Gallery, Projects and General > The Design Shop

Tailstock rack handle position?

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Fergus OMore:
Hi Peter,
             I suspect that I still have all the Cleeve article as a photocopy.
It is tucked in behind Chaddock's original Quorn articles. What seems important is that Cleeve's stuff was extremely simple and cutting the rack on his lathe was fully explained.
I'm still not very well after a month of pneumonia but could try to copy the copies which were somewhat ancient and prior decent home photocopying.

Perhaps a PM with a proper e-mail add will get you  the information

PeterE:
After some e-mail conversation I have got some new info to add to my thinking, will be back when done.

Another question on the fly; In most cases the rams are made from  ordinary bar stock of suitable diameter, but would it work equally well with a threaded rod? I am thinking of a stainless threaded rodding which I think keeps to sizes better than ordinary galvanized ones, and the A2 quality should still be OK to machine.

Using a threaded rod of 20 mm dia x2.5 mm pitch would make for quite a rack, and to make a "nut" to drive it should be possible using a tap of the same size.

Just an idea to easily find material...

BR

/Peter

andyf:
Getting back to the ergonomics, Peter, I think that the three diagrams you showed point the way. Taking drilling a hole as an example, in A it would be natural to grasp the handle which is nearest to you and move it CW it towards the headstock to apply pressure on the drill bit.

In C, it would be equally natural to grab the topmost handle and move it CCW.

B is the problem situation, where you might need to think things out.

Personally, I would go for A, because there is very little chance of the arms fouling anything as you turn them. Even better would be half-way between A and B, so that the arm nearest to you was more or less horizontal.

Andy

PeterE:
Hi Andy,,

I can only agree with you here. I have come to the same conclusion myself, and I think I want to make a mock-up out of odds and ends just to find the right angle och the gear housing and the angle on the star wheel arms vs the gear housing.

As you say the housing should probably be nearer the A position than half way between A and C, but how much will be decided by the angle of the arms, and with the right combination the star wheel will not foul any other handle either.

I did get some more info = the old Martin Cleeve descriptions and found some useful info there as well. He had decided to skew the star wheel axle to be in a horizontal position but turned about 20 degrees outwards to the right thus turning it away from the bed handle and such.

Still working out the boundaries and types of items, and then I willb e back with more.

Thanks for comments they really help much in differnt ways.

BR

/Peter

PekkaNF:
How is this  :proj: coming up together?

Saw this;
http://www.lathes.co.uk/elffers/img16.jpg

And remembered this thread,
Pekka

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