ENTREPRENEURIAL OPPORTUNITIES?

MIGHT THE COVID-GENERATED CHANGE IN ATTITUDES TOWARDS WORKING AT HOME TRIGGER AN INNOVATIVE TYPE OF HOME-BASED INDUSTRY?

In these days of Covid and lockdowns, the rise in the number of those working from home has been considerable, to the point at which some businesses are embracing it as a new way of operating.

When we think of home offices, we generally imagine a spare bedroom fitted out for the purpose, because we tend to think of it as a computer workstation, desk-bound office — a scaled-down version of our preCovid situation; the one tied to the commute, the bought food and coffees, and the increasingly hard to find car parking spaces.

But what about the garage or shed — what degree of opportunity lies there? This is not an unusual workplace for some — small wooden items cut out with a bandsaw, single items turned on lathes, sophisticated models or patterns and moulds for a production run elsewhere, but each one created by hand as one-offs.

The possibility of taking on an order for 100 and competing with a larger commercial entity has never been a real option without capital and expensive machinery, along with the planning and production lines that accompany such an undertaking. Not to mention the compliance and resource consent issues that it would raise — or that your neighbour would raise.

What if that were all to change — in the manner of the loom in the home that was taken for granted before the industrial revolution? Might there be a 21st century equivalent? Now, the loom was a one-off bespoke production tool — and a manufacturing operation in the middle of the lounge might cause other problems, particularly on the home front — but the principle is the same. Into this space comes the 3D printer, the CNC router, and potentially, the laser cutter. In this article we’re going to concentrate on the CNC router, but it is clear that there is huge opportunity here for those with the entrepreneurial spirit.

Some parallels

It’s easy to see the parallels between 3D printing, CNC routing, and laser cutting, as they all work from a typical CAD x, y, z axis structure, recognise the same .dxf file to begin with, use the same programming code — G-Code

— and accept the same file formats: STereoLithography File (.stl).

Each has helped revolutionise precision-based manufacture at bespoke as well as economic levels of performance. A shed that has them all is as well equipped as larger manufacturing plants were not that many years ago. In fact, a shed that has them all has the potential to become a hub of innovation, with design and testing processes that were once the domain only of companies with deep pockets that could afford the iterative process of product development. I find it fascinating that it is now possible to focus on any item — no matter how insignificant it might seem — and improve on it as the moment sees fit.

Economy of scale

Take the humble cheese slicer, for example. I picked it because these are always breaking. As a designer I had noticed this and had been thinking about it for a while, so when the opportunity to write about the CNC router and the fact that a one-off is effectively as economic to produce as a run of 100 might be, I was in. I say ‘effectively’, as in a commercial situation there will be file download and set-up fees that distort this. However, these are a one-off, and, after they are sorted, they remain on the server waiting to be reused. Economy of scale no longer has the same impact as it really is just as cheap to produce one as it is to produce one 100. The upshot of this, for those who are interested, is that the bespoke is now potentially a commercially viable business model.

The process

Des Thomson’s CNC router kitset, which we are showcasing in this article, was bought from V1 Engineering, while the router is a small hand-held Makita offering. What is particularly interesting is that some of the parts required to set it up were made by the device itself while others were printed using 3D printers, as we shall see.

The kit sits on a tall table on castors, about a metre square, so it is easily stored or repositioned as required. A shelf just above the castors holds the dust extraction cyclone and bucket, making it completely self-contained. A small console accepts an SD card in exactly the same way as a 3D printer does. The only other piece of hardware is an older laptop on which Des has EstlCam, a free G-Code generator, which he uses to prepare the SD card for the console. The item to be produced — in this case, my cheese slicer — had previously been drawn up in iCADMac, a Mac-based alternative to AutoCADd. I exported it as a .dxf file, and, as the file size at 23KB is almost insignificant, I downloaded it onto a USB drive I keep on my key ring and went to see Des. It would have been just as easy to email it, but this is what we did.

Let’s try it out

Once I arrived, Des set about converting my file to the format the CNC router required. This was a very interesting process, as the final result not only showed the software model the router required, but it also actually emulated the cutting process as it would occur, live. This might be old hat to some, but it was new to me, and I was fascinated by it. The process involved a range of software ‘tools’ to determine the cut variables — depth of cut, width, curve radii, and the like. The path direction is always the same — a point to remember when selecting soft wood, for example. We’ll return to this point later on. The depth needs to be considered carefully, because this is where problems are likely to occur.

There are a number of rules around this aspect:

• The depth of the cut should be no more than 50 per cent of the diameter of the cutter, although this rule of thumb is also subject to the hardness of the material

— the harder the material the shallower the cut is a good maxim to remember.

• The depth needs to allow for a cut past the thickness of the material in order to achieve a clean separation. This is done by having a spoil board — in this case a piece of 4mm-deep MDF.