Re: Foam-core Toroids

["Jim Lux" <jimlux-at-jpl.nasa.gov> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

> 
> Original poster: "Antonio Carlos M. de Queiroz" <acmq-at-compuland-dot-com.br> 
> 
> > I'm interested only in sizes larger than my 6" x 22" so life preserver
cores
> > don't help.  Any thoughts on whether such a styrofoam core could be
> > custom-made for a nominal fee?
> 
> I imagine that it would be rather easy to make one, by cutting 
> calculated rings from styrofoam boards (with a saw blade, by hand), 
> stacking and gluing them, and then finishing the surface with sandpaper.
> The result would not be uglier than a toroid made with aluminum duct.
> But it would be tricky to produce a smooth surface with aluminum tape,
> since you can't press it effectively against that soft material.
> 

Excellent idea Antonio... Cut the rings out of 1" or 1/2" boards with a
"hot knife" or a hot wire.  Surely everyone has a variac to run the wire? 
Stack' em with glue (watch out what kind of glue you use.. most solvent
based glues will rapidly dissolve the foam... try regular old white
glue..), sand the profile smooth..

Then, to solve the soft surface problem, use bondo or spackle. A THIN
LAYER, or it will weigh a ton (the stuff adds up quickly). Sand, tape,
burnish to that mirror bright finish you want.