Do you make any large complicated molds before,may be you think that must make with platinum HTV silicone Rubber or platinum liquid silicone, but today i want to tell you RTV2 silicone rubber also can make that, Do you believe or not ? Here we go.
Today i want to share silicone technology about " Precautions for making large molds" Do you have interest ?
You may are a professional silicone user, but some of your workers or buyers are not. Recently, we visited some clients, we have faced these questions, some bigger silicone mold performance is not good. and the tear strength is not good.
The reason is operating way. Not the quality of the silicone. Here are some pictures for your reference
1. For this bigger mold with complicated pattern, the suitable hardness is very important. 20-25-30 shore A is the best.
2. Platinum silicone rubber is more suitable than tin cured silicone. (also, the cost is a little higher) It will be cured under room temperature and can be cured fast by heating, It’s two-components liquid silicone rubber ,It has an exceptional fluidity and good operate. Especially, the platinum cured silicone rubber has a lower shrinkage, higher temperature resistance and it is flexible.
3. Operating way
1) Decrease the mix ratio of the catalyst. If you plan to use the 100:4, for the first brush time, you just add 2-3% catalyst to prolong the cured time. The purpose is decrease the bubbles. Only with the little bubbles, the density is lower, the tear strength can be well. Also, more catalyst added will affect the quality of silicone. For the second time and third time brush, you can add more catalyst like 4% catalyst to mix.
2）Use the silicone release to the surface mold before brush the silicone
3) Use the fiberglass after finish the first time brush.
All the silicone almost the same, high temperature with a long storage, the faster thickening will be, this is a normal reaction of silicone. Please noted.
I hope that some of the suggestion here will be useful to you. If you have any suggestions(service, price, quality) for us, we can share each other together. And free sample is available for your test. By the way, if you need price or samples, Please contact us freely.