Need a super-sized micrometer

Is the thickness uniform? On a mill with a Quill DRO, I would mount a dial test indicator in the spindle and lower it to zero out on the table and zero the DRO, Then I would place the box on the table and lower the quill to zero the dial test indicator and read my thickness on the DRO. You should be able to get within a thou of the actual thickness.

The gotcha is that the bottom of the box has to be flat or at least the point of contact of the test indicator probe has to be in contact with the table so yo may have to press down in that area to establish contact.
well then if 25" then this would work best, and I would do like you did with the balls, but only one ball. mount it in a piece of AL, zero the indicator over the ball then put the box in and take measurements.

Jeff who couldn't get the O pi nion joke out.
 
That's another good solution.
Its about 13 inches to the center where the measurement needs to be taken so I did try this with a set of 18" reach calipers that I have but they seemed a little springy at the business end and it was challenging to get repeatable measurements, but I suppose with a quality set of giant calipers you could get an accurate read.
Thanks
This would actually work better. I'd be surprised if you could get the accuracy that you specified though.
 
Drill a hole in the bottom. Lay bottom on flat surface. Measure thickness with depth gauge. Patch hole with epoxy. You're welcome.

Tom
 
too destructive.
Come one, we can easily come up with a less destructive solution...
What's to destroy? He's finally admitted it was an "academic discussion" of a problem he had already solved. We've been played.

And he didn't ask for non-destructive solutions. :)

Tom
 
What's to destroy? He's finally admitted it was an "academic discussion" of a problem he had already solved. We've been played.

And he didn't ask for non-destructive solutions. :)

Tom
Wow, "played" ?

No that was not my intent Tom. I have avoided responding to your post but I feel like I should now because your destructive measuring method is completely valid and you are correct in that I did not specify in the beginning that holes were not allowed. When the discussion began I did not specify that there was a problem to solve. Go back and read the 1st line of the post. I only asked: "What would be a few acceptable methods to measure (nearest .005) the thickness of the bottom of the box (in the middle) on the attached drawing ?"

I was not trying to "play" anyone. Never have. If you go back and read the thread from the start, you might change your mind but probably not. I’m almost 60 years old and one thing I’ve learned is there are different ways and different solutions to lots of questions in life. Machining in particular is a craft where most folks tend to be very creative with solutions and processes, and since I found this website I have found it very helpful and, for the most part, a great source of valuable information. The description of this sub forum states "Metrology is the science of measurement. This forum is for discussions of using measuring tools, measuring projects, setting up work and machines. From the description I thought it would be nice for other members to see some varying solutions to a measuring problem, (although rare) that would be possible with different types of equipment they might, or might not have in their shops. Some folks don’t have all the answers and some don’t know what questions to ask. I find that to be some of the greatest value in a website like this. It probably doesn’t happen to you, but some people on here read some post, unrelated to their project, but find some eureka moment regarding a process or a method that they had not thought of, and are able to apply that to other projects they may have.... You know that … “dang, why didn’t I think of that?” moment.

You can always unfollow the discussion and if the moderators feel like there’s too much controversy, then I guess they can delete it. I hope you change your mind. Again, Thank you for the solution you contributed to the discussion and please accept my apology if you felt you were being played.

Take care
 
Last edited:
Back
Top