Technical data

13773-001
51-20
Page 2 30 Nov 2000
(8) To determine the amount curing agent (CA) required for a given base resin weight (BRW) use
the following formula: CA = BRW x 0.4
For example: If a repair required 250 gm of base resin, the amount of curing agent is calculated
as follows:
CA = BRW x 0.4
CA = 250 gm x 0.4
CA = 100 gm.
Note: Mix ratio for MGS L418 resin is 100 parts resin, to 40 parts curing agent (100:40).
(9) Place a second mixing cup on the scale. Record second mixing cup weight.
(10) Add the second mixing cup weight and the curing agent weights together, to determine the gross
curing agent weight (GCAW).
(11) With the second mixing cup on the scale, pour curing agent into second mixing cup until GCAW
is obtained.
CAUTION: Material will adhere to the cup sidewalls, scrape the inside of the cup several
times to assure all material will be used. If all material is not used or properly
mixed, the resin will not obtain full strength.
(12) Mix curing agent and base resin. Stir mixture continuously and mix thoroughly. Mix resin to uni-
form appearance with no swirls or color differences. After resin appears uniform, mix for an addi-
tional two minutes. Continue to mix until no clouding is visible in the mixing cup.
B. Mixing Filler Paste
Filler Paste will be used for filling dents and gouges in core and for bonding replacement core sections.
The mix ratio of filler to resin is not as critical as mixing the resin. The filler ratio may be varied slightly
to alter the viscosity of the filler paste. Resin to filler mix ratio is approximately 1:1½ parts by volume.
Add filler to mixed resin and mix slowly until all filler is incorporated. Scrape the sides and bottom of
the container while mixing to ensure material is uniform.
Note: Filler paste must receive an initial cure per Chapter 51-20 (Cure Cycle) prior to the next
operation (i.e. laminating, sanding, etc.) (Refer to 51-20)
(1) Mix resin. (Refer to 51-20)
(2) By volume, mix the fillers 1:1 Aerosil to Sil-Cell.
(3) By volume, add filler mixture to mixed resin. Mix ratio is approximately 1:1½ resin to filler.
(4) Mix until material is uniform in texture.
C. Cure Cycle
In order to achieve full strength of a repair, the repair must cure properly. To achieve full cure of the
MGS L418/418 resin system, heat the entire repair area using an artificial heat source. Because much
of the structure consists of sandwich construction which makes it difficult to properly heat the inner
laminate, it is often necessary to perform two post-cure cycles. When it is necessary to repair sand-
wich composite, repair the inner laminate and post-cure first; then follow by repairing the core and
outer laminate.
CAUTION: MGS L418/418 resin system will not cure at room temperature to a condition suitable for
handling or processing in any manner. At room temperatures this resin system will only
reach an early stage of cure and will be very brittle and easy to irreparably damage. Do
not bend, twist, pull, or push the repair area prior to initial-cure.