[Gregted]

Annealing a piece of sheet aluminum is not easy because it is difficult to heat it evenly and often it will warp due to the uneven heating. But it may not be needed, your piece may be soft enough. If it is thin enough and soft enough to spin you will be able to bend a corner very easily with just a pair of pliers. If you have to really put in a lot of effort and/or the material cracks with a sharp bend then it is not suitable for spinning.

I suppose if it is too hard and you have a self-cleaning kitchen oven you could stick it in the oven during the cleaning cycle. That is just about hot enough to anneal most alloys.

Thanks for the info Geof,

The sheet is very thin and easy to fold/bend so it may be ok. I guess I will know soon enough. I have enough to cut 6 or so circles about 400 mm diameter so I have some to waste.

The main problem may be that the little piece of gal sheet I tried the other day seemed to come loose between the block in my headstock and the smaller block in my live center.

I was only using the back of one of my wood lathe tools though and it doesn't have a wheel on the end like I have seen so I may have to make another tool also.

My headstock on my wood lathe can rotate 90 degrees to allow much larger blocks of wood to be turned for large bowls etc and this allows the headstock to flex up at the pivot point so I may have to brace it down to the bed.

I also have to make a faceplate for my tail-stock and mount a bearing to allow it to rotate so I have a way to go but still an interesting concept.

Greg

[Geof]

.....The main problem may be that the little piece of gal sheet I tried the other day seemed to come loose between the block in my headstock and the smaller block in my live center......

See if you can devise a way to have a very strong but short spring inside the block on the live center. This way you compress the spring so it maintains the clamping force even if things move slightly. Big metal spinning lathes often have hydraulic cylinders holding the tailstock in.

The clamping action between the tailstock and headstock is where regular lathes fall short. They are not designed to apply really large forces.

[Gregted]

See if you can devise a way to have a very strong but short spring inside the block on the live center. This way you compress the spring so it maintains the clamping force even if things move slightly. Big metal spinning lathes often have hydraulic cylinders holding the tailstock in.

The clamping action between the tailstock and headstock is where regular lathes fall short. They are not designed to apply really large forces.

Thanks Geof that's a great idea.

I've got some valve springs that will be perfect for the job.

Tried some disks tonight but no good. The first one seemed to start to form to my mandrel but folded on itself and cut the center out and the second disk just cut at the edges of my form.

I might start with a larger hardwood form and round the edges to make a much easier shape to mold at the start.

I made a roller tool with a roller blade wheel between two pieces of steel and welded these onto a length of pipe but it didn't help.

When I work out how to attach pics, I will do so.

Thanks again for the great advice so far.

More to come.

Greg