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Quick $2k O-ring Question

Anton -

Yes, you do discuss a groove depth, somewhat in context with the compression of the o-ring. So, OK, we shouldn't focus on compression of the o-ring, which Oak had written about in one of his Airmail articles.

But taking your numbers from your website, and computing the compression values per the basic equation, I get the following table. Interesting, your recommendation of groove depth matches quite well Oak's recommendation of compression values of between 10 and 25%.

So while compression might not be the best way to think about this, it does appear that the two different scales really give the same range of recommendations for stack up of components.

Another question...why is there a need for a chart for the rounded edge canister and one for the square edge canister? It's all about the initial canister depth...seems to me the shape of the edge really has nothing to do with what stack up of components is needed.
 

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... your recommendation of groove depth matches quite well Oak's recommendation of compression values of between 10 and 25%.

If you actually read the page, you'll see that those are examples targeting an arbitrary 3.3mm groove depth. That's not a recommendation and I explain elsewhere why I use a larger number. The purpose of the whole page is to get you to do your own math. That's why I was more interested in knowing how the OP came up with his conclusion than I was in actually doing the work for him.

The O-ring packs fully with about 0.5~0.6mm compression. There's no need to go much tighter. This is explained on the page.

Another question...why is there a need for a chart for the rounded edge canister and one for the square edge canister? It's all about the initial canister depth...seems to me the shape of the edge really has nothing to do with what stack up of components is needed.

The sharp-edge canister cannot offer a no-shim option, so the contents of those six rows are different.
 
If you actually read the page, you'll see that those are examples targeting an arbitrary 3.3mm groove depth. That's not a recommendation and I explain elsewhere why I use a larger number. The purpose of the whole page is to get you to do your own math. That's why I was more interested in knowing how the OP came up with his conclusion than I was in actually doing the work for him.
The O-ring packs fully with about 0.5~0.6mm compression. There's no need to go much tighter. This is explained on the page.
The sharp-edge canister cannot offer a no-shim option, so the contents of those six rows are different.

Thanks for doing all the work & sharing your the info on the $2k O-ring saga.
I wasn't looking for you to do the work for me. I was wondering if my thinking was correct.
But I guess in a way that's asking someone to do a little work. :)
"The O-ring packs fully with about 0.5-0.6 mm compression" That's good to know, I must have missed that when reading your page.
Thanks Again.
 
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