Advice and opinion, don’t confuse the two.

Instruments: before, big and busy. After, uncluttered and simple.

Instruments: before, big and busy. After, uncluttered and simple.

There is a big difference between advice and opinion. One serves to guide and promote discourse, and the other invariably confuses things and promotes argument. I learned the difference between the two a long time ago and am constantly reminded of that lesson. When seeking advice we are generally hoping to tap into the accumulated knowledge and experience of others whose judgement we trust. Opinion on the other hand is generally something that follows acting upon advice and is subjective, unless of course, the other person has misconstrued your original query, in which case you get a whole load of one when you wanted the other. When I’m engaged in making stuff I ask for advice, when I need it, from other makers I know, and I might canvas their opinion when I’ve finished what I’m doing, but not before.

New headlight brackets and new front indicator light mounts.

New headlight brackets and new front indicator light mounts.

If I’d followed all of the unsolicited “advice” I’d been given about how my bike should be, then I would have wasted a great deal of money and time on what is essentially a cheap form of transport. Working within an admittedly self imposed tight budget, and with time pressure to match, the solutions that interest me are those which are simple, relatively easy to execute and fit for purpose. It is with this in mind that I approach everything I do on this build and it helps to steer things clear of needless expense and wasted effort. One day I might build something more special but, for now I’ll work with what I’ve got. Sorting out the instrument area and the headlight would have been “better” if I’d totally stripped the bike of all electrics, cable drives and other bits, but that doesn’t clear the deck, it just opens up a whole new avenue of expensive solutions to a new set of problems. Working with what’s there meant splitting the clocks to allow cable drives to flex more freely and shorter light mounts to keep things close in and fairly tidy. The bundle of wiring needed to keep things working would stay, although shortened and repackaged. I’d bought some ‘P’ clips some time ago thinking they’d do for mounting the light on the forks and so put them to use. they work well enough for now though I may make replacements with a tighter fit later on. I drew up some side brackets on some graph paper (brilliant for laying out simple parts to scale) and transferred the design onto some aluminium alloy for cutting out. I made a new speedo mount based on what had been there before, but with a 20 degree offset and modified the mounting that came with the tachometer when I bought it, to bring it closer to the handlebar. All this allowed me to raise the light and split the clocks, and try to keep things as low as possible. By tilting the bars back further I was getting near to where I wanted the front to be. It looks a lot more sparse than before, but I’ll get used to it. And the natty little fly screen has gone.

I was very fond of it, but it had to go. A quick word about making those side brackets. Because I’d drawn them out on graph paper, it was easy to draw them again on alloy sheet, you remember all the numbers. I cut them out using a jigsaw, slowly, with a blade for metals at slow speed. I finished them off with hand files and drilled the holes with a hand drill. It takes time but not as long as you’d think and the result is pretty tidy once they’ve had a rub down with 600 grade wet and dry paper.

Here’s a canny bit of advice given to me by my father just before I started this: when filing soft metals, rub chalk along your files, it stops them from clogging. He was right, it did too. You can’t beat good advice. His opinion? Well, he didn’t have one, he’s waiting until I’ve finished to give me that.

Seize the moment.

Stripped and ready for action.

Stripped and ready for action.

The decision to get cracking on the bike coincided with two pieces of good fortune. First, work called just before I started on it to ask if I’d mind staying at home that week as there wasn’t enough work going through the studio to keep me busy. Regret that I wouldn’t earn any money that week was countered by the prospect of getting a fair crack of the whip on my bike build, so a reasonable result. Then, to my utter surprise, the weather turned unseasonably warm and sunny for about a week, perfect for fettling bits of metal out in the shed and garden. Having wrestled the bike into the back garden, no easy task given a very narrow access alley out back and the need to fit some much reduced width handlebars, the strip down was quick. Originally I’d built it in a way that would enable me to take it apart if I ever needed to and so was grateful for having made that decision. The work plan was front mudguard first, then the clocks and headlight area and finally the rear mudguard. After a quick once over and a clean it was time to get started.

Not bad, considering.

Not bad, considering.

I’d sketched out several solutions for mounting the front guard but, in the end opted for the simplest one which used two straps or hoops connecting the mounting holes on the fork legs with the guard mounted on top. Ok, not that elegant, but essentially all you need and adhering nicely to one of my general philosophies when approaching making anything, which is the KISS principal (Keep It Simple, Stupid). Due to the front forks having a leading axle arrangement, the mounting holes are off-set to the wheel centre so the straps needed to be of different lengths, and so I slotted the holes on the rear one to enable some positional adjustment when finally mounting the guard. Trimming the guard from the longer piece of rolled section I had was relatively easy, the tricky bit is joining it all together. For this you need to find the centreline of the guard, awkward on a thing that curves in two planes. My simple solution was to lie the piece on its side and establish the centreline as a height rather than a width, using a pen taped to an adjustable square. That done, it’s much easier to define the hole positions for your fixing screws or rivets to attach the mounting straps. Nothing worse than drilling holes only to find they’re in the wrong place. With the holes drilled I screwed the whole thing together using some M4 button headed screws and thread lock compound. Doing it this way allowed me to tighten things up just so, and minimise the risk of pulling the surface down onto the straps too much and dishing the top surface. The rolled mudguard blanks came with a polished finish but this is a nightmare to maintain, so the final thing was “brushed” with Scotchbrite before a treatment of anti-corrosion spray. Ok so far. Next up, the clocks and front light area.

Before the making starts.

Strange proportions and some serious wear and tear you can't see.

Strange proportions and some serious wear and tear you can’t see.

In the last post, which was primarily concerned with getting into some making as an antidote to creative imbalance, I mentioned that the project I’d be launching myself into would be a refresh of my already custom built little 250cc motorcycle.

Above are a couple of shots taken not long ago of how it was looking. From this distance and angle there doesn’t seem to be that much wrong with it but upon closer inspection it was really starting to show its age. First modified nearly six years ago, it has since endured a life of quite heavy use as a daily commuter and weekend run about. There were two aspects that I wanted to address in my refresh. Firstly, the finishes that I’d applied all those years ago were starting to look very tired. Numerous scrapes and scratches, injuries sustained from sharing public parking bays with careless scooter users, and general wear and tear had taken their toll on the paint work, and the protective lacquers applied to keep it all shiny had reached the limits of their life. Surface cracking and other problems giving the whole thing a rather worn appearance. Some patina of use is good, some just makes things look a bit sad and unloved. So time for a fresh face.

Secondly, there were some aspects of the proportions of the whole thing which I realised I hadn’t got very right the first time around. As you can see the bike is quite low at the back and high at the front, a product of it being a “Factory Custom” bike in its previous life. I wanted to reduce this height a bit to bring a bit more balance. The rear fender was causing me some worry too. I’d made it longer at the outset for practical reasons more than anything, to keep the road dirt off everything, but have come to see it as way too long, the overhang above the rear wheel being too far which seems to exaggerate the odd proportions even more so.

So the plan was to create two new fenders, or mudguards, see what I could do about the height of the front and give it a fresh coat of paint. Thinking it through it seemed like better sense to keep the guards in bare metal, very a la mode these days but, no more worrying about precious paint finishes on bits that get very dirty. I’d purchased two new rolled sections just for this purpose some time ago at a local autojumble so saw this as a quick fix solution that I could do at home.

Dealing with the front end would be a bit more tricky. The instrument bracket I’d made and its effect on the headlight position, together with the fly screen all contribute to a visual height at the front which seems at odds with the rest of the bike. Changing all this and giving it all a bit more breathing space should help, and mucking around with bar positions and suchlike will help too. The forks are pushed up into the yokes as far as they will go, so without drastic fork shortening there’s not much I can do beyond small changes. Some have suggested the more severe approach of having the frame modified but that’s way beyond the brief and, after all, this is a daily workhorse bike not a show pony aiming for total perfection. Not to mention the fact that major engineering of that magnitude costs a good deal of hard earned cash, probably more than the bike is worth.

The final piece in the puzzle will be the new paint scheme. The bike is mainly black and I’ll keep it that way. I want something subtle, but different enough to make it individual. With only the tank and side panels to do it needs to be quite simple. I’d like to have an element of hand painted brush work in there as well as a tiny splash of colour. I’m yet to settle on a final idea though I’m leaning heavily towards something slightly more decorative that a big white stripe. I’m going to keep in under my hat for now, until it’s resolved, as I’ve told a couple of friends it will be a secret until I’ve finished it. Don’t want to let the cat out of the bag yet.

Creative imbalance and making the most of what you’ve got.

Small, but with lots of potential.

Small, but with lots of potential.

It is the only word I’ve managed to come up with in trying to describe what’s been going on of late, imbalance. I’ve got a fair idea about where it’s come from and it has taken me a while to get to grips with it.

Rather than castigate myself for allowing it to happen, it has been much easier to recognise it for what it is and deal with it through action and a little reasoning. This imbalance stems from a shift in my working life over the last few months, and hence my creative output, which I’d not accounted for. Although my role is only part time, it has involved a lot of idea generation and thus a massive amount of drawing and sketching. Big projects, which require a lot of this kind of thing in their early stages, need sustained creative input and masses of ideas. It’s exhausting, creatively and physically. Where I went wrong is not remembering this to be the case and failing to keep any creative energy in reserve for my own stuff once I returned home. So it’s been difficult to draw, but more to the point, it’s been hard to generate ideas.

Shed_2

I’m showing you a couple of pictures of my garden shed, here in my back yard, as it has proved to be the answer to coping with this imbalance. Rather than spend any more time staring at blank sheets of paper the solution lay in getting out there and making something, turning raw materials into something else, using some tools and getting my hands dirty.

 

There had been a plan in the back of my mind for a while to refresh the little 250cc motorcycle that I’d modified some years ago when I started this blog. Over the years, as the miles have racked up, it has suffered the usual knocks and scrapes that these things are victim to, and overall the finish was starting to look very tired. I wanted to give it a freshen up, and make some changes to the overall design that I’d not got right first time around. So what to do for a making project was all ready and waiting, I just had to start. Before now I have relied on using workshop space owned by other people, this time around I didn’t have that option so my little shed was going to need to be the work space that I could use. As you can see it’s a small building with very limited floor area, but it does have an electricity supply, a big light on the rafters  and a work bench across one end. It houses all of my various tools, materials and other useful stuff accumulated over years of working as a prototype builder and modelmaker. Being of a sturdy design and construction it allows all manner of things to be hung from the walls, freeing up floor area and permitting at least a modicum of organisation. I don’t own any large machine tools, I’d need a bigger shed if I did, so most of the work would be done with hand and power tools with my trusty old Black and Decker Workmate acting as a secondary work bench. The only thing I can’t, and likely won’t do in there is spray paint, that will have to happen elsewhere. The shed was here in the garden when we moved into the house and I’ve always wanted to use it as a making space. now was my chance to put that thought into practice.

It just about fits in.

It just about fits in.

The third shot shows the bike pretty much in the shed. I didn’t need it completely inside, just enough to get some soldering done on the electrical loom, but it meant that I could work on it in there if the weather took a turn for the worse. By being methodical and tidying up as I went it was utterly surprising what I managed to do in this small space. Most of us work in some kind of organised chaos. Some cope well the more chaotic things are, others less, and over the years my natural inclination has veered toward the organised rather than the chaotic and this is a boon when working in a confined space. Having everything to hand helps too but, the order one maintains around oneself really is reflected in how one deals mentally with the making process.

The fruits of my labours are in the next post.

 

The 3D Pantograph Club, Part 2: Jon’s Machine.

3D Pantograph built by Jon Tremlett.

The Pantograph, finished and installed.

In the previous post you will have read my story about a 3D scaling pantograph built by my sculptor friend Ed. As I also mentioned, my and Ed’s friendship started after we realising we shared a passion for motorcycles and an interest in these rather esoteric sounding pantograph things. So in this post I’ll shed some light on how it all came about.

The 3D pantograph, pictured above and covered in this post is a machine I built for a young artist a few years ago after being recommended for the work by another modelmaker. It is in some ways quite different to the one built by Ed, though in others it shares many similarities. There are no given set formats for these machines and so each is a direct response to a brief from the person who’s going to employ it. In my case the machine was to be wall mounted and capable of achieving quite a high level of accuracy, with variable scaling ability anywhere from 2:1 to 4:1. The artist sculpted in clay so no cutting actions needed, purely surface finding. As a consequence, this variability and need for precision dictated many of the design and fabrication decisions taken during construction, not forgetting the ever present need to work within a tight budget.

Cheverton Pantograph at soulcraftcandy.

The Cheverton pantograph used for reproducing scaled sculptures in alabaster.

To be honest I had never heard of a 3D pantograph when the job first landed in front of me, but all became clear as I took to the internet and arranged to go and visit one, currently residing in the archival warehouse of the Science Museum here in London. This particular machine was known as the Cheverton pantograph, named after the victorian industrialist who designed it for the manufacture of carved alabaster busts from scale models. It is a beautiful machine, quite a bit smaller than I imagined and a great example of a style of engineering design, lots of architectural references, so loved by the victorians. I freely admit that this machine heavily influenced my design, though it must be said that aside from some mentions of odd machines in America and Italy there is very little out there for the budding pantograph builder to study in order to construct their own. The Cheverton machine showed very clearly the pivoting arm for scaling pointer mounting, the different length pointers for achieving correct scaling and most important of all, a compact system for creating the two rotating turntables that enable the sculptor to access all points around a form.

3D pantograph by Jon Tremlett

The first iteration in the studio showing basic scaling function.

The image above shows the very first iteration of the machine temporarily installed in the artists studio. You can gather roughly how it works from the position of the two pointers relative to the positions of the two eagle sculptures positioned on the boxes. This was very much a prove out exercise, to make sure we were on the right track and to confirm some aspects of the geometry whilst I was building the rotating table structures. Because there was little or no documentation covering the detailed design of these things, it was quite a challenge to work out the exact geometry which governs how the machine works, and thus achieve the level of accuracy demanded by the artist. We encountered many problems to start with but overcame them once we’d realised what was going on. The essential premise is this: Firstly, the exact centre of the ball joint at the root of the moving boom needs to be on exacly the same line as the centres of the two scaling pivot joints. These three positions must be aligned by a straight line in space. Secondly, another straight line must pass through this ball joint and the two tips of the pivoting pointers. And finally, this latter line must also pass through two points at the centres of the tops of both of the rotating turntables. Simple enough you’d think, but a devil to work out without prior knowledge.

3D pantograph components by Jon Tremlett

The main pivoting components made using machined scaffolding parts and a lot of aluminium.

The scaling function of the machine is achieved through the relative positions of the pointer pivots along the main boom. For example, if the scale required is 3:1, then the second pivot would be three times further from the ball joint than the first. So if the first is say 500mm from the ball, then the second would be 1500mm from the ball joint. The pointers are also of different lengths in accordance with the selected ratio and correspondingly, the relative positions of the turntable centres needs to adhere to these spacings too. This means that for a machine like this, where an infinite degree of variability was requested (anything between 2:1 and 5:1), everything needed to be adjustable and lockable. Hence the pivots slide along the boom, the pointers slide through the pivot blocks, the turntables slide along their guide rails and finally, the chain drive that connects the turntables, which must turn in unison, expands or contracts in order to maintain chain tension across varying distances.

Rather than plough on endlessly, I’ll leave you today with some captioned photographs of the build which I hope will serve to fill in some of the background. Sadly I don’t have any more recent pictures, the machine was moved when the artist changed the location of his studio and I haven’t managed to gain access yet. I will keep trying though.

3D pantograph detail by Jon Tremlett.

Detail shot of the short first pointer locating small turntable centre.

 

3D pantograph detail by Jon Tremlett at soulcraftcandy.

Turntables, rails and chain drive under construction.

3D pantograph details by Jon Tremlett at soulcraftcandy.
Detail of the chain drive using proprietary bicycle components.

3D pantograph details by Jon Tremlett at soulcraftcandy.
The complete turntable and chain drive assembly ready to be installed.

 

 

From blank sheet to finished picture – part 2.

Norton_wash1

In the last post I showed how I create the base drawing for one of the small colour images I’ve been making recently. Now it’s time to take a look at how the colour and ink go down onto the paper. There is no right or wrong way of doing this, we are all individuals after all and our working methods all differ accordingly, but this is how I do it. There are about seven steps involved, and they pretty much alternate between applying colour washes and inking in. I have a preference for building the image from the centre outward so this is where I start, engine, chassis and other cycle parts.

 

Greys go down first, in this case Payne’s Grey, slowly building up in layers to give shadow where I want it, form where I need it and a backing for black areas which may contain a high or low light. Using a very small brush with barely any paint on, things start to take shape. There is a strangely imprecise precision to the process. Next come the smaller areas of browns, ochres and blues which begin to define the ground and sky reflections on the various metal parts. I leave the exhaust for now as I find this easier to do later, working within the confines of the outline after it has been inked in.

Norton_ink1

With the core of the image coloured, it’s time for the first pass with the technical pen, and being an old fashioned kind of bloke I’m still very fond of a good Rotring pen, in this case a 0.25mm nib width. The tightening of the detail that this achieves also has the benefit of allowing you to see where you may need to apply a bit more colour, or even a different colour, to an area which needs a bit more punch. You’ll notice I’ve also applied wash to the front and rear brake areas in this step to put myself in the position where the core of the bike is very much done. The frame rails, which were washed all in grey are now mostly black apart from a highlight line and I’ve applied solid black in selected areas to bring other details to the fore and create some depth.

Norton_wash2

This second wash stage involves getting the rider figure underway and laying the base colour pieces to the wheels as well as getting that tricky curving exhaust sorted out. As with the frame I put grey on the wheels and tyres in the places where I know I’ll leave gaps in the black of the ink, and apply this same method to parts of the rider like boots, helmet parts and goggles. Now, a quick word about that exhaust. Back when all of us budding designers were drilled in the fine art of marker rendering, it was obvious after a while that the practice involved learning a few, what I would call, conventions. Little techniques for doing curved surfaces, metal parts, areas of high gloss, textures and chrome amongst others. Although I haven’t picked up a marker in years, some of them remain useful when dabbling in other media. Shiny exhaust pipes are a case in point. A grey line to denote a horizon below which a brown area denotes ground reflections, and finally a blue upper area to signify the sky. Simple and effective, with some extra colour tones around the cylinder head exit where the metal changes colour due to the heat.

Norton_ink2

Time for more ink using the same approach as before, tightening detail and bringing definition. The wheel outlines get some attention using an ellipse guide for neatness, to be honest my freehand ellipse drawing is not what it used to be, and picking out a couple of details on the jacket and such will remind me not to wash over these at the next stage. The bike’s going to be a golden yellow colour so that’s what is coming in the next installment.

 

 

 

 

The 250 build, nearing the end.

A slight diversion today as finishing the story of the 250 build is way overdue. So some words and pictures of painted bits, metal bits and a nice piece of leather.

 

With three coats of base black applied, a series of white stripes were then masked and added. Everything was left for a couple of days to harden up before a very fine rub over with extra fine paper prior to the lacquer going on. For reasons of cost more than anything I’d elected to use rattle can lacquer rather than 2-pack on all parts apart from the fuel tank, which would be treated to a good couple of coats of petrol resistant lacquer, again from a rattle can. In retrospect I wish I’d gone the 2-pack route but it made the whole paint phase way too expensive, the petrol proof stuff works well but has yellowed in places and was quite tricky to apply evenly. With the lacquer all hardened it was time for a good polish and I can’t recommend Autoglym Super Resin Polish enough. Fantastic stuff and everything was just so shiny shiny.

Two important pieces of metalwork remained to be fabricated as all the painted parts made their way onto the bike for the final assembly. I knew the area at the back of the seat needed tidying but hadn’t been able to do much about it without the seat so it was stroke of luck that the seat arrived back just in time from being recovered. The first task was to make a piece to shut off the open area between the new mudguard and the seat mounting assembly. this then wrapped over the seat mount and formed an infill sitting below the rear of the seat base moulding.As before I worked it all out with thin card first which meant I could create a pretty accurate template for marking and cutting the sheet steel which was cut flat and then bent up in the bench vice.

For ages I’d been wondering how to finish off the rear of the seat. Knowing that there would have to be some kind of cover plate didn’t seem enough, there needed to be something else in there to give a more finished look. The answer came to me out cycling one day when I spotted and old bicycle with a little pouch hung from the back of the saddle. I ventured onto the internet to see what I could find for motorcycles. As it turned out, not too much unless I wanted something that looked like it had fallen off the back of John Wayne’s horse, and tassels are definitely not my thing. Taking the bicycle route proved more fruitful and in a fit of extravagance I splashed out on this lovely little number from Brooks the saddle makers. I quickly made up an angle bracket to fix the panel to, mounted to the seat base, and again using some card drew around the profile of the seat and transferred it to another template for cutting. A couple of holes and two slots later I had a neat little cover panel that the pouch straps attached to directly.

 

With these two new parts painted black final assembly could continue apace, my deadline for borrowing the workshop was looming.