I'm trying to turn some EN8 for the crankshaft of the little Demon V8 and I'm having a hard time getting a good finish. I had initially tried with a carbide tip but after some research people recommended using HSS as it's supposed to give a better finish. I ground a fresh bar with roughly 15-20 rake on top and a small radius and although it was an improvement over the carbide tip I'm still not happy with the finish I'm getting. I don't know if the tip needs more refining or if the speed and feed isn't right.
The bar is roughly 1" diameter and running at 420rpm with a feed rate of 0.002", which is the slowest feed rate I can get on the Super 7 without buying another gear to reduce it even further. Wondering if you can offer any tips/advice on how to get a better finish, because I'm worried if the journals aren't great they'll most likely pick up on the bearings.
The bar is roughly 1" diameter and running at 420rpm with a feed rate of 0.002", which is the slowest feed rate I can get on the Super 7 without buying another gear to reduce it even further. Wondering if you can offer any tips/advice on how to get a better finish, because I'm worried if the journals aren't great they'll most likely pick up on the bearings.
