My 1936 Flying Squirrel Clutch

[martin@marmoy.com]

Good morning,  can someone please help me with information regarding my clutch . I am a recently new person to Scotts so please forgive my ignorance. The problem I have is that the machine I own was bought as a non runner so I dont have that background to depend on. The issue is I cant get the plates to separate enough when I dip the clutch so it drags. I know enough to realise this is controlled largely by the 3 pins that are screwed in up against the thrust bearing but ………..  the more I screw those in the more the final cork plate protrudes beyond the clutch basket. This means its tangs are not retained by the basket itself. In essence the thickness of all the plates is to much for the depth of the basket. When I fit the final end plate with the spring studs and 3 x adjustment pins, the final plate is only just retained by the basket fingers and therefore when I pull in the clutch it sticks out beyond the basket and is allowed to rotate and / or drop down thus making it useless when I release the clutch lever again. You will probably be thinking I’ve either got too many plates, turned the 3 x adjustment pins in too far or I haven’t pushed the clutch basket far enough onto the main shaft. All these things I have checked, checked and checked again. So I’m left wondering if the plates themselves are each too thick ? Can anyone advise me please what the max thickness should be for the 4 x metal and 4 x cork plates please ?

 

[BRIAN MARSHALL]

Although cork inserts give a nice smooth and oil-resistant clutch, they can give problems if too soft a grade of cork has been used, that is to say that some initial clutch movement is ‘lost’ as the cork expands as spring pressure on it is removed as the lever is pulled. My first action here would be to remove one friction plate and one plain plate, then see how it behaves. IN the late 1920s there was a ‘slim’ version of the clutch, intended for less plates, and perhaps you have one of those….

[martin@marmoy.com]

Thanks Brian,  I’ll give that a try if no-one else can tell me what the thickness should be for each plate.

 

[BRIAN MARSHALL]

I can quote chapter and verse on original sizes for the ‘Ferodo’ type wired asbestos ‘button’ clutch inserts, but have nothing on file for cork inserts, however they were probably the same size. All a bit irrelevant when we don’t know the type of clutch ‘basket’ that you have.

[BRIAN MARSHALL]

I just KNOW that you want to KNOW those original dimensions !! Here goes…

On the friction plates there are 42 inserts on each one, 1/2″ diameter x 1/4″ thick.

On the chainwheel/basket there are 40 inserts 9/16″ diameter x 3/8″ thick.

While I am ‘at it’ please note that the clutch runs on 36 bearing rollers that are 3/16″ X 3/16″

[martin@marmoy.com]

This information is excellent Brian.  I can tell you that the number of barrel rollers I have on the chain wheel are 30 !!  The depth of the clutch basket fingers is ( from the backing plate – not the cork button) is 23mm.  ( being a mere lad I use metric ) plus there is a band round clutch basket.  So, what have I got there please ?

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