LDD Prevents valid assembly

[Nicolas]

I am having trouble with LDD not allowing me to assemble parts that I can assemble in real life. The following diagram shows to assemblies. The part with the windows fits in the hole that is vacant in the other part, without any resistance, yet LDD will not allow me to combine them. Anyone know how I can get LDD to allow this?

Edited April 25, 2011 by Nicolas

[Brickdoctor]

I think the Technic 1x1 on the left side with the 1x1 plate stuck in it might be the problem. Try deleting the Technic 1x1 and fitting the assembly into the frame.

[Superkalle]

It is because it is an illegal building technique. Read this excellent document and you will understand why.

I know a lot of people are annoyed by this "limitation" in LDD, but personally I think it's somewhat a strenght that you are forced to build according to the rules of Lego building. No cheating here

Also, note that the designers at TLG are no longer allowed to use the technique to use the Technic bricks like described in the PDF above. You may find it in older sets, but not in any new ones. However, the techinque is allowed IF there is no other bricks above.

TLG designed this brick to compensate for not being able to use the 1x1 Brick with technic hole, so use that instead on the right hand side of your design.

Final note: You can trick LDD into accepting the technique by manually editing the LXF-file and tweaking the z-axis position of the 1x1 Technic brick.

[tiammath]

Can we say "If I can do it in LDD, then it is legal" ? I mean, without editing the LXF, of course.

[Superkalle]

Can we say "If I can do it in LDD, then it is legal" ? I mean, without editing the LXF, of course.

Unfortunately not, since there are few bugs in LDD, you can actually assembly in certain ways that is not legal, for example like this: