I have a Hercus 9, a Hafco AL336, and two compatible QCTPs;
so I can use the same holders, and mostly 16mm tools, in each.

Now, the lathes' centre heights are close, but not exact.
(My measurements say Hercus 26.2mm, Hafco 31.5mm, above the compound slide)

For a while I used a big washer on the Hafco, about 4.5mm thick,
to lift the QCTP above the Hafco's compound slide.
It made the tools nearly useable without adjustment, but not quite.
(I am too lazy to keep adjusting the centre height)


Last week, I found a little bit of odd scrap, about 6mm thick, and did some machining.
But not the obvious washer shape!

Mount the scrap on a mill,

find a not totally blunt 12mm end mill:		 IMG_1438.jpg and start to mill a T slot nut profile.
Relocate the clamps: IMG_1441.jpg and mill the back step.
Locate the washer somewhere safe to drill: IMG_1444.jpg and centre the cutter in my badly machined step.
Plunge: IMG_1445.jpg which, due to my badly milled steps,
was not in the centre of the washer
Found an 18mm drill, enlarged hole. no pic Tested in top of compound slide.
Hole not centred perfectly -
had to file one side a little.
Time to try something new -

surface grinding!		 no pic Spent at least an hour practicing,
on the old 4.5mm thick washer.
Wheel survived a few too wide,
and too deep, grinds.
Align step with a D.I.: IMG_1446.jpg so I can grind into the corners.
A lick across the front,

then the back,

then the		 IMG_1447.jpg and 2 hours later I have some mirrors!
Also did the tricky/dangerous part...

grinding the flat		 no pic but I didn't use transfer blocks.

I just magnetised the middle step,
and did VERY shallow cuts.
Test fit on the compound: IMG_1448.jpg
and, IT FITS!!!! IMG_1449.jpg A satisfying tight fit -

good end to the day.

Time to go home.
Day 2, align the QCTP: IMG_1454.jpg with the compound at an angle

(here, 30° clockwise)
and mark a centre: IMG_1459.jpg with a transfer punch
in the QCTP location hole.
Repeat at a few other angles: IMG_1461.jpg for some other common angles.
Do some drilling and try to de-burr and have to use a file instead
and voila: IMG_1463.jpg one scratched,

but useable,

QCTP location plate!





So, some discussion is in order.


Even though I have never used one, I like the idea of 4 way toolposts, that they have a detent* to align them (mainly for parting off). However, I think it is silly that they only align with the compound at 0/90/180°?

I thought about mounting a 4way as a rear toolpost, but most lathes can't move the cross slide close enough to the operator for this to be useful?

So, I frankensteined this solution. Which is just a prototype really, but I'll see how much time it saves me.





(*) Speaking of detents, wouldn't it be nice if the compound had a detent or two to align at useful angles?
Like a mitre saw?

I set at 30° a lot - mainly so the compound clears the tailstock, but 0/45/90/135 and 60 would also be useful.
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