Tech question; I think I'm overthinking what I'm thinking
This is the setup for the rear motor mounts on my DB-1, through the frame into the bellhousing / oil tank. I seem to recall that the placement of the first thread on a bolt that receives shear forces is critical to prevent stress fractures. I think the first thread is located in the "cup" thickness, which may be okay, or alternatively, may get some shear force from both sides [the spacer is snug but not tight in the cup]. If I add a washer, I loose X - number of threads into the insert, and may end up with the thread at the juncture of the spacer and the outer cup. If I don't add a washer, I may have an additional problem. When I tighten the bolt hand-tight, there is 0.06" between the insert and the spacer. Add in the thickness of the cup [0.1"], and you get 0.1" minus 0.06 = 0.04" thread length to take the tension of torquing the bolt before the last thread hits the insert, I kind of think torqueing a bolt stretches the bolt in thousandths, not hundredths of an inch, but that is a "pulled out of the air" guess.
So the questions are; Where should the last thread be in this setup? and
Do I have enough room to torque the bolt without running out of thread? [Actually, the question should be, will the clamping force of a 45 ft/lb torque, compress the bolt head / spacer / frame cup more than 0.04" and how will I know if I am wrong, before I damage the insert?]
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