Does anybody know what angle the teeth on the engine/intermediate/cam pinions are cut to? For a Dominator in particular, but I suspect the same for post war Nortons.
Did Donington Nortons go metric or did they stick with imperial?... or a horrible mish-mash of metric UNF BSF UNC Whitworth BA?
what question
- Log in to post comments
Do you mean pressure angle…
Do you mean pressure angle on the involute, why do you need to know this? If you are getting new gears hobbed the gearcutter should be able to shadowgraph the old gear to determine it. 99% of all gears use 20 degrees
- Log in to post comments
Hi Peter yes pressure angle,…
Hi Peter yes pressure angle, these teeth do look like a narrow angle. They are very small of course, but wondered if it was 14.5°.
Anyway I have found a workaround so I don't think I am going to need to have a new one fabricated.
I wonder how many shops still have imperial hobbing tools around.
You wouldn't happen to know what type of steel they used would you?
I reckon the two sprockets on the intermediate gear must have been broached - I can't see how they could have been cut - what do you think?
Steve
- Log in to post comments
Steel type
They would have been EN36 then case hardened. Sure they would have been broached, hobbing wouldn’t work with neighbouring sprocket
- Log in to post comments
hello now under EU build Rules All motors should be fitted with fixings of metric form and early norton twins timing gears angle are at 270 degree witch is opposite to 90 degrees against a vertical axes of 360 or zero , yours anna j