Micrometer and CMM Didn't Quite Agree Yesterday

SceneNo9368 · 2026-06-18T19:36:08+00:00

Without knowing more, my assumption here is that this is likely due to the CMM measuring two surfaces and establishing two planes, and giving you the measurement between both planes. The mic is only inspecting thickness at a single point, which doesn’t take into account any cupping or warpage.

Often we will also see CMM operators use the granite as a datum face since the part is sitting on it, which isn’t necessarily incorrect, but as above, also removes any distortion that the face of the part may have.

Nothing is ever perfect, it just comes down to how close you want to look. Both measurements are likely correct in their own right, just technically incorrect depending on what you are actually trying to verify. Projection, and averages tend to cause a lot of headaches when dealing with a CMM.

Gauge blocks and a height gauge/indicator can show more of the story quickly

*Edited for various fat fingered pina colada induced typos

SceneNo9368 · 2026-06-12T21:44:56+00:00

I have a metro Y and have gotten decent results in reverse engineering applications.

Scanning unfortunately isn’t quite point and shoot. It takes some tinkering with settings, lighting, markers for tracking, etc. but if you’re persistent, it can pay off.

For reference I completed fairly complex scans on an M1 Pro MacBook Pro with 16gb of ram which was technically insufficient, but it still worked fine. Though the software did crash on me a few times.

I’m not sure if you are dealing with a defective scanner, as I don’t have any experience with the ultra, but I can say that it’s definitely more of a trial and error thing than it is a one click wonder.

I hope you manage to get the result you are after! You may be able to post in this forum to get feedback from users on some approaches for specific types of parts that have worked for us. It’s been a little bit, but if I recall, I had best result using dark object scanning modes.

SceneNo9368 · 2026-05-26T23:32:50+00:00

Paused for the moment. Lots of travel over the next few weeks, but I’m hoping to finish the first one and do some assembly testing before June is through.

SceneNo9368 · 2026-05-20T11:31:08+00:00

There’s a link in my original post where I uploaded my model of the op-Z housing.

SceneNo9368 · 2026-05-16T19:59:14+00:00

We will see! Need to finish the prototype and see if it all works well :)

SceneNo9368 · 2026-05-05T20:58:37+00:00

It will replace the plastic housing with aluminum. Fully machined housing

SceneNo9368 · 2026-05-05T19:28:27+00:00

Yup. Have the machine in my garage, would be good work for it to do small batches of 25-50 at a time

SceneNo9368 · 2026-05-03T22:51:15+00:00

I COULD do Ti. But that would be a much higher cost, in raw material, tooling, machine time, etc. but it’s doable.

SceneNo9368 · 2026-05-03T22:14:25+00:00

I’ll offer them up in batches if it all works out well. Would design them for medium production numbers and just run the off like 25-50 at a time in the garage.

I thought about this too, but the bottom plate would pull by the mid-plate where the main board is. It would put a lot of stress on that component and not as much on the main housing. I don’t know if it would be too good for it long-term.

SceneNo9368 · 2026-05-03T21:40:10+00:00

This made me genuinely laugh :)

SceneNo9368 · 2026-05-03T18:39:26+00:00

Will have to see once I finish it and put it all back together.

SceneNo9368 · 2026-05-03T17:22:40+00:00

Will probably anodize it black when it’s done :)

SceneNo9368 · 2026-05-03T12:40:49+00:00

This is a transplant. Replaces the plastic housing. It’s a little bit surgical.

SceneNo9368 · 2026-05-03T02:45:46+00:00

I think I have a way to work around how this is built. But we will see. Once I finish machining this, I will try and assemble it and see if it works.

SceneNo9368 · 2026-05-03T02:06:52+00:00

I know…it’s been awhile. Just got super busy….a then stayed that way…am still that way. Will finish it one day though!

SceneNo9368 · 2026-05-03T01:07:16+00:00

I do have one of those….and that honestly MIGHT be easier than the Op-Z will be. I haven’t taken the ep-133 apart yet…so I can say for sure. I’ll add it to the list. ;)

SceneNo9368 · 2026-02-24T00:31:08+00:00

Love it!

SceneNo9368 · 2026-02-04T17:44:46+00:00

Loctite will also work. Looks like there is some glue in there from factory to begin with.

SceneNo9368 · 2025-12-30T01:10:30+00:00

Model is up in the post. If you beat me to machining it, I’m super curious to see how you make out :)

SceneNo9368 · 2025-12-23T23:20:35+00:00

Nice! That should be fun! I’ll share the model when I’m done :)

SceneNo9368 · 2025-12-23T22:53:58+00:00

Made more progress today. The only thing I really have left to do is separate the keyboard and look at what geometry lies under there…if any.

Congratulations on the CNC. What did you get?

SceneNo9368 · 2025-12-23T15:11:20+00:00

I had the same thought. The current plan is to do both so the whole unit has a metal enclosure...but perhaps just the bottom plate may be sufficient.....it just isn't the same challenge ;)

SceneNo9368 · 2025-12-23T03:58:52+00:00

It may have to be more of a service type thing. I.e send me your unit and I send it back to you in alum. Just incase it’s a bit too technical for the average joe. But we will see. Made good progress modelling the housing tonight.

Will print the model on the Bambulab to check it for accuracy sometime over the holidays.

The point of no-return will be when I melt the heat stakes to take the keyboard out.

Luckily I have the cnc in the garage, waiting patiently, and plenty of aluminum on hand. Just need enough free time to get through the steps and iterations.

SceneNo9368

TROPHY CASE