That thread seems to be press fitting into sheet metal. What about directly into aluminum tube? And how many thousandths of an inch would you recommend? Also, to cut into the tube, can that be done? The you hinted at is more for sheet metal, which we do not have access to.
Sheet metal and the wall of your tubing has little difference when you are press fitting a bearing into it. you should be able to use the same sizes as that thread states.
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