Re: [CAD_CAM_EDM_DRO] Re: ground plates ( alternative?)

Dave, what kind of rails are you using? How long?

For z I used hot rolled 1018 bar stock scraped in as mentioned
in that file I posted. They were too long for my surface grinder.
Hot rolled has much less stress than cold rolled. It was
stress relief heat treated when it was rolled!

If your rail bearings and the carriage they are on are stiff enough
you wont need a big plate for z. The rails and their stiffeners
will resist twisting moments. You could mostly have air in between.

If you need more stiffness than that a closed hollow cross section
will have many times the torsional resistance of similar sized angle,
I beam, or channel.

If you tell me what you have or want I can do a quick stiffness calc
for you.

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

----- Original Message -----
From: "turbulatordude" <davemucha@...>
To: <CAD_CAM_EDM_DRO@yahoogroups.com>
Sent: Wednesday, July 10, 2002 9:22 AM
Subject: [CAD_CAM_EDM_DRO] Re: ground plates ( alternative?)


> Hi guys,
>
> seems this can get a little OT, but since I assume that anyone making
> a Z axis would need to have flat and paralle surfaces, it does fall
> into the intent of the list.
>
> I had planned on using a pair of said plates to mount my rails on.
> The flatness would eleminate any power robbing misalignment.
>
> Is there a better way ?
>
> Is that square aluminum extrusion with T slots ( not sure of a name
> for it) stiff enough to handle a thin sheet metal cutting router ?
>
>
> Dave
>