Can an "offset" value be a user parameter?

[lemelman]

I've created a special gear wheel consisting of a standard spur gear, with a central recess created by subtracting another spur gear. After 3D printing, the recess was very slightly too small so I created a user parameter called "offset" with a value of "1mm" and then used the offset command on the recess with a value of -offset, and extruded the result to make the recess bigger by 1mm all round. That seemed to work OK (I used 1mm just to make it obvious). I then changed the parameter value to a more realistic 0.1mm, but the recess was unchanged; the offset cut remained at 1mm.

I've tried various values for the parameter, even set it to 2mm, but the actual recess remains unchanged.

Should the offset command obey the user parameter setting, or have I done something wrong?

[TrippyLighting]

Yes, I should. Just tried it out.

Can you share your design ?

[lemelman]

Here's the file. I tried setting the "offset" parameter to 4mm just so that it would be obvious, it didn't update the model.

I really want to try 0.1mm and 0.2mm.

[jeff_strater]

Hi @lemelman,

I looked at your model, and, unless I missed something, the "offset" parameter is not used anywhere else in the model.  You can tell this because you can delete this parameter and there is no warning.  In order for you to connect that parameter to an offset (I assume you mean a sketch offset), you have to edit the dimension in that sketch offset and type in "offset" as the value for that linking to occur.

Jeff

[lichtzeichenanlage]

@jeff_strater: Couldn't find it either but big thx for the shortcut 😉

[lemelman]

Hi Jeff (and anybody else who might be interested),

You are right in one respect; the "offset" user parameter is used only once in the model. But it was used as you specified.

I actually want to 3D print a few variations of the model with slightly different sizes of gear shaped recesses. My idea was to set the offset value to 0.1, print the model, change the offset to 0.2, print the model, etc.

I've attached a Screencast of what I did. After changing the value of the offset parameter I expected the model to update, but it didn't.

I've successfully used parameters on other dimensions before , so what an I doing wrong with this one?

[jeff_strater · Accepted solution]

Ah, yes.  Thanks for the screencast.  Yes, this is a known bug - the Offset command does not capture the parameter reference.  This one is being worked on now.  In the meantime, you will need to go into the parameters dialog and re-enter the "offset" parameter into the equation:

Jeff