Gluing acrylic sheets on to other acrylic surfaces, or surfaces made from other material for that matter, is not as simple or as straight forward as it sounds. This is not to say that it is difficult or arduous in anyway, but you will need to meet several specific conditions before you can go ahead with the gluing.
If the conditions are not met, the best case scenario is that the acrylic will simply not adhere to the intended surface; the worst case scenario on the other hand is that the acrylic sheet will craze. Crazing makes the acrylic appear white, but on closer inspection you will see what looks like dozens of spider-webs overlapping, almost like the material is covered in tiny little cracks. Needless to say, this has an extremely negative effect on the aesthetics of the material and may possibly render it useless.
When gluing one sheet of acrylic to another you will not want to use super glue or any other standard adhesive. If you want to do the job properly and form the strongest bond between the materials you are best off using acrylic cement, which can be found in most hardware or hobby shops. Acrylic cement does more than simply glue the pieces together, it actually causes the molecules that make up the two to bond together, fusing the sheets together.
Preparing Your Acrylic
Before you even get started it would be prudent for you to ensure the surface on which you will be doing the acrylic gluing is appropriate and safe for fulfilling this purpose. It should be noted that the only surfaces that you should attempt to glue acrylic on is wood, metal or concrete; it is not a good idea to do any of this kind of work on a surface that contains glass or paper; even if you are only intending on using them to protect the work-surface or table.
Now that we have gotten that out of the way it is time to make sure that your acrylic sheets are prepared and ready to go. The condition of your sheet's edges is of paramount importance; you must ensure that they are as smooth as possible, as any bumps or indentations may hinder your progress. It is important that you remember this as acrylic cement is not as accommodating as regular glue, and it will not run and fill any holes or gaps that the acrylic has.
To make sure the edges are prepared properly simply sand the edges down with sandpaper until they are smooth and square; acrylic cement will not work on edges that are rounded, so make sure that when you're sanding the edges that you are doing so on a study, flat surface. Once you have done this and your edges are nice and square, give them a quick clean to remove any residue from the sandpaper or the acrylic.
Gluing Acrylic Sheets
You need to be very precise when gluing acrylic, so accuracy is important. Make sure you take steps toward guaranteeing that when you do apply the cement to bond the sheet to the intended surface, that you do so exactly where you want it to be. Once situated, apply the cement to where the two sheets meet, pushing down on the two sheets whilst the cement runs between the edge.
Hold the sheets in place for several minutes, giving the cement enough time to create some semblance of a bond. Once you feel you are able to let them go, do so and set your project aside for around 48 hours. This will give the cement ample time to fuse the sheets together, creating a strong bond. You can tell if the cement had dried as it will be fully transparent.
That is all there is to it. If you wish to trim any overhanging materials feel free to do so, and do not worry about the cement coming unstuck, by this point it will have hardened and you would have a hard time separating the two.
We hope you have found this guide helpful and good luck on all your future projects!