Re: Sherline Auto Tool Changer

Peter,

I like those holders as well, but I change 'em manually. I HAVE
thought some about how to automate the process, tho...

I feel these simply won't reliably work in an auto tool changer.
Here's why. It's relatively easy to set up for putting one of these
ON the spindle. (Presenting the holder and using the spindle motor to
wind it on...) BUT... It's getting the old one OFF that is
problematic, IMO. First, it is going to take more torque to get it
off than was used to put it on; and this just takes into account the
friction of the mating faces of holder/spindle. BUT, we also have the
tightening effect of the cutting forces while the tool "was" used.

Roland Friestad mentioned something to me a couple years ago, about
turning the HOLDER instead of the spindle (We were talking about
mill/drills at the time, and how to line up an r8 holder with the
anti rotation pin in the spindle). So maybe using an air wrench could
work? BUT... the size doesn't seem likely to work, and interference
issues would greatly restrict the available travels, if you could
find room.
I have worked out some details for doing it this way, but it ends up
pretty Rube Goldberg-ish.

If we look at tool changers of similar size on other tools we find ER
type holders (or some other type of non-locking taper-ed holders).
This is because their non-locking nature solves the problem of
getting the old tool OUT, described above.

So I'm leaning towards accepting that the only real solution is a
clone of one of these existing types... (Which may not be that
tough<G>)

Hope this helps,

Ballendo


--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Peter Cruickshank
<crankshaft_sg@y...>" <crankshaft_sg@y...> wrote:

>> What I have in mind is to use the Sherline End Mill Holders
> (http://www.sherline.com/3079pg.htm) as the quick change tool
> holders and somehow have a carousel off to the side which offers

the

> tools up to the spindle, removes one and replaces with another.
>
> Not as simple as that I know, but in my mind it seems a bit easier
> than the EMCO approach.
>
> I'd like to see some pics, diagrams etc of these robo drills if any
> one has them, maybe that will give me some inspiration !
>
> Regards
>
> PeterC
>