Drilling into my Orange Vise??

Hey all! Looking for some opinions as I'm considering drilling/boring two holes into my Orange Vise (Delta IV) to add two locating down pins that will align with my fixture plate.

Obviously I'd prefer not to drill anything but so far this is the best solution I could think of that will work here.

I have an SMW fixture plate, each hole is spaced 1.25" on center. The top half of each hold is bored for 1/2 dowel pin and the bottom half is tapped for 1/2"-13 threads.

The center of the orange vise would be where the single 1/2"-13 bolt would secure it to the fixture plate but I want one or two down pins for locating/alignment as well. Unfortunately the holes are just barely off (two companies, different spacings, to be expected).
The 4 outer pin holes on the vise are designed for 96mm pull studs, the closest spacing, converted to metric, of the fixture plate calculates to 95.25mm.

My thought was I'd need to drill/bore out two extra 1/2" holes in the vise bottom to allow it to align with the fixture plate. This would allow me to mount it anywhere on the plate needed.

Unless anyone can think of a better way to do this, I'm open to suggestions

With that being said, any tips if I do have to drill/bore into the bottom of the orange vise as I'm sure it's hardened, luckily it doesn't need to be very deep, maybe 1/2" or so.
I have a second vise on the way as well, so whatever I do I'll need to do it to both vises.

note: these vises don't have any rails/edges on the sides to clamp down similar to their 6" vises so that is not an option.

It's just a tool. Modify as needed.

If the vise body is really hard, as I expect, then I would mill and not drill, and keep the holes as shallow as possible. What you want to do sounds fine to me, I'm not shy about modifying things to my needs.

thanks guys. @DavidScott would you personally mill only or would you bore out the final OD?

If you have a new vise coming it might be worth asking orange how much to add your holes. They will have it setup to bore the other holes and might be willing to add your holes for a minimal cost.

Pattnmaker said:

If you have a new vise coming it might be worth asking orange how much to add your holes. They will have it setup to bore the other holes and might be willing to add your holes for a minimal cost.

Click to expand...

Great point! worth asking for sure, thanks I'll reach out to them. I know my next vise is still awaiting production so *fingers crossed*

FirstAscent said:

thanks guys. @DavidScott would you personally mill only or would you bore out the final OD?

Click to expand...

Depends on your tolerances. I can interpolate under .0005" tir on my old mill, not sure on the new one, so that is how I would do it. For a 1/2" bore I would use 1/4" end mills, maybe a used one to rough and a newer one to finish. Spiral in with a light chip load and ramp angle with compressed air to rough. What you want to do isn't hard for a decent cnc mill.