I blame Roy Underhill!

[AndyT]

Andy,
As I've spent rather a lot of time on metalwork this year I also thought I should get back to some woodwork so I have made a start on making a mandolin, which will be a new adventure for me. Incidentally, before I got a woodturning lathe I did some woodturning using the Barnes, including making two start barley twists with a small router strapped to the carriage and the gear train set to deliver the required pitch. This Heath Robinson type idea worked quite well although the twists did need some finishing by hand.

Now that sounds clever...I don't suppose you took any photos?

 

[bugbear]

Andy,
As I've spent rather a lot of time on metalwork this year I also thought I should get back to some woodwork so I have made a start on making a mandolin, which will be a new adventure for me. Incidentally, before I got a woodturning lathe I did some woodturning using the Barnes, including making two start barley twists with a small router strapped to the carriage and the gear train set to deliver the required pitch. This Heath Robinson type idea worked quite well although the twists did need some finishing by hand.

Now that sounds clever...I don't suppose you took any photos?

It's normal screw cutting, same as you'd do to make a big wood screw for an old fashioned vise.

http://www.woodworkforums.com/f152/wood ... se-131710/


Again, the mandrel handle would be a useful adjunct.

EDIT; For very coarse threads turning the lead screw directly, and allow the lead screw to drive the mandrel is better.

BugBear

 

[AndyT]

Thanks yet again BB - my list of possible projects gets ever longer!


That all looks practical and possible. Maybe a bit noisy, but it would also be possible to set up a v-cutter, held in the toolpost, to cut a thread the way you would with a screw box. The big advantage would be that, with the lead screw controlling the rate of advance, you could take successively deeper cuts. You can't do that with a box, as you need a section of complete thread to engage with the existing thread at the back of the box.

Food for thought indeed!

 

[bugbear]

Thanks yet again BB - my list of possible projects gets ever longer!


That all looks practical and possible. Maybe a bit noisy, but it would also be possible to set up a v-cutter, held in the toolpost, to cut a thread the way you would with a screw box. The big advantage would be that, with the lead screw controlling the rate of advance, you could take successively deeper cuts. You can't do that with a box, as you need a section of complete thread to engage with the existing thread at the back of the box.

Food for thought indeed!

V cutters are famously tricky to sharpen; I wonder if something like a #735 twin blade grooving arrangement is possible?

(personally I'd go with the noise)

BugBear

 

[AndyT]

Alas, my only 735 lacks the twin blade grooving attachment! I must be more careful with my future purchases. ;-)


Possibly the principle could be adapted. But then I do have a Beale 60° cutter and a small,easily clamped electric router...

 

[Richard T]

Very interested in your slot cutting Andy - what are the teeth like on that thingy?

 

[AndyT]

Very interested in your slot cutting Andy - what are the teeth like on that thingy?

They are just like short stiff bits of hacksaw blade but with the advantage of coming in a selection of thicknesses so you can make a slot in one cut without faffing about trying to widen a thin sawcut. It cuts on the push stroke.

Fairly common on eBay which is where this one came from. Not to be confused with the similarly named offering from Apple, which versatile as it is doesn't do Slitting, Slotting, Scraping or Sawing!

 

[dickm]

Dick
Yes, the possibility the errors might stack up too much is a concern. However I have checked the adaptor in place on the Arundel with a dial gauge and it is running reasonably concentric but of course the real test will be how the chuck runs when fitted …..

Glad to hear it worked. Either you are a very lucky/very skillful guy, or your 3-jaw is well above normal accuracy!
Have to confess that the only way I've managed to get really accurate adaptors for the Mystro relies on the fact that it and Super 7 have the same nose thread. So once the internal thread is done, it can be fixed directly on to the Super 7 nose and the external thread and register almost have to be right. Only worry is if one day, an adaptor tightens itself on to the Super 7 nose and won't come off.................

 

[rxh]

Thanks Dick,
It's good luck, I think, plus a good 3-jaw (it bears the proud markings: The Crown Chuck, made in England).

Andy,
'Sorry, I have no pictures of my arrangement but it was rather like that shown in BB's link. I used the central part of a very old B&D 1/4" router with a round nosed bit. Of course it was a very noisy and dusty process. I made twisted columns for the sides of a clock case - one right handed and one left handed. Unfortunately I can't find a picture of the finished job but here is a photo of the test piece I made first to try out the procedure.

Another thing I fancy trying sometime is making a clock with a wooden mechanism - using the router on the lathe again with a suitably shaped bit to cut the gear teeth. An indexing plate will also be needed.

 

[rxh]

I have made this mandrel handle following the suggestion by BB. The turning was mainly done by hand using a 1/2" HSS woodturning scraper, running at about 700 rpm. Andy, I think this technique would work well for you for making a permanent replacement for your broken handle.

 

[AndyT]

If I can make something as tidy as that I will be very pleased!

I have been
looking in various books and YouTube videos for information on contour turning and have found almost nothing on how to do it by hand. Several videos on ball turning with a special attachment but after that it's CNC all the way. I have managed to turn a ball tip on the end of some 3/8" rod by cutting a groove and then enlarging it with files and rounding over the free end.

I shall now give scraping a go as well - I have a good strong Sorby scraper with carbide tips which might be suitable.

 

[xy mosian]

Andy, I am not sure if you have come across this:- http://www.scribd.com/doc/77649397/manu ... 00watsrich.
"Manual of the Hnad Lathe", the first chapter deals with the foot lathe.
There is a wealth of skill on display daily on these forum, not least in this thread. Keep up the good work.
xy

 

[AndyT]

Thanks Xy, that's one I'd not found. I especially liked this statement on p 16:


"There is no family in this country that would not find it economy to have a foot lathe in the house where the members have mechanical tastes - not necessarily the male members, for ladies use foot lathes, in Europe, with the greatest dexterity."

 

[xy mosian]

Andy, I had missed that statement but I quite like it.
xy

 

[DTR]

I have made this mandrel handle following the suggestion by BB. The turning was mainly done by hand using a 1/2" HSS woodturning scraper, running at about 700 rpm. Andy, I think this technique would work well for you for making a permanent replacement for your broken handle.

Nice handle, how does it mount to the spindle?

 

[rxh]

Thanks Dave.
The spindle has a projecting key that engages with slots in the gear wheels. I made the handle with a similar slot.

 

[jimi43]

Boy did I miss a great thread...and am I pleased to be coming to it now.

Sorry I wasn't around Andy when you asked the question about the degreaser...bit late now but Liquid Engineering asked me to do a review of another of their products...which was their degreaser!!! I still have it to test and could have sent it to you as I didn't have anything to degrease at the time but I think it's too late now!

You have done a wonderful job so far and in particular...your skill at screw turning clearly shows you have the knack for it! Great stuff indeed.

I am at work at the moment but want to go back and read this more carefully...it is a great journal!

Jimi