From this and previous sessions, I found that my mill doesn't seem to move the distant I dialed into. I rely on the layout lines to locate the hole locations most of the time. Will have to check that out soon.
A square piece of brass was included in the kit for this engine running on compressed air. It measures 1/2" square and slightly more than 2" long to make the Cylinder Mount and the Cylinder.
I started by slicing up the brass stock on my bandsaw for the 2 parts freehand.
Next, the flycutter was used to thin the piece for the mount to 3/16", as called out in the plan.
The insert used is from AR Warner made of HSS.
Yet again, I was out by 0.004"... Really need to pay attention to creep up to the right size... I'll move on and rebuild any parts that won't work later.
The 2 sides were trimmed next.
I did it yet again - undersized by 0.006". What's wrong with me...
I decided to layout the hole locations rather than relying solely on the handwheels as I seemed not to get the distant dialed.
The first hole, 1/8" diameter. Again, I've not gotten the reamer. The 1/8" drill will have to do for now.
I should start drilling the holes from the top of the workpiece (the right side in the pix), which is the datum shown in the plan), but the top 2 holes (the 1/16" holes on each sides of the centerline). I wasn't confident in remembering how many turns I made and therefore started with those 2 on the centerline.
Holes all done. The 3 smaller holes to the right are right on the marks but not the 1/8" hole.
The plan calls for the hole in the middle to be counterbored.
I should have done the counterboring in one setup but... it is not very concentric to the through hole. That's the price to pay for not planing forward. Anyway, that's a good lesson learnt.
The 2 inlet ports (is that the name of the holes?) were drilled till each broke into the 1/16" hole on each side.
All done. Looks good... Hehehe...
The last part for this engine is the Cylinder.
This will be done in the next session. The truth will be revealed when I assemble the parts together.
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