The kit contents

The Windcheetah kit sold by AVD came with the main aluminium tubes (spine, cross-bars, etc.), joint castings, nylon mouldings, machined alloy components, and a set of special fastenings. All other components, including wheels, cables, transmission, and so on, had to be sourced separately. The main components of the kit are shown in the photo on the right.

Methods of coating the trike

When the kit arrives, all the metal components are untreated bare metal. You might want to leave the trike in that state, which, with a bit of polishing can great. Unfortunately, bare aluminium will oxidise (rather like rusting on iron and steel, but not as obvious), and is very soft so will scratch easily. For durability, and looks, the metal needs a protective coating. The AVD manufactured trikes come with the tubes anodised, and the castings powder-coated. Due to the relatively high cost of anodising, I initially looked at alternative means of coating the bike, including stove-enameling, and air-dry paints.

Stove-enameling is one of the traditional ways of coating all types of bike, and gives a tough, high quality finish. It is also relatively inexpensive. Unfortunately, it turned out to be impossible to use this method of coating, because to work properly, the coating must be baked on in an oven. This baking process would destroy the bonded joints. It wouldn't be possible to enamel the components first, and then bond them either, because the thick coating would prevent some of the components fitting together (e.g., the centre casting has to slide down the tube). I abandoned this method.

Air-dry paints overcome the problems of the baking process in stove-enameling. They are applied after the frame has been built (to allow the components to fit together), and cure at room temperature. Their main disadvantage is that they are not particularly tough, and it wouldn't be very long before the coatings started to show a lot of wear. As it turned out, the cost of air-dry paints was also quite high, and actually exceeded the cost of anodising, and powder coating.

So, the final choice was anodised frame, and powder-coated castings, just like the AVD trikes. AVD offer a coating option when buying the kit, but I wanted something different from the normal yellow and silver Windcheetahs; like one of my old bikes, I went for bright red tubes with black joints.

Anodising the frame

Anodising is an electrochemical process, which hardens the surface of the coated metal. Unlike paint, enamel, or powder-coats, the anodising becomes part of the metal being treated, and is subsequently very tough (the second hardest substance known to man in fact!). The anodising also allow the metal to be dyed.

I had my frame anodised at a local metal treatment company. If you go for a standard colour, this keeps the costs down quite a lot. Exotic colours need to be mixed specially, which could be 80GBP, even without the cost of the process itself. The other major cost when anodising is the setting up of the treatment baths. The small tubes that make up the Windcheetah all fitted into a ready-mixed bath, which the treatment company used regularly. The main spine tube was too big to fit in this bath, so would have required the treatment company to mix up a special batch of colour, in a much large than normal bath, and which would have cost a lot to do. Instead, we decided to treat the spine tube in two stages, coating one end of the tube at a time. The disadvantage of this method is that a seam line is created between the two separate coatings, but this is easily solved by arranging for the seam to be located under the centre casting, where it would eventually be filed away for bonding. The other problem we encountered was that the tube is very long, and it was difficult to get enough current to flow through the tube to evenly coat it (the first attempt resulted in a blotchy pink tube - horrible!). This can be solved be attaching additional electrodes along the length of the tube, arranging for them to be placed under the centre casting, and the seat castings, where they won't be seen.

In total, the anodising cost me 95GBP, which included 50GBP for the tubes to be polished before coating.

Powder-coating the castings

Powder-coating is a process in which a layer of powdered plastic resin is melted onto the surface of the metal, where it forms a very tough coating. When the castings arrive from AVD, they will have been machined where appropriate (e.g., thread holes), but will have a fairly rough, unfinished surface with visible seam marks. It would be possible to powder coat this surface directly, but the rough cast surface will still show through. The photo on the right shows a finished casting with an area in the centre left rough-finished. I cleaned the surface of the castings by hand, using a combination of files, needle files, sandpaper, and an electric detail sander. It took about 1 hour for each of the simple castings, and about 2 hours for the more complex castings. Once all the castings had been cleaned up, they were given a fine shot-blast, and then masked up ready for the powder coating. The most expensive part of powder coating is the masking (because it is very time consuming), and you can keep costs down by doing this yourself. I had the castings coated in high gloss black, and they look fantastic, as the photo on the left shows.

The cost of powder coating all the castings was 40GBP.

Sourcing bearings and bushes

The AVD kit comes without any of the bearings needed for the axle and pulley mounts, nor with the kingpin and steering joint bushes. These are available from various national distributors (e.g., BSL, Wyko), who seem to charge a lot for small orders. I bought them from Midland Bearings, who gave a very quick and helpful service, and charged me 25GBP, which was about a third of what BSL were asking. When ordering the bushes, make sure that you get bushes (known as `DU' glacier bushes), and not sealed cartridge bearings with the same number (i.e., MB1210DU bush, not 1210 bearing).

Sourcing glues

The Windcheetah is glued together using Loctite 638 Retaining compound, Loctite 243 Nutlock, Loctite 270 Studlock, and Araldite 2015 epoxy adhesive. Once again, people like BSL stock these, but they are expensive. I bought mine from the local branch of Cromwell Tools.

Wheels

The Windcheetah kit comes with the hubs, and you will need to supply rims and spokes. The back rim is a standard road-bike size, and it should be fairly easy to get hold of the Sun CR18 rim (or equivalent), and matching spokes. The front rims are much more difficult to get hold of. None of the shops in my area were able to source these rims, with the exception of Avon Valley Cycles, who would have had to order them from the USA. Also, the spokes for the front wheels are very difficult to find. Several shops offered to cut the spokes for me, but they probably wouldn't be as good as the ones that AVD supply. I eventually got the front rims and spokes from AVD, and had the wheels built by Bristol Bike Workshop.

Miscellaneous

Everything else required to build the bike can be bought at bike shops or tool/hardware shops. You will need standard cycle components including cables, chains (x3), front and rear mechs, chain-set, shifters (bar-end type), pedals, tyres and tubes, bottom bracket, and cassette. Useful tools include a work mate (invaluable for holding the trike during construction, especially when determining the correct alignments), gaffer tape for holding components in place, a taps to clean out the machined threads.

The next step

Having got everything needed to build the trike, its time to move on to the frame bonding.