Cutting acrylic plastic for case? Would a dremel or drill+milling table work? - Page 1
Forum section: electronics / beginners

author: cdev
author_rank: Super Contributor
timestamp: November 08, 2018, 03:28:56 pm
content: I have some clear and also some UV fluorescent colored acrylic plastic material I would like to use for electronics cases if it's possible to do it neatly.What do people use for something like this, besides a laser? All the pieces of plastic I have appear to be between 1 and 2 mm thick.I have a dremel, also Ive thought about using my drill press horizontally. I could likely do straight cuts with that- Because its pretty plastic, however, I would like to get a nice smooth cut. Maybe its possible to do that with some kind of abrasive lubricant?

author: JackJones
author_rank: Regular Contributor
timestamp: November 08, 2018, 03:44:20 pm
content: I just use a hacksaw. You do need to clean the cut with sandpaper but I've never really had any problems.

author: cdev
author_rank: Super Contributor
timestamp: November 08, 2018, 04:04:37 pm
content: How do you get straight cuts? I have never been so good with a hand hacksaw as far as it looking good cosmetically. On wood, etc, my cuts always wander a bit.

author: JackJones
author_rank: Regular Contributor
timestamp: November 08, 2018, 04:18:13 pm
content: I guess it's just a matter of experience. Once you get some practice in you should be able to get a pretty nice cut.

author: Fred27
author_rank: Unknown
timestamp: November 08, 2018, 04:54:01 pm
content: Acrylic cuts really nicely on a CNC mill/router without any lubricant. I'd have thought using your pillar drill would be OK if you used an endmill in it. Not ideal to have lateral loads on the bearings but it should work.

author: Benta
author_rank: Super Contributor
timestamp: November 08, 2018, 05:16:32 pm
content: Dremel: No. It runs much too fast and will melt the material.A mill/drill with a fine toothed slitting saw is perfect for this job and will make straight and fine edges that you only need to touch up with a fine file and very fine sand paper.Make certain the mill head is trammed correctly, otherwise you risk cracks.

author: cdev
author_rank: Super Contributor
timestamp: November 08, 2018, 05:24:22 pm
content: Thank you. I dont think the lateral force in the drilling plastic scenario is likely to be that strong compared to metals.I may still have some kind of lateral cutting bit, I bought at one time a long time ago for some other material (and my hand drill)So, no kind of fluid etc, is needed-

author: Richard Crowley
author_rank: Super Contributor
timestamp: November 08, 2018, 06:01:04 pm
content: I use a mini table saw for cutting acrylic (and aluminum) ...https://www.amazon.com/gp/product/B005FI3MKCThis one is rather more fancy (and expensive) than the one I got a few years ago. Feature/price creep.

author: cdev
author_rank: Super Contributor
timestamp: November 08, 2018, 06:36:10 pm
content: Cute.. that looks like it would be ideal..is that a rotary saw or jigsaw or small band saw?

author: Richard Crowley
author_rank: Super Contributor
timestamp: November 08, 2018, 06:44:32 pm
content: It is a scaled-down table-saw with a circular blade, etc.You can get many different blades including diamond and carbide-tip.

author: cdev
author_rank: Super Contributor
timestamp: November 08, 2018, 06:51:08 pm
content: Proxonn is insanely expensive and some of their tools bear a superficial resemblance I think, perhaps to Liyang, a Chinese brand. They make little saws like that.They appear to be a huge company - at least from the variety of stuff they make they seem to be so.

author: KL27x
author_rank: Super Contributor
timestamp: November 08, 2018, 07:11:09 pm
content: QuoteCan be done with a hacksaw, no doubt. If you don't have a garage full of tools, you might want to take a look at a small dozuki type of hand saw. This is kinda like a western style miter saw, but cutting on the pull instead of the push.1. thin, thin kerf, because it cuts on the pull stroke it doesn't need a thick blade to keep the blade straight. This kerf means less work.2. it is a back saw. Meaning it has a rigid spine. Perfect for straight cuts through thin material. You can cut unlimited stock size, since there's no frame to limit the cut depth/length. Keep the angle of the cut shallow so it is self-guiding through the cut. The saw much closer to parallel to the sheet than perpendicular.3. Fine sharp crosscut teeth leave a great finish in plastic. A hack saw or a western miter saw has set on over other tooth or whatnot. The teeth are the same shape, though, 90 degrees to the sides. The dozuki has every other tooth sharpened the other way at an angle, and is just crazy sharp and efficient.Many hobby and craft stores sell tiny versions of this saw. I didn't know the origin or proper name until years later. On Amazon US you can search "mini dozuki" and get Amazon's choice for 15 dollars.A tablesaw is the most efficient way to cut this size of stock (which I imagine) down, but you can't buy a good table saw, cheaply. If you want the best edge possible, it won't come off a table saw, anyway. A 2 flute endmill is the stuff of dreams. In the US, you can buy a craftsmen router and table combo for $150.00. It's not the best way to cut acrylic sheets down, but no matter how else you do it (say score and snap), you could quickly dimension and finish the edges on the router table. For larger pieces, hand router and straight edge. And you can do shaping, inside openings, slots and rails, for starters.

author: 6PTsocket
author_rank: Regular Contributor
timestamp: November 08, 2018, 09:08:35 pm
content: I don't saw or mill it at all. They sell plastic scoring knives for a few bucks. Any craft or big box store should have one. I think mine is Olfa, a good Japanese company. Just take a straight edge and make severeral deep scores and it will snap off clean as a whistle; at least as clean or cleaner than a saw blade. No melting, no plastic dust, no waste. If the edge is going to show, you can sand and polish it but you have to do that no matter how you cut it. When you snap it, do it over a square edge, right under the score line. I cut acrylic for framed pictures with no problemSent from my SM-G900V using Tapatalk

author: Teledog
author_rank: Regular Contributor
timestamp: November 08, 2018, 09:43:20 pm
content: Ideally, a band saw is what I use.As 6PTsocket stated, I have scored the plastic, both sides with a carbide blade, takes a while..use a taped/secured straight edge, works OK.. esp. thinner stuff.Use a sharp edge for the final break- while clamped.A variable speed jigsaw MAY work, if it's well clamped -close to the cut.After that..for a straight edge, a belt sander is ideal, other than that..good old sandpaper, then finer "wet & dry" sandpaper on a glass/flat surface.For a fine finished edge, use the wet & dry sandpaper - wetted, 120 & work to ~200-400-ish grit, then for a very nice edge finish, use plastic polish (I use Novus, good stuff - fine version works well- also works very well for your dull plastic car headlights).To glue it, use methylene chloride, hold the edges together & apply dropwise with a ~18-20 Ga needle syringe to the very edge (careful not to slop, as it will dull any parts you don't want it on) & hold it for ~30 seconds.Methylene chloride is available at plastics shops..and also some neon sign shops..don't need much at all- 100ml should be more than enough for a few small projects!And keep it well sealed..it evaporates like nobody's business!G'Luck!

author: 6PTsocket
author_rank: Regular Contributor
timestamp: November 08, 2018, 10:27:24 pm
content: Quote from: Teledog on November 08, 2018, 09:43:20 pmMethylene Chloride is the active ingredient in many paint strippers. The EPA is pushing to get it banned for non commercial sale. Lowes took strippers containing methelene chloride off the shelf. I would imagine a few drops are not nearly as risky as slathering it all over a piece of furniture. They say there are a few confirmed deaths from it but who knows. I never knew what the solvent was for plastic cement. Mention of certain substances like benzine and methelene chloride always catch my eye.Sent from my SM-G900V using Tapatalk

author: KL27x
author_rank: Super Contributor
timestamp: November 09, 2018, 01:52:54 am
content: Honestly, I just cut a piece of 1/8" acrylic in my garage with my dozuki, just to make sure I'm not full of it. I now have a garage full of power tools. So it's been awhile since I hand-cut acrylic. These days, I use a bandsaw and router table.Beau T ful cut, right on the line. Engineering square straight. It takes time to do, but very little skill or effort. So if you can stand in one spot for a few minutes, you can make beautiful cuts with a dozuki. (Reminds me of when I cut a dead 4" thick tree with the big boy pull saw.... It took five minutes, but I did it with one hand while smoking a cigarette with the other and not breaking a sweat, lol).The cutting angle I used for the sheet is so flat, I just held the sheet over the edge of a cutting board to keep from sawing into my bench. You could do this anywhere, in case you don't have a good bench corner/edge for your handed-ness.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: November 09, 2018, 04:11:24 am
content: I would definitely score and snap it. Fast. Easy. Clean edge. No fumes. No fouled up tools if you go to fast and melt the plastic. 2mm is getting towards the thicknesses where I have difficulty with the scoring and snapping technique, but is on the right side of that border. Some folks are successful up to 6 mm or more.

author: Fludo
author_rank: Regular Contributor
timestamp: November 09, 2018, 12:53:20 pm
content: Quote from: cdev on November 08, 2018, 04:04:37 pmA hacksaw is thin and fine toothed for cutting hard metals like bolts and steel. For a straighter cut you will need a wider blade and less teeth per inch. Try one of the all purpose back saws/panel saws from the hardware store.

author: 6PTsocket
author_rank: Regular Contributor
timestamp: November 09, 2018, 06:02:30 pm
content: Quote from: CatalinaWOW on November 09, 2018, 04:11:24 am2 mm is about the .08" thickness of the lucite/plexiglass/acrylic sheets that I regularly cut up for picture frame "glass". No trouble with a scoring knife at all. You can also flip clear plastic over and score both sides and it will almost complete the cut.Sent from my SM-G900V using Tapatalk

author: Buriedcode
author_rank: Super Contributor
timestamp: November 09, 2018, 06:08:49 pm
content: Whilst many recommend hack saws, I would go with a razor saw with 32tpi. Much thinner, and whilst it has no real advantage for thicker (>3mm) plastic, it makes quick work of thinner stuff - and it leaves very smooth clean cuts. I clamped the piece down with a metal ruler along the cutting line as a guide - each back stroke cuts about 8mm on 2mm acrylic.For stuff that thin you could easily just score both sides and snap. The edge won't be very nice but a few passes with a decent file and you'll be golden. The edge finish is fine if you're using acrylic cement, but if you have exposed edges, flame polishing works wonders - plus its quick.

author: Brumby
author_rank: Unknown
timestamp: November 10, 2018, 01:04:40 am
content: My observations:- Straight cuts with hand tools require skill. Anything longer than 2cm or so and I know I'm not going to be happy with my results. I just don't do enough to warrant purchase of specialised tools or to get the experience. I like jigs or mechanised solutions.- Anything that grinds or abrades has to have the speed kept right down - otherwise (as others have said) the plastic will melt and you will end up gluing the material to the tool. That gets very frustrating very quickly.- Cutting tools are by far the best - but you need to:* have sharp cutting edges* support of the material as close to the cutting zone as possible* take small bites- Score and snap can work well for full length cuts (no good for internal corners) - but practice first so you know how well you need to score for consistent results. If you don't score properly, you might find yourself with a cut that is fine for part of the cut and then wanders off line. Murphy's Law will ensure such wanderings will run into the target piece, not into the waste which you could sand off. Even then, sanding off can leave a different finish to the edge that can sometimes be irritatingly obvious.I'm looking at building my own laser cutter which could take care of this. (I know you can buy them - but for the work area I need, they are prohibitively expensive. Plus I don't requirethatmuch engineering.)

author: not1xor1
author_rank: Frequent Contributor
timestamp: November 10, 2018, 07:26:03 am
content: I use a Bosch PKS 16 multi for wood, aluminium, and various kind of polymer sheets.https://www.bosch-do-it.com/gb/en/diy/tools/pks-16-multi-3165140651240-199896.jspYou just need an aluminium bar guide for straight cuts.It does allow you to get straight and reasonably polished edges.

author: tooki
author_rank: Super Contributor
timestamp: February 11, 2019, 02:05:18 pm
content: Quote from: cdev on November 08, 2018, 06:51:08 pmProxxon is only insanely expensive in North America (or perhaps outside of Europe in general). Within Europe, it's actually eminently affordable, being even cheaper than imported brands like Dremel.If anyone is copying anyone, then it's the Chinese copying the Germans/Luxembourgers. Proxxon has been around since 1977.

author: Rick Law
author_rank: Super Contributor
timestamp: February 12, 2019, 03:05:23 am
content: Quote from: 6PTsocket on November 08, 2018, 09:08:35 pmAt Home Depot, they sell plexi-glass, and they sell plexi-glass acrylic cutting knife similar to the picture6PTsocketposted above.Some years back, I had a project using plexi-glass. I use one of those to cutting quite a number of 1/8" thick plexi-glass sheets. Worked very well - I cut quite a number of them (making many smaller and smaller sheets out of 4 big ones). Much better than saw which tends to create cracks. You just need to make sure your first cut (initial groove) is nice and straight, then you can work it deeper and it snaps nice and clean.I understand that plexi-glass while in the same family as acrylic but is different. I think they share enough similarity in property that what works well for plexi-glass should be worth a try.

author: Old Printer
author_rank: Frequent Contributor
timestamp: February 12, 2019, 04:52:44 am
content: I work at an architectural sign company in production. We use a lot of acrylic, plastics of all sorts. I have the luxury of a couple co2 lasers, but a few circular saws as well. The saws are all running fine tooth carbide speciality blades and are the go-to method for straight line cuts because of speed. The type of acrylic is very important, cast being the best for cutting of any method. Extruded being the worst, as it is "gummy" and tends to melt rather than cut. Visually they are tough to identify, being pretty much identical until hit with a blade or beam. Dremel used to make a small, affordable table saw with a 4" diameter blade, and are sometimes seen on places like craigslist. Equipped with a fine tooth carbide blade the cut up to 1/8" think acrylic very well. If you can create a vector file of what you need, a local sign shop with a small laser might be willing to cut it for you at a decent price. Lasers are also popular in awards shops as well, or local maker groups.

author: LapTop006
author_rank: Unknown
timestamp: February 13, 2019, 01:57:23 pm
content: Quote from: cdev on November 08, 2018, 06:51:08 pmLast time I looked deeply into their stuff the bigger things (the saw mentioned earlier, their drill press, a few others) were reasonably priced, even in Australia, although their smaller hand tools were expensive compared to alternatives.The ones I've used have also been solidly made, and in a shared workshop have stood up better than many other tools.

author: cdev
author_rank: Super Contributor
timestamp: February 14, 2019, 05:44:19 am
content: I got the little knife and Ive been fooling around with it and it works pretty well! I should have some basic acrylic device cases soon!

author: overlordManny
author_rank: Newbie
timestamp: February 14, 2019, 04:13:25 pm
content: Also don't forget that the cut edges can be sanded and flame polished if you want it perfectly clear. It puts off some nasty fumes, but it sure looks great. Use a respirator or be in a well ventilated area.https://www.youtube.com/watch?list=PLfjdwZlON-2W2cdJAbv0zv_juwcX94K7t&time_continue=66&v=Mmd56UMHDK0

author: james_s
author_rank: Super Contributor
timestamp: February 15, 2019, 01:22:29 am
content: For straight lines I usually score it with a utility knife and straight edge. For curves I find someone with a bandsaw or scroll saw. A handheld jigsaw with a fine tooth blade works too as long as it's variable speed so you don't melt the plastic.

author: basinstreetdesign
author_rank: Frequent Contributor
timestamp: February 15, 2019, 07:12:27 am
content: Quote from: 6PTsocket on November 08, 2018, 09:08:35 pmYeah, I have done it this way and it works just fine as long as the score is at least a mm or two deep and the material is held in a vise at the score line and then hit/bent with good fast force along the line.As for drilling it, a pillar drill works fine with ordinary bits. It needs to be at the fastest speed the drill can deliver, though, and take it slowly.It can be bent with a home-made jig made with small hinges and two pieces of plywood and a scavanged heater from a toaster-oven on a variac. You have to play with the power and time a bit but will bend straight away on the hinge line after a short warm-up time. Too hot and you get bubbles along the bend. Too cold and it wont bend at all.

author: KL27x
author_rank: Super Contributor
timestamp: February 16, 2019, 01:10:40 am
content: ^He basically made his own cutter. Cutting a notch into the back of the blade make a little single saw tooth. I was wondering how he got that result (and that sound) with a blade. Had to rewind it to see what he was doing.I used to have one of those carbide tipped knives for scoring and snapping carpet backer board. Bought it on the rec of some forum members for FR-4 and the like. I eventually lost it, and I just made my own out of an old jig saw blade stuck into a wood handle (like a tiny scythe, stuck in from the side at an angle). It dulls, but I am pretty good at sharpening things. It's essentially the same as a tip of a knife blade, except you use it backwards with the flat "spine of the knife" going into the cut and the sharp edge trailing behind. You just have to get the right angle. A bit of positive rake so it doesn't dig in and jam. Gonna post a pic, because it started out super crude and I eventually figured out what to remove from the handle to make it more efficient in size and shape and ergos.Soda bottle cap for size reference()The single bevel makes it "right handed," to score right against a straight edge.In addition to scoring, I find it makes a great marking knife for metals and wood. For wood, you just gotta go light on the first pass or two. After you get through the surface fibers, you can make your mark/score as deep as you want, unlike with a regular marking knife.I found this so handy, I eventually made an ambidextrous version, years later.(https://i.imgur.com/aIuyZrd.jpg?1)Heh, the original is a little burnt and has some melted parts on the blade, because I used it as a hold down while welding.

author: Richard Crowley
author_rank: Super Contributor
timestamp: February 16, 2019, 01:24:02 am
content: Quote from: KL27x on February 16, 2019, 01:10:40 amNo, the blade comes with that notch. But only the first of the snap-off blade segments have this notch.That is why he advises to never snap off the first segment if you want to use it for scoring acrylic.The reason it works is because it cuts a square-shape notch in the plastic. While the "regular" sharp end only "plows" a small V-groove. In this way, it is similar to the purpose-made acrylic scoring tools.

author: KL27x
author_rank: Super Contributor
timestamp: February 16, 2019, 01:41:20 am
content: That's pretty neat. If you get the angle right, the front of the cutout will act like the mouth/sole of a plane, so you can potentially use a more aggressive rake angle. Even if you snap the tip off, you can make a new one with a dremel and a cutoff disc in a hot minute.After learning how to sharpen things, I have pretty much stopped using disposable box cutters and exacto knives, myself.QuoteYeah, I see that. Mine cuts a pointed V groove, but it works because it's like a sawtooth. It removes a curl to clear its own kerf, deeper on each pass. The flat face is the widest part, so it cuts from the edges of its silhouette and has proper clearance, like a saw tooth. I copied how the carpet scoring knife tip works. The "regular sharp end" of any knife would also work if you turned it backwards (assuming is has a flat spine with crisp edges all the way to the very point), but the angle from the handle would be ergonomically wrong, and that would be a good way to screw up your line, scratch up your plexiglass, and stab yourself.

author: metrologist
author_rank: Super Contributor
timestamp: February 16, 2019, 02:26:00 am
content: I've used the score and snap technique on many things. I also use a small band saw and a milling machine on acrylic. It's OK, just a little brittle.A tip, if you are using a mill and cutting to an edge, you can chamfer the edge before cutting to avoid chipping.

author: billbyrd1945
author_rank: Regular Contributor
timestamp: February 16, 2019, 03:16:35 am
content: I used to make acrylic boxes for hospitals. It took me a couple of years to learn how to get what you're after. I used 1/4" stuff. I used a $200 made-for-acrylic blade on my table saw for rough cuts. But you can use a straight edge and an acrylic scoring tool (Home Depot), and then snap it in two over the edge of a flat surface. Then, I used a router table with a 1/4" carbide spiral up-cut bit to get smooth edges suitable for solvent welding or merely for appearance. Set your fence so that the piece will just fit between it and the bit and do a dry run pushing into the rotation of the bit. Then move the fence ever so slightly toward the bit to get a clean, smooth cut. I would then break the sharp edges with the scoring tool or a file or a bit of sandpaper, whatever. I usually went for the highest speed on the router, but got pretty good results on just about any speed. Bits are not expensive. I usually go them at MCLS.