depth calculated on a hypothetical sphere Ø8mm

[[El...]]

Hi,

What is the Calypso calculation for measuring the depth of 12.4mm calculated on a hypothetical sphere Ø8mm? see images.
I measured the cone at 60° and, through intersection (cone on plane 17), obtained Ø8.545.
I don't intend to insert a calibrated Ø8mm sphere to obtain the distance in question, but I would like to know
if measuring the cone can provide a relationship to obtain the desired depth.

Thanks in advance

Elvio

[[Ma...]]

If you need accuracy, then it's better to use fyzical sphere or at least R4 probe tip.

Or for questinable accuracy you can use two lines ( intersection of cone and plane to get "V" like lines ) and use "Tangential feature" - it will allow you to select circle with radius.

I am wondering if you could measure area of hypotetical touch of sphere and recall measured points into inside sphere with locked radius and tangential evaluation.
It would make a sphere sitting almost like real one - but this is not tested - just an idea

[[Ri...]]

I agree though that since 8mm spheres are very common to just use a qualified 8mm stylus that self-centers into the hole. 

 

[[Ky...]]

Hello Elvio,

 

There are a couple ways you can do this. One is a bit more complicated but probably a bit more accurate. The other is simpler, but only really takes data from one cross-section. I'll describe both and let you decide which one you like better.

 

1. You can use a result element (in size>more) and use a formula (right click in the text box). The formula will be 4.0/sinRad(getNominal("Cone1").apexAngleHalf). A graphical derivation is below. This will get you the center of the theoretical sphere, so you can then just add 4 to get a Z (or whatever axis value) from your origin, or create a theoretical sphere using that value for the Z (or whatever axis) location.

 

2. Assuming you have a CAD, you can section the cone through the middle and measure 2 2D lines on the sides. You can use a tangent construction then to create a circle with the specified diameter. You can do this without a CAD, but you would have to rely on nominals on the print to set the nominals for the lines.

[[El...]]

Thanks everyone, I'll try the various options you suggested.
Best regards

[[El...]]

Hi Kyle,
I tested strategy 1. in Calypso simulation.
I generated the cone.
With the formula you indicated, I obtained the Ø8mm. see file test.pdf
I didn't understand how to get it the distance 12.4mm?
Thanks

test.pdftest.pdftest.pdftest.pdftest.pdftest.pdf

[[Ky...]]

The value it is calculating is the distance from the apex of the cone to the center of the sphere. What I would probably do is:
 

1. Make a cone calculation feature and set it to find the position at 0 diameter.
   
2. Use that cone calculation as the X,Y, and Z origin for a secondary alignment.
   
3. Create a sphere from the "Features" dropdown menu. Set the alignment to the secondary alignment made in step 2, make the sphere theoretical and then set the diameter to the given value (8 mm) and use the formula I gave you as the Z height. Everything else should be 0.
   
4. You can then use something like a caliper distance to get the proper value.
   

Hope that helps.

[[Jü...]]

We have already inserted steel balls and touched them. This has already worked well for us on several parts.