RICK’S FIXES
Wonky windowsills? Builders without spirit levels? Rick takes an alternative angle on going straight
A builder without a spirit level and some useful workshop tips
LAST MONTH I asked if established engineering methods are essential if you find a homespun way to do a job successfully. To balance the argument, my current project shows the other side of the coin.
Ever since Joseph Whitworth ensured one man’s nut fitted another’s bolt, engineering standardisation has improved reliability through consistency and repeatability.
Imagine a builder without a spirit level. If he builds a window aperture with a sill that slopes and isn’t square, the window must be custom made, rather than an off-the-shelf replacement.
If I assemble my Scarlet Runner rear frame on a surface plate (see above, as featured on page 84), I can get all the fixings in plane – although the main frame of the bike isn’t straight, so it won’t fit. But if I build the rear frame to suit the front, it will never fit another frame – should I ever find one. Building the frame ‘square’ is easiest; set up with a surface plate and engineer’s square, right and wrong are clearly defined – but trying to make it fit around an inaccuracy elsewhere involves guesswork and lining up by eye, giving potential to create other inaccuracies that stack up to breed further problems.
The answer is always to build it ‘right’ and somehow adjust the bit that is wrong to measure up. Otherwise the series of errors complicate tracing the problem back to source and make it impossible to rectify – just as if you live in a house with crooked floors and windows, sooner or later you start leaning over to one side!
If you want to see more background on the Blackburne rebuilds, take a look at my Classic Bike Workshop site: rickparkington.co.uk
‘BUILD IT ‘RIGHT’ AND THEN ADJUST THE BIT THAT IS WRONG TO MEASURE UP’