1/4 - 20 bolts in practice field rocket plans

When the parts list came out for the practice field pieces, I noticed there were a lot of 1 3/4 inch 1/4-20 flathead bolts with no corresponding nuts or T-nuts.

I’ve been going over the field drawings, and now I know what the bolts are for - they are driven into the front and back of the rocket so the protruding bolts on the inside serve as pegs to support the sloped chutes for the balls. Clever! But what holds them in place with no nuts or T-nuts?

If you drive the bolts into slightly undersized holes, they thread themselves (ie the bolts act like screws) and stay in place just fine. I tried with 7/32 drill bit and it works great.

But… in the field drawings, the holes are described as 0.27 inches, in other words OVER-sized. Sure enough, the bolts just rattle around in these holes.

See page 104-105 of:

Anybody figure this out? Just a goof translating plastic to wood design, or am I missing something?

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Looks like I called this one right when Frank posted the shopping list:

Those of us who used to build wooden field elements for local Kickoffs are painfully aware that drawings for those elements often have errors. This one is fortunately not hard to deal with.

"painfully aware that drawings for those elements often have errors. "

Oh my yes.

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