Scratchbuilding
- Get yourself a good digital calliper
- jeweller saw with 4/0 or 5/0 blades
- a set of good needle files #4 cut (flat,round, taper,square)
- Archimedean drill and 1.5 mm tool holder
- Order some small sheets of NS and brass in different thickness (0.1, 0.25 and 0.35 K&S), a strip of 0.5 mm PB
The harder the metal the better because that will keep flat more easily than soft metal. Use some 2mm MDF as sacrificial material for cutting metal sheet.
Grind the tips of your digital calliper to a sharp 45 degrees so that you can engrave parallel lines into the blackened metal where you should cut with the jewellers saw, and just make a start.
Wheels
Frames
Nigel Ashton Cambrian 0-6-0
Simpson Springs
Aug2008.pdf#page=7
A relatively recent but now almost universal addition to 2FS chassis assembly are so-called 'Simpson's springs' named after Mick Simpson, stalwart of the North Eastern Area Group of the Association. These consist of very fine ( 41 swg) phosphor-bronze wires which rest on the stub axles through slots filed out of the bearings' top hats. The other key part of the Simpsons is the drilling out of the bearings to 1.6mm (but only once the chassis is assembled square and true!). I must admit I'm not entirely sure how these work - the small amount of play certainly helps maintain track continuity and the springs may well also help pickup. Whatever their mode of action, they certainly work with quite dramatic effect. I did one of my track tests a la my MRJ articles in issues 101 and 104 - one hundred times stationary to stationary up and down a 2ft length of track while watching a not particularly engrossing television programme (the television PHOTO 2 contributes little to the test but does make it more bearable): the 'unsprung' version stalled nine times, the one with Mick's springs didn't stall once! (Photo 2)
Gears
"Gears often have slight roughnesses or ‘burs’ on them as part of the manufacturing process. It is worth rubbing them, flat on their sides, on some fine wet and dry to remove these. Also worth taking a small screwdriver blade and just running it lightly through each ‘valley’ between the teeth to make sure that there is no debris in there to interfere with the meshing. If two gears are to run side by side on separate shafts, e.g. the worm wheel and the final drive gear on the axle, it is also a good idea to slightly chamfer the edges of them, just to make sure they run smoothly past one another." Jim Watt
"You can watch me de-burring a gear in Part 16 of my series of videos on constructing a Jubilee chassis (link to the playlist from the Association home page). The de-burring starts at about 2:20." Nick Mitchell.
Coupling Rods
Steel strip
Weight
Cooper Tungsten
Details
"If you can't do it to scale then don't do it" Tim Watson