Phosphor Bronze

vibrac

Well Known and Active Forum User
VOC Member
Like many of us I have been spoilt by the Vincent spares availability so when I have to make a bush for a crankshaft for another bike with internal and external diameters in the range 1" to 1-1/2 inch out of PB1 I am a little apprehensive:eek: I have standard TCT ( tipped ) turning and boring tools will they be OK?. I am also a bit unsure of cutting speeds, the web is talking about 700+ ft pm that seems fast? finally due to the cost I have located a cheap solid 2" PB1 bar so I will have to drill a pilot first any tips on drill sharpening? . I shall rig up a coolant supply any suggestions on composition?
My lathe is a big old Harrison but the throat is small so the work will sit in the 3 jaws against the chuck machining length about 1-1/2 inches
 

Magnetoman

Well Known and Active Forum User
VOC Member
I made the small end bush for my 1928 Ariel from PB1. Looking at my notes, I used a carbide insert in a boring bar to turn the ID to somewhat less than the desired figure, then reamed it to size with a HSS reamer. The fact I used a carbide insert in the boring bar doesn't mean the material needed it since only in unusual circumstances do I use anything other than carbide. My notes don't give a figure, but typically when I use a reamer I start with an ID that's ~1/64" smaller than the final size. Anyway, my notes don't indicate PB1 behaved in anything other than a gentlemanly manner.
 

vibrac

Well Known and Active Forum User
VOC Member
Thanks for that it gives me confidance unfortunatly the ID is over 1" so I shall have to fine bore it I expect that the fine finishing cuts will be difficult at least the stated working clearance will be fairly wide at .003"
 

Cyborg

Well Known and Active Forum User
VOC Member
You asked about phosphor bronze, but if you happen to use oilite at some point.... might be worth having some of these inserts on hand. I should take my own advice.

 
Top