Two sided engrave

[mprather]

I’m engraving a large piece and was wondering if I flip it over in the same exact position what are the odds that the engraving will line up again in the same spot as it is on the other side?

[eflyguy]

If it is lined up (i.e. back inside the material it was cut from that was pinned in place, or with some other bounding jig), it will be accurate to within 1/1000".

Edit - within the limit of the kerf, of course, which is much wider than 1/1000… Also - I posted a pic/tutorial on this somewhere, but for an irregular shape, I make a mirror of the cut outline and cut the extra section out. That way my flipped part drops back in. Someone else pointed out that for making sure things like circles have the correct rotation, cut them out as a square or with a “key” after the first engrave, then the complete or cut circle after the back-side engrave.

[evansd2]

Glowforge Interface - How to Align a Double Sided Engrave

I’m going to demo an alignment process below using my (ancient) version of Adobe Illustrator, but the process is the same for Inkscape or CorelDraw or Affinity Designer. Whichever one you like to use, you’ll do the same things, with the tools in that program. (I’m also going to give you the thought process that goes into creating a design with 2D Design software, to keep from having to write another one up, so if you can slog through it, you’ll pick up some stuff you need to know to make thing…

[rbtdanforth]

@mprather

if I flip it over in the same exact position what are the odds that the engraving will line up again in the same spot as it is on the other side?

I do that alot. You want to have a shape that is symmetrical so it looks the same when flipped, and an outside shape that will lock it in. Here are a couple examples of what I am talking about…

Note that when things get too thin they can burn or melt.