15-11-2022, 12:42 PM
I have machined hundreds of castings over the years but not attempted to machine a new crankcase although I have one as a " retirement project ".
Having a casting is one thing,but is it dimensionally correct,missing any bosses etc,porous anywhere particularly around the oilways?
I've always thought the first casting off a pattern to machine the worst because you might see it's shortfalls or faults when you machine it up.On a one off you don't get the benefit of that.
Plus the fact all the set ups to do the one off and particularly machining the crank/cam and oil pump centers which have all got to be correct to a couple of thou.
The thing that worries me most about a c/c is the internal oilways either breaking out or being porous .
I use a Bridgeport milling milling machine with a raising block on the head and a crankcase would be on its limits of size I think.
I believe Paul Bonewell has machined crankcass in the past ,I think he has a horizontal borer to do them.
Having a casting is one thing,but is it dimensionally correct,missing any bosses etc,porous anywhere particularly around the oilways?
I've always thought the first casting off a pattern to machine the worst because you might see it's shortfalls or faults when you machine it up.On a one off you don't get the benefit of that.
Plus the fact all the set ups to do the one off and particularly machining the crank/cam and oil pump centers which have all got to be correct to a couple of thou.
The thing that worries me most about a c/c is the internal oilways either breaking out or being porous .
I use a Bridgeport milling milling machine with a raising block on the head and a crankcase would be on its limits of size I think.
I believe Paul Bonewell has machined crankcass in the past ,I think he has a horizontal borer to do them.