Re: How to you make a 1/8" collet on a 1/4" shaft

also, check out your exacto and Dremel for possible store bought
collets.

Dave



--- In CAD_CAM_EDM_DRO@yahoogroups.com, "deansala" <adsala@p...>
wrote:

> Dave,
>
> Ok colleting the shaft end is a pretty good idea but...and I have
> thought of this..how in the heck can I guarantee that I can ream an
> 1/8" hole perfectly centered in a 1/4" shaft. I have have a pretty
> rigid lathe and have center drills, of course, but I have found

that

> sometimes my holes can get off center. At 30,000 rpms, this might
> produce vibes. Maybe you can suggest a lathe technique that will
> guarantee centerness of my hole. I guess I can use the same idea

when

> threading the shaft as well. Probably not as critical but may

lower

> vibrations.
>
> Thanks
> Dean
>
>
>
> --- In CAD_CAM_EDM_DRO@yahoogroups.com, "turbulatordude"
> <davemucha@j...> wrote:
> > I think the simple answer is to put the whole collet thing on the
> end
> > of your spindle.
> >
> > drill and ream for the 1/8 shaft
> > thread the OD for some fine thread
> > put a taper on the end of the shaft of 45 degrees or so.
> >
> > Make a nut with the same thread and also put a matching taper in
> the
> > nut.
> >
> > slit the shaft well into the threads.
> >
> > when you put the nut on, your nut will compress the taper locking
> in
> > your engraver bit.
> >
> >
> > another idea is to take a 1/2 dia block and ream it to be a press
> fit
> > on the shaft and make a collet end much like a router. these

can

> be
> > pretty simple to do, but you need access to a lathe.
> >
> > I made a few collets for my trim router and they came out pretty
> > nice. the drills did not spin in any material (yet) so I'm happy
> > with the do-it yourself collets.
> >
> > Dave
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > --- In CAD_CAM_EDM_DRO@yahoogroups.com, "deansala" <adsala@p...>
> > wrote:
> > > Hi everyone,
> > > I have not used this list in a while but when I did, I always

got

> > > great answers. I have a situation. My mill needs a faster
> motor.
> > So
> > > I rigged up a Dewalt Laminate trimmer motor to the top of my
> > > drawbar. I connected a 1/4 in shaft to the motor which runs

down

> > the
> > > drawbar hole(about 16" long). On the lower end (turret end) I
> > > installed a part that houses two high speed bearings in which

the

> > > shaft runs through. Now sticking out the very bottom of the

piece

> > is
> > > a 1/4" high speed shaft about 1-1/2" long which needs

colleting.

> > >
> > > The whole idea is so that I can CNC engrave using high speed
> > engraver
> > > bits. I need to some how attach an 1/8" engraver bit to the

1/4"

> > > shaft. What I need (I think) is piece that has a 1/4 female
> collet
> > > on one end and an 1/8 female collet on the other. It can not

be

> > more
> > > that a couple of inches long. I have tried boring 1/4" and

1/8"

> > > holes in some round stock and use set screws to attach to the
> shaft
> > > and mount engraver bit. I works ok but it's very hard to get

it

> > all
> > > true at 30,000 rpms!
> > >
> > > Any thoughts or better yet can someone make me the part I seek?
> > > Dean