Member postings for Mike Angelo

I had a BSA bantam a many years ago and copied an Austrailian's ( Hogan ?) tuning details that were publishished in the "MotorCycle" in the late 50s or early 60s .I carefully filed out the ports to the larger sizes specified ( may have made them a little larger thinking that the larger the better) but found the larger port sizes killed the air flow velocity and the power output was much reduced. So don't go overboard on the port sizes !

It's a shame that steam powered larger loco models were not covered in greater detail - model engineering is far too complicated for the BBC.

By using thread gauges ( either metric or imperial or both) it shoud be possible to define the the thread pitch . Making an impression of the thread with araldite ( apply penertrating oil before hand and allowing most of it to evaporate) it should be possible to double check the thread angle if you're not sure if its 55deg or 60deg.

Knowing these thread details any reasonably skilled turner can then turn a screwed shaft ( bolt) to fit the hub. It may be prudent to make the shaft out of high tensile steel (EN8 or better).

Knowing what the intended application is and the age of the tool would help in predicting the thread form.

It would make sense if the desired clearance ( or interference) on some parts was specified . Thus a bearing would have the radial clearance specified e.g. 0.001" for a 1.5" shaft. This would give the machinist some idea of what to aim for, even if the actual size was not spot on.

I share J.S's frustration regarding the cost of getting BS standards copies . Surely in this electronic age all these standards should be available on a public accessible website ?

If copies of standards were available in this way surely this would be a major benefit to all industry ?