Tig I could hug you for those links.
I must thank juan974 for the ramp.skp which he posted to this thread http://forums.sketchucation.com/viewtopic.php?p=239767#p239767

I have modded his ramp file to get myself the closest I have been to completing this part.
I just need to reduce the center to 1mm diameter now and then I am done with it, any simple way?.
Circle slope.skp

Hi guys.

I have joined up in desperation because I am going insane trying to model a very simple part.
I can visualise the part in my head put I can not for the life of me draw it with pen and paper let alone sketchup.
Description of part:

A circle 5mm in height,10mm in diameter.
It has a 1mm diameter hole at its center.
Draw a line from the centre to the outside edge of the 10mm circle.
Now the tricky part to explain.......
I want to lower this line to 0mm on 'one side only' creating a smooth spiralish slope around the circle.
Does that make sense?.

I would appreciate any help or suggestions you can offer.

Rebo