Hi Everyone,
Don, Mossey & Eric you guys are too kind but I do really appreciate your comments and it makes me proud that this little project is an inspiration to others; is has also given me some great shop time and enjoyment so far and for me that is what it is all about.
Working on the exhaust valve chest casting and some of the related timing parts. The relationship of all these parts is somewhat critical so everything aligns and works properly. I took only the minimum amount from the valve chest mating surfaces to clean the rough casting. I wanted to keep the valve (initially) as far from the center line of the engine as possible. As it turned out this worked out well; if you build one of these engines I would highly recommend proceeding with caution at this stage.
You will probably notice that some of the pictures seem out of order; this is because I stuffed the original valve chest casting and had to request a new one from Roland
. The ports have a D shaped hole that connect the ports above and below the valve seat; well the first one on the exit side came out fine but when I did the inlet side I neglected to rotate the D 180 degrees and cut right into the valve seat. So I did things a little differently on the new casting as far as the order of operations. So some of the photos are from the first casting and some from the replacement.
Also the upper swing arm bracket was completed before I fitted the valve chest to the cylinder as you will see in a future post. I wasn’t sure just how everything was going to line up so there is a little jumping around; but in the end all is well (I think).
Here is the raw casting after a little cleanup and a trip through the blast cabinet.
Holding onto the valve guide I was able to satisfactorily center up the casting in my little 3 jaw chuck. Working carefully the chucking boss was faced and center drilled.
The chucking boss is finished turned and the top of the casting faced off.
The casting is flipped around and the valve guide rough turned as well as the bottom being faced off.
In the mill vice the casting is squared with the side surfaces which will not be machined.
[/img]http://listerengine.com/coppermine/albums/userpics/10012/Valve_Chest_006.jpg[/img]
The gasket surface is cleaned up (just barely).
Using the center-line as the datum the sides are machined to match the boss on the cylinder. The mounting holes were also drilled at this time.
Back in the lathe the valve guide is turned to size and length; I removed quite a bit of material from the bottom so the chest would match its mounting boss on the cylinder.
Flipped around the chucking lug was removed and the boring and threading done for the valve chamber and plug. Most of the chucking lug was removed in the band saw first.
The print said to spot face the nut locations but I prefer the look of having the whole surfaced milled so that is how I finished the mounting flanges.
Here the water jacket ports are being faced off.
Spot drilled.
Drilled.
And taped 1/16-27 NPT.
Finished; same for the other side.
The valve guide is indicated in.
The valve guide is drilled and reamed.
The exhaust port is taped ¼” NPT.
I still need to do a little hand work and cut the valve seat but for the most part the valve chest is complete.
Thanks for checking in.
Dave