Wondering what kind of saw blade everyone uses to cut plexi sheets for windows and such. Without cracking the plexi or roughing up the edges too much. What kind of saw/blade should I use?
I use either a 32tpi hacksaw or a fine miter saw. It leaves the edges a lot smoother and you need less elbow grease to polish them. That is mainly for small scale stuff. For reall big cuts, I just score with a boxcutter and then snap it. kinda like dry wall. but that only works for 2mm-5mm acrylic.
I use a table saw all the time to cut acrylic, there is no better way for getting straight cuts. Any table saw should do the job since anything powerful enough to cut 2x4's and plywood is good enough to cut acyrlic. The key is the blade. For best results, get a 60 tooth finishing blade or, even better, an 80 tooth plysheet cutting blade. If the blade is sharp and you feed it at a decent pace, you will get no chips or cracks. For added insurance, use cell cast acrylic (the kind you would find at an acrylic reseller with a paper coating) instead of extruded acrylic (the kind you find at DIY stores with the clear plastic coating). Cell cast acrylic is much more forgiving and machinable than extruded. But even if you have the cheap stuff, you should be able to cut it on a table saw just fine. You get chips/cracks more from vibations during cutting than the actual blade itself (assuming the blade is sharp, and you should always use a sharp blade) so if you have a featherboard or some means of stablizing the acrylic while feeding it through the saw will help a lot.
Smoothe Cuts I score them like Glass with a xacto knife and the crack them. This results in a smooth cut like glass. Same way the do it at the glass companys... Look for tutorial on cutting glass. One tute 2nd
bandsaw. with whatever blade i have on it at the time, may not give the smoothest cut but works just great if the edge isnt gonna be visable. cell cast is the best, my dad scored some 1/2 inch stuff from work a while ago and it stands up to milling and latheing.
I read duct tape over where you want to cut and cut it normally will reduce heat which messes up the arcylic.
i work with coloured acrilic i asume that plexi is the same to cut and we use a fine toothed jig saw blade for detailed lines and a bench saw for streght cuts PHiRe_K
Oh what about flame polishing plexi? There was a modder on here who did it like a science and it looked
If you're using a jigsaw I recommend scroll-cut wood blades or metal smooth-cut if you can't find the previous kind. For a table saw I recommend an OBS/Plastic specific medium toothcount blade. The above mentioned blades will usually give fairly clean cut edges without excessive melting or cracking. If you get melted edges or crusty excess you can easily scrape it off with a deburring tool or by running an X-acto knife perpendicularly across the edges of the sheet. THE best tool for cutting plastic however is a nice band saw. It have few problems with melting and makes the cleanest cuts. I however do not own one because it's not a tool you can afford to buy cheaply. To polish edges you can use 300-500 grit sandpaper to remove cut marks, then either heat the edges with friction by using a the outside edge of socket head bit in a power drill or drillpress. The cheaters method for making glassy edges on plastic is to simply apply some acrylic solvent. I do not recommend polishing edges with open flames since acrylic leeches some nasty fumes, and polycarbonate will tend to carmelize if overheated. When in doubt, just use sandpaper. And speaking of sandpaper, if I need to make minor trim cuts I have a cool 250-count sanding wheel that I can attach to my drillpress. It can file away plastic like a warm knife through wax.
Well... I cut the plexi with a metal saw(don`t have a jigsaw ). But I sitck a tape on the place where I am going to do any actions. I use a tape that is kinda like paper. Sorry for the bad english. I am new here.
I use masking tape where I'm going to cut (maybe that was what nexodus talked about). I don't know if the masking tape actually does anything, but I like to think that I get a better finish with it (no chipping etc.) When doing smaller cuts/curves/internal corners I use a ~18 tooth per inch, very narrow jigsaw blade. I cut at low speed (setting 2 on my B&D jigsaw). When doing straight cuts, I use a circular miter saw. After cutting, I smooth the cuts out with sandpaper. I start with 150 or 180 grit, then 400 and then 800. This gives very smooth edges. I then use a butane torch, and just swipe the cut over the flame (not actually touching the flame). Because it is so smoothly sanded on beforehand, it goes perfectly clear in a matter of seconds, so there's not much fumes and stuff to worry about.
