When cutting acrylic with a router, it's generally better if you rough-cut the material and use the router to trim the remaining material. You can use the router or any other saw for the rough-cut. If you are cutting through a large panel and want a fine finish on the cut, you need to support both pieces of the panel.
I had been doing some work with plexiglas lately and found some good ways to score and cut, drill holes in, and bend plexiglas. I wanted to create an instructable on how to properly perform these tasks but thought I needed to actually make it into something to make it interesting.Plexiglas is a very cool material, a clear, tough plastic that can be used for a variety of projects from see through cases, to a pseudo blast shield, to the tripod I will teach you how to make.
While it's not technically a tripod it serves some similar purposes. By itself it can hold the gopro on top to gain a little more height. The gopro can also be hung underneath if you are trying to show how to repair something on a car and the plexiglas will protect the camera from harmful slag while welding or grinding. Also with the new wifi live view function through wifi on the Hero3 cameras the 'tripod' can actually be used as a cover over the gopro that holds your ipod or phone on top.
![Cut Cut](http://demandware.edgesuite.net/aaea_prd/on/demandware.static/-/Sites-cpo-master-catalog/default/dwaeb247ff/product_media/dew/dewndcg412b/images/360/dewndcg412b_N1-1.jpg)
Cutting plexiglas is often hard to do cleanly, this is why I felt I should pass on how I have been doing it as it works very well.For this step you will need the scoring tool (Or box cutter or x-acto knife), the ruler and the quick grips.You will begin by scoring the plexiglas. This part is crucial as where you score is where it will be 'cut'. If your line is crooked your 'cut' will be crooked. You must also take special care to cut clear to both edges, if you don't cut the edges it will shatter on the ends and destroy all of your work. The way I have found that works the best for this is to clamp down the ruler where you want to score and make sure to get the metal banding on the ruler on the side that you will be cutting. Once you have your guide attached you will begin scoring.
Push your scoring tool up against the metal edge and pull toward you, little spirals of the material should come out as you go. You will score the piece several times. From what I've found, the longer the line you're cutting the more times you'll have to score. You will need to score roughly 10 times with the tool. Also the scoring tool is fastest, you will need to make roughly 3 times as many passes with a box cutter or x-acto knife so I'd recommend picking up one of these scoring tools. They're only about 5 bucks at Menards and they work really really well. After scoring you will need to bend the plexiglas on the line until it breaks off.
The score lines make this much easier to do and also ensures a nice clean edge rather than something that looks like it was chewed off. You will want to keep the ruler from the scoring step on, it will help keep your edge from breaking anywhere but the score line. You will then line it up so that your score line just barely sticks off the edge of a counter or workbench that has a hard 90 degree edge rather than a rounded one. This will also help make sure it cracks on the score line. Then you will start bending the plexiglas by pushing down on the part sticking over the counter.
When doing this the score line must be up otherwise it won't work. You will continue bending until, in one big crack the piece you scored will pop off with a nice clean edge.
If you can't get it to crack you will need to score it more. Then you can remove the ruler by releasing the clamps. Often with plexiglas, you will try to drill a hole and it will shatter or crack. One way to avoid the cracking is to drill a smaller, pilot hole. You must also be careful when you do this though as a small hole can still cause a crack. The best way I have found for drilling into plexiglas is getting the bit spinning as fast as your drill will make it go and then just barely pushing on the plexiglas.
![How To Cut Plexiglass How To Cut Plexiglass](/uploads/1/2/4/3/124342724/538439595.jpg)
If you push too hard the cutting part of the bit will grab a lot of the plexiglas and it will torque the material and crack or shatter it. Choose a nice small bit and drill your hole.
When bending plexiglass you will need to have a straight edge to make sure you get a nice clean bend. I used the ruler and the clamps from the first step as my guide. You will go ahead and put your ruler on where you want to bend it and then clamp it down. If you want a gentle rolling curve you may want to use something like a coffee can and then heat the whole piece and form it around the can.
I however just opted for a nice small curve. You must be careful to place the ruler on the correct side, you will be essentially bending it around the ruler so if you are going to bend down (Like in the picture below) you need to have the ruler on the bottom. Now that you have the form clamped down the guide for bending you will want to plug in your heat gun. The gun I have is designed for doing the plastic like wing coating on model airplanes and being such it has a sort of fan tip. This helps as you can use it just to heat right along the line you want to bend, if you don't have the nice fan tip you may want to make a sort of heat shield or just be careful bending as you will have a much thicker band of semi molten plexiglas. Heat the plexiglas until it is malleable, then carefully begin folding it over the ruler. Since the temperature difference between melting and the point at which it becomes workable is rather large, you can easily get it to malleable without melting it.
Since it's not actually melted you can pull the end taught so that the edge stays crisp. Once you have it to the desired angle I've found it works best to put the part you were holding onto down on a surface and put the guide down against it.
Again you can tug on the end to sharpen the curve to your liking. I am still finding uses for this interesting looking stand. I have been using acrylic for over 30 years and the way in which you describe drilling a hole is not the best to get a clean hole. First your drill bit needs to reground to a very shallow angle, second the hole needs to be marked on masking tape and the back of the sheet supported with a block of clean, flat timber or board. Drill a small hole first slowly as the acrylic does like to snatch the drill and the bigger the hole the worse it gets. Gradually increase the drill size and drill slowly with very little pressure.Bending acrylic is best done with a strip heater or line bender but you can use an ordinary oven set at 120-160C use a jig or former to get the angle correct. Never use water to cool the acrylic as this will make the acrylic brittle.Scoring is the best way to cut the acrylic in straight lines and then snap it like you do with glass.
Cutting curves is bes done with a mechanical saw and protect the edge/line of cut with masking tape as this prevents the material welding itself back after the saw balde has passed. Not bad, I could never get the score/break to work properly. I'll try again. I usually tape both side with masking tape, mark my line and use a jigsaw with a metal cutting blade. I'll clamp a level in the proper place to use as a guide.
Keep saw butted against level and you can rip a nice straight cut. Tape seems to minimize the chewed edge. If I want to mount hardware on plexi, like hinges or clasps. Pop rivets are your friend. Screws tend to break it. Nuts & bolts look too 'frankenstein' for my tastes.
Drill hole just big enough for rivet, try to put a washer on the back side (I've done it without them with fine results) and pop it. A nice solid and clean looking fastener. The only other tip I have is to use scrap pieces to test a technique first. There's nothing worse than to be on the last step and crack your finished piece because you didn't factor in something.