lasering pint glasses

[Noah Grant]

I do laser and sandblasting for glass and ran into a small issue. When you laser on pint glasses with a rotary I know you can raise one end to get it level however when you laser an image it still comes out distorted. Is there a way to fix this? It basically comes out long and I know its because the lower the glass the smaller the diameter. I can always resort to wash out photo resist but I am looking to speed it up with the laser. Thanks for the help!!

[Martin Boekers]

I think you still will have issues with the resist, I find on circle logos I do that I have to stretch the sides a bit to give the "Illusion" of it being round.
Since the laser is 2 dimensional and the glass has a three dimensional curve it "seems" like it compresses the image when looked straight on.

[Keith Winter]

You're doing some long artwork and hitting the taper of the glass I think you're describing, not much aside from buying a wider glass can be done, or using a glass that doesn't taper. You could try to warp the artwork to compensate in corel but that's likely going to take a lot of trial and error I would think.

[Ross Moshinsky]

Lasering glasses on small runs may be quicker but on a production run, if you're experienced, sandblasting should be much quicker.

I have two easy solutions to your problem. Shrink the artwork and/or set the focus and set the diameter to whatever the diameter is on the glass at the midpoint of the graphic, give or take. That should help quite a bit. If neither of those solve the problem, you're going to have to warp the image. There are a bunch of posts about it from several years ago. You should be able to dig up the answers after about 10 minutes of searching.

[Tim Bateson]

From Epilog (With a few tweaks from me): Divide the drive wheel/chuck side by the middle (engraving area) diameter and multiply by 100 for the % of adjustment. If < 100 : shrink artwork (only in 1 axis). If > 100 : expand artwork (only in 1 axis).

[Real Mercier]

This is a Excel sheet that figures out the calculations of what the graphic distortion should be. I have only used it a couple of times but with vector files. I haven't used it with bitmaps. I would suspect that Corel lets you play with perspectives in 3D effects. PM me if you have any questions about the sheet. Let us know how it works with bitmaps. It works well with vectors.

Hope this helps.

Real Mercier