whit3rd wrote:
On Sep 5, 6:17 pm, Steve Turner
wrote:
[bought bolts at Home Depot]
I get them home, and WTF? I finally realize what is wrong, and now I'm
friggin' ****ed because the bolts are worthless for my application. The
unthreaded portion of the shanks are a full 3/64" shy of their stated
diameters"!!! Oh sure, the outside diameter of the threaded portion is
3/8", but the shanks aren't even close.

Alas, that's normal. Unless you get 'shoulder bolts', the shank
diameter is not the controlled 3/8" you want, because the threads
weren't cut on a 3/8" blank, they were raised (rolled, it's called)
on a subsize blank.

I must be living in the past or something, because I just got back from
my local Ace hardware and their selection was the same; just as you
describe. This boggles my mind because I have all kinds of old carriage
bolts around here (unfortunately, none of which fit my needs for this
project) and every one that doesn't have full length threads has the
"shoulder" shank that you describe. I rarely buy them and don't
remember where I got them, but it must have been during a different era...

You can build up the shank with welding,
I suppose, or just roll a bit of sheet metal around
the shank. Or scrounge in decades-old assortments of
fasteners for an archaic example of what-you-expected.

I'm just going to invent one from a regular hex-head shoulder bolt that
I brought home from Ace hardware.

Shop with calipers.

Aye. I also need to carry a little pocket-sized tape measure with me
(like my Dad does), but knowing me I'd probably forget the dang thing.
I usually have to wander over to the tools section and "borrow" one of
their new tape measures, then put it back when I'm done. :-)

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