DeepDiver wrote:
"Grant Erwin" wrote in message
...

I'm wondering if any of you guys know the bolt pattern of these 4 bolts.
I stuck a piece of steel under there and punched it using my transfer
punches but the pattern is really crooked


Grant, could you explain this? Why would the pattern from the actual
transfer punch marks be crooked? I mean, the holes are exactly where they
are, are they not? So how can the design specs be more accurate than what
you're physically measuring?

Yes, I can explain this. I wanted to transfer the dimensions to a 6x6x1/4" piece
of plate steel, and I wanted them centered and square. The head was not in a
position amenable to one guy working on it, to say the least. I was able to lift
up the front of it and slip the plate in behind it and set it back down trapping
the plate. Then I discovered that my 1/2" transfer punch didn't quite fit into
the holes, so I used the 31/64" punch. When I got the plate out, the holes were
all kittywampus with respect to the sides of the plate, which isn't a big deal
until you realize that on an engine stand the mount plate had better be pretty
well centered or a top-heavy item will tumble sideways before you get a chance
to clamp it. Plus, there was that worrisome error from the smaller transfer
punch, along with the worry that maybe the plate slipped during punching.

When I found the actual bolt pattern, I just milled them nice and square and
centered in my plate, came out just the way I wanted.

In hindsight, was it necessary? Probably not, but it *felt* safer. It isn't easy
for one guy to get a J-head maneuvered up in the air to bolt it to a plate, not
by half it isn't! Anything to improve the safety seemed worthwhile.

Did you see my writeup? Look at:
http://www.tinyisland.com/JheadEngineStand.html

GWE