Bob,
A larger number of fine splines has more surface area thus more strength
than a smaller number of coarser splines. Also coarse splines are cut
deeper which reduces the shaft cross section & strength.
Your 1.25" 10 spline is likely equivalent to the 1.06" 15 spline.
On the wheels, I would speculate that the cross sections would have to
be a lot thicker with eight splines but the Rudge-Whitworth spline is a
special case of it's own since the "splines" are a semi V shape not a
conventional spline.
I don't know enough about the Morgan design philosophy to speculate on
why they did it. You could go here join, & ask on the Morgan list.
http://www.team.net/cgi-bin/majorcool
Sorry I'm not more help,
Dave Russell
BN2
Bob Nogueira wrote:
> Please excuse this question if it is a bit off topic but I figure this is
> the best place to get an answer that I can understand.
> What effect do the number of splines have on the performance of a shaft?
> The project I am working on has a shaft with splines on each end, The shafts
> fit into sleeves to transfer the turning motion. The One end of the shaft
> has 10 splines ( 1.25 inches dia while the other end has 15 splines on a
> 1.06 dia. Since the load is the same on both ends of the shaft I was
> wondering why they did not use the same splines on both ends .
>
> Okay your thinking what is he talking about . Well on my Morgan (Plus 4 )
> the transmission is located about thirty inches behind the flywheel, An
> intermediate shaft is used between the clutch and the transmission input
> shaft with a muff coupler joining the transmission input shaft and the
> intermediate shaft. The clutch end of the intermediate shaft acts just as a
> transmission input shaft on a normal setup. The clutch end has the same
> splines as you would find on a transmission input shaft., ten. But the
> transmission end of the intermediate shaft ( the muff coupler and the
> transmission input shaft) have 15 splines . It seems to me that they would
> have saved time and trouble ( as well as not have to use a 'special'
> transmission input shaft ) by simply using the same splines on each end.
>
> This same question applies to wire wheels. While the axle may have 10
> splines why do the put all those fine splines on the wheel? Why not use
> wider cut splines ? What's the advantage of having more splines ?
>
> As always thanks for the education
>
> Bob Nogueira
|