Hapcoat™ Surface Coat Systems
Hapcoat™ 3720
White, machinable, wet plaster compatible surface coat
Hapcoat™ 3721 & 3721 LV
White, machinable, surface coat
Hapcoat™ 3726
Aluminum filled, high temperature, gel coat
Hapcoat™ 3727
Steel filled, high strength, easily applied surface coat
Hapcoat Quick Selector Chart
| Hapcoat Rigid Surface Coat | *Mix Ratio by Weight B:100A |
Gel Time @ 25˚C (GT) Tack-up time |
Cure Time | Service Temp. @ ˚F | Description |
|---|---|---|---|---|---|
3720 |
15 |
20-30 min. (GT) Tack-up Time 45-60 min. |
Overnight @ room temp. | 200 |
White machinable surface coat used with plaster and hemp to make plastic faced/plaster backed tools |
3721/7 3721 LV/7 |
12 |
35-45 min. (GT) Tack-up Time 50-70 min. |
Overnight @ room temp. |
275 |
2 Viscosities 3 Speeds Hapcoat 3721 - Thick Hapcoat 3721 LV -Medium |
3721/41 3721 LV/41*** |
12 |
25-30 min. (GT) Tack-up Time 45-60 min. |
Overnight @ room temp. | 200 |
|
3721/44 3721 LV/44*** |
12 |
15-20 min. (GT) Tack-up Time 30-45 min. |
Overnight @ room temp. | 225 |
|
3726/7 |
12 |
30 min. (GT) Tack-up Time 50-70 min. |
Overnight @ room temp. For best results, post cure 3 hrs. @ 250˚F | 300 |
High Performance High Thermal Conductivity Machinable Aluminum Surface Coat |
3726/22 |
14 |
45-60 min. (GT) Tack-up Time 60-90 min. |
24-36 hrs. @ room temp. Post cure 4-6 hrs. @ 225˚ -250˚F |
340 |
|
3726/30** |
15 |
60-90 min. (GT) Tack-up Time 2-4 hrs. |
4 hrs. @ 125˚ - 150˚F +4 hrs. @ 225˚ - 250˚F |
370 |
|
3726/41 |
12 |
25-30 min. (GT) Tack-up Time 45-60 min. |
Overnight @ room temp. | 185 |
|
3726/44 |
12 |
15-20 min. (GT) Tack-up Time 30-45 min. |
Overnight @ room temp. | 220 |
| Hapcoat Rigid Surface Coat | *Mix Ratio by Weight B:100A |
Gel Time @ 25˚C (GT) Tack-up time |
Cure Time | Service Temp. @ ˚F | Description | 3727/7 |
5 |
30 min. (GT) Tack-up Time 50-70 min. |
Overnight @ room temp. | 300 |
High Performance High Strength Steel Surface Coat Machinable
|
|---|---|---|---|---|---|
3727/22 |
6 |
45-60 min. (GT) Tack-up Time 60-90 min. |
24-36 hrs. @ room temp. Post cure 4-6 hrs. @ 225˚ -250˚F |
340 |
|
3727/30** |
6 |
60-90 min. (GT) Tack-up Time 1-2 hrs. |
4 hrs. @ 125˚ - 150˚F +4 hrs. @ 225˚ - 250˚F |
370 |
|
3727/41 |
5 |
25-30 min. (GT) Tack-up Time 45-60 min. |
Overnight @ room temp. | 200 |
|
3727/44 |
5 |
15-20 min. (GT) Tack-up Time 30-45 min. |
Overnight @ room temp. | 225 |
* Parts B to 100 Parts A by weight. The lower the ratio, the slower the cure, and the longer the working life. The higher the ratio, the faster the cure, and the shorter the working life. Starting point is the optimum ratio. See mix ratio range for other options.
** These hardeners must be cured for at least 12 hours at room temperature, and 4-6 hours at 130˚F before demolding. For models that will not take the final 195˚F temperature, demold only after the 130˚ cycle. Then bring the casting gradually up to the 195K curing level, so as not to shock the system. No distortion should occur.
*** Lower Viscosity Version