Sorby large bowl turning

[Popkorn]

Hi, I am on a mission to find a Sorby large bowl turning extension arm. Sadly these items are now no longer made and I missed the chance to buy one when I first bought my lathe (many years ago now).
If anyone knows where one can be found, or if anyone has one and can provide size specs to enable me to make one I would appreciate it.
Look forward to a reply in hope, but not expectation.
John

 

[CHJ]

Based on an assessment of that design I would be say it may not be all that rigid and stable.

I think you would be better off making a floor standing tool rest support, the tool loads will then be transmitted down into a solid support rather than trying to twist that cantilevered construct.

 

[Popkorn]

It was very rigid and surprisingly stable, cast iron and quite heavy, as was the price which at time was beyond me.

 

[Dalboy]

The other option which may be a thought but I am not sure if it would work ither that the idea Chas made of a floor standing rest is would a record power one be adapted to fit as theirs is also for twin bar system. The main thing with record power is it is designed to also be a foot and support for the lathe.

 

[nev]

As above, could an RP one be adapted or added?

Just had a quick measure, the RP(CL2 - but I believe its the same as the CL3) has 37mm bars, approx 100mm apart, centre to centre and the bottom of the bars is 87mm from the bench top.

http://www.dm-tools.co.uk/product.php/s ... pLV-2ZnmfQ

 

[Popkorn]

Thanks, haven't seen this before, I will give it a good look.

 

[Chris152]

Mine came with one, just did a couple of shots for you. I've no idea what details you need, but happy to measure if you can say what you need to know. It's 53 cm long in total.

Chris

 

[Popkorn]

Hi Chris, outstanding. Any measurements you can provide would be great, width of arm, thickness, slot width, angle, angled length, length over bars, length from bars.
My son is a toolmaker (unfortunately in Canada) and has said he would make it up for me so any and all measurements would be helpful. I will send them plus your photos to him and he will take it from there, worry about shipping costs later, ha.
Thanks
John

 

[Chris152]

No problem John - I'll get onto it in the morning and post up as much as I can.

 

[Chris152]

John
Measurements are to the nearest mm (to the best of my ability!). Two problems - I don't have a protractor here to measure the angle, but maybe you can measure on the picture? - if not, tell me and I'll steal one back from the kids; I have no idea how to measure beyond the curves along the length! Maybe a bit of geometry will help with that? The total height (side view) is 90mm.
If the pics and details aren't enough to go on for either of these problems, I can trace the profile on paper and send it to you. Let me know if there are other measurements you need (the grooves to attach to the bars should be the same as the ones you already have on the bit that attaches to the bars).

C

 

[Popkorn]

Chris, again many thanks, I will pass on the dimensions to my son and see if he has enough info, anything else and I will come back to you if you don't mind.
Regards
John

 

[Chris152]

John - it occurred to me that he'll need this measurement, too:

that's the flange at the bottom of the hollow, into which the arm you already have clamps.
C

 

[Popkorn]

Thanks again Chris.

 

[roywathen]

I have one of these, I have no plans to use it and I might can sell it, what sort of price were you hoping to pay and how close are you to Tamworth, Staffs, regards roy

 

[Chris152]

Based on an assessment of that design I would be say it may not be all that rigid and stable.

I think you would be better off making a floor standing tool rest support, the tool loads will then be transmitted down into a solid support rather than trying to twist that cantilevered construct.

John - based on my limited experience (I'm just learning - this is my second attempt to use the extension) - Chas is not wrong. There is vibration through the setup as I have it. So I put a piece of pine in to see if it helped and it makes a difference, really solid now. I've not used a floor-standing rest so can't say if it'd be better, but I can't imagine it would. Hope that doesn't confuse things!

 

[CHJ]

My comments about going for a Floor standing Rest were on the assumption that if money had to be spent and/or time and effort put into making a rest.
I would then consider making a Floor standing construct easier, cheaper and ultimately as, if not more, flexible in usability.
I was aware that several commercial outrigger Tool Rests on larger lathes use a floor stay to add rigidity just as achieved with the wood stay.

 

[Popkorn]

Again thanks Chris, I will take on board both comments. Just waiting on a reply from a possible seller and if successful will experiment. Looking at your photo I can now see the concern, quite a length, and I can see the need for a support. Sorry for the delay in replying.