Re: My ballscrew / bearing block design.

I was at the bearing store looking at the 15mm bearings and they
just looked small. I used SKF's online calculators and the smaller
bearings seemed like they would work but bigger is always better ;).

I was also reasoning that it might be slightly easier to machine the
required parts if the diameters were a bit bigger. The 20mm bearing
matches the original one in the mill too.

I like the sleeve idea mentioned below. I had a sleeve in one of my
design iterations but it got evolved out...there's not much
intelligent design going on here ;). Looking at the cross section
pic it is making more sense again. It was late lastnight when I
finished up...

One of my design goals was to come up with parts I could buy or make
on my 13" lathe. It's a catch-22 when you pull your mill apart to
measure things so you can make new parts for it. I want to make the
bearing block out of steel but I need to source 2 pieces of 1.5"
thick plate some where. I figured I could make a weldment out of
the motor mount piece and then machine it.

/M


--- In CAD_CAM_EDM_DRO@yahoogroups.com, "PPC" <pharmapack@s...>
wrote:

>
> I am no expert on this but looking at your website and perusing

Hiwin's

> catalogue, here are some info that hopefully will be useful:
>
> 1) Your ballscrew diameter of 3/4" is about 19 mm.
> 2) You were saying that you felt using a bearing of 15 mm ID maybe

too

> small.
> 3) Looking at Hiwin's spindle end dimension for 20 mm ballscrew,

they

> recommended using bearing 7302BTVP or 6202 for 15 mm spindle end.
>
> So, maybe it is safe enough to use bearing with 15 mm ID and no

need to go

> thru all those troubles.
>
> Weedy
>
> ----- Original Message -----
> From: "Tony Jeffree" <tony@j...>
> To: <CAD_CAM_EDM_DRO@yahoogroups.com>
> Sent: Monday, November 07, 2005 2:37 PM
> Subject: Re: [CAD_CAM_EDM_DRO] My ballscrew / bearing block design.
>
>
> > At 06:33 07/11/2005, you wrote:
> >>I spent the past week or so working on a bearing block design

for my

> >>conversion. I am documenting my project on

http://www.cncwright.com

> >>and I put some screen shots up. I got ballscrews that were only

3/4"

> >>in diameter and have been trying to figure out a way to mount

them in

> >>bearings bigger then 15mm ID. I am thinking about shrink-

fitting an

> >>adapter on the end of the ballscrew that will also me to make the
> >>diameter bigger. I'm not too sure about shrink fits and would be
> >>interested in any tips, information, or alternate ideas.
> >
> > Alternatively, why not:
> >
> > - Sleeve the ID of the bearing; or
> >
> > - Use smaller bearings?
> >
> >
> > Regards,
> > Tony
>