Re: [CAD_CAM_EDM_DRO] Re: small spindle ?

Jeff,

I don't believe the motor used in those spindles is the same type as a battery powered drill.  Why would they be?  The bearings in any high speed spindle, small trim router motor, or a rotary tool such as the Proxxon are going to be radial bearings.  Radial bearings are specifically called for when side loads are high.  I suspect the bearings in the spindle in question (in the link) will last as long as the quality of the bearings used not the type of motor.  


However .0015 runout is pretty high for a spindle.  It would have to be made pretty poorly to have that much runout.  I can tune a drill press with a hammer and get runout  that good (or  poor).  It's probably good enough for a hobby machine since it's too small to measure with most calipers.   I suspect the poor runout specified is the result of the chuck used, not the motor bearings. 


Any idea what the runout of a trim router would be?  Probably pretty low until the chuck is added.  I would think that even a collet like the PreciseBits would be fairly difficult to mount to a router without increasing the runout.  Seems to me that the only way to get precision for cheap would be a belt driven spindle.  That would take the runout of the motor out of the equation. 


ljg



 
Larry Guthrie
yrralguthrie@...
larry.guthrie@...


________________________________
From: Jeffrey T. Birt <birt_j@...>
To: CAD_CAM_EDM_DRO@yahoogroups.com
Sent: Thursday, June 7, 2012 7:30 PM
Subject: RE: [CAD_CAM_EDM_DRO] Re: small spindle ?


 
The type of motor used in the spindle that was linked to is the type that is
used in things like battery powered drills. They are designed to power a
gear train, they are not made to have a cut down ER11 collet chuck mounted
to them (i.e. the bearings/bushing will not hold up.)

One very economical way to have a good spindle for a home built machine is
to use a small trim router motor with precision collets made by PreciseBits.
I dare not provide a link else I'll get in trouble with the moderator again.

Contact me off list at birt_j@... for more information. I don't
like not being able to share openly but when I do I get bawled out.

Jeff Birt

Soigeneirs.com

From: CAD_CAM_EDM_DRO@yahoogroups.com
[mailto:CAD_CAM_EDM_DRO@yahoogroups.com] On Behalf Of LJG
Sent: Thursday, June 07, 2012 4:16 PM
To: CAD_CAM_EDM_DRO@yahoogroups.com
Subject: [CAD_CAM_EDM_DRO] Re: small spindle ?

Jeff,

Where would I go about getting a motor-spindle with less runout than
.0015". Most lathe chucks under $1000.00 don't quarantee runout less than
about .002".

When you say "those types of motors" what did you mean?

I'm a newby and building a machine and want to use quality components.

ljg

--- In CAD_CAM_EDM_DRO@yahoogroups.com
<mailto:CAD_CAM_EDM_DRO%40yahoogroups.com> , "Jeffrey T. Birt" <birt_j@...>
wrote:

>
> Honestly, 0.0025" or an inch is a HUGE amount of run out. Even the

'premium'

> spindle is only quoted as 0.0015" which is also a HUGE amount of run out.
> Those types of motors are likely not designed to take and side load

imposed

> by cutting so the bearings will likely not last very long.
>
>
>
> Just my 2 cents
>
>
>
> Jeff Birt
>
>
>
> From: CAD_CAM_EDM_DRO@yahoogroups.com

<mailto:CAD_CAM_EDM_DRO%40yahoogroups.com>

> [mailto:CAD_CAM_EDM_DRO@yahoogroups.com

<mailto:CAD_CAM_EDM_DRO%40yahoogroups.com> ] On Behalf Of Bob

> Sent: Monday, May 14, 2012 1:04 PM
> To: CAD_CAM_EDM_DRO@yahoogroups.com

<mailto:CAD_CAM_EDM_DRO%40yahoogroups.com>

> Subject: [CAD_CAM_EDM_DRO] Re: small spindle ?
>
>
>
>
>
>
>
> Take a look at this.
> http://www.zentoolworks.com/product_info.php?cPath=16
> <http://www.zentoolworks.com/product_info.php?cPath=16

<http://www.zentoolworks.com/product_info.php?cPath=16&products_id=122>
&products_id=122>

> &products_id=122
> cheers
> Bob
> http://www.cad2gcode.com/cncprojects/
> --- In CAD_CAM_EDM_DRO@yahoogroups.com

<mailto:CAD_CAM_EDM_DRO%40yahoogroups.com>

> <mailto:CAD_CAM_EDM_DRO%40yahoogroups.com> , "turbulatordude"
> <dave_mucha@> wrote:
> >
> > Hi all,
> >
> > looking to fabricate a very small bench top machine. looking for a small
> spindle, something low cost.
> >
> > I would like a spindle like a Dremel Flex shaft, alas, a friend burnt
> through half a dozen over a year. was he just unlucky ? is there a problem
> cooling or should he have oiled the bearings ?
> >
> > This will be for a very light duty machine. weight is an issue, I do not
> want to use anything as big and bulky as a dremel. and I would prefer to

not

> make one.
> >
> > that is what I would like... now the reality has to come in. any
> suggestions ?
> >
> > the machine is going to be made of 1/2 inch plastics. I got am getting a
> lot of scrap that I can put to use.
> >
> >
> >
> > Dave
> >
>
>
>
>
>
> [Non-text portions of this message have been removed]
>

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