Mirroring a part results in unnecessary lines

peter_morris

Hi,  I'm modelling a fairly simple tool-post that is symmetrical about the diagonal.  I have modelled one half and then mirrored it to create the final version, but in doing so I get a vertical lines where the two half's meet, strangely I don't see an equivalent horizontal lines.  The model is in my 'Smart & Brown Model M Mk1' folder and entitled 'Tool Post'.

Any ideas to resolve will be gratefully received.

Regareds

Peter

paul_chastell

Your sketch is unconstrained and the two faces remain two faces because they aren't parallel. See screenshot. I would suggest constraining the sketch or the mirror plane to ensure the sketch lines are exactly perpendicular to the plane.
 

john_mcclary

Oh, didn't even look at the sketch, good catch.

Even the holes are slightly off center of the mirror plane.

MBartlett21

@peter_morris
Can you please share a link?

Krz

Select "Add" not "New" in Mirroring function and select your first half part as Merge scope.

peter_morris

Hi MB - this is the URL for the model: https://cad.onshape.com/documents/afcae641e428cad745413fca/w/fd85d0d9190e07fbb3d88655/e/0edef1eefcbe8d81d146b68e
I'm not sure whether that is what you want though? Can you explain what I need to do if it isn't.

Hi Krz, sadly that is what I had done already.  If I create a New part then I have lines on both the horizontal and vertical surfaces.  When using 'Add'  its just the vertical surfaces.

I'm confused.

Thanks for helping.

Regards

Peter

john_mcclary

Not sure, may be a bug.

In the mean time, you can use "Replace face" to knit those edges

https://cad.onshape.com/documents/a834a28e27aa94463c852522/w/04f2cb23a9dd0a9579e1073b/e/680877d326df44fd0c162731

paul_chastell

Your sketch is unconstrained and the two faces remain two faces because they aren't parallel. See screenshot. I would suggest constraining the sketch or the mirror plane to ensure the sketch lines are exactly perpendicular to the plane.
 

john_mcclary

Oh, didn't even look at the sketch, good catch.

Even the holes are slightly off center of the mirror plane.

peter_morris

Thanks to you both for investigating and identifying the flaws in my drawing.  I'm returning to drawing an old lathe after a 2 year break so having to relearn OS.

The help is very much appreciated.