Wolgan Valley and NSWGR

Tip sheet for working with Styrene

Important points:

The first rule when working with smooth styrene sheet is LIGHT IS BEST.

The first cut is likened to a record player arm, EXTREEEEEEMELY LIGHT.

With each consecutive cut the pressure can be slightly increased. The best guide is always use a sharp blade. I prefer scalpels with a fine 25 or 25A blade. Thick hobby knives put too much stress into the sides of the cut creating all manner of distortion.

0.5mm styrene takes 4 cuts to get through, whereas 1mm styrene takes 9 cuts to get through. If you get through quicker you are pressing too hard and run the risk of breaking your model or worse, slipping and having to live with a repair. Too much pressure distorts the cutting blade which results in loss of control and crooked cuts.

When cutting narrow strips, too much pressure will fill the styrene with uneven stress and will curl or bow the part. Practice on scrap to experience what can happen. With light pressure you should be able to cut very fine strips with minimal curving.

Never apply so much pressure that it is difficult to hold. This is just plain dangerous.

When cutting very small, fine pieces, never apply more pressure than it would take to break the part. Obviously. When sticking to this rule you can cut out the finest of pieces with out breakage.

Patience is all it takes, pride is in the “puddin”, the “fun” is in the journey.

When cutting fine parts, eg. window sashes, etc., cut out the inside areas first, ie. where the glass goes, then cut the sash away from the backing sheet. I mostly use a small steel straight edge for this final step. When cutting out internal areas, cut from both ends of the line, ie, start the cut from one end of the line digging the point in at the corner then cut to just past the center of the line, then turn the job around 180o and cut from the other end

With practice, you don’t necessarily need to use a straight edge for the majority of the cutting, just start with very light pressure and the groove will guide the blade. The blade will not run out unless undue pressure is applied.

Cut styrene on a cutting mat. The green ones from the hobby shop or “$2” shop are best. They don’t fall into a hundred bits after you have made your model.

Solvent welding:

Vent the area. Solvent fumes CAN get you, especially chloroform. The more dangerous chemicals (cancer causing) will get you if you breathe them in over extended periods. The time it takes you to build a model is all the time it needs.

There are many solvents available to use with styrene. Many are unfortunately cancer causing. TETRA (see Simply Glues on internet or shows) seems to be ok, I use TETRA and/or chloroform. MEK or Weld-On-3 works, as do many others.

Apply solvent to the model with a good quality hair brush, sable to great if you can afford it, because it goes to an extremely fine point for accurate placement of the solvent. Synthetic brushes may dissolve in the solvent.

Solvent runs well into joints by capillary action, but, if you are supporting a job, with fingers or jig, remember that capillary action works everywhere, so add the solvent cautiously and wisely or you will deface you model where you are holding it in the jig or fingers.

Should you snap any part, DON”T PANIC. Solvent welding technique is perfect for fixing styrene. Simply hold the damaged part in place and solvent weld as normal. I have made many a slip and cut too far, but no one can find it on my models.

Always assemble on a sheet of glass. Its nice and flat and your model will set straight. It’s also very easy to clean, just give it a scrap with an old blade and even superglue will come off. I also place the model instruction sheets under the glass for quick reference and this also protects the sheet.

If you need to clamp parts together, eg inside and outside faces of walls or carriage sides, it is very good to clamp them between two pieces of glass. I have a range of sizesleft over from old photoframes.

Jigs and clamps are useful. A simple jig is various sizes of square cut wood or (even better) steel blocks. They can be arranged in all manner of configurations to support your model parts during assembly. Caution – capillary action!!