Posted by georgesbasement on Dec 05, 2017; 2:50pm
URL: https://forum.librecad.org/Practical-matter-Increasing-the-spacing-between-objects-in-a-drawing-tp5715556.html

After more-or-less successfully having a couple of small (about 75 square inches, 0.25 inch thick) steel plates laser cut from my LibreCAD drawings this Fall, I am about to go to the next phase of my project.

Trouble is, my very cooperative vendor warns me that he'll need bigger margins on the drawings - the parts to be separated from each other are too close together. My latest drawings have about 100 parts, all to be disks destined to be made into small gears of 48 diametrical pitch, so I really need to heed his advice, or my little gears won't have good teeth.

It would be a herculean task to redraw & rearrange all those multi-sized disks, so my plan is to scale up my drawing by a factor of about 1.15, thereby enlarging everything by that factor, and then to select each individual disk and scale it back down to its original size with a scaling factor that is the reciprocal of 1.15.

Question: How do I make sure that each entity stays in the same relative position so that the margins between the entities are not upset ? My intention is that the distances between the centers of the entities be proportionally increased according to the original distances, which ought to increase the margins between the pieces in a consistent way.

An aside: As cut, the edges of the steel parts are so hard that they damage the steel files that I use to trim the remainders of the tabs by which they were attached to the original plate. I have learned that the convenient way to temper the hardened edges is to heat the parts with a hand-held propane torch to a temperature hot enough to coat the parts with blue-black iron oxide. Not bright blue - about 500 Fahrenheit (F)-  but blue-black -  about 1000 F. Then the filing and presumably the ensuing machining are uneventful. The tabs are necessary to keep from dropping the parts into the bowels of the laser-cutting machine.

Thanks
George