Re: [CAD_CAM_EDM_DRO] Re: Making your own Ball nuts

Yup Tim, something like that.
Fortunately a little goes a long way.
And hopefully cheap compared to several
ballnuts.

I did talk to the Super alloy manager some.
He said it ought to work pretty well on 2-c acme thread
forms but their experience was all with ballscrews.
At least on the acme you don't have any rolling burr
to remove so that is a plus.

It will be too tight without sufficient mold release so yes
that is an important step. Any mold release compatible with epoxies
should work but I would go for a running clearance of 0.0005"
to 0.001". Has to have room for an oil film and accommodate
the slight pitch variations in the screw. Seems to me it would
be good if you could somehow get a thicker mold release coating
on the top and bottom of the thread as those surfaces do not
contribute to thrust loading. I also wonder if you could grind
a rough longitudinal groove in a waste end part of the screw to
use as a temporary minimal tap to fine adjust the cast nut
by shaving it slightly if needed.

And I will mention the M word.... Moglice! It is very similar to
our product. Good stuff. We always try to be a little cheaper
and provide better customer engineering support. Heh... I
should say I because ITW (Philly resins) is my client now rather
than my employer. I don't make anything for selling their goop.
Just designing their encoders.

With oil or grease lube the material is good to a surface speed
equivalent to 1000 rpm on a 1" diameter screw. Beyond that
close fitting polymer bearings can get hot due to their low
thermal conductivity.

Les
Leslie Watts
L M Watts Furniture
Tiger, Georgia USA
http://www.alltel.net/~leswatts/wattsfurniturewp.html
engineering page:
http://www.alltel.net/~leswatts/shop.html

----- Original Message -----
From: "Tim Goldstein" <timg@...>
To: <CAD_CAM_EDM_DRO@yahoogroups.com>
Sent: Friday, October 18, 2002 3:03 PM
Subject: Re: [CAD_CAM_EDM_DRO] Re: Making your own Ball nuts


> The Philly resin is something like $65 for the small container and then
> another $20 or so for the release spray if I remember correctly. If you go
> with it the release spray is a must as it controls the clearance as well
as
> acting as a release agent.
>
> Tim
> [Denver, CO]
>