Operation manual for vacuuming process
Vacuum mold: remove the residual air after mixing the silicone and curing agent to avoid bubbles after the silicone is cured.
Operation process of vacuuming liquid silica gel:
1. Process the model first, and prepare the ratio of silicone and curing agent. Normally, the ratio of silicone and curing agent at 25 degrees Celsius is 100:2. If you use an electronic scale to weigh 100 grams of silicone and add 2 grams of curing agent, use a stir bar Or a blender can mix evenly, some of the glue is first brushed on the model and half of the silica gel is put into the vacuum chamber to vacuum. If the model is too large to be put into the vacuum machine, only the silica gel is vacuumed according to the actual amount . Determine the size of the container containing the silica gel according to the amount of silica gel. The amount of silica gel should preferably not exceed half of the container, otherwise it is difficult to clean and easy to overflow.
2. Put the silica gel in the vacuum box, put some waste paper or plastic bags in the vacuum box under the silica gel to prevent the silica gel from overflowing in the vacuum box and difficult to clean up when vacuuming.
Close the vacuum box buckle, open the exhaust valve, close the exhaust valve tightly, turn on the power again, test whether the exhaust valve is closed tightly, put your hand next to the exhaust valve. If there is airflow, it means it is not closed tightly. bubble.
3. After starting to pump the vacuum, check the vacuuming of the silicone inside through the viewing glass. If it is about to overflow, you should immediately open the vent valve, and then close the vent valve when the silicone sinks. Repeat the operation.
When there is no overflow of the silica gel and when the silica gel sinks slowly and there are no bubbles on the surface, the vacuum gauge is -0.1Mpa at this time, and the exhaust valve and power supply can be closed. At the same time, open the vent valve not to be too large. Let it be first Slowly deflate. When it reaches 0.4Mpa, the valve port will be enlarged and quickly deflated. When the vacuum gauge is 0Mp, the vacuum box can be opened and the silica gel can be used. It is better not to exceed 10 minutes for the entire vacuuming process to prevent the silicone glue joint from being used.