Jeff,
Got your message on the adhesive we used between the ethafoam and 7/16" OSB
board for on the mat support flooring...
I tried about 20 different adhesives as did Paul Nogaki from S.Cal see..
http://judoinfo.com/tatami.htm
Denver Dojo Floor:
http://www.judocalendar.com/denverdojo/Floorsystem.htm
I've also talked to Paul about this since then and he agrees on much of the
following...
The connection of the foam blocks to the sheeting is really just so you can
turn them over after locating the foam blocks into the proper pattern. You
don't want to loose the pattern when turning and moving the sheeting
around...
It seems like nothing sticks well to the ethafoam. ( except what ever they use
in the factory seems great, but I don't know what that is, couldn't find
out... Maybe press Tim to get material and source for us... and if you do
find out let us know???)
Otherwise the best adhesive that I've found is contact cement.
The same thing they use for Formica laminate for counter tops... It's also
the cheapest one I tried!
I purchased it at Home Depot for something like $15 a gallon??? Used throw
away 4 inch wide brushes and coated both surfaces ( ie the foam and sheeting
) in the area of contact, let it dry completely then press together. ( this
worked best of all the very expensive adhesives we tried) And you can be
sloppy!
( We used a butcher paper template for the pattern, it's the same on all
sheets, just rotate adjacent rows of sheeting 180 degrees so the rows line up
on the diagonals across sheets...)
The other thing Paul and I discussed that I would do differently next time...
Paul screwed the two layers of sheeting together with like 20 to 30 fasteners
per 4x8 sheet. I did not and just let them float. I had to add strapping
under the tatami on top of the sheeting later to try to keep the tatami from
separating and having gaps in between (toe traps).
We both used velcro on the perimeter mats, but Paul's worked because his
sheeting did not separate after a few weeks of judo play...
I ended up retaining the perimeter mats with 2x4 with the 2" poly strapping
stretched under the tatami from edge to edge of the mats and wraped around the
2x4's before I figured out that I should have just fastened the sheeting
layers together and relied on the velcro...
Other thing Paul and I agree on is to use the 7/16 OSB... Paul used full 1/2
plywood and he thinks his floor is quite a bit stiffer than ours (part of that
may be that the two sheeting layers are fastened together adding stiffness
?)
He (and I both) like our (Denver Dojo) floor's stiffness very much... I have
not been to Paul's dojo to try hhis, hope to get down there sometime... S.Cal.
Hope this helps!
Jim
574 340 3850 cell
303 623 3362 home/dojo
719 Mariposa St
Denver CO 80204
www.denverdojo.com
James Carmer
719 Mariposa St
Denver, CO 80204
303 623-3362 Ph
574 340-3850 Cell