forming silicone

[screenzzzz]

I am looking to make silicone embossing plates from a mother plate! The attached pic shows how I envision the plate to look, the mother plate is brass. The silicone that I have been looking at has the viscocity of 10 weight oil, my concerns are that there are no bubbles and that the silicone, during air curing or heat curing does not shrink and stays true to the mother plate.
I am looking for a vacuum forming system, so that can also be taken into consideration as a possible direction.
I would greatly appreciate any and all feedback.
GAry
I am also new to vacuum forming!

[greybeard]

Whatever silicone rubber you use, you're going to need a suitable vacuum degassing pot to remove all the bubbles introduced during the mixing of the catalyst into the rubber.
Don't worry about it staying true to the original - this is the main justification for using silicones. Their repro accuracy is unbeatable. So dont leave any fingerprints on your original because they will appear on the mould surface.
To get down into the bottom of your lens profile, you'll probably best using a system of vacuum pouring , as well. Pull the air out of the container in which the pattern is sitting, then open a tap to let the rubber in. That's the principle.
You can make all your own kit, it's all pretty straightforward.
John

[screenzzzz]

Hey Greybeard, thanks alot mate! I definitly give me somewhere to start and tells me I'm in the right direction.
GAry