I need to make a flat tabletop worksurface 40" x 96". It will only be
supported 3 spots over the 96" length at 6", 48" and 90" from either
end. I want to come back and measure it years from now and its still
flat. The other criteria is I only have 4" of clearance below the top.
Flatness should be what is praticle with an 8' straight edge and feeler
gauges. Ideally a maple top that I could put an mdf wear surface on
would be great except, I haven't had any luck finding one that size, and
the cost of one smaller plus shipping is pretty hefty, $400+. It won't
be supporting lots of weight, just the usual woodworking worktop.
Ideas?
Phil
I am using my Dad's workbench. It is a 36" x 72" solid wood door, 1 1/2"
thick from Weyerhauser. This door is 60 years old and still dead flat
across the entire surface. It is supported by a 3x3 post on each corner -
no support in the middle. This thing is so heavy my brother and I can
barely carry it.
Bob
"Phil" <[email protected]> wrote in message
news:[email protected]...
> I need to make a flat tabletop worksurface 40" x 96". It will only be
> supported 3 spots over the 96" length at 6", 48" and 90" from either
> end. I want to come back and measure it years from now and its still
> flat. The other criteria is I only have 4" of clearance below the top.
> Flatness should be what is praticle with an 8' straight edge and feeler
> gauges. Ideally a maple top that I could put an mdf wear surface on
> would be great except, I haven't had any luck finding one that size, and
> the cost of one smaller plus shipping is pretty hefty, $400+. It won't
> be supporting lots of weight, just the usual woodworking worktop.
> Ideas?
>
> Phil
>
I would be quite satisfied with .01.
patrick conroy wrote:
> "Phil" <[email protected]> wrote in message
> news:[email protected]...
> >
> >
>
> > Flatness should be what is praticle with an 8' straight edge and feeler
> > gauges.
>
> Which ones? 0.001?? 0.01? How flat?
>
> > Ideas?
>
> DJM built an assembly table flat "enough" for woodworking purposes using a
> torsion box approach with MDF skin.
I had considered building a torsion box, the problem to me is getting 90" of
straight surface for the supporting members. 4' or less no sweat...
Pat Barber wrote:
> Torsion Box:
>
> (2) sheets of 1/4" plywood
> (1) sheets of 3/4" birch plywood
> (2) sheets of 1/2" mdf
> glue
> Staples and gun.
>
> Make the frame out of strips of 3/4" birch ripped to 3",
> with interior seperator strips "about" 6"-8" apart.
>
> Skin it over on both sides with 1/4" ply using glue and
> staples.
> Top it off with 1/2" mdf.
>
> Very flat and very strong.
>
> How flat depends on you.
>
> Phil wrote:
> > I need to make a flat tabletop worksurface 40" x 96". It will only be
> > supported 3 spots over the 96" length at 6", 48" and 90" from either
> > end. I want to come back and measure it years from now and its still
> > flat.
"Phil" <[email protected]> wrote in message
news:[email protected]...
>
>
> Flatness should be what is praticle with an 8' straight edge and feeler
> gauges.
Which ones? 0.001?? 0.01? How flat?
> Ideas?
DJM built an assembly table flat "enough" for woodworking purposes using a
torsion box approach with MDF skin.
"Phil" <[email protected]> wrote in message
news:[email protected]...
> I need to make a flat tabletop worksurface 40" x 96". It will only be
> supported 3 spots over the 96" length at 6", 48" and 90" from either
> end. I want to come back and measure it years from now and its still
> flat. The other criteria is I only have 4" of clearance below the top.
> Flatness should be what is praticle with an 8' straight edge and feeler
> gauges. Ideally a maple top that I could put an mdf wear surface on
> would be great except, I haven't had any luck finding one that size, and
> the cost of one smaller plus shipping is pretty hefty, $400+. It won't
> be supporting lots of weight, just the usual woodworking worktop.
> Ideas?
>
> Phil
torsion box
"Phil" <[email protected]> wrote in message
news:[email protected]...
>
>
> I would be quite satisfied with .01.
How about this:
http://www.diynet.com/diy/shows_wwk/episode/0,2046,DIY_14350_26946,00.html
Torsion Box:
(2) sheets of 1/4" plywood
(1) sheets of 3/4" birch plywood
(2) sheets of 1/2" mdf
glue
Staples and gun.
Make the frame out of strips of 3/4" birch ripped to 3",
with interior seperator strips "about" 6"-8" apart.
Skin it over on both sides with 1/4" ply using glue and
staples.
Top it off with 1/2" mdf.
Very flat and very strong.
How flat depends on you.
Phil wrote:
> I need to make a flat tabletop worksurface 40" x 96". It will only be
> supported 3 spots over the 96" length at 6", 48" and 90" from either
> end. I want to come back and measure it years from now and its still
> flat.