Model Forum / Radio Controlled / Air Models / April 2004

I use blank doors, with foam, or cflex, on top.

A folding table from costco..the 6 footers...

my 2 cents

Yup.  I build on 2" pink insulating foam.  You can buy a piece 8' X  2' for
very little.  I make 2 bds from this.  It is dead straight and flat.  Holds
pins perfectly and weighs nothing.  If you need a little extra holding power
for something stick finishing nails in it.  Anyway, once you frame something
up on this, stand the thing in the corner and start on the next piece.
Guaranteed it won't warp or change shape.  Best thing I've ever used for
building.
Gord Schindler
MAAC6694

Yes, but unless you want to pay for 1/4" 6061-T6 aluminum sheet and
have it cut to width and length, you'll have to build something.  Even
the 1/4" aluminum sheet will sag over time.

Any of the hobby solutions to inexpensive building boards, e.g.
celotex, building insulation foam, etc., will conform to the "non-flat
shelf" after various periods of time, some sooner than others, and I
don't think they'll serve your needs for a portable flat building
surface.

The only 'board' I know of that will stay dead flat under almost any
conditions is a torsion box.

Alas, most instantiations of torsion box building boards are large and
decidedly heavy, so setting them aside on a temporary shelf doesn't
work unless you've got a _lot_ of room and seriously sturdy shelves.

You could scale a torsion box down using thinner materials, but you'd
still wind up with something that's heavy-ish and would need adequate,
albeit perhaps not flat, support.

Most torsion boxes are built with 1/2" or 3/4" Medium Density
Fiberboard (MDF), and that stuff is heavy.  You can get 1/4" MDF if
you try, and that might lend itself to a reasonably lighter torsion
box, particularly if you limit the length and width.  A torsion box
made from 1/4" MDF, perhaps 4' long and 2' wide, would weigh in the
neighborhood of twenty pounds.

While that might seem considerable, the resulting torsion box building
surface won't ever likely warp or twist, ever.

The reason MDF is used is that it is thermally stable and doesn't seem
to care about humidity changes.  As such, it is an excellent material
for building surfaces if you add a layer of something to handle T-pins
(foam, celotex, etc.).

MDF is also the material of choice because it is assembled with common
wood working adhesives and fasteners (pneumatic nailer is _really_
handy for MDF work).  Titebond wood glue and a $40 nailer will do
nicely.  You can rent nailers if you don't have one.

See the photo album "Torsion box building table" on my web site.  Then
follow the embedded link to DIY Network to find the complete original
torsion box series of shows/articles.

A word or three of caution . . .

If you've not worked with MDF, prepare for an education in dust
control.  The MDF dust is at least as fine as balsa dust and it is
_much_ heavier.  It clumps because of static charge and it _will_
cover everything in your shop.  You also need a good grade
canister-type respirator to keep the dust out of you.  A throw-away
painters mask is worthless.  Decent canister-type respirators can be
had for about $35 or so; the Advantage 200 is a very good mask :
http://www.tools-for-woodworking.com/subcatmfgprod.asp?0=286&1=287&2=-1&6=1

You'll need access to a reasonably accurate table saw.  Building a
torsion box isn't cabinetry, but it does require ripping long strips
accurately - if the edges of the strips aren't parallel, the table
won't ever be flat.

You'll also need three or four long-reach clamps, at least as long as
your torsion box will be wide, such as :
http://www.tools-for-woodworking.com/product.asp?0=368&1=369&3=2814

I used my 10" Delta bench top table saw to cut the MDF for my torsion
box building table, and it was a real challenge keeping the heavy
stock under control.  You may be able to find a wood working shop that
will cut the MDF to plan specs.

It's do-able, and you'd wind up with an almost indestructible building
surface that is portable.
Cheers,
Fred McClellan
The House Of Balsa Dust
http://home.mindspring.com/~the-plumber

I use a cheap hollow core door (between $16-30 depending on where you get
it.) and cover it with celotex. Haven't had a problem for over 10 years with
this and both of my doors have survived multiple moves including one from
Hawaii ( hence the $30 door.). I can replace the celotex when it gets too
raggedy or dented and the door stays flat on the aforementioned COSTCO
folding tabel.

My first one cost less than $25 for the door and celotex.

Jim W