How drill into the end of a long piece of stock?

As part of my Z-axis upgrade, I need to attach the plate that supports the rails to the Nomad. I’m using a plate that replaces the Nomad’s stock bottom plate and screws go through the bottom into the rail plate.

It looks like this:

And the plate that I need to put holes in looks like this (the holes are on the face closest to the camera):

I need to get holes on the end of the plate, which is 7075 Aluminium.

I’ve tried using a cordless drill but it ended up slipping too much when I started (despite my best efforts to “punch” an indentation for it), and if I continued, the holes would be a little too far apart. The cordless drill is also very slow.

Does anyone have any better suggestions?

I don’t necessarily need to recover the existing holes, I can start over and just move them slightly closer together.

I just have a feeling there’s a better way to do what I need to do…

I would fashion a jig which could then be clamped in place, or purchase a dowel guide:

and clamp things up and use a hand drill to do this a bit at a time, starting with a smaller drill size and if need be using coolant. (there’s a reason boring is a synonym for tedious).

If you had a Shapeoko you could fasten the piece at the front of the machine…

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I like Will’s Shapeoko recommendation!

I have a drill press with a 90 degree table arc. Short of that, you might want to consider a jig to hold your handheld drill at a 90 degree angle to the surface…they’re relatively cheap: Here’s one of many

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Dammit, I wish I knew this existed earlier! I bought this thing for that purpose but it just doesn’t do the job. Now I know what to look for though.

I actually did this with the Nomad. It mostly worked, except the precision vice doesn’t have enough grip. The threaded table should do the job though.

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I have a similar jig, and another like to the one I linked — I use the inexpensive one for putting holes in sheet goods or boards too wide for the latter.

Call me crazy or use the phrase ‘ when all you have is a hammer everything is a nail’. But what I would be tempted to do is use the Nomad to create little blocks with the holes in them and then cut some recesses in the plate and secure the blocks to the plate

Sort of feels like a cabinet joinery type problem but in metal

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I thought about that too but I don’t think this particular joint is a good candidate:

  • Anything that goes on top of the plate takes away travel on the Z-axis.
  • Anything that goes under the plate takes away clearance height.
  • This is one of two joints that holds the entire Z-axis to the X-axis carriage, so strength and rigidity are very important.
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As Will says, some variant of the dowel drilling jig is likely your best bet.

These are quite useful

I have been using some small carbide spot drills with 90 degree tips to enlarge the punch marks before drilling, that can help.

Or you could just grab a chunk of a suitable steel, drill it vertically in a press and then heat and quench it to harden it up as a one-use drill guide.

The main thing I’d be careful of, after getting the hole on center, is making sure I didn’t let any drill wobble snap the bit off in the end of my 7075 plate…

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