first off thanks: david,darren and nick the kind words help a project move a little easier
tom: i got the grey casting look by sand basting the cylinder head, the head is made out of 12L14 steel so it might blast different than mild steel.
as far as the valve seat's go i just set the head up in the mill and reamed the valve guides and without moving the head i used a 90 degree countersink to cut the valve seats.
then i just lapped them with 400 grit lapping compound.
today i was home alone, and i was able to get some work done
i started fabricating the crankshaft.
this is what i started with, 1/2" drill rod and 2 pieces of 3/4" x 3/8" cold rolled flat bar.
first thing to do is face off the longer of the two shaft's and center drill both ends. the center drilling makes the crankshaft look more like the original.
next i squared up both blocks of cold rolled
next thing to do is drill holes for the crankshaft and throw. these ones will be center drilled, drilled and then reamed to .499" .
reaming 0.001" under 1/2" makes for a nice snug fit for the crankshaft and throw.
here we have one throw done so i will have to do all of the above procedures one more time
and here we have both finished ready for the next step.
and the next step is to machine the end thrust cheek's, the picture show's what i mean.
i use a brass expanding lap to hold the parts to machine the end thrust cheek's. the brass lap was not designed for this procedure but if you take light cuts it will work fine.
now we can put all the pieces together and see if we have a crank. when putting all the parts together i use loc-tite red to help hold everything in place. after allowing time for the loc-tite to set i then drill and ream holes for tapered pin's. the pin's are driven into the reamed hole's.
tapered pin's in place
after the pin's are driven in place the end's of the pin's are cut off and filed flush with the crank throw's.
next step is to trim the ends of the crank throw pin
this crankshaft get's a 1/8" key way on in both ends of the shaft...........so here we go
first square the crank to the mill table, this ensures the key ways will be directly opposite the throw.
all thats left is to cut the key way and then turn the crank end for end and repeat the key way set up and cutting procedure.
here one end is done and the other is about to get a key way cut
with both key ways cut the next thing to do is cut the center of the crankshaft out. you can cut it out with a saw but i use the mill.
after cutting through just clean up the ends of the crank and you will have a finished crankshaft
the finished crankshaft
this is the way i have made all but one of my gas engine crankshafts (about 10 or 12 of them) and all have work without fail.
it is allot faster than trying to turn a crankshaft out of one piece in the lathe, i turned the crank for my fairbanks morse engine from a solid piece of steel, it took hours to get it right.
the crankshaft i made today took about 1 1/2 hours to complete.
well that's all for tonight as for tomorrow ..................... who knows
chuck
