Cutting & glueing Acrylic

[brian fithian]

I am cutting some letters out of acrylic and glueing those letters into cut outs on a different color acrylic. What type of glue works best to fill in the " slack space " between the two. The space is to large for weld on. I want that void to be completely filled because it will be back lit when finished.

[Paul Phillips]

Brian, are the top set of letters clear or solid color? If clear it will be very difficult to get a good bond with no bubbles or visible defects using glue, you would probably need an optically clear adhesive on the back of the top set of letters such as - http://solutions.3m.com/wps/portal/3M/en_US/Converter_Solutions/Home/Prod_Info/Prod_Catalog/?PC_7_RJH9U5230GE3E02LECIE20GER4000000_nid=K80S7PS HP6be4Q43M9FFQ2gl
or if the letters are a solid color you could use some Weld-on #16 which is a thicker, slower drying glue and will work better at filling those voids.
Hope this helps.
Paul

[Joe Pelonio]

I would suggest turning it face down, insert the letters and apply clear vinyl film over the whole thing to hold them in place. Then place a sheet of clear 1/8" acrylic over that and tape the edges with clear vinyl, and trim so it doesn't show on the front. That will hold it all together. You will get more light around the letters in the crack. No way around that unless you fill from the back with black silicone using a squeegie and manage to scrape/clean off any excess.

An option that comes out nice it so cut the letters thicker than the background so they protrude, say 1/4" letters on 1/8" background. You could also apply cut vinyl letters (mirror image) to the back, spray with translucent paint, peel off the vinyl when dry and backlight. Or most common/cheapest, just apply translucent vinyl with the lettering cut out in mirror image to the back of clear acrylic.

[Phill Barnes]

Hi Brian
Many years ago I made an acyrlic clock. The face was clear and the numbers and center were translucent blue. I made the numbers a press fit and need no glue at all as they had to be tapped in gently with a block and mallet. To achieve this, you simply need to add a contour line to the parts to be inserted, break the contour group apart and remove the original and cut the contour line. Don't forget to keep the original so that you can adjust the contour step. You will have to do some experimenting with the contour offset as all lasers are going to be different. It was a long time ago but the offset was something like .002 mm I think. Do some tests on scrap but remember if it is tight enough that you have to really bash it in, it will probably crack something. By the way, I work in Corel Draw.

PHILL

[walter hofmann]

Hi
I make my own glue from scrap acrylic the same what is use to cut , then I disolve it in Aceton in a glass works amazing allclear.
greetings
waltfl

[Mike Null]

Walt

Isn't it still visible?

[brian fithian]

Thanks for all of your help. Many good ideas, will experiment with a few of them