Tabbing question...

[TANSL]

But, at least here, we avoid entraining air in tabbing, when possible.

Where does this air pocket form? A diagram, please. I'm not trying to argue with you (or contradict Gonzo), but I'd like to analyze this problem you mentioned, which I don't doubt.

 

[rxcomposite]

The figure comes from ISO 12215-6. It is probably a very scientific arrangement, extremely correct from a theoretical point of view but difficult (impossible, I would say) to put into practice. That is why I have specified that my solution is similar, not the same, as the one in the figure.

Also from LR Class rules and also from Marine Composites. It is also practiced in Aerospace composite. The stagger defines the taper and the last, longest layer has the highest surface area for adhesion.

 

[fallguy]

Where does this air pocket form? A diagram, please. I'm not trying to argue with you (or contradict Gonzo), but I'd like to analyze this problem you mentioned, which I don't doubt.

My preference is to not speak over a credentialed composites engineer, however, I will answer the question posed before he responded.

As a matter of semantics, when two tapes lay over each other, air entrains at the space under the overlap. And this is why we don’t practice it much, unless a composites engineer specified otherwise, or circumstances dictate (staggered same size tapes).

Also, if sanding, a mechanical sander will quickly remove that step the fastest, rendering the longer tape useless versus the other way where only the top edge of the short tape gets hit.

 

[rxcomposite]

As usual FG will ask a question which challenges the mind. Bubbles will and does appear during tabbing. PM me on the scientific explanation on why the outermost tabbing is always outside.