A flathead V-8 engine

The next operation was to drill all the oil holes from the throws to the main journals. These are .062 diameter and a standard jobbers length drill will just make it through by holding about .25o of the shank.
I set up my angle table for this operation and indicated it true both for parallel and angularity. The fixture plate was then mounted, indicated and clamped.
The crank was clamped in place and I used the same procedure for aligning the throws as I did when I machined the counterweights. I then found the center of the crank with an edge finder and picked up the scribed layout line for the hole center.
The hole were first drilled with a #2 center drill which gave me a .062 pilot hole. I then proceeded to peck drill with the drill going down about .125 at a time and pulling it out to clear the chips. No need to have something nasty happen at this point.
When I saw bits of aluminum come out of the hole I knew I was through. All in all it wasn't as bad as I thought it was going to be. I used a brand new drill just to be sure.
gbritnell

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Here are the finished holes. All that's left to do is chamfer the edges.
gbritnell

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Now the easy but tedious part, radiusing all the corners and edges, filing and polishing.
 
Gentlemen,
The crank is finished. I spent the better part of today, burring, filing and polishing but it was completed without incident, oh yes and tweezing little slivers of steel out of my fingers. I set it up on blocks on my photo shooting stand and took picss of it rotated in different positions. On to the connecting rods.
gbritnell

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I put together quite a few full size engines and I'm wondering if there is a procedure for balancing the rotating assembly, or does the size of this make it pretty much a non issue? Very nice work, and I would think it's got to be much easier on the back than lugging around the Ford FE cranks and blocks I'm ussually working with. Mike
 
Hi Mike,
On some of my cranks I have no counterweights, on others I have full counterweights on each throw. The last two engines I built I replicated the shape of the full sized crank. I think with this scale it's pretty much of a non entity. They could be static balanced but although I know how a full sized crank is dynamically balanced it would be hard to replicate in this small scale.
Thanks for watching,
gbritnell
 
With all the major parts machined it's time to start picking away at all the small bits and pieces.
I turned up all the main bearing inserts from bearing bronze rod. They were split and fitted to the crank and block. The caps were drilled for stop pins to keep the inserts from spinning. The inserts were drilled to match the oil passage in the block.
I turned the flywheel from 12L14 steel (4.25 dia.) and drilled and reamed the mounting holes to match the crankshaft.
I turned the blanks for the timing gears, steel for the cam and brass for the crank. The cam gear will be pressed on with no actual way to align it for timing so the crank gear will have 4-.062 key slots, one lined up with a tooth, one lined up between two teeth, one a 1/4 between the root and tip and the last tooth 1/4 on the other side of the root. This will allow me to set the cam timing within 3 crank degrees which will be close enough.
The gears are 32 D.P. and I just happen to have a set of involute cutters that fit the number of teeth I needed.
The teeth were cut on the cam gear and then it was set up on the rotary table to have some slots milled into it.
gbritnell

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Gentlemen,
Well I'm back from Cabin Fever so it's time to get back to work. The first thing I wanted to do was finish the block. I need to do this so that I can fit the lifters, valves and such so that I can move on to the other parts.

I had the liners machined prior to Cabin Fever so the first think I did was to wash the block with hot soapy water to remove any oil and swarf that might be in the water jacket area. I made up a drift plug that slipped inside the liners so that I could tap them in place. I only went for a .0015 press fit both at the top and bottom. This was augmented with Loctite. The block was warmed with a heat gun and the liners were tapped in place until the shoulder on the sleeve bottomed out. I left the sleeves about .015 long so they could be trimmed flush with the head deck afterwards.

I turned up the valve guides from bronze here again trying to maintain a .0015 press fit. The valve stem diameter is .09375. A specially formed tool was made to fit over the tapered end of the guide so that they could be tapped in place. Once I had all the guides inserted I made and pressed in the valve seats. These were made from 1144 steel.

I had a seat cutting tool in my drawer full of specialty cutters but the one with the .094 guide was just a little bit small so I had to make another from drill rod.
Once the tool was made the seats were all cut by lightly turning the tool by hand and just shaving off the metal.

The angle table was then set up on the mill and the block mounted to the original fixture plate. The angle was set for 45 degrees and the table and fixture plate were adjusted until I got a -0- reading in both X and Y directions. The tops of the liners were then trimmed flush with the head deck.

The next step was to get out all the burrs, mounted stones and files to clean up all the machining marks. I spent about a day doing this. The final process was to hone all the bores to get them true and to size. I had mentioned earlier that I had to make my own hone due to the fact that the bore is an odd size (.832 dia.) This is really a messy job and once finished the block had to be washed with solvent and then hot soapy water again.

I can now say that the block is finished.

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