Given that a hot wire cutter is one of the more expensive additions to a terrain makers tool kit, and that they are sometimes hard to obtain, it's hardly surprising that many people consider making their own. If you are thinking of doing this we strongly suggest that you check out our general information about hot wire cutters, our reviews of commercially available products, and out international list of sources. Given the difficulty and cost of obtaining parts, and the work involved in making you're own, you might conclude that a hot wire cutter is one item that your better to save up for after all. For the benefit of those who remain undeterred, Luke Pillar tells us how he made his own bench type hot wire cutter.
Interestingly Luke settled on the same power source (a 9v 1Amp low voltage power unit) as Gary James did for his hand held hot wire cutter.
Please do not attempt this, or any other project involving electricity unless you are competent and confident to do so. Get some help if necessary. You should also read this document to acquaint yourself with the potential hazard from toxic fumes that can be generated when using a hot wire cutter.
I made my table about 750mm high to give me heaps of space to put a chair (and my knees) under it. All joins are square cut so there's no messy mitre cutting required. Cut the angle into small strips narrow enough to be able to fit inside the AHS as these will be used as brackets. I've made the frame about 100mm smaller than the MDF, so there's a 50mm overhang around the entire table. I should have made the rearward lip larger, as it would have enabled me to fix the wire arm more securely.
Cutting the AHS as required (I'm not going to give you the exact measurements as I've lost them...), I fixed the lengths together using the angle. This took a while as the angle needed to be flush against the AHS and care must be taken. Alternative to making the whole table, it would be far easier to simply get your hands on an old one and hack it as required.
Cutting the timber stud to size, I've made the wire arm up so I can fit about 200mm of foam under the whole contraption. In hindsight, I should have made it a little higher, as cutting thick foam on an angle can be very difficult indeed. The length of the arm reaches in to 390mm from the rear edge of the table. This allows a full foot of foam to be cut (which is the usual size of the scenery tile I make).
The arm is fixed by two huge furniture bolts (about 10 gauge x 3.5 inches that I found in my toolbox) through the aluminium into the bottom horizontal piece of the arm.
The wiring is pretty basic. I've set an adaptor plug on the frame, and then run one wire to the top of the contraption and another to the bottom. On the top, I've put a push button so I can turn the thing on and off without reaching for the power point. I'm really glad I did this - it's worth taking the extra few minutes to hook up some sort of switch to the device.
The wire is simply taped into place using gaffer tape. I used two loop hooks (also called eye-bolts) to attach the nichrome wire to, and over the loop, I've managed to wedge some (heat resistant) plastic tube to stop power drain through the hooks (that is, to stop the loops shorting out through the frame of the table - Gary).
Directly under the top loop hook, I've drilled a hole for the nichrome wire to run through. The bottom hook was then screwed into the crossbrace piece of the aluminium frame so the wire can be attached in the vertical plane. It's important to spend a decent amount of effort into getting the wire as vertical as possible otherwise you'll have problems getting foam to sit flush after you've cut it.
The part of the project that I've had most trouble with is the power source. Currently, I've gone through about 6 different AC/DC adaptors trying to find one that puts out enough power, but doesn't burn out. The best so far is a 9v/1A that I found (another piece of junk I never threw out). This thing was awesome - it would cut through foam like a hot knife through butter. Unfortunately I left it on for too long (about 5 minutes continuously) and it stopped working the other day. I know it's too much power (it shouldn't get that hot) but this thing rocked. For all those electrical types out there, perhaps taking the time to work out the precise input would be of benefit. (Note from Gary - I use 9v 1Amp with a hand held cutter. I'd expect a wire this long, therefore, to get hotter when used on a bench model. I'd suggest a lower rated power supply and/or a thicker wire than the 0.25mm / 33SWG used in the hand model.)
The whole table is a very basic concept. What I've put here shouldn't really present any outrageous ideas, but hopefully it will inspire a few people (with enough space) to put one together. One further item is essential - some sort of full length brace that will act as a straight edge guide. I've got one made of two lengths of pine screwed together (held tight by some clamps), but anything straight would be fine. I apologise for some of the poor quality pictures but hopefully they should convey the essential parts of how the thing goes together.
