Cutting plexiglass to a pattern

[CarvedTones]

I have a pattern on plexiglass. It is straight lines, but there are V shapes so I don't know if scoring and snapping would work. I tried scroll saw and jig saw on part of the waste to test and it melts it enough that the scroll kerf is welded back completely and while the jig saw cut could be snapped away, it was rough. I need clean edges left behind.

Advice?

 

[Mark Gottesman]

Can't help a whole lot here. I have made a fair amount of templates for sheath knifes. Usually use 3/16 - 1/4" and have cut it with a bandsaw (14") and a coarse blade. I cut oversize and file back to the line. If you are melting your line closed then you need a slower speed. the jigsaw and scroll are a problem since the are prone to clogging and the packed chips just raise the temp in the cut.

Maybe a small trim router with a spiral cut bit? Depending on the size and how many you need to do I would consider a coping saw and some files.

HTH

 

[Mike Davis]

When I had my sign business I would cut letters out of plex. I used a scroll saw with fine blade, very slow speed and an air nozzle directed at the cut to keep it cool and clear of cuttings. To finish off the edge a butane torch set to very fine flame swiftly passed across the edge would make it clean and polished.

 

[ehpoole]

FWIW, you can also take a router to plexiglass if need be. Ideally dial the speed down a little and keep the router moving quickly in clean smooth motions. Use sharp carbide or HSS bits and the plastic mills quite easily.

If your jigsaw blade is melting the plexiglass that is a sign that you are generating too much heat, odds are a slower speed and perhaps some wax on the blade and you should get more favorable results.

 

[sawduster]

2 or 3 layers of clear packing tape on the line, cut slowly and at slow speed with a reverse cut blade and the air blowing just behind the cut . The tape will help lube the blade and keep it cooler

 

[jerrye]

It's not the fastest method, but the best method I have found for straight cuts is a finer toothed pull saw. Cuts any thickness, and cuts clean. Lowe's sells the Vaughan saw that should work well for this.

 

[ehpoole]

You don't really go into any detail on the straight cuts, but it occurs to me that I should have probably mentioned that the tablesaw (as well as the bandsaw mentioned above) are also well suited to cutting plastics. Most any tablesaw blade will do the job for straight full-depth cuts, but for partial depth cuts you'll need a flat top grind or dado blade if you want flat bottoms.

Still, the router is one of my more favored tools for milling plastics as it is just too easy, though it does help to wear long sleeves so that you are not startled by the hot plastic striking you. It won't burn you but it can be uncomfortable, especially if you are not expecting it. The router tends to yield very crisp edges with little if any cleanup work unless you want optically polished edges.

 

[Weekendworrior]

I cut my fair share of plexi in the bandsaw. I coat the blade with silicone spray and cut at high speeds. I've cut up to 1/2" plexi..........intricate cuts...........on the bandsaw with a blade made for 1/4" and less thickness with no melting issues. Spray as you go if necessary. There is only a need of reduction of friction.

 

[CarvedTones]

No bandsaw right now. After testing a few options on waste, I ended up using my jigsaw on a slow, but not slowest, setting with a 14 TPI skinny blade and a little oscillation (one click away from none). The last things surprised me - I expected oscillation to be a problem, not a solution and if I turned it all the way on it was. But having it barely on helped clear the cut.

 

[john frazee]

I cut plexiglass with my laser. It will cut any shape and will even laser etch a photo into it. I use 1/8 in but have used 1/4 inch. My laser table is only 12x20 so I am limited to the size of projects. A frien of mine has one that he puts 1/2 shett of plywood in. Nice! Laser cutting plexi leaves a nice smooth edge.

 

[Vetteman9956]

I agree with John, my laser does a great job of cutting acrylic sheet. I cut many sheets a month.

 

[CarvedTones]

Brad,

If that's an offer, I will keep you in mind if this comes up again.

 

[CarvedTones]

and there are the glasses I was cutting from the plexiglass. This is at Animazement.

 

[CrealBilly]

I cut some plexi guitar patterns. It took me a couple tries to get it to work. I used my jigsaw set on low speed, a all purpose blade (I can check the TPI if you like) and good 3M (thick) masking tape. I roughed the pattern out and got it close with files and 60 grit sand paper glued to various profiles. What really finished it off was when I used my propane torch to smooth out the file and sanding marks. You don't need to apply a lot of heat or else you'll melt the pattern (just wave it over the edge). Seemed to work pretty well, once I got the hang of it...