Form Panel Thickness
Strength and stiffness are greatest when applied with face
grain across supports. Table 1 shows the required panel
thickness when applied in this manner. The required panel
thickness may be determined from Table 2 when panels are
applied with face grain parallel to supports. Refer to APA
-Engineered Wood Association "Plywood for Concrete Forming"
and to American Concrete Institute "Formwork for Concrete" for
detailed design information.
Edge Support
Unless panel edges are supported,
edges may have greater deflection than the center of the panel
and may exceed calculated deflection under conditions of high
moisture or sustained load.
Care and Handling
1. Preparing
B-Matte 333 MDO for Use B-Matte 333 MDO panels are
factory treated with a chemically active release agent prior
to shipment. However, Olympic Panel cannot control the length of
time between manufacture and actual use. Because the release
agent's effectiveness can dissipate over time, a light
application of release agent should be made prior to first
use. This should be a chemically reactive release agent
compatible with the factory treatment. After forms have been
stripped and cleaned (before each successive use), the panels
should be re-coated with a chemically reactive release agent
using ½ to ¾ gallon of agent per thousand square feet of panel
surface.
2. Pouring and Vibrating
B-Matte 333 MDO resists
abrasion and impact. As with any surface, however, B-Matte 333
MDO can be damaged through improper use. Rate of pour should
be limited to that assumed in the design of the form. The use
of rubber-tipped vibrators is recommended. Care should be
taken not to damage form faces during vibrating.
3. Stripping
Most form panel damage occurs during
stripping. B-Matte 333 MDO's life can be prolonged with proper
stripping and handling. Use wood wedges rather than metal bars
or pries to separate the form from the concrete.
4. Cleaning, Storage, and Edge Sealing
Clean
panels after each use with burlap or flat, non-scratching
tools such as plastic or wood scrapers. The overlay and wood
substrate could be pulled from the panel on subsequent pours
if concrete sticks to the surface. B-Matte 333 MDO is factory
edge sealed. However, it is important that any cut edges or
exposed wood at holes or openings be resealed with two coats
of an appropriate sealant to retard moisture penetration and
possible panel swelling. Stack panels flat to prevent warping.
Store panels in a protected area and avoid direct sunlight to
minimize degradation.
5. Surface Repairs
It may be desirable to fill in
nicks and gouges to restore surface continuity when B-Matte
333's surface becomes mechanically damaged. Clean any concrete
or release agent from the damaged area and, using a putty
knife, apply a polyester resin auto body putty (such as, but
not limited to, Bondo Auto Putty by Dynatron Bondo Company,
Atlanta, GA 30310). This and similar products are available at
auto parts stores throughout North America.
