Re: [CAD_CAM_EDM_DRO] Re: My ballscrew / bearing block design.

> Also, Les mentioned to pin the shaft. I looked at pins and drills and
> realized that if you have a small shaft, say, 1/2 inch, you cannot put
> in a 1/4" pin. you remove too much of the shaft.
>
> of course a 1/8" pin is small and can shear.
>
> Is there any rule of thumb or formula ?
>
> And, then (mini rant) pins can be really expensive. a couple $$ each
> or you have to buy 50 for $5.00 to $10.00 bux.
>
>
> Dave

I have, yet again, tweeked my design a bit. I am still planning to do a
shrink/interference fit but the ballscrew will go all the way through
bushing and into the flexible coupling on the servo shaft. I'll put some
threads on for a locknut to hold everything together. It will basically
end up being a sleeve.

I stopped by the bearing store last night and, of course, the fancy
preloaded bearing pairs I picked out are only stocked in Germany. I
explained what I am trying to do and they are doing a little research to
find something similar. If I end up just getting normal bearing pairs
with no preload I will have to put a thin spacer between the outer races
and use the lock nut to set the preload manually. I think I have to mount
the bearings back to back instead of face to face for that too.

I went by the local steel yard and got 14" of 4" x 1.5" flat bar to make
my blocks out of so I am on my way now...

/M