# Making a new Dial Indicator Crystal



## Mcgyver (Jun 1, 2022)

Here's a video I just put up on making an new crystal for a dial indicator.  I usually just buy watchmakers crystals for a few dollars from ebay, but they are not available in sizes this large.  I ended up making a rotating tail stock pressure plate that worked well, more effort than the indicator warranted but hopefully it sees additional use.  This video should be 5 minutes but somehow I droned on for almost 17.  And thats with a lot left on the cutting room floor.....the editor needs a stern talking to.    Making a slick video is lot harder than it looks!


----------



## David_R8 (Jun 1, 2022)

That's very well done!


----------



## John Conroy (Jun 1, 2022)

Nicely done! Thanks for taking the time to document that.


----------



## trlvn (Jun 1, 2022)

Great video!  One minor curiosity for me, though...at around 5:13, it seems like the 'live centre' isn't running very concentric with the headstock side.  Given your design, I don't understand how that could be?






Otherwise, very much enjoyed seeing something new!

Craig


----------



## Mcgyver (Jun 1, 2022)

trlvn said:


> Great video!  One minor curiosity for me, though...at around 5:13, it seems like the 'live centre' isn't running very concentric with the headstock side.  Given your design, I don't understand how that could be?



Thanks Craig. 

I noticed that too.  The press of the bearings on the shaft worked out well, and centre hole and OD were turned at the same set up so thats not it.    The bearing outer race bore might be a bit responsible, being kind of quick and dirty work I just reamed rather that 10ths single point stuff....so there could be a bit of wobble there, but it can't be that much.

I think what it is, is that the whole rotating pad ends up not perfect inline with the lathe's axis.  The rubber is so soft and grips so well that when you apply pressure with the tailstock, it could easily be off kilter a bit.   I'll do a test and press the metal flat surfaces together, if the wobble went away that would explain it


----------

