Making Accurate Stryrene Cuts

[Noah Lane]

I am attempting to cut long(ish) styrene strips to place them in between my yard tracks. I want the tracks look like they're set in a concrete pad.

The small yard will serve a slightly bashed Long Valley Lumber kit by N-Scale Architect. I've tried using a straight edge (for the long straight sections) with a brand new blade on X-acto and hobby knives, but the blades always seem to run. The curved sections on the small #4 turnouts are more manageable with simple sanding.

What's the trick here? Do I need a Chopper or something?

Also, any good sections to make the styrene look like concrete?


Here is the one section I did, which took my quite a while and isn't perfect


Thanks
Noah

[dougnelson]

Noah:

For straight sections, use a steel straight edge and the trick with sharp #11 blades is to cut with several strokes and start with light pressure.  This will score the styrene and create a "track" for the blade to follow.  Continue with several strokes until you have cut through the styrene.

Doug.

[robert3985]

Also, place the straightedge so it covers the portion of the Styrene you don't want to mess up, and if your blade wanders, you can always sand the crooked part straight.  On critical parts, I tape both the straight edge and the Styrene down with plenty of masking tape.  Truth is, sometimes a #11 blade is a little "pointy" for long, precise cuts.  You might want to try a less pointy blade that naturally supports itself better.

You're going to find that when you break the score, the edge isn't perfect so sanding it will be necessary or you can use a sharp blade held at a right angle to the burr to scrape the surface flat at the break.

Although precise breaks are nice, I will sometimes make the part just a bit oversized and sand it to final size, checking it often to make sure you don't overdo it 'cause Styrene is soft and goes away quickly when sanding.

[DKS]

Since this is a concrete surface, it will naturally have joints. You will find it much easier to make shorter cuts more accurately, then simply piece the strips together in place. Make the pieces very slightly oversize and then lightly sand the edges down until the pieces fit.

The blade won't run if you use the score and snap method. The trick is to hold the blade backwards (don't press your finger on it!) and score the styrene with 5-6 firm strokes. Then snap the sheet by bending it over the edge of a table.

Use sandpaper to give it texture. Usually concrete has something of a "grain" so make the final sanding in one direction. Use the scoring method (gently) to add more expansion joints. I like to spray the styrene with Testors Light Aircraft Grey as a good concrete starting color. Apply some ground pastel lightly in areas to weather it.

[gary60s]

To keep your straightedge from slipping on the styrene, glue some thin sandpaper on the bottom edge. Also a SERB (Single Edge Razor Blade) will give you a cleaner cut than an exacto.

This thread shows pics of modified straightedge, and how to make a cheap SERB holder:
https://www.therailwire.net/forum/index.php?topic=30539.msg336464#msg336464

Others are correct with single pass with straightedge, then other passes in groove without straightedge. Scoring and snapping can be better than cutting all the way through.

[Catt]

The only change I would make to David's advise is to make the first couple of passes with light pressure,once you have a scoreline deep enough to keep the blade in place then increase the pressure.Not all styrene cuts the same,some of it will snap with a light scoring and some you will have to cut half way through it.

Watch the tip, of the blade. Styrene will dull it fast, if that sharp point is gone get a fresh blade for your scoring.The blade is still useful but if used for scoring it will try to wander away from where you want it to be (voice of experience here).

[Noah Lane]

Okay, awesome. The score-and-snap method sounds very doable.

I think I can take away some constructive each knowledge from each of your suggestions.



Would you guys approach the narrow strips that will sit between rails in the same manner?

[DKS]

Would you guys approach the narrow strips that will sit between rails in the same manner?

Yes. Just be mindful of the flange clearance.

[Scott Lupia]

An old Architecture School trick is to run some masking tape along the underside of your straightedge.  It serves the same purpose as gluing sandpaper but won't damage the surfaces it is resting on.  Also, you can just peel it off.  Electrical tape works as well but us Architecture kids never had that stuff on us. 

scott lupia

[DKS]

One other thought--for long straight cuts, I often use a big old (guillotine-type) paper cutter. Once the styrene sheet is aligned, I tape it down and let 'er rip. If you have access to one, it's a useful tool.

[wm3798]

I got an inexpensive paper cutter from Staples.  Worked like a champ on millions of projects with nice square, accurate cuts.

Lee

[chicken45]

I still struggle with square cuts on my Chopper.

[TiVoPrince]

Place
kraft (or butcher) paper over the scene with a few pins (reinforce with mesh packing tape) to hold it firmly in place.  Rub a crayon lightly over the rails to create a perfect image of the ACTUAL layout of rails and such.  Use rubber cement or double sided tape to adhere paper to styrene and cut to the crayon lines.  A secondary line drawn between the rails will allow you to account for flangeways. 

Cut with blades or scissors as you wish but this gives an exact fit to what you built, not what you hoped to build.  We all try to lay laser straight track but most of us fall short...

[DKS]

I still struggle with square cuts on my Chopper.

The Chopper is made to cut strip stock. It's not designed to cut sheet material.

[TerryN@StDave.org]

Since you are using Unitrack, there are a couple of other solutions to this problem.  Kato has just introduced track set in slabs of concrete (20-014).  It may not be exactly the look you are shooting for, but they created it to be just that.  I got some to use as a station track, and it serves that purpose very well.  And if you are looking for track buried in pavement, you might look at their tram track (40-010) or continue with the Styrene cutting techniques.

Terry N
T-Kits.com