[Metal lathe] Indexing plate and cranck

[Christophe Mineau]

Hi,
I needed something to index the spindle of my metal lathe, and I decided to build it, adding the crank feature. I wanted something not too much intrusive and that would be quickly mounted / unmounted as needed.

Here is what I came up with :









And here is how I did it :

First the plate, continuing on my idea to source metal in the kitchen utensils, it is made from an induction interface plate. I initially thought it would have been made of plain stainless steel, but I discovered when drilling through it that it is actually principally made of aluminum, coated with stainless steel sheets on both sides. Anyway, this is good enough for me, it is 5mm thick.
The shaft is turned out of aluminum round stock, and will be inserted in the spindle (21 mm on that side).


The shaft is cut at 45° using the table saw. Wood cutting tools work well for aluminum.
I don't remember who gave me this idea for locking the shaft in the spindle, I think it's here, maybe Paul Jones.
It works very well and is really much easier to make than an expending system.


The plate is screwed on the shoulders of the shaft.
On the right you can see the beveled bottom part of the shaft. The inside bore is threaded and a piece of threaded rod will be used to pull it and lock it.




For drilling accurately the indexing holes, I drew a two pieces template with my
CAD software.


It was initially planned only to be a template but I left it glued on the plate actually and varnished it to protect it from dirt.


The crank knob, wood turned out of beech. I inserted a brass sleeve in it to ease the rotation of the knob around the screw.


Finished Verso. The brass pin will be inserted in a small block of steel screwed on the lathe body.
The tip is threaded M4 and the shaft has a 5mm diameter.


Finished Recto :

[C-Bag]

great project, great documentation!

I feel another "tool of the week" coming on........

[sking0369]

Nice work there but I'm not understanding what the shaft cut at 45 is for?

[scrdmgl]

The cut at 45 Deg., allows the short piece to slide when the bolt at the end is tightened and locks to the spindle ID holding the whole assembly in place. Simple and effective.

[Christophe Mineau]

The cut at 45 Deg., allows the short piece to slide when the bolt at the end is tightened and locks to the spindle ID holding the whole assembly in place. Simple and effective.

Yes, that's exactly it, quick and easy solution !
Thanks

[rustybeast]

I'm just a regular looker. Lots of great ideas.
Thanks, Dave

[Karl_H]

The cut at 45 Deg., allows the short piece to slide when the bolt at the end is tightened and locks to the spindle ID holding the whole assembly in place. Simple and effective.

This is the same mechanism used to position the handlebars on a bicycle - at least on the ones I had as a kid.

[axgold]

Nice work there but I'm not understanding what the shaft cut at 45 is for?

I was wondering the same thing and guessed it must be to wedge the shaft in the arbor hole maybe?

[basalt]

Nice work there but I'm not understanding what the shaft cut at 45 is for?

When the 2 pieces cut at 45 degrees are drawn together they expand inside the spindle and jam.

[mklotz]

When the 2 pieces cut at 45 degrees are drawn together they expand inside the spindle and jam.

Works equally well for square stock; handy for something that needs to lock into a square-sided slot.