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Problem about assembly


New member
Hi everyone , i am new catia user. As you see i want to draw this (its V type cement trailer ) Normally i am using solidwroks. I draw this part by part beacuse
we have plasma cut and i place on sheet metal. I drew all of parts on catia but cant assembly, i dont get it why it happening.

solidwroks 111.jpg

catia 123.jpg


Super Moderator
You have to add assembly Constraints to position all the parts together. (just like adding Mates in SolidWorks)

First, right-click on one of the parts and choose Fix to lock it's position.

Then use the different types of Constraints (Coincidence, Contact, etc) from the menu on the right side to mate the other parts relative to the fixed part. You might want to use the online Help to learn about them.
Last edited:


New member
i fixed first part


cant use contact constraint. i want to contact them mauth to mauth ( sorry for my bad english ^^)


Super Moderator
lots of options here:

Instead of Contact constraint, you can use a Coincidence constraint. Or, an Offset constraint with distance = 0.

If the mouth surfaces are not planar, you might be able to use the axis planes to constrain to.