7mm Mickoo's Commercial Workbench

[Dan Randall]

Hi Ozzy, the princess / turbomotive looks like 20 spokes. Confirmed because opposite spokes align in a straight line.

The duchess looks to me to have 21. It's certainly an odd number as, to my eyes, opposite spokes are offset from a straight line.

I’ve often wondered how the engineers of old, were able to divide 360 degrees into uneven amounts, before the days of electronic calculators and computers?…


Regards

Dan

 

[OzzyO]

I’ve often wondered how the engineers of old, were able to divide 360 degrees into uneven amounts, before the days of electronic calculators and computers?…


Regards

Dan

Log table is your answer and slide rules. I did use log tables but I've not used them for 40+ years, a slide ruler never used one, I don't think that I would want to.

ATB

OzzyO.

 

[MarkR]

When I was an apprentice draughtsman, I used to draw slide rules!

slide ruler never used

 

[timbowales]

I've forgotten how to use both log tables and a slide rule, must be getting old

 

[mickoo]

I used slide rules at school in tech drawing class and my apprenticeship along with Trig tables, not as a general means of education but as an alternative if you were out in the field (work, not school) and your calculator was naff. It was also a good way to discipline your math work flow and a good test of correlating several pieces of information to get an answer.

Back to wheels, it's simple really.

Princess Royal has 20, any other number is incorrect, whatever the source.



Princess Coronation has 21.



The one area you need to watch out for are the reinforcing webs, these were only applied to first few Princess Royals, not sure right now exactly which ones, but think it's limited to just the first three, after that webs were not fitted.

The wheels are interchangeable so the webbed wheels may have moved around but the first three lost them at some point quite early on for standard wheels.

 

[Scale7JB]

Could really do with a B12 / D16 wheel as well

JB.

 

[mickoo]

Could really do with a B12 / D16 wheel as well

JB.

I have a B12 in next years build queue

 

[Rob R]

Could really do with a B12 / D16 wheel as well

JB.

That's 2 wheels 'cos they are different sizes.
Still only 1 rabbit hole though......