Re: Creating long straight edges

I've been thinking about a method that is a variation on your
method. What do you think about it? ...

Place the rails on the support beam. At one end of the rail, place a
cheap laser pointer and at the other end, place a detector ciruit
with some audible feedback. Make three identical (relatively)
placards and create the smallest hole possible (end of needle?) in
each of the placards. Place one of the placards in front of the
laser and one in front of the detector. Securely affix the third to
the bearing surface that rides on the rail.

Move the bearing along the rail and shim wherever the light is
blocked. Now, if there exists a material that could be injected (or
more like oozed) between the rail and the support beam, then it seems
like this method would be a piece of cake. Also, it would compensate
for variations in the rail itself. The variabiltly of the rail would
be the width of the hole in the placards.

Any thoughts or suggestions?

--- In CAD_CAM_EDM_DRO@y..., "Doug Harrison" <prototype@c...> wrote:
> If you are developing a flat surface for mounting linear rails you
should
> consider the pad and grout method as it is less work than scraping a
> continuous surface. Scraping guru Michael Morgan explained this
one to me
> last year.
>
> In this process, shim stock is epoxied to the surface at intervals,
some
> multiple of the length of your precision level. Alternatively,
they may
> need to be placed so as to coincide with bolt locations on the
rail. These
> are scraped in using the integrating method Les described.
>
> When you are satisfied with the flatness, epoxy grout is trowelled
over the
> entire surface, the rail is coated with release agent and bolted in
place.
> In addition to being less work this provides constrained layer
damping for
> the rails.
>
> There are several variations on this method, one of which I believe
Les used
> on his gantry (Les?).
>
> Doug