Re: [CAD_CAM_EDM_DRO] Crazy Ideas Vol 1

Stephan,

For proximity sensors (limit switches) I use inductive proximity sensors fro
Automation Direct.

I sell a nice break-out board that is already set up to power the proximity
sensors. www.campbelldesigns.com

You may want to look at my web page. I am sure that there is something there
that may help.

----- Original Message -----
From: "Stephan Kotzé" <stephank@...>
To: <CaD_CAM_EDM_DRO@yahoogroups.com>
Sent: Tuesday, June 03, 2003 3:38 AM
Subject: [CAD_CAM_EDM_DRO] Crazy Ideas Vol 1


> Hi All
>
> Been busy with my first mill. I decided on a arch type ("fixed Gantry"
with moving table) after reading a book on high speed milling and high speed
mill design. Working volume is 300x300x300mm. This is no router as I expect
to do all metals including superalloys. I got bits and pieces from ebay and
is now busy with construction. I also did some FEM analysis for errors etc.
(I am a mechanical/production engineer). The drivers and steppers are
sorted, now the integration.
>
> First problem I face is leadscrews. I did not buy commercial units,
instead settling on normal M10x1.25 thread (cheap). I read on a website
(about optical equipment) about lapping these to give an accurate thread.
That is now done. Next problem is mounting them. I got a bicycle axis and
split this in 2, giving me 2 adjustable angular contact units. I noticed
that they did not run very smooth, and after investigation I saw that they
have a very rough torque nut. Setting up a Dremel and fitting these units
onto bearings, I ground them smooth and accurate (pictures available for
those that want to see). They now run extremly smooth even when overtorqued.
Next problem is the nut. I have seen various designs on the net for these,
but none to my satisfaction. The roller screw nut design in the files
section is very interesting and i think i will go for that. Problem is I do
no have my lathe yet, so I might have to settle for a Delrin or oil
impregnated Nylon nut, tapped long enough to take up any backlash.
>
> Couple of questions:
>
> Anyone have a recommendation for homing switches. They obviously need to
be fairly repeatable. (optical, mechanical)
>
> I need an idea for cheap bellows to protect the linear guides and
leadscrews
>
> Vol 2 will follow soon with ideas for DRO's
>
> Stephan
>
>
> ---