Making strong rubber/silicone diaphragms

[Goofy]

Yes, I also use them to make gaskets for all kind of machines.
I cut them out on my 80 watt lasercutter, but it smell´s like h*ll . . .

BR

[Tom Booth]

I had sent for some silicone baking sheet liners a while back, that just arrived recently.

I don't know if they are the best thing yet, in terms of actual durability in use, or suitability for the application, but they seem very slightly thinner, possibly than the microwave liners, but I think equally elastic and tough. The advantage might be the size, if there is a need for some kind of diaphragm that big.

These seemed reasonably priced to me, and are available from various online vendors.

The name threw me "activated" but that is apparently just a name. They are pure silicone, I think.

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[Trevor]

I use these ones Tom and are very strong.
I buy them from the cheap shops for around $5.00 AUS and are cooking bowls and can with stand 300+ Deg C. I have used them for water pumps in my Engines and have lasted a few years without wear. Hope this helps

[Trevor]

Hi Tom Again
Forgot to tell you I use these for casting my silver items as well. Temperatures used here are at 500 Deg C and have not caused a problem.
So temperature here is no problem for our hot air engines. These cake tins are around 8" diam (200mm)
Trev

[Tom Booth]

Thanks, looks like silicone. I haven't seen those locally here in the US, New York Is there an online source?

I found these square cake pans:

Silicone Deep Dish Container Tray Cake Pan Aprox 8"x8" + Carving Scrape Tool, Baking Bakeware Brownie https://www.amazon.com/dp/B00O2SJSVS/re ... UTF8&psc=1

Silicone baking material in general seems like a good option. I'm going to try it in my so-called "Hit-N-Miss" experimental engine.

I think I've figured out a way to do what I have in mind using LTD engine parts I have on hand.

That is, I'm taking out the displacer and replacing it with a diaphragm/air spring.

To raise the bar a little. Is there any flexible, rubber-like material that could withstand, say, 1000°F ? 2000 ? Higher ?

[Goofy]

Hi

I really like this one !
Just perfect for oscillating movements ;-)

Remember to tell your wife it´s for science R&D, when you buy a bag of them . . .

https://youtu.be/PrPCPwAGkps

Anyway it´s a useful idea.

[bellaedward]

I’ve been working on making my own silicone diaphragms too, and I know the struggle! Spreading silicone caulk on glass can be tricky, but using paper and spacers has definitely helped me get the right thickness. Wax paper might make it easier to peel off compared to regular paper. Another option to consider is silicone molding sheets for a smoother, more consistent finish.

For materials, I recently got my silicone sheet here [https://www.dealsandstealstoday.com/view-your-deal/] and it’s been amazing super affordable and durable!