Garry
At first blush, the idea of drilling from one side through to the other side, is appealing
because you avoid an extra setup and save quite a bit of time, but the alignment of the holes
top to bottom will vary a bit because the bottom hole hasn't been spotted so the dill can wander
a little, one solution to this is to use a split point drill as they wander less than a jobber drill.
Although not as much of a problem, sometimes a piece of swarf from drilling the bottom
hole will jam in the flutes at the top hole. Especially in steel this can cause issues.
IF your work piece fits in the work envelope of your machine in one setup and you use a vice
stop with the material being machined square then flipping the work over for the second op
wouldn't be to bad.
As an aside, when I was a first year apprentice part of the duties was to make guide bars
long sections that had hundreds of holes in them, so this was a job that needed a reasonable
amount of accuracy but had to be done quickly, so a drill guide was made up with the hole
pattern and at each end were two alignment pins (spring dowel pins), the idea being that you clamped the guide to the work and drilled the guide pin holes and inserted the pins (removed the clamps) and then drilled the holes with a pedestal drill, this worked well as the accuracy of the work
wasn't changed by different people working on the same work piece, many apprentices over day\afternoon\night shifts.
I ran a few holes with the G83 file converter and this can be done, it really doesn't want to do this
as it has a crash test method to stop you drilling into the table.
I had to modify the code a little for this case and have made some other small changes so I'll update
the thread and plugin about it. It took eight clicks to produce the code.
I also tried just cb and mops and you can do this but with limited options, maybe this all you need
though.
Dave
