[difalkner]

Why do you even need the tramming plate? If the spindle mounts had flanges either side, they could be mounted directly to the z stage plate. Tramming could be done by having slightly oversize bolt holes on one side. Might be less convenient and more time consuming, but once done, way more rigid, Also, if you're concerned with weight, the individual spindle mounts could be half the thickness of the original single mount. Or you could bore some holes or pockets to lighten things up.

Unfortunately the mounts do not have external flanges and that would be so much easier. To tram with the original plate and mount style I have requires me to test for perpendicular, shut down, remove the spindle, make a tiny adjustment, and test again hoping I get it right quickly 'cause that's going to get really old really quickly.

However, here's a new development, guys -

In keeping the tramming plate I get the ease of tramming, but assuming no catastrophic event, once it's set I shouldn't have to do it again. However, and I didn't notice this when I changed out the plates, today I realized the original plate is 0.200" thicker than the tramming plates. They are 0.600" where the original is 0.800" and that's a significant difference.

The extra mount should be here in a couple of days and I can see how large the mounting holes are, to see if there's any wiggle room for tramming without the tramming plate. I guess another advantage to using the original plate is that it's already off and will be easy to drill and tap.

Original plate with proposed new mount location (approx.) -
Attachment 438202

Original plate thickness relative to the new plates -
Attachment 438204

Close up of the original plate thickness relative to the new plates -
Attachment 438206

Thoughts now, given what I just learned?

David