I have a model of a small cabinet constructed of 2 end boards, a top and bottom board, and 2 inner vertical divider boards.
The vertical dividers are a fixed distance (200mm) from its nearest end board. This dimension must not change because existing drawers must fit in between the end panel and the divider.
Each individual board is a group, and the whole assembly is a group.
I need to shorten the lengths of the top and bottom boards without changing the dimensions of anything else aside from the distance between the 2 divider boards which will get smaller by the same amount as the top & bottom boards are shortened.
The methods I found in the Knowledge Base use the Scale funtion, and do change this length, but it also causes the 200mm separation of the dividers and the end panels to get similarly smaller, and also the thickness of the end and divider boards get thinner.
This must not occur. The boards are all standard 19mm plywood, so cannot change.,
How can I do this without ‘disassembling’ (eploding) the overall cabinet group, then moving the top & bottom boards out of position to access the ends with the Push tool, then reassembling my cabinet group?
Yes, as @tweenulzeven has pointed out, you need to understand the difference between Groups and Components. I would have made any repeat items a single copied Component. I didn’t in my example because you had talked of using groups. I wanted to show how you would do it if, for some reason, you wanted to ignore the power of Components and had used Groups instead.
If I had made all four shelves a single copied Component and I only wanted to change the two I did, I would first have selected them and hit Make Unique. You would then have two pairs of Components. You could then edit the pair you need to without affecting the other pair.
As @tweenulzeven indicated, the smart way would be to use components instead of groups. Then the top and bottom, if they were instances of the same component, would resize together.
For the sort of resizing you are referring to, either Push/Pull or Move are more appropriate than the Scale tool. It’s really quite simple and quick to do. Here are some examples in which I modified a copy of one piece of furniture to make another.
Settee from Morris Chair
King sized bed from queen sized bed.
Queen sized bed from daybed
Coffee table from side table
Another option that works in some cases is to use Box Stretching from FredoScale.
Still, you should learn how to do this sort of thing with the native tools. In some cases Box Stretching creates other problems.
Especially as I don’t think he has told us which version of SU he is using! That’s why I didn’t mention any of the many plugins you could use to speed things up.