Roll pins / Spirol pins

[hair bear]

Hi,
Doing some work on a friends Argocat, it has lost drive to some of the hubs. What appears to have happened is that the hubs are attached to the drive shafts by having roll pins pushed through them but these have either broken up or fallen out, I can't find any traces of them.
In the manual it says they are 5/8 x 2 1/2 Spirol pins.
So the questions are...
What is the difference between a roll pin and a Spirol pin?
Is 5/8 the size of the pin when expanded or compressed?

I'm guessing there is some wear in the fittings so my plan is probably to put some high tensile bolts in as there is room around the shaft for the head and nut but it'd be nice to know what should be in there before the bodging commences!

[TrevorJ]

https://www.spirol.com/company/products/prod_d.php?ID=50

I think a lot of poor designs place too much confidence in them ... I was wondering what they were called.

[hair bear]

Thanks Trevor,
I did a search and found nothing. Having seen them now I think putting bolts through will be the way to go - easier to aquire and easier to replace, particularly at the bottom of a muddy field.
I did wonder if the pins were designed to shear when overloaded but one failing would result in the other axles taking the strain and a domino effect.
A job for tomorrow if I can sneek out for a while...

[modelman093]

Roll pin is a single leaf curled round till the ends meet, so has a hollow centre. Spirol pin is wound round like a Swiss Roll so that it's almost solid.
Think that the size is "nominal" so if you have a 5/8 hole the pin will be slightly over size so as to compress when fitted.
Used to use a lot of them on horticultural machinery but mainly 3/16 and 5/16!

[hair bear]

Glad you posted that, made me go and look at the book again. 5/16 not 5/8! Ahem...

[hair bear]

Job done, for now anyway. 5/16 bolts did fit, so as you said the size was nominal.
Thanks for the help, another usable toy!