Parsell & Weed Horizontal IC Engine

[Kim]

Very nice Bill. I'm enjoying seeing your setups and how you do this on the Sherline.  Very impressive!
Kim

[b.lindsey]

Thanks Kim!  I got a few more fiddly bits done today, but not set-up or machining shots. I got the rocker arm made with a few dimensional changes from the plans to better match the cylinder head geometry, the rocker arm pin, and the tappet. I would show these assembled, but I loaned my only 4-40 tap to my senior design group at school and won't have access to it till tomorrow. I need to order a couple so I have more than just the one. Photo 2 is where I had screwed the pivot pin into a 4-40 tapped hole I had on hand in a piece of brass just to check that the rocker arm swivels as it should.

A few pictures of todays parts are attached below.

Bill

[zeeprogrammer]

Sure looks like you're moving a bit faster. A lot of work done.
Good looking parts! 

And well trimmed nails! 

[b.lindsey]

Thanks Zee. I spent all day on the head yesterday and 3 piddly little parts today but it's still progress, It dawned on me today I still have to put the hole for the spark plug in the head too. But I will take what time I can get in the shop. It's all good.

Bill

[Dave Otto]

Hey Bill

I enjoyed seeing the updates on your engine this weekend. The head turned out very nice as well as the rocker arm.

Great progress!
Dave

[b.lindsey]

Thanks Dave, It was nice to get some shop time in and make a little progress this weekend too!!

Bill

[Don1966]

Great updates Bill, your really getting into this engine bud...... Glad the sander works for you and the more you use it, the more ways you will figure out how to us it...... 

 
Don

[joe d]

Looking good, Bill.

Anticipating the next installment.....

Joe

[Flyboy Jim]

Thanks Zee. I spent all day on the head yesterday and 3 piddly little parts today but it's still progress, It dawned on me today I still have to put the hole for the spark plug in the head too. But I will take what time I can get in the shop. It's all good.

Bill

Uh Bill.....................The boaters is the group are going to wonder how you could spend "all day on the head yesterday" and still be able to get all this work done? 

I'm really impressed with the rocker arm and still trying to figure out how you did it.

Jim

[fumopuc]

Hi Bill, I am still following along. A nice rocker arm and a well done cylinder head.

[b.lindsey]

Thanks for looking in Jim and Achim. Jim the rocker arm was pretty simple and made from a piece of 1/4" square brass. As I noted earlier one aspect of the head geometry seemed off to me. The plans call for the top of the rocker arm bracket to be .110 below the centerline of the valve stem hole. I though I had this dead on as I had oriented the valve stem holes vertically, found the center with an edge finder and then used a 3/16" end mill along the top of the rocker arm bracket. That should have put the surface at .094" below the valve opening, so I stepped close by .016 to take another pass which should have put it at the .110" dimension. From there I cleaned up the underside as well. After looking at it afterward it didn't appear to be .110 at all. All I can figure is that may have only moved the edge finder .050" instead of .100 to locate the center of the valve stem opening thus putting the rocker arm bracket .050 higher than called for.  Not wanting to redo the entire head, I just decided to "adjust" the "pads" on either end of the rocker arm by lowering them relative to the mounting surface. Ideally the rocker arm should be symmetrical about the centerline. It looks ok on the valve stem end now, won't know on the tappet end until I get a bit further along. Worst case is that I may have to remake the rocker arm again, but that is far less demanding than remaking the whole head.

Bill

[Mosey]

Bill,
Did you make that sweet slotted screw? The large one?
Wow!
Mosey

[b.lindsey]

Mosey, yes I made the screw from drill rod. The head is only .203" diameter though, 4-40 threads so not a real giant among screws

Bill

[Flyboy Jim]

Thanks for looking in Jim and Achim. Jim the rocker arm was pretty simple and made from a piece of 1/4" square brass. As I noted earlier one aspect of the head geometry seemed off to me. The plans call for the top of the rocker arm bracket to be .110 below the centerline of the valve stem hole. I though I had this dead on as I had oriented the valve stem holes vertically, found the center with an edge finder and then used a 3/16" end mill along the top of the rocker arm bracket. That should have put the surface at .094" below the valve opening, so I stepped close by .016 to take another pass which should have put it at the .110" dimension. From there I cleaned up the underside as well. After looking at it afterward it didn't appear to be .110 at all. All I can figure is that may have only moved the edge finder .050" instead of .110 to locage the center of the valve stem opening thus putting the rocker arm bracket .050 higher than called for.  Not wanting to redo the entire head, I just decided to "adjust" the "pads" on either end of the rocker arm by lowering them relative to the mounting surface. Ideally the rocker arm should be symmetrical about the centerline. It looks ok on the valve stem end now, won't know on the tappet end until I get a bit further along. Worst case is that I may have to remake the rocker arm again, but that is far less demanding than remaking the whole head.

Bill

Thanks for the explanation Bill. I'll be looking forward to , as they say, "the rest of the story" as you get further along. 

Jim

[b.lindsey]

Before I can finally settle things on the rocker arm, I need to make the front and back pushrod guides that fit the square extension off of the cylinder collars. The 3D view of these is shown in the first two photos. Though some suitable pieces of bronze are supplied with he casting kit, I elected to cut a couple of pieces off a piece I had on hand. Tonight I got a start on the back pushrod guide by  milling the piece of bronze down to the overall dimensions required for the finished part (photo 3). Since two of the dimensions are really close I oriented it correctly and sketched out the outline with a  sharpie just so I wouldn't do any further machining with the wrong orientation (photos 4 & 5). More on this and the other guide tomorrow and over the weekend.

Bill