+- Austinsevenfriends (https://www.austinsevenfriends.co.uk/forum)
+-- Forum: Austin Seven Friends Forum (https://www.austinsevenfriends.co.uk/forum/forumdisplay.php?fid=1)
+--- Forum: Forum chat... (https://www.austinsevenfriends.co.uk/forum/forumdisplay.php?fid=14)
+--- Thread: Boring out 3 brg crankcase for 2 brg crank (/showthread.php?tid=9381)
Boring out 3 brg crankcase for 2 brg crank - Austin in the Shed - 22-05-2024
Anyone know what diameter cutter I need to use to machine out the centre bearing to clear the crank?
RE: Boring out 3 brg crankcase for 2 brg crank - Peter Clayton - 23-05-2024
You could give VINCE LEEK a call he doesn't do this mod any more (now semi-retired) but may be able to give some advise.
RE: Boring out 3 brg crankcase for 2 brg crank - Robert Leigh - 24-05-2024
I have just measured the one Vince Leek did for me a few years ago; as near as I can judge it's 4.75 inches diameter. I took a picture which I hope is of some use.
I think it is unlikely that I shall use this crankcase, so I am open to offers.
RE: Boring out 3 brg crankcase for 2 brg crank - Austin in the Shed - 25-05-2024
Thanks for the reply Robert.
In the end I measured a two bearing case,well the thickness of the aluminum casting surrounding the bearing sleeve and took that away from the crank / cam centres and got a similar figure to you.
I did speak to Vince for his advice which was very helpful,I’ve never machined one out before in thirty odd years.I’ll post a picture of the set up of how it was done when in the workshop.
RE: Boring out 3 brg crankcase for 2 brg crank - Austin in the Shed - 25-05-2024
Here in the lathe,I did consider doing it on the Bridgeport as I can get around 2’ between spindle and bed if necessary but settled for this.
RE: Boring out 3 brg crankcase for 2 brg crank - Robert Foreman - 25-05-2024
Good work with the flying nail Dave.