The Quarter-Horse Stands Up - PMR #4
Episode 5 - Stud Farm and Pillow BlocksBack at it after the holiday weekend.
Since the crosshead will be coming up shortly, a 240 grit Flex-hone was mounted in the mill and, with plenty of oil, the cylinder bore and the frame bores were smoothed out. This was followed by a 400 grit Flex-hone.
With those finished, next up were the pillow block and bearing caps. I aligned the castings, clamped them to the table and drilled and tapped holes so that they would remain aligned for the rest of the machining.
The stud heights will be adjusted after both are machined.
I measured the draft angle and set the angle vise to match and then cleaned up the casting faces.
Much more fettling and sanding to do later. For now, the bottom and sides are cleaned up.
Mounting holes drilled.
Next up, the threaded mounting holes for the pillow blocks. Much cranking back and forth and light hammer taps until I had the base indicated. There was a bit of bouncing on the DTI dial from the casting surface but it’s within .003” end to end.
The eight mounting holes spot drilled per the drawing.
Now, 8 more studs. The ends were slightly crowned and then each was marked for thread depth.
First test is good.
Rinse and repeat seven more times.
Then eight nuts to mount the pillow blocks. I’m getting better at the nuts. Thanks, Dave.
Connecting RodThis vise was a CF acquisition a few years ago. Hasn’t had much use but for some parts, it’s been very useful. 45 minutes later, the vise is square to the table and vertical.
Now, the rod is indicated to find center.
Drilled and tapped and a center hole is added. The center pop is not on the drawing but it will be useful.
Then, a .04” slitting saw to separate the cap.
The casting halves were about .020” out of alignment.
The con rod was moved to the lathe. Now the center hole has a use. Easy cleanup at this point.
Now back to the mill for facing both ends to width.
Then a center-cutting end mill to slot the part. Two passes, .45” each.
The part was leveled, supported, clamped and generally made immobile for drilling and reaming.
One end finished.
Then the clamping was reversed for the other end.
Drilling for an oil hole.
Followed by fettling and sanding.
Much more finishing to do.
Crank PinThis part has a center turned between shoulders. Instead of endlessly switching between left and right cutting tools, I ground a .5” thick tool just a bit narrower than the width needed. First, dimensions were marked out with a narrow groovng blade.
Then the part was turned.
And, done.