CAD issues - missing surfaces

The

Fundamentals

Table Of Contents

Is the CAD correct?. 3

Proper part 3

Scaling. 4

Mirroring. 5

CAD issues - missing surfaces. 6

What sort of accuracy might you expect?. 8

How will you align it?. 8

Geometric PLP Alignment 9

RPS Alignment 13

Best fit on points alignment 21

Freeform alignment 24

What about the Geometric Measurement?. 28

What’s likely to be important?. 29

Is the CAD correct?

The first thing to ensure is that you have the correct CAD for the part that you are about to measure.

The main things to look for are:

· Proper part

· Scaling

· Mirroring

· CAD issues - missing surfaces

Proper part

Is the CAD is completely different to the part? If so, request the correct CAD or part.

Below you will see an example of the wrong CAD when compared to the part in the photograph.

Scaling

Scaling allows you to increase or decrease the CAD in relation to scaled parts.

The CAD above is scaled at x2 to the CAD below.

This is useful in industries where the same product is made in various sizes or prototype work where a full scale model would be to expensive, i.e. automotive or aerospace.

Mirroring

In some cases left and right hand components of the same dimensions and geometry are mirrored.

This reduces time in the creation of the CAD, as the designer only has to design one part and mirror it.

The example below shows CAD that can be mirrored.

The photograph below shows one of the two parts the mirrored CAD applies to.

CAD issues - missing surfaces

Here we have an example of good CAD with all surfaces in place.

Next we have a CAD example with missing surfaces

There could be a reason for the CAD having missing surfaces. Check that a level or levels have not been turned off.

Check if a level or levels have been turned off in CAD File Manager.

You can see now that in the User Levels, level 1 is switched off.

Click the light bulb for level 1 and the CAD view will now show level 1.

The complete CAD showing all levels associated with the CAD, whether it is a user created level or a level from the original CAD.

In this example, surfaces in the CAD had been turned off.

Дата добавления: 2015-11-16