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+--- Thread: CWP Tooth Geometry (/showthread.php?tid=1050)
CWP Tooth Geometry - Chris KC - 07-04-2018
Here's an old-school question...
The recent thread on gearchange and final drive ratios inspired me to have a rummage through trunk #3.
To my slight surprise I found I have a diff gear set with 45 tooth crown wheel attached, in quite good nick but with no matching pinion. (You can see where this is going...)
I know very well it's not best practice, but even the likes of old Jack was not above mixing CWP gears if needs must, and I have a Nippy as wouldn't say no to a 5.625 ratio.
The simple question - tolerances aside - are the 8 tooth pinions interchangeable betwixt the various crown wheels which used them (41, 42 & 45, to my knowledge)? Or is there some difference in tooth geometry other than simply the number of teeth? I can't help but observe the 45 visibly has a lot of teeth, and it sows the doubt that the 'standard' pinion might be too fat in some way.
Strange feeling undoing grubby bundles tied up with string by my father more than 25 years ago. Can almost feel him peering over my shoulder grumbling 'what are your pilfering fingers doing in trunk #3?".
RE: CWP Tooth Geometry - Ian Williams - 07-04-2018
Yes there is a difference in tooth geometry so you need to find the right type of pinion.
RE: CWP Tooth Geometry - Chris KC - 07-04-2018
(07-04-2018, 04:04 PM)Ian Williams Wrote: Yes there is a difference in tooth geometry so you need to find the right type of pinion.
Thanks Ian, I thought that was a bit much to hope for...
Chances of turning up a stray Nippy / van pinion in good condition seem remote, does anyone happen to know how to ID them?
RE: CWP Tooth Geometry - Ian Williams - 07-04-2018
They do turn up if you can spot them, most obvious is that the pinion is more deeply cut than the others as this picture hopefully illustrates.
DSC06416.JPG (Size: 248.81 KB / Downloads: 193)
RE: CWP Tooth Geometry - Chris KC - 07-04-2018
I'll keep my eyes peeled - many thanks for the pic Ian
RE: CWP Tooth Geometry - Charles P - 08-04-2018
There are way more 5.625 crown wheels to be found than pinions, precisely because of the deeply cut teeth.
C
RE: CWP Tooth Geometry - Chris KC - 08-04-2018
Only thing I found at the autojumble today was a bacon sandwich!