DaveK wrote:

Here's a trick that I've used with some success, put the bolt in the drill
chuck ! But first you need to get a drill bit clamped very close to
perpendicular. I put the bit upside down in the drill chuck, leaving the
shank exposed. Then I raise the table up so that I can tighten a vise on
the bit (using a spacer as needed). With the drill secure in the vise,
loosen the drill chuck and lower the table with the drill bit. THEN put the
bolt in the drill chuck.

But Dave, the OP said:

i have a small craftsman drill press, plenty of drill sizes,
and a starret auto punch.

It's rather unlikely that his "small" drill press has a 3/4" chuck, and
that's what's needed to span the head of a standard 1/2" hex bolt.

snipped


I'd not wager much that one can get the hole within 20 thou of center every
time, but it should be pretty parallel, and it's a method you can try with
your drill press.

You're a better and braver man than me Dave. The heads of garden variety
bolts aren't exactly precision machined features. Whenever I've tried to
chuck a hex bolt by its head in a 3-jaw the wobble at the business end
of the bolt was humungous!

SWMBO just asked me to take the kitchen garbage out, so on my way back I
ducked into my basement shop and stuck a couple of brand new 1/2-13 x
1-1/2" bolts in the 3-jaw on my little Stark lathe to check my memories.
TIR at the ends of those bolts was about .08" for one and over .11" on
the other. (I know that my chuck ain't great, but it's not *that* bad.)

But, "pretty is as pretty does" so if it's worked for you Dave then G-d
bless 'ya and I'm not gonna sit here and tell you that it won't. G

Cheers,

Jeff

--
My name is Jeff Wisnia and I approved this message....

(W1BSV + Brass Rat '57 EE)

"As long as there are final exams, there will be prayer in public
schools"