RobRossington wrote: ↑Wed Aug 21, 2019 8:37 pm
Well, I can’t say it’s been fun, but we’re getting there! People make styrene look so easy, but I never seem to be able to get this bloody stuff straight and square!
You can't beat practice. Modelling in polystyrene gets easier after the first hundred or so models.....
Below is a basic toolkit for modelmaking with polystyrene sheet, more or less what I've been using for nearly 50 years.....
- Craft knife, X-acto, or equivalent, with a suitable blade. I prefer a #11 straight blade, but a couple of mates swear by the #12 curved blade. I now use a scalpel instead of a craft knife as the blade is sharper and the handle has more precise control, but using scalpels tends to frighten some people. Box cutters and utility knives are OK for cutting boxes, but the blades are too wobbly for precision cutting of polystyrene sheet.
- 150mm and 305mm steel rules.
- 6" engineers square. A 3" square is also nice to have, but not essential.
- 0.3mm Pentel automatic pencil, or equivalent, for marking out.
- 4" warding file with handle.
- Needle files. At minimum a flat, a triangular and a round one.
- Tweezers. I find the fine pointed AA type to work best with small parts. Every now and again I try another shape, but always come back to the AA type.
- Cutting mat and a piece of chipboard or MDF as a work surface.
- Solvent and a fine brush. I use MEK ( Methyl Ethyl Ketone) for sticking bits together and use d-Limonene for laminating large pieces, as it evaporates more slowly. MEK doesn't do brushes a lot of good and it will need replacing fairly frequently, as the point gets a bit dog eared.
- 240 grit sanding block for squaring up edges after cutting. Make your own by fixing the sandpaper to a nice square block of wood with double sided tape.
- Pin vise for drilling holes by hand. Using a powered drill in polystyrene usually ends in disaster as the plastic heats up and grabs the drill bit.
- Small G-clamps. Useful for clamping a ruler to the sheet so it doesn't slip when cutting, especially when cutting narrow strips. Also for clamping parts into assembly jigs, etc.
Like Peter, I wouldn't use superglue for assembling polystyrene parts in a fit. The only time I use superglue with polystyrene is for fixing metal handrails and whitemetal details into drilled holes.
While I use the score and snap method for roughing out parts, it doesn't give a good enough edge to get a good square joint. The edge of parts need to be filed/sanded flat, straight and square, or the joint will change angle as the solvent evaporates out of the joint and the plastic in the joint shrinks.
I personally prefer to use a piercing saw for cutting curves and openings. It requires less cleaning up than the cut and snap technique, which can wander off line on a curved cut. Not everyone gets on with piercing saws though.
I generally mark out first with a fine pencil, but then run a light cut along the line and rub the pencil into the cut. That way the pencil line won't be rubbed off by handling and there is a narrow and highly visible line to work to for filing, sanding etc.
I've made various assembly and sanding jigs over the years, but I also keep a few squared up blocks of wood on the bench that can be clamped into a corner once assembled to keep things square until the joint hardens.
Polystyrene sheet works much like wood, but without the grain to worry about. On very long pieces such as coach sides, I straighten and square up the edges with a small block plane. With a sharp blade and set for a light cut, it gives a nice square straight edge without as much effort as using a file and a sanding block.
I'm a tool junkie and have a lot of tools that might get used once or twice a year on polystyrene, so not really essential........
Regards,
Graeme