An improved simple indexer

[Macca]

Based on Signal Failure's post http://www.homemodelenginemachinist.com/index.php?topic=2869.0
I started off by hacking off a bit of 40mm aluminium and turning it down to be a sliding fit in the spindle bore.

Then I flipped it over and turned it down to fit the bore of the change gears that came with my lathe, and whacked an 8mm hole through it.

I slotted the spindle end with a hacksaw,

and filed a keyway and matching key.

I tapped an 8mm thread in a bit of 10mm mild steel, turned a taper, then loctited in a bit of 8mm threaded rod.

All together:

The frame is just some aluminium angle riveted together, with a block of aluminium bolted on to hold the detent.

The detent is just a piece of 10mm mild steel, turned down for a section to fit a spring, and filed to match the shape of the gear teeth.

Here it is set up and in use:

It is worthwhile noting that my lathe has a safety interlock, it can't run if the cover is open, you can see the switch just to the right of the small pulley above.
Nevertheless, it is a good idea to unplug machines whenever they are used manually, it is just too easy to make a mistake.

 

[bentprop]

I like it!Simple and effective.Give that man a cigar ;D

 

[tel]

Yep, that's 'ow it's done, except I used the guts out of a masonry anchor for mine - saves all that malarky with the taper and the threaded rod

 

[Lew Hartswick]

> I used the guts out of a masonry anchor for mine - saves all that malarky with the taper and the threaded rod<

Now THERE is a gem of an idea. A ready built expanding arbor.
Thanks.
...lew...

 

[max corrigan]

And also if you use the rawelbolt bolt type of masonary fixing the taper cannot turn when you tighten it up in the spindle the taper part is either a hexican shape or has little ears that pick up in the main bodypart, the taper might turn on Maccas tool! but could be overcome not that easily by putting a pin in the taper and letting it run along one of the grooves in the expanding sleeve it would have to be a pretty small pin though

Tel
that indent part of the tool you have fixed on your lathe (ML7)is a permanent fixture ie bolted on cause im am thinking of doing the same thing on my old Super7

Macca
i am not knocking your design, it is great! just pointing out what could happen, as i made a hand crank for the spindle of my lathe and without the pin (the taper was longer than yours and the slots wider, i used a 3/32 roll pin)the taper would roll when you tightened up and loosened, good design tho i will definately put on my list or "heap" as it is from this site
Regards Max.........

 

[Macca]

I did think of using a masonry anchor, thats where my idea came from. The only problem was I didn't have one small enough.
Max, I used a lot of loctite on the taper/rod, it hasn't slipped yet. I did think about pinning it but I wanted to use it straight away, so I didn't bother.