Re: [CAD_CAM_EDM_DRO] Best ball screw prices? (was: Ball screw load ratings)

Hi
This about Ball screws prices, The cheapest source I foud is the MacMaster
Carr they have very nice prices on 5/8" and 1" diameter ball sacrews,
also the nuts are cheap.

I hope It helps someone
Regards
Luis

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Ing. Luis Arturo Rapso Brenes
Profesor Asociado
Subdirector
Escuela de Ingenieria Mecanica
Universidad de Costa Rica
San Pedro, San Jose, Costa Rica
Codigo Postal 2060

Tel: (+506) 207 5695/4548
(+506) 225 6052 (Domicilio)
fax: (+506) 207 5610
Email Lrapso@...
Larapso@...
Lrapso@...

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

On Wed, 7 Mar 2001, Jeff Swayze wrote:

> Well, after further review I agree completely. I've decided to buy
> the Thomson Saginaw 5/16" .200 lead ballscrew and the preloaded ball
> nuts.
>
> Does anyone have a source whose price is significantly (5%+) less
> than Thomson's? All I found so far is Reid Tool, and they're a few
> cents cheaper.
>
> Thanks,
>
> Jeff
>
> --- In CAD_CAM_EDM_DRO@y..., Jon Elson <jmelson@a...> wrote:
> >
> >
> > Jeff Swayze wrote:
> >
> > > I'm in the process of choosing a ball screw (or lead screw) for a
> CNC
> > > retrofit of my mill/drill. Can anyone suggest a value for the
> maximum
> > > axial load such a ball screw would see? I would think only 100
> lbs.
> > > or so, but I really have no idea.
> >
> > On my small Bridgeport, the servo drives for the X and Y axes can
> develop
> > 1000 Lbs of linear force at stall. You can figure out the forces
> involved
> > in cutting operations by converting motor HP to torque applied at a
> radius
> > at some speed. For low speed operations with larger diameter
> cutters, the
> > linear force applied to the workpiece becomes substantial.
> >
> > > If the value is low enough I can use a modified acme screw with an
> > > anti-backlash nut (up to 125 or 250 lbs. depending on the style)
> and
> > > will save much $$. Otherwise I'll have to go with a ball screw and
> > > preloaded nut.
> >
> > I wouldn't try this. You will have very rapid wear of the nut and
> screw
> > if you try to preload an Acme screw. An adjustable but locked Acme
> nut
> > will work for a while, but eventually the central part of the screw
> will wear
> > so that it is looser in that region.
> >
> > I would think that a screw designed to hold at least 500 linear
> pounds of
> > force without bowing would be the minimum on your machine.
> > You need to keep in mind this includes table friction, inertia,
> cutting loads
> > all summed together.
> >
> > Jon
>
>
> Welcome to CAD_CAM_EDM_DRO@...,an unmoderated list for the discussion of shop built systems, for CAD, CAM, EDM, and DRO.
>
> Addresses:
> Post message: CAD_CAM_EDM_DRO@yahoogroups.com
> Subscribe: CAD_CAM_EDM_DRO-subscribe@yahoogroups.com
> Unsubscribe: CAD_CAM_EDM_DRO-unsubscribe@yahoogroups.com
> List owner: CAD_CAM_EDM_DRO-owner@yahoogroups.com, wanliker@...
> Moderator: jmelson@... timg@... [Moderator]
> URL to this page: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO
> bill,
> List Manager
>
> FAQ: http://www.ktmarketing.com/faq.html
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
>