Above: Un-polished acrylic edge as it is after being cut by a saw
Being an extremely versatile material acrylic can be used for any number of projects and in many different ways. It is safe to assume that different facets of acrylic’s resume will be focused upon, depending on what the project requires; it may have been picked due to its damage resistant properties, its cost, transparency, workability and so on. But no matter what it is being utilised for one thing that most people will want to ensure is that it has a good aesthetic.
The first step toward ensuring that your acrylic sheet will still look its best even after you have finished cutting, drilling and generally preparing it is simple: leave the protective film on as long as possible. The protective film which we are referring to is adhered to both surfaces of our acrylic sheets and will already be on when they are delivered; which makes the first step a very easy one to follow, as you don’t have to do anything!
Just in case you’re wondering why you ought not remove the film; acrylic boasts a high resistance to damage so it is hard to break, but any abrasions caused by an impact or if its surface is scratched in anyway the marks will be highly visible. Depending on the depth of the scratch these wounds can be effectively closed by scratch removal solutions, but ideally you will want to avoid causing yourself the additional hassle.
An important point that you should take note of is that the way in which you machine and cut your acrylic sheet will have a profound effect on the time taken and the ease with which you can clean and polish the acrylic edges. Sawing or cutting acrylic will leave the edges rough and serrated, and you may be compelled to want to smooth these over. If this is the case please bare in mind; the more cleanly the cut is made the less sanding will be required of you, it is that simple.
To ensure you get the cleanest cut possible we recommend that you use a saw with fine, closely spaced teeth; as wide spaced teeth will actually chip the acrylic. There are blades out there that are designed specifically for cutting acrylic and if you are able to get your hands on one of these blades you will have nothing to worry about. If you are sawing by hand we strongly suggest you use a guide, as trying to level out a sheet that is cut at a gradient by cutting it again could end badly and levelling it out with sand paper will take you just short of forever.
So you have now cut your plastic sheeting and are considering how you are going to polish the (hopefully not too rough) edges. Polishing acrylic edges is not difficult but, as stated above, the process can be time consuming and if you use the wrong tools you can severely damage the material.
But before we get to that we should point out now that once the edge of an acrylic sheet has been polished it cannot be glued. Just to emphasise the point, if you try to glue a polished edge the plastic will craze and the aesthetic of the acrylic will be irreparably damaged. If the edges are already polished and you want to glue them, try scuffing it with sandpaper as this may prevent it.
Back to the topic at hand, you will need to use the right materials if you intend to polish acrylic edges with any degree of success after cutting. Sanding is the natural go to method in situations such as these, but in this case you will want to wet-sand the material, which means you will require water as well as waterproof sandpaper. As you should be using water during sanding, we vehemently suggest that you refrain from using electric-based tools, as that could end rather badly for you.
The sanding process can be time consuming but it will be worth it. You will not want to use just one type of sandpaper, as after you have smoothed the edges you will want to make a start towards giving it a polished finish. To start off with you will want to sand the edges using a quite a coarse sandpaper and slowly move toward using finer and finer alternatives.
The coarseness of sandpaper is classified by its ‘Grit’; the higher the grit, the finer the paper is. You will want to begin with a grit of around 180, which is the type generally used for smoothing out wooden edges and surfaces. Once you are confident that the edges are level and smooth to your satisfaction you can move onto a grit of 320/360, which is an extra fine kind of paper that is normally used to give wood a polished finish. After which you can move on one final time to a grit of 600, which is considered super fine.
If done correctly you should be left with a smooth polished edge, but you can take it a step further if you would like the edges to be highly polished. There are waxes, pastes and other solutions that can be used to bring a fantastically bright, polished finished to the acrylic but be careful when selecting which one to use as if you get one that is too abrasive you will end up ruining all the work you have done up until now. If you have access to one, a buffing wheel is a great option to consider using to give your work its opulent finishing touch.