I figure there are people on here that use the Neway cutters in one form or another. I am afraid of over cutting if using machine power to drive [rpm not slow enough] so what if I rotate and apply pressure by hand? Valve size is 1.170 int/1.050 Exh. Since this is a Crosley hard to see whats going on 4" down the bore; may have to omitt a cutter or put the pilot in after the cutter is at the seat to clear the cylinder wall, valves just barely clear. I just measured the Int. bore to valve pocket and it is at 1.155, doesn't add up to much seat..
Caution is your friend. If we have to do something over a few times slowly, it beats trying to find a replacement. We have all seen a head with the seat sunk. That's a quick way to kill airflow and performance.
Make an adjustable collar/stop that will limit the desired cut depth. That way you can sneak up on it a bit at a time. And if the cutter starts to chatter on the seat it's very difficult to fix that without using a solid stop. A good cutting lube is your friend too.
There’s cutters and stones. Can a stone be used by hand? I don’t know, but never had the juevos to do the with a stone at 10k RPMs. Seb , I might have what you can use, will take a few days for me to make sure I have the cutters for your seats but also need the valve diameter to know if I have the proper Pilot. Cost? I send the to you, you send them back.
I have always used them by hand. A few times I tried to use a machine to rotate them I have gotten chatter no matter how far I slowed it down. Eventually I did manage to slow it down to hand speed. So I have used hand since the 1970s when I first became aware of the "new thing" neway cutters. The dozens and dozens I have done were always by hand. (if I count the die grinder a hand tool) I think a Neway cutter is more accurate by hand anyway.
I think the Neway cutters are designed to be turned slowly, by hand, I have a few in smaller sizes that I use on old Brit bikes, and they came with a tee-handle to rotate by hand. A little cutting oil helps, too...
I’ve also done a ton of them by hand with Neway cutters. I would ditch the adjustable pilot and buy the correct size solid pilot but that’s a personal preference.
Only by hand. Unless you have a machine that turns really slow. If it were a 305 head you were cutting I would say use a zoomer and if you screw up get another head. But you are cutting something that cannot be replaced. By hand only is your best bet.
The Jalopy Journal
