#84 In my last build post I machined up the crank disc. Before starting on another part I finished it up and added a .250" stainless steel shaft. I included the 'connecting rod' in the picture, with the use of my modified two piece version of a 'crank screw'.
#85 It was time to get back to the 'floor' and finish it up by drilling all the counter sunk holes.
#86 The 'base' shown in this photo required an assortment of clearance oles and tapped holes. I need to get back to this piece and mill the two slots for the 'anchor lugs', and mill the 1/2" wide clearance slot for the flywheel. There are a few "fake" details on this plan that I will omit, but the "optional" draft (angled sides) detail will add a nice visual that's worth the effort.
#87 In the picture below, and from the top down is the 'floor', 'sub base', and 'base'. I broke off the tip of a #44 drill bit in the 'base while drilling the second hole at the top to be tapped 4-40. Luckily I was able to plot the location, and flip over the base to drill from the underside. When I hit the broken off piece I stopped the machine and pushed it out. Two bits hit the can, but much better than loosing the work piece.
#88 To make the 'bearing's' I started by drilling and tapping them from the underside.
#89 The optional 5/8" hole detail was very strait forward. Using a 1/2" collet mounted edge finder, I zero out the spindle axis on two edges of the work piece. After shifting the tables to the proper location, I switched it out for a 5/8" collet and center cutting four flute end mill to add the hole.
#90 On a second 'bearing' block I wanted to try out the idea of eliminating the "optional" hole detail, and adding an arched detail at the bottom instead.
#91 With the experimental stuff out of the way, it was time to profile a usable 'bearing' block and continue on with the build's progress. I scribed the profile lines as a way of over seeing the cuts I would make using calibrated table moves. I determined the angle to be 20 degrees, and used an angle plate taped to the fixed jaw to set up the part for milling.
#92 Before milling the taper's it seemed a logical first step would be to mill down the upper part of the 'bearing' block to a 3/4" width by taking off a 1/4" from each side.
#93 The fist step in making the bearing cap detail was milling down 1/8", and up to the scribed line at the 9/32" radius. In the plans there are fake hold down studs and nuts shown. I don't care for this "fake" detail and I will not be adding them to my build. The rounded cap detail is cosmetically pleasing, adding the phony hardware seems to cheapen it with dishonesty. I think I'll pass on this detail, thank you.
#94 The next step was to machine up some steel buttons to aide in the hand filing needed to create the rounded bearing cap detail.
#95 Below is a picture of the bearings finished up with the cosmetic caps filed to shape. There is a faster and more accurate way to create these from two pieces by drilling a hole to match the radius, and adding a machined bushing after milling down the cap 1/8". The bushing will be held captive by the top of the (milled down) block which will be higher than the center-line of the drilled hole. Depending on the metal of choice, a little Loctite or solder will hold it together nicely.
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