Turning long heavy piece

[gasman]

Hello chaps
I am an occasional turner and, as part of a set of fancy library steps I am making, I need to turn a cylinder 60mm diameter in sycamore and about 1500mm long. The only way I can think of to do it is to do it is 2 halves and then join them as the supporting 'rollers' I have seen described would presumably not cope with the weight. Any ideas?
Thanks a lot
Mark

 

[paulm]

As you suggested Mark, done in two sections with a round tenon and mortice to join and glue after ?

Cheers, Paul

 

[AndyT]

Assuming you mean a plain cylinder of uniform diameter, you could forget the lathe and treat it as an exercise in planing on the bench. Plane a length of your chosen timber to 60mm square, then remove the arrises to make it octagonal in section, then take those corners off so it's sixteen sided. Finally smooth over with a hollow plane - a number 14 would be about right and need not be expensive. Alternatively, go through the grits with sandpaper, maybe held onto a bit of something concave such as an offcut of plastic guttering.

 

[gasman]

Many thanks both of you - yes both good ideas and I think I might just do it by hand as I think it will end up being quicker
Best regards Mark

 

[AndyT]

Just a thought if you do go for the planing option - there is a boatbuilder's tool known as a spar gauge, which marks the lines for planing a square to an octagon, even if the work tapers. It might be worth making one - they can be very simple. There was a discussion about them here: https://www.ukworkshop.co.uk/forums/spar-gauge-t47534.html. I suggest that one with pens or pencils would be more suitable than one with pins.

 

[gasman]

Thanks Andy - I actually think it will be fine on my table saw with the blade at 45 degrees to get it close. I was worried about cutting 2 lengths of an 200mm board - but I cut 70mm off each side and neither moved at all. Then I glued them up and it is very straight and true and about 68mm square at the moment. So I think this timber is very dry (been inside for years) and has no internal stresses. I might even change the plan and make it octagonal rather than round. You are kind to offer such helpful advice
Mark

 

[AndyT]

You're welcome! But speaking as someone with a bit of a thing for library steps, I do hope we get to see the finished project.

 

[gasman]

Thanks Andy - here's the sketchup plan.... I may need to add some weight (lead) to the bottom to add stability. This is what the 'client' agreed (my father-in-law). It stands 1500 tall, each step is 200mm and the steps are each 33 degrees, 30mm thick and 480mm long
It will have an ebony 'ball' on top and black inlays in the steps as shown

Regards
Mark

 

[Inspector]

If you have a bench lathe you could take the tailstock and mount it to a block further along the bench. A simple tool rest to move along as you turn clamped to the bench, or a long one full length, made of hardwood or angle iron completes the rig.
Pete

 

[gasman]

As requested - picture of (almost) finished library steps... Done in sycamore with ebony inlays.
The pole came out well. I glued up 2x 1500mm pieces, cut it square to 65 x 65mm, then made it octagonal, then 16 sides, then 32, then I had a moment of inspiration - due to not having a 5 foot long lathe bed. My lathe is a very heavy old coronet major - so I drilled a 6.5 mm hole in the end of the pole, then screwed a 6mm short bolt with the end cut off into the wall at the same height as the lathe spindle. Then mounted the pole and had it turning on the slowest speed. It was quite stable so I just sanded it - starting with 80 grit and ending up with 600 - it worked very well. The ebony ball I made from some odd pieces of 32x32mm, glued up with CA glue, then turned very slowly using a cardboard semicircle as a guide.
Here's the lathe setup

And the ball:

And here are the steps virtually done - a couple more coats of hardwaxoil needed

Comments welcome - thanks for looking
Mark

 

[woodfarmer]

Looks really good. Love the way you overcame the problem :

Years ago I turned several staffs. about 5ft 6 long. It was easy as unlike all the wood turning lathes the Holbrook has a hollow spindle. The lack of which is a a real failing on wood lathes.