[Roadsters] Windscreen, now acrylic cutting

[O'Farrell, Fergus]

Linda,
Here is what they mean by a scribing knife.
http://www.hobbylinc.com/htm/squ/squ10202.htm

Folks have used a jigsaw, but the buffeting of the material sometimes
rips the edges, so you tape it to a thin pc of plywood first.  Blade
selection for this is key to prevent the melting Phil described, clogs
up the blade teeth in no time.

So, since you are in the medical profession, would some of the neat,
sharp devices work for this?  You betcha!  You make about 6-8 strokes,
so that the groove is at least 1/3 of depth.
Remember, like cutting glass, you need to be removing a large enough
piece to grab on to, so you have to "snap off" from lets say an 8" piece
to the desired 4" piece, not from 4.25 to 4", that won't work.  Inside
radii?  Not really possible with this method.

But I must come clean.  The jr college where I sub has a composite
cutting bandsaw that would do just fine for things like this, zips them
off in no time.  Oh, and it just so happens that a former student worked
for a motorcycle fairing plastic forming biz, so there is about 650#'s
of leftover acrylic sitting around.  (I have covered all the coffee
tables in our house to keep the finish protected from my two little
"helpers" efforts)

On some of the help sites, like this:
http://www.ehow.com/how_2089221_cut-acrylic-plastic.html
Say things like this:
<< Acrylic plastic doesn't weigh as much as glass and isn't affected by
the sun or salt spray. >>

This is not true.  Lexan doesn't UV degrade (or at least is sooooo slow
it doesn't matter) but others do.  So, leave ordinary acrylic in direct
sun, every day/all day (how many roadsters still do this?), it'd start
to get foggy after 2-3 years, and if you did nothing to it it'd be
non-see-thru (technical term there) after that, depending on
region/sun/elements, etc.   (the drawback, for heat-formed parts like
Phil described, is that Lexan is a "royal pain" to form, has to be heat
soaked for like 6 hours to remove the moisture, or it clouds up on
cooldown..... BTDT....)

Group buy on a cut pattern with flame-polished edges?  I'm in for that.
I don't really have a good method (okay, don't want to spend the time
setting up the Bridgeport and setting up each piece) to cut the slots
like Brads have, but drilled holes would be no problem, and then you
could use black (or purple or pink!) zip ties.
Free materials for the group buy?  Nah, all of the leftovers are
strangely shaped scraps, which would take too much time to lay-out, and
there would be some minor flaws in them, differing thicknesses, etc.

How big a group needed?  I'll work up costs, but if it is meant to go
down between the seats to near the console/hump, we'll get a lot fewer
pieces (like 3) out of a purchased sheet (which will yield probably
5-6).

Whew, too many words.  Sorry.
Fergus O, 69 2000, HB, CA