Re: ATM Some help with "Alice" type design

["Bob Scholtz" <rscholtz01@sprynet.com>]

Johnny, my brother-in-law is the designer and owner of the Alice scopes, so
I'm pretty familiar with the designs.  I'm not sure I understand your
question.  The channels are designed to align the truss tubes and are
individual pieces that are attached to the mirror box.  The channels can be
routed or fabricated from 3 pieces of wood and then the channel(s) is
attached to the mirror box; top and bottom.  The alignment issue is how
precise you line up the channels relative to the mirror box; if the channels
are the correct width you should be able to push them into the corners and
the alignment is essentially automatic if the mirror box is square.  Should
you miss by a small amount, you can compensate in the design of your focuser
board.  If this doesn't help rephrase the question and I'll try again.

Bob


----- Original Message -----
From: "Johnny" <takmais@swbell.net>
To: <atm@shore.net>
Sent: Sunday, July 22, 2001 1:18 PM
Subject: ATM Some help with "Alice" type design


>
> I could use some help with certain aspects of the "alice" 2 tube truss
> design dob.  I'm starting to get frustrated for fear that i may not be
able
> to complete this certain step.  if anyone is very familiar with the design
> i'd appreciate their input.  i'll go ahead and ask the questions here and
> anyone who knows can give it a shot.  thanks
>
> 1.  how precise must the top and the bottom truss channel blocks be
> constructed?  I've read 2 different designs, one saying to use 1.75" wide
> wood, and the original aritcle saying 2" wide blocks.  I'm using 1/2"
> plywood for the scope and ive drawn out this design in cad both 2d and 3d
> modeled and i cannot get the 2" wide blocks to work in the design.  I
cannot
> get the center of the truss at the top channel to line up with the center
of
> the truss at the bottom channel using 2" wide blocks.  I CAN do this with
> the 1.75" wide ones though.  My idea on how i might create these easier is
> to buy an 8' long piece of 1/4"x1 5/8" lattice strip.  The strips actual
> width is just a hair under 1 3/4", maybe a 16th or 32nd short.  I'd only
> need like 22" of it so i'd cut it in half and then take the other half and
> make 2 strips which i could glue to the other one that would make a 1"
wide
> gap between the 2 glued strips.  this would give me essentially the same
> configuration as the design calls for without me having to use a router
for
> the 1" channel or make cuts that might be unsquare.  follow me so far?
The
> problem appears to be that of the relationship between the width of the
> blocks and the thickness of them.  if the width is too great or too
little,
> itll throw off the truss positions.  i'm worried i wont be able to get
close
> enough here.
>
>
>