I am trying to scratch build some HO plastic scale structures and currently kit bashing and molding some parts. Some of these parts will need to be cut. These plastic parts vary in thickness from about 1/8 of an inch.
Can someone please give me advice on a good cutting tool that can cut a straight line, perhaps for 4-8 inches? It is improtant for my project to keep the cuts straight and this has been a problem for me.
Thanks for the advice and comment in advance.
simplest would be a (metal) ruler… much like the scale ruler offered by Micromark. Just take it slow and make multple light passes til you get a decent score line that the blade will follow before putting more pressure on the blade (it’ll help keep it from “walking”). Depending on the thickness of the stock, you might also be able to use the score & snap method.
You can try the NWSL Chopper… but I’m not sure if it can handle cuts that long…
The Chopper uses a razor type blade and is far too short this purpose.
A straight edge of metal is a good start. Any good brand of hobby knife should make a quality cut but the MOST important thing, and the thing that we all tend to skimp on, is that if it is an important cut use an absolutely fresh blade. It is the slightly dull blade (which may be fairly “new” and will feel quite sharp to the finger tip) which wanders away from the straight edge.
A bit of masking tape holding both the plastic and the straight edge might aid in getting a clean cut. A firm support for the plastic is probably even better.
remember you do not have to cut through the plastic - if the scoring is deep enough the parts will simply snap apart. With care you can get a deep enough cut on the first pass
Dave Nelson
Forget the NWSL Chopper – it uses a single edged razor blade that can cut only very thin material that is no wider than the length of the blade.
They do have another product called “The Duplicutter II” that is made for larger material. Rather pricey unless you have lots of cuts to make.
As others have noted, a metal straightedge is essential for straight cuts, as is a sharp blade. For long cuts, even up to 8’, I prefer to use a utility knife and a fairly thick straightedge. This makes it easier to keep the blade perpendicular to the surface of the material being cut. These blades last as long as X-Acto blades, but are much cheaper - I got a pack of 100 for not much more than the cost of a dozen X-Acto blades.
Most cuts in sheet material do not need to go right through - make the first pass fairly lightly to establish a path for the blade, then a couple more passes with more pressure - the sheet should then snap apart neatly, with very little clean-up required. I find that dragging the upper face of the cut edge over some medium grit sandpaper will remove the ridge formed by the plastic displaced by the passage of the blade.
Most strip material can be cut with any sharp blade, and for cutting multiple parts to the same length, the NWSL “Chopper” is a useful tool. For larger projects, look for “Plastic Suppliers” in the Yellow Pages - 4’x8’ sheets of styrene are available in many thicknesses, for a fraction of what we pay in the hobby shop for smaller amounts. I like .060" for big structures, as it needs less bracing, and where bracing is required, it can be 1/2" strips cut from the same sheet, then cemented, on edge, to the interior walls or roof. I prefer lacquer thinner as a cement - it works as well for styrene as any commercial product and is a lot cheaper.
A station built from .060" sheet:
More .060" sheet combined with some Walthers kits:
Wayne
I pretty much agree with Doc. I’d like to add that have glued 220 sandpaper to the back of my straightedge to keep it frrom slipping. I too like to use a utility knife as the points on an X-acto will break off usually within the first inch of cut unless you are very,very light touch and have all day to make a cut. I ususally just scrape the burr left from the cut with the utility knife. Circles are another story. Usually just makae a whole bunch of straight cuts around the out side till I got a rough circle,then sand down to the circumference. BILL
I bought my 16" stainless steel ruler at Michael’s. It comes with the cork backing to keep it from slipping. I also use the utility knives that have the snap-off blades. At times, I am able to find them, with extra blades, for as little as 99 cents. AND they come with extra blades.
As everyone has already stated, a metal straightedge is mandatory. However, I disagree about using a sharp knife for the first cuts. The #11 blade, and others, is too flexible and the sharp point can wander off your line. I like to start off with a sharp scribe. You can buy them, but I use an old three-sided needle I stole out of my mom’s sewing basket 35 years ago. I just chucked it into an old X-acto pin vise. I measure for the cuts, and mark the start and end points with the needle (more accurate than a knife). I then stick the tip back in the first hole and snug the straightedge up against it. I pivot the straightedge close to the second hole, move the needle to it, and snug up again. Recheck the first hole, and when you are sure they are lined up properly, drag the needle towards you, always keeping it against the straightedge. You should remove a thin spiral of plastic. Repeat several times. Now depending on the thickness of the plastic, that may be enough to snap a clean line. If the plastic is thick, you may want to finish with a razor saw (I love the Zona line); tilt the saw back and use the last few teeth on the blade, again drawing it towards you. Now I know some of you knife-purists out there are jumping up and down right about this time, but this technique has been described in every model magazine for years. If you do want to use a knife, use one with a broken tip and turn it over, using the back of the blade.
Don