Another way to cut a face groove

A few days ago I posted a question about how to cut the face groove on this part of the Quorn Mk3 I'm building

There were plenty of suggestions including making a trepanning tool, purchasing a face grooving tool or making a multi-tooth cutter like a hole cutter.

I tried making a trepanning tool but by the time I had ground the necessary relief on the 1.6mm wide, 4.9mm deep tool, there was almost nothing left and it snapped immediately. I do not have the necessary grinder to make a curved trepanning tool. Commercial tools are available but £100 to cut a few grooves was not justifiable. I also did not have a piece of silver steel of the right size to hand to make the 'hole saw' type tool. I therefore arrived at another solution.

I've got a 'Quick Step' toolpost mounted milling attachemnt and set this up in the lathe as so..

The chuck was set rotating at 20rpm and the 1.6mm slot drill was running at 4000rpm. The carriage feed was set to 0.04mm/lathe revolution.

Worked rather well. The 4.9mm depth was reached without misshap on both parts.

Resulting slot was almost exactly to the specified 20.6mm i.d.

This is the first tme I have used the Quick Step in this way with the workpiece rotating but seemed to work. Result !

Well yes ... if you are fortunate enough to have the right tool available, it would be a shame not to use it.

MichaelG.

I'd have used my milling machine and rotary table, but only because I don't have a Quick Step attachment for my lathe.

Martin.

Edited By blowlamp on 06/06/2020 12:20:57

Yes, that was 'plan B' and would have worked fine as well.

Ifoggy:

Was that impressive toolpost base in your photo not written up somewhere?

I don't recall you mentioning having that milling attachment in your original thread.

Loosely based on something I saw on YouTube. Its just a block of cast iron machined to fit the cross slide, nothing special. Has really improved the rigidity of the toolpost though. Because of its size the whole cross slide is stiffened as well.

Ifoggy:

Thanks. The base I was reminded of made a feature of chip-shedding planes - stealth technology for lathes!