hand. The only construction details of note are relative to the way I constructed this support unit.

Having a TIG welder in the shop, I chose for a combination of mostly milling and welding, jumping from one discipline to the other as required.

You will note a little centering ‘mandrel’ that I turned out of aluminum rod held in my ER25 collet chuck which allowed me to center the Proxxon rotary tool clamp more-or-less on the centerline of the lathe. This tool clamp was TIG spot welded to the support in situ, the rest of the welding being finished away from the lathe. Whether the rotary tool really needed to be ‘on center’ is doubtful, but this arrangement did help assure that the rotary tool's shaft was in line with the bed of the lathe.

That's a useful idea. I think I will make one for my Dremel.

Rod

Add: I wonder if I could make a holder for the Dremel which I could hold in my fixed steady??

Rod

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That's an ingenious idea Rod ... I like it

MichaelG.

Neat!

A detail mod would have been to make a separate mounting block of appropriate height so you can put the Proxxon holder itself either on the bed as shown or on the saddle, the latter to allow you to use the drill rather like a Potts milling-spindle, for divided work.

A variant that fits on the saddle would allow you to use the drill for divided work such as pitch-circles of holes. In that case, centre-height accuracy and parallelism with the bed is important, but could be achieved by boring the clamp in-situ on the saddle, from the chuck - basically using the lathe as horizontal borer.

Nice work.

Steve.

A different take on a similar subject is to make an adaptor to mount the drill onto the quick change toolpost. More flexible in application, and more degrees of freedom to position the tool, or indeed to to get it misaligned!

Note the thread for the Dremel mount is 3/4 BSF, with a short counterbore for the shoulder section. The mounting hole centre is 12mm above the base of the adaptor bar to match my lathe tools, although the QCTP is of course fully adjustable for height.

The same holder can be used to mount the drill onto a rotary tool stand. The picture below is based closely on the design in http://mikesworkshop.weebly.com/rotary-tool-stand.html , so I claim no originality.

I have not tried it in anger yet - it has just been an interesting lockdown project!

Martin

The Proxon/ Dremel as Potts spindle is a good idea for drilling or milling work held in the lathe chuck or faceplate.

What struck me about Ignatz's setup is that it effectively creates a very high speed headstock spindle, admitedly at the "wrong" end of the lathe, which might have some special uses of its own, eg for turning small or very small work.

Rod

A suggestion: It would be helpful when cutting hard material or using bigger cutters, or saws, to add a support for the other end of the Proxxon as well. It could be a plate welded to the right end of the new attachment, perhaps.

Just a thought, might save some vibration or broken cutters.

Cheers, Tim

Add: Perhaps it would be possible to use the Ignatz setup, but turned end for end, and mounted on the lathe bed just in front of the lathe headstock. This would then be a high speed spindle for turning tiny work, and all the usual lathe movements are still useable, or one might mount a hand tool rest and use gravers. The Proxon/ Dremel would use up some of the length of the lathe bed but tiny work is likely to be short so this may not matter. cylindrical work could be held in the Proxon/ Dremel chuck or one might make tiny wax chucks for disc type work.

Any thoughts anyone?

Rod

Just to clarify: By reason of wear on the lathe bed of my old ML10, the carriage becomes uncomfortably 'tight' when cranked down towards the tailstock. For this reason it was the better choice for me to flip the position of the rotary tool support, working off of the back side of the cross slide so that most of the carriage movement is down closer to the headstock end. For those whose metal lathes are in better nick this wouldn't be an issue.

Like Martin (above) I also have a rotary tool support that fits into the quick change tool holder. This is extremely handy when using the rotary tool for cross milling, grinding or drilling of work held in the lathe spindle. However, when the rotary tool is held in the quick change tool post there is no way to use it in combination with the vertical slide.