hello
i was recently trying to cut a piece of sheet styrene, and im wondering which tool to use. When i used a knife, i kept making different cuts and was ruining the styrene. When i used my motor tool (cutting disc), the disc broke into pieces the moment i touched the sheet.

Which tool should i use?????

Use a metal ruler to get a straight edge. Then lightly track/score the styrene with the knife, several times until you get a nice track to cut it. Then the knife will follow the already made track instead of going stray.

When cutting sheet styrene, slow and steady is the way to do it. Use a steel straightedge and start with light pressure, scoring the plastic. After a couple of passes, as the cut gets deeper, press a bit harder. Be sure you are cutting on a safe surface, not the dining room table. LOL
If you don't have some kind of cutting board, use several sections of the Sunday newspaper. I find the classified/car dealers sections to be the thickest.
After cutting almost through, you can usually bend along the scored line and break the plastic sheet.
If it is light gage sheet, a #11 blade will work. If it is thicker material, you may want to use a razor knife.
HTH

Wrapping some paper masking tape (just a single layer) along one of the edges of the steel rule (opposite edge to the one you are cutting along) will help to prevent the ruler from sliding about on the styrene too. Also you may find a slight 'lip' along the edge of the cut sheet afterwards, quick swipe with a fine file or sandpaper will get rid of that.

I use a pair of "divders" to scratch the first straight"cut"......these are ground down on the inner faceof one leg........ and the outer face of the other leg shaped to a trianguler point........the flat face runs along the edge of the sheet and so the width --- set by the screw ---gives accurate lines cut by the "cutting "leg. For short lines I have a cut-down trianguler rule- (6")and so still have the tips of my fingers :-) :-) ....also have a plastic cutter ---similar to a "tile-cutter" (hook end -shaped to point) that I use for extra thick -or for cutting angles for joining--as in boxes etc. As most of my measuring is done with the dividers .I can scratch the measurements on the sheet as I go-----wipe over with finger and the "grime" will leave the marks ...by majic :-)
aye
BARV
(GOSMG)

Remember you will have a large "step" to get rid of on both pieces------I always cut both sides
aye
BARV
(GOSMG)

Use a sturdy ball point pen the make your lines using a metal ruler. With the ruler in place make several passes with the pen using some increasingly harder pressure on each pass. This will make a channel for the knife to follow. Remember that you don't have to cut completely through if you making strips or single cut pieces. The knife will score it in a couple of passes and you can bend and th plastic will snap along you scribed line. I bought myself a couple of Dupli Cutters from Micro Mark. They work great. http://www.ares-server.com/Ares/Ares.asp?MerchantID=RET01229&Action=Catalog&Type=Product&ID=83113

Anyone out there tried the trick of using the 'back' edge of an X-Acto to 'score' the plastic?

You should end up with a bead of plastic coming off the forward edge of the blade. Something like the strip of metal that comes off a bit when drilling.

Supposedly this will prevent the 'lip,' or raised edge, created on both pieces that you get when using the proper edge of the blade.

Just a thought.

just use and x-acto knife and just go slow. i cut styrene i get all the time from http://www.iplasticsupply.com/ and it works great

I use a steel ruler and a razor knife. You may also want to try a scribing tool. You can find them in your local hardware store.

Yes, in that I've used my x-acto blade tip with the flat edge leading to score lines, using a straight edge for a guide. it works like a panel scriber that a/c builders use. You still will want to scribe lightly with repeated passes, but it doesn't create much of raised edge.

In my opinion #18 X acto blades to cut thin sheets
and for the thickest ones nothing works better than the Tamiya scriber





As Guide I use metallic rulers

cheers

Fav stuff, sheet styrene...

Metal straight-edge is essential, taping (I use a drafting rule with a cork bottom, but taping works well if you don't have the cork...), Exacto #11 (new blades!), lightly-tracing over lines several times for the cut, using the backs of Exacto blades to score, using a NON-GRAINED hard surface (NOT a piece of soft white pine, like I have... LoL!) avoids the grain-tracking by the knife, etc.

For thicker stuff, the razor-saw with a miter-box works really well (for straight cuts).

IF I get a lip on the cut piece, I lay the piece on the board and swipe my Exacto knife across it to shave off the lip cleanly. Sanding with finer grit (400+) along the edge also works nicely.

If the edge is not as straight as I need, I correct the edge by sanding it with fine-grit paper on my flat cutting board. This always needs to be followed by "de-burring" the edge with the Exacto or fine-grit.

Cheers!

Bob

I wrote a wrong number. It was, of course, # 11