Re: [CAD_CAM_EDM_DRO] Flexible Couplers on Retrofit?

I assume you know about: http://groups.yahoo.com/group/hf47158toCNC/ ?

You could try to do a solid coupler, but by the fact that you asked, I
would guess you won't be happy with the results. You _really_ need to get
it perfectly aligned. The fact that commercial machines use flex couplers
tells us something.

Something quick and dirty, and on par with the accuracy of the machine is
to use a flexible hose between the motor and lead screw, and hose clamps on
both ends. Later if you feel it is a limiting factor, you can upgrade it.

Please read the above newsgroup. All sorts of good suggestions on how to
clean up your machine, eliminate friction, back lash, etc. Your motors
will be a bit small to do fast rapids (don't expect 20ipm), but the price
was right, and the xylotex driver will support bigger motors in the future.

- Steven Ciciora

At 02:26 PM 1/8/2004 -0500, you wrote:

>Todd, you need flexible couplers unless you want to break something - or
>unless you can (lathe) turn and mount parts with extremely high
>concentricity. Things will bind if they're out of alignment.
>
>If you're strapped for cash, why not consider using a slightly flexible
>material like a high durometer polyurethane rod and turn them out of
>that? You should still be able to drill and install set screws if you
>make the OD large, relative to your shafts. Quite honestly $20 a pop
>sounds pretty good to me! My 3 helical zero-backlash couplers for a
>Bridgeport sized mill set me back over a hundred each!
>
>Cheers, Peter
>
>Todd Meidinger wrote:
>
> >I am in the process of putting together a CNC retrofit Mill using a
> >Xylotex controller and NEMA 23 116 oz./in steppers from Jeff. I am
> >putting this on the $279 s axis machine that Central makes/sells. I
> >know for this price it can't be the best in the world but I am not
> >looking for that right now. I figure I am going to have just over
> >$500 into the entire setup when I am done. Get what yo pay for I
> >guess.
> >
> >Will I need flexible couplers from the steppers to the screw? I was
> >looking at flex couplers and they are about $20 a pop for the ones I
> >
> >
> >
>
>
>
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