The World of Autojumbles at your FIngertips

how to... draw on your skills

Even if you’ve no intention of making anything in your own workshop it is still nice to be able to produce a sketch to show someone else what you want them to make for you. Obviously the better the sketch or drawing you produce then the easier it will be for anyone trying to interpret it, but there’s no need to spend thousands on all sorts of specialist kit as the bare basics will suffice.

The reason for this little artistic interlude came about when I was attempting to make some Bultaco style mudguard stays for my trials BSA B40. It would have been possible to get a set of replica stays that would have been close but which would require modifying – I did offer up the original ones from my Bultaco to see what they would be like – and by the time they’d been modified it would have been just as quick to make them from scratch. So, that’s what happened.

Saving time later

It is possible to simply hold bits of metal up against the fork legs and patiently hacksaw, file and sand them until they’re the right shape, but that is a long process...

I know, I’ve done it. It’s much better though to draw something, make all your adjustments on paper, then cut the final bits in metal – it saves a lot of time.

In the past I’ve had to make all sorts of things, both for motorcycles and for houses. Sketches have ranged from fully proportioned drawings in a recognised scale, when making things like doors, windows and staircases, to back-of-a-screw-box scribbles for other things. The point being, there is no real need to be a trained draughtsperson to come up with something that is going to be useful. The pictures accompanying this piece will confirm that since none of them are particularly artistic. You can see from the two sketches I did to plan out my blast cleaning cabinet some time ago – they are all crossings out, scribbles and notes.

Changing ideas

Given the ease with which it is possible to alter a drawing, this is the place to get it wrong. It’s no great cost to redo, or scrap a bit of paper, or even paint over something. I think the blast cabinet sketches were version six or seven in the series and theyincluded all my changes of ideas and sizes of materials and the physical room I had available in the workshop.

Okay, what do you need to be able to produce a useful sketch? Something to draw on for a start. This can be a sheet of paper, a bit of cardboard from a brake shoe box or, as in this particular case, an old wardrobe door. This was chosen for two reasons a) it was big enough to draw out full size what I was going to make and b) it was coated in flat white paint.

Next you’ll want a pencil. If it’s a hard one – 2H or so – then that’s better but don’t panic if it’s not, just have a sharpener handy. Next, some form of straight edge will be useful. I’ve still got a plastic ‘T’ square from my apprenticeship days, though any straight edge will do. Some way of marking a circle will be useful too, especially if you’re positioning a mudguard like I was. While a pair of compasses will be the first thing that springs to mind when circles need to be drawn, an easier method for me was to drop the wheel onto the  door I was using, fix the centre of the spindle in place, put the pencil on the tyre and spin the wheel.

Working drawing

While I was at it, I dropped the fork leg on the board and this showed me where the stays should go too. After that it was a simple job to virtually join the dots and have a working drawing to start bending and cutting metal to. The task was made slightly more complicated by my need to make stays that would accept a pre-drilled Bultaco mudguard. Why? It means that if I’m off to a multi-day event, I can unbolt the mudguard from my Bultaco and have a spare all ready to go in case of emergencies.