TM 5-5420-278-24&P
0076 00
0076 00-3
PAINTING INSTRUCTIONS (Contd)
SURFACE TREATMENT WITH METAL SEPARATING AGENT
a. Preparation of Mixing Components.
NOTE
To ensure proper bonding, joint flanks or bonded surfaces must be
dry, clean, free of dust and grease.
1.
Clean per aluminum cleaning specification E 02 005 0803.
CAUTION
An excess dosing of hardener (max 10:1 by volume) does not cause
a deterioration of the material properties. However, under-dosing
of the hardener will cause a deterioration of the hardener and
must be avoided in every case. A deterioration of the hardener
may cause damage to equipment. When preparing mixture with
automatic mixer, ensure correct setting of the dosing cylinders.
2.
Mix components in proportion of 10:1 by volume. Use two-component mixture within approximately
30 minutes (pot time at 75°F (23°C)).
CAUTION
To avoid metal separating agent failure, do not process GD 677
under 50°F (10°C).
NOTE
Pot time is shorter at higher temperatures. As a general rule, cut
time in approximately half for every increase of ten degrees
celsius:
30 min pot time at 68°F (20°C).
15 min pot time at 86°F (30°C).
8 min pot time at 104°F (40°C).
3.
Mix only the quantity to be processed in this time.
b. Application of Components.
1.
Coat all individual parts with separating agent on the sealing surfaces. Apply a 0.04 in (1 mm)
thick layer with a toothed plastic spatula.
2.
Assemble steel parts with prescribed torques. Separating agent must exude from all sides. Remove
excess material.
c. Hardening.
The hardening speed and the bonding structure of GD 677 essentially depend on the storage
temperature of the parts manufactured with it. At 50°F (10°C), the hardening times are doubled to
tripled, and they are shortened by about half at 86°F (30°C). A non-tacky surface is achieved after
approximately 5 hours at 75°F (23°C).
Hardening development at 75°F (23°C) on basis of the increase of Shore A Hardness:
Time (H)
2
3
4
5
6
12
24
Shore A (+/-4) 5
14
20
25
28
34
40
