Woodworking powertools to cut plexi / perspex?

[Retro_SA]

Can I use woodworking powertools to cut perspex?  Like a jigsaw to cut it smaller and a drill for the holes for the control panel?

I don't have a spare piece to experiment on...

[HaRuMaN]

I have used a table saw to cut acrylic with good results, I also used a hole saw on it with no problems.  For the hole saw, I put scrap wood underneath so I could drill through into something solid.  Just be careful, and go slow, and you should be ok.

[Tahnok]

Jigsaws tend to crack it. You can use a drill, but you're going to want to run it in reverse to melt your way through it.

Personally, I find that nothing beats a router with a pattern bit. If you're trying to put plexi over your CP, then drill your CP first and then lay the plexi under it. Then it's just a matter of routing out the all the button holes and along the edges. The router goes through plexi like it's not even there.

A table saw is good too for larger pieces (like marquee plexi). You can pull it off with most blades, but one actually designed for it is best (of course).

[IA1NY]

...You can use a drill, but you're going to want to run it in reverse to melt your way through it.

When you melt your way through, your hole will suffer greatly.  For small holes, I bought myself a set of 60 degree bits made for the job.  They work GREAT!  There's no chipping or cracking, and the hole is very smooth.  There's no melting involved.  If you're interested, go to http://www.mcmaster.com/ and search for Item # 27465A94  That's a set, but they also sell individual bits.  These can be found at most industrial supply companies too.  For large holes, hole saws work well.

Tablesaws do work great.  Use a triple chip grind carbide blade with as little rake in the teeth as you can get.  Like HarumaN said, preferably get one designed for plastics with a negative hook.  If not, just get as fine a blade as you can like a crosscut blade.  Don't use a rip blade or combo blade for it  they chip too much.  You can also cut it with a bandsaw, but it'll be rougher.  You'll have to do some sanding.

Jigsaws work okay , but you are taking a chance. 

Routers and Rotozips work well if you're looking for a hand tool.  I agree with what Tahnok said about the router.  It cuts like butter.

[AtomSmasher]

On the first piece I ever tried to cut I used a jigsaw and put huge cracks throughout the plexi, ever since I've been using a router and a flush trim bit and I will never even think about going back.  I've heard a lot of success stories with a jigsaw, but a router is just so incredibly easy and foolproof that I don't know why anyone wouldn't use it instead.

[noobofthecentury]

router can cut plexi?
I use a plastic knife, to scorn it and then split it to two

[Jdurg]

That's what I used to cut the basic shape of my Lexan covering on my CP.  Just a score along the part I want to cut, then a fold and snap and it breaks perfectly down the line.  To trim up the Lexan to perfectly fit the CP top, I used my router and it cut through it like a very hot knife through butter.

[RoninEditor]

I was gonna start a threat kinda about this it's a pretty similar question to this topic already... I was experimenting, before cutting my real holes in my Lexan and wood for the control panel.  The forstner bit did great with the wood, suuuuuper clean.  Then, as an experiment, I put the Lexan on top of the empty hole... it can out pretty clean as well, but still fairly 'jaggy'.  Then I tried it the way I intend to do it for real... putting the Lexan on top of the MDF, then drilling both.  Maybe I did it too fast but it seems really, really jaggy.  I was holding it down pretty tight to keep it steady. 

How've you guys done it?  I'm assuming locking the Lexan on top, then cutting slowly...?

[fjl]

i made the wood CP and cut the holes for the buttons then I put the plexi on top of the cp and used a bottom flush cutting bit with my router to trace the holes and cut them at the same time. Came out smooth as butter. 

[RoninEditor]

So with the cut holes in the wood, you then put the wood on top of the plexi/lexan, traced it, then used your router? 

My router skills are lacking, as far as cutting circles and patterns.  I'm hoping to stick with the forstner bit.  I wonder if do the wood, like you did, then put it on top, and then use it as a 'guide' for the Lexan, if that would make cleaner cuts.  I still have some scrap to mess around with, I'm gonna try that from the top and bottom, see if going in or out is causing the jagginess.

[fjl]

The one you mentioned you want to do IS the method I used. Re-read my previous post. Otherwise, read this tutorial...

1. Cut button holes on CP to your liking using a 1-1/8" holesaw
2. Lay Plexi on top of CP and clamp it down so it doesnt move.
3. Drill starter holes on the plexi above the cp button holes so the router bit can be used but do not drill through any of the CP wood.

4. Use a bottom flush trim bit and cut out the excess plexi to completely uncover the button holes on the wood CP. See Pic:

[Xiaou2]

 Drilling plexi in reverse is BS.

 Ive cracked several scrap pieces with the drill in reverse.

 
 To drill plexi,  go forwards.   Make sure work is clamped down well, so that there
is NO Vibrations.   Drill at the Highest speed possible.    Set the bit on the plexi like
a butterfly sitting on a leaf.   Almost no pressure at all.    It should take like a full
minute to drill one hole safely.

 As the drill scrapes, it does melt the plexi enough to cut and remove it. 

 If you run in reverse,  the plexi bunches up and doesnt get removed... and can
re-solidify - and then cause a crack.   It also creates a hole that has excess
buildup around the edges.   

 If you press down too hard & too fast, the plexi will not have time to melt enough, and the
shock vibration will cause a crack.   

 
 Use a "Drill Guide" - if you only have a power drill - as any variation in angles could
cause cracking.

 
 Razor Knife scoring is good for straight cuts.   Score must be deep enough, and must have
good clamped edge in place before snapping.

 Routers work great for cutting plexi as they are very high speed and the edge
is sharp and scrapes away material.    You can also use rotozip bits too.   Both cut
plexi like hot knife thru butter.

 You can cut using a tablesaw... however I got a rough and chipped edge.  Maybe if
I was using a finer tooth blade... hard to say.

[scotthh]

I've used a router for both holes and straight cuts and was very happy with the results. In my experience, the Lexan melts and is turned into a shower of particles similar to that which you'd find in a snow globe. As the stuff is shooting out of the router it is molten and hot. Don't forget to wear your eye protection and wear a long sleeve shirt unless you're fond of a molten plastic bath. The stringy bits that are still connected to the holes in the attached picture come off easily by hand.

See this thread or this one for other discussions about this topic.

[severdhed]

i cut my plexi with a dremel.  i used a high speed cutting bit, since i couldn't find a flush trim bit.  i drilled my button holes in the mdf with a spade bit in my drill, then clamped the plexi down on top, drilled a small hole through each one with a drill, and then used the dremel high speed cutter to trim out the button holes.  this takes a while, but works very well.  i don't own a router, so i don't know how it compares, but i would expect similar results since a dremel is alot like a small router.

[Mr Kray]

i cut my plexi with a dremel.  i used a high speed cutting bit, since i couldn't find a flush trim bit.  i drilled my button holes in the mdf with a spade bit in my drill, then clamped the plexi down on top, drilled a small hole through each one with a drill, and then used the dremel high speed cutter to trim out the button holes.  this takes a while, but works very well.  i don't own a router, so i don't know how it compares, but i would expect similar results since a dremel is alot like a small router.

Severdhed - Can you tell me what model # cutting bit you used? I'm going to be cutting my cp plexi soon and I'll probably use the dremel.

I assume what you're saying is that you start from the centre and sort of spiral out until you've cut the hole to size, would that be right? If so, do you get a nice clean cirlcle finish at the end or is it slightly off as you are doing it by hand?

[thatitalian]

Bump.

I would like to know the drill bit used. Or even where you can get it from.

[Jdurg]

I've used a router for both holes and straight cuts and was very happy with the results. In my experience, the Lexan melts and is turned into a shower of particles similar to that which you'd find in a snow globe. As the stuff is shooting out of the router it is molten and hot. Don't forget to wear your eye protection and wear a long sleeve shirt unless you're fond of a molten plastic bath. The stringy bits that are still connected to the holes in the attached picture come off easily by hand.

See this thread or this one for other discussions about this topic.

I wound up doing the same thing to mine.  Did the rough "cut" of the straight edges by scoring and snapping the Lexan, then clamped it down to the CP and used my router to route out one hole.  I then went and put a button in and routed out all the other holes.  Lexan routed out perfectly.