advice on cutting tools

I generally use a bandsaw, but one can also scribe a line on the stuff and bend at the line. It should break reasonably clean. Cutting thicker plastic, particularly clear acrylics, is quite a bit like cutting glass. But then, I have never been very good on cutting glass, so I don't use that method very often.

Length of cut is important. If the sheet is not too big you can cut it with a back saw.

I have used a table saw for bigger pieces but that is really tricky. You must feed it at just the right speed to keep from burning. If it burns it may stick and break the sheet.

At least with a bandsaw burning/sticking does not usually break the sheet, but I don't get as straight an edge, either.

A shear, of the type used for cutting sheets of metal, is also a possibility. I believe small, hobbyist size versions are available. Check Micro Mark for one possible source.

That's awfully heavy plastic for modeling but you didn't indicate what scale or how big the structures are going to be.

Most modelers don't use anything thicker than 1/8" (0.125" or 3.5mm) plastic as a base for structures. It's easier to layer other sizes of plastic onto them to create depth and architectural features.

Cookie Sewell

Try a hacksaw.

I use a wet tile saw, cuts very smooth, but has a wide kerf.

Cutting 1/8" and thicker material is best handled with a table saw and a miter saw. Use a blade designed for plastic laminates or plastic cutting. Most acrylic fabricators use a table saw with a plastic blade for cutting. Thin kerf blades , about 3/64th's, are available from any legitimate cabinetmaker supply shop. Good luck Mike M

You can do a "poor man's" version of a plastic blade by taking a STEEL plywood blade, and mounting it backwards. It turns out the back side of the blade is just about the right cutting angle for plastic.

Do not, under any circumstances, use carbide blades because you'll pull the teeth off. Those teeth go flying in whichever direction at high velocity. Extracting one from your body will require the assistance of a surgeon, preferably assisted by an anesthesiologist.

Cheers, Dave Ambrose

serveyerself wrote the following:

The installer of my vinyl siding used a sliding miter saw with a cheap fine toothed blade mounted backwards. When I built my pool house afterwards, I did the same.

Sorry Dave, wrong answer. Never ever run a carbide blade backwards. The trick of cutting with a steel plywood blade reversed is used for cutting thin sheet metal steel in a pinch. Really dulls the bald quickly. I've used carbide blades for 35 years. Plastic will not pull a tooth off a quality made blade. If you have teeth flying off your carbide blades, its time to buy a better quality blade. If you use the wrong blade what will happen is the teeth will get too hot and melt the plastic while cutting. leaving a very messy edge. That is why I specifically said, you must use a blade made to cut either plastic laminates or plastic. In a pinch a good quality 10" ATB(alternate tooth bevel),negative rake,6o tooth blade will work just fine. I have cut wood, plastic laminates, acrylics as well as non-ferrous metals( they will nick a tooth occasionally) with these blade. I can not remember ever having had a tooth weld break loose. I usually break teeth when dropping a blade on concrete. Alway use a replacement throat plate the has no space between the blade and the plate. This will prevent the blade from pulling the plastic down into the opening. I would also recommend a feather board to help hold the sheet firmly to the table making it easier to feed the piece through the saw. Mike M

If anyone is googling, the term for this throat plate is 'zero clearance'. Usually made by raising the blade into a blank plate - normally wooden, but sometimes 'plastic'. Make sure the plate is properly secured when you do this.

LD

There's several different ways to get the stuff cut. Scribe a line and walk up to it with a saw, keep on scribing a line until you break through or can bend the plastic and break it, shears work with some plastics and jobs One thing to note is that it is wise to cut away from the desired edge by a little bit and wak to the edge with a file or sandpaper as that will produce a much better edge on the plastic as well as more guaranteeing that the job isn't damaged.

-- Bob May

rmay at nethere.com http: slash /nav.to slash bobmay http: slash /bobmay dot astronomy.net

I'd be working out a cutting list and talking to my local laser cutter. Most of those machines can handle mild steel up to 16mm thick, and its accurate, repeatable and has very little wastage.

RobG (the Aussie one)