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chambezio
6th April 2009, 01:44 AM
Does anyone have a drawing or can point me in the general direction of a drawing/design of a tool rest that can be moved and adjusted by one lever that actually works on the tool rest bracket and the toolrest itself with one action only.
I am pretty sure I have seen them on some production lathes but my mind can't figure out how to do it.
(Or am I imagining that I have seen them):?
Regards Rod

arose62
6th April 2009, 01:37 PM
Are you saying that you want a single lever to:

a) lock the toolrest banjo down to the lathe ways

AND

b) lock the toolrest post height and rotation ??

I can imagine that two cams on the one shaft could do it, but it would mean that when you release the lever to move the toolrest along the lathe, the toolrest would also drop down to its lowest point.

bobsreturn2003
6th April 2009, 01:50 PM
most lathes have this .woodfast vicmarc etc , once you see how its done , its quite simple . metalwork wise you need a lathe& welder etc to make one . cheers bob.

RETIRED
6th April 2009, 05:31 PM
I've never seen one but then I haven't seen everything yet.:D

new_guy90
6th April 2009, 06:12 PM
it doesn't sound that hard to do i mean if you have access to a metal lathe, independent 4 jaw chuck, miller and spare time to kill then yeah it shouldn't be to hard but for the life of me i don't see the point :? it think you would need to really think about what your doing to move it and wouldn't save much time :(( but its a good idea show us a pic if you make it

Patrick

chambezio
6th April 2009, 11:57 PM
Are you saying that you want a single lever to:

a) lock the toolrest banjo down to the lathe ways

AND

b) lock the toolrest post height and rotation ??

I can imagine that two cams on the one shaft could do it, but it would mean that when you release the lever to move the toolrest along the lathe, the toolrest would also drop down to its lowest point.

Yes I think I want to lock down to the lathe ways.That bit is quite simple(in my minds eye)
It would be quite another engineering puzzle to use the same lever to lock the tool rest itself (in my minds eye)
When I wrote this thread last night it was quite late and may be my mind was thinking about bed. But you are dead right about the rest dropping down when the lever releases it. May be I should just work on the cam to
operate on the tool rest bracket and adjust the rest with a threaded lever
Thanks for your reply
Regards Rod

RETIRED
7th April 2009, 12:02 AM
Yes I think I want to lock down to the lathe ways.That bit is quite simple(in my minds eye)
It would be quite another engineering puzzle to use the same lever to lock the tool rest itself (in my minds eye)
When I wrote this thread last night it was quite late and may be my mind was thinking about bed. But you are dead right about the rest dropping down when the lever releases it. May be I should just work on the cam to
operate on the tool rest bracket and adjust the rest with a threaded lever
Thanks for your reply
Regards RodThat's the norm.

chambezio
7th April 2009, 12:08 AM
it doesn't sound that hard to do i mean if you have access to a metal lathe, independent 4 jaw chuck, miller and spare time to kill then yeah it shouldn't be to hard but for the life of me i don't see the point :? it think you would need to really think about what your doing to move it and wouldn't save much time :(( but its a good idea show us a pic if you make it

Patrick

The metal work side of things isn't a problem, as I have a metal lathe, welder, time and access to a capable bloke with a mill.
You are right to wonder why I would want to use the one lever to do the 2 operations. I should be content using the cam lever to release the bracket only, and use a separate lever to adjust the tool rest itself.
If you check the previous reply my pathetic excuse was that it was late when I wrote the thread and I probably should have been in bed:doh:
Kind reards Rod

Skew ChiDAMN!!
7th April 2009, 12:28 AM
You can always make a bush to slip over the tool-rest post, locked in position with a simple grub-screw or lever or whatever to hold it at a preset height.

This'd prevent it dropping with the system you suggest.

Personally, I don't like the idea. As I usually have the rest very, very close to the work, I like to swing the rest away from the piece before releasing/moving the banjo to reduce the risk of the rest clipping the wood.

Once or twice I've failed to relock the tool-rest after swinging it out of the way and, while moving the banjo, it has freely swung back and done the damage I was trying to avoid. :B

Operator error, admittedly, but your method would make it far more likely.

chambezio
7th April 2009, 01:00 AM
The more I read your replies the more I think I will only put the cam on the bracket. I think it will be a better propsition in the long run
Thanks for your thoughts. A lot easier to build up things change them and knock them down here in front of the computer that out in the shed chewing up electricity and material let along pulling out hand fulls of hair!!!

Kind regards Rod

new_guy90
7th April 2009, 06:34 PM
making a cam is very easy im sure you know that and its a fairly simple milling and boring job i think you could just weld up a new banjo and mill it up in an arvo and the cam would be a good evening after work but yeah i know what you mean i have 3 bolts to move my banjo and tool rest but i cant get out of it as my lathe is a bar bed one so it really sucks ......also you can just make a box that goes over the old banjo to work as your cam but its very weird and you have less swing

its not hard so why not give it a try oh and while your at it take some WIP pic's :D

patrick

joe greiner
7th April 2009, 11:53 PM
I thought I replied to this yesterday, but I guess I didn't. The whole idea seems like a solution in search of a problem. I usually want to adjust one of them, without changing the other. Combining two independent output results with a single input destroys their independence.

Do you work for the Government?:D

Cheers,
Joe