Jim builds his second v-8
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Got a pair. Put some valves in just for fun. I'm trying to keep the valve stems short so the covers don't have to be too tall yet I need room for the springs, spring covers and the guide washer base needs room too. When ever I used c-clips for valve retainers I've recessed them in the cover to kinda trap them in. Notice I didn't do that here. Anyone had any experience with non-trapped c-clips popping off?
Hey George, NGK 1/4-32 plugs from Advance Auto Parts for $14 ea. a couple of years ago. They had to order them. It took a day.
Hey George, NGK 1/4-32 plugs from Advance Auto Parts for $14 ea. a couple of years ago. They had to order them. It took a day.
Regarding the plug price. I noticed I posted a couple of different prices. The truth is I don't actually remember what I paid other than the price was under $15 ea. I've bought lots of them, maybe 25 over the last few years.
Hey, I'm still working on the heads. Seems like itnever ends. Here's a picture showing a few valve guides. These were turned from 5/16 brass on my Sheldon w56 lathe.
Also shown are the springs I intend to use; 0.023 wire. I plan to cut them in half. Bought them off e-bay.
Need some spring cap too.
Didn't have the proper size bore for the caps so I cnc'd the bore. That helpe me control the depth too. Shown is the fixture I built to hold them while I pocketed them out. Worked well.
Also shown are the springs I intend to use; 0.023 wire. I plan to cut them in half. Bought them off e-bay.
Need some spring cap too.
Didn't have the proper size bore for the caps so I cnc'd the bore. That helpe me control the depth too. Shown is the fixture I built to hold them while I pocketed them out. Worked well.
This is a screen shot profile of my head plan. I could have printed a jpg image but the camera was handy so I just took a shot of the screen.
Here I'm making some rocker arms. I've got 8 holes so I'll have 8 rockers.
I'm going to have to drill and tap each rocker for a set screw for setting the valve lash. In this pic I'm fashioning a fixture to hold the rocker for the drilling operation.
Here I'm making some rocker arms. I've got 8 holes so I'll have 8 rockers.
I'm going to have to drill and tap each rocker for a set screw for setting the valve lash. In this pic I'm fashioning a fixture to hold the rocker for the drilling operation.
Very Cool! Does this engine have a name yet?
jpeter said:
Did I really say "messed up"?
I didn't call you names did I? Haahahaha!!!
I'll see you Wednesday. Also bought a 1/16 parting blade today.
Every v8 needs a cam. It was time to start that daunting project. After a period of time with pencil and paper stressing the few brain cells I've left I booted the computer and layed it out. The following picture is a screen shot of the cam with the lobes surfaced.
I next had to create some tool paths. Here's a second screen shot showing essentially the same view but showing tool paths for surfacing the lobes.
I next had to create some tool paths. Here's a second screen shot showing essentially the same view but showing tool paths for surfacing the lobes.
I find the cam is less likely to warp if I blank it out first. I like turning these kind of projects between centers but the cam is quit wimpy for that work so I chucked it in a collet. I'm using a 1/16 parting blade.
BTW, the collet chuck was a previous project. I made the nose piece from solid bar. I had some work involved getting it accurately tapered. During the project I bought a cheap tapered sleeve to convert into a nose piece but what I found was the one I was making was a better fit than the Chinese one. The drawbar, not shown or course, was made from a piece of 1 inch black iron pipe. This collet chuck is the greatest addition I ever made for my lathe.
I made the tool post too. It from Home Shop Machinist plans from a few years ago. It's an excellent design, works really well and was easy to build. Here's the cam getting blanked out from 3/8 round bar.
BTW, the collet chuck was a previous project. I made the nose piece from solid bar. I had some work involved getting it accurately tapered. During the project I bought a cheap tapered sleeve to convert into a nose piece but what I found was the one I was making was a better fit than the Chinese one. The drawbar, not shown or course, was made from a piece of 1 inch black iron pipe. This collet chuck is the greatest addition I ever made for my lathe.
I made the tool post too. It from Home Shop Machinist plans from a few years ago. It's an excellent design, works really well and was easy to build. Here's the cam getting blanked out from 3/8 round bar.
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Hi Jim,
Compliments for the build, looks very good! I hope in future to be able to generate 3D milling paths too, for now I do all in the 2D world.
I like your collet holder, and planning to make one myself too. About the drawbar, did you use any bearing on the end? In my idea a pressure bearing will make it a lot more easy to tighten the collet in the main spindle of the lathe. I am curious to learn about your experiance.
Keep the progress coming, its a pleasure to read.
Regards Jeroen
Compliments for the build, looks very good! I hope in future to be able to generate 3D milling paths too, for now I do all in the 2D world.
I like your collet holder, and planning to make one myself too. About the drawbar, did you use any bearing on the end? In my idea a pressure bearing will make it a lot more easy to tighten the collet in the main spindle of the lathe. I am curious to learn about your experiance.
Keep the progress coming, its a pleasure to read.
Regards Jeroen
For a bearing I used a brass coupling and two pieces of pipe. I locktited the threads. I could have used a steel coupling and brass washer. If I was to do it again I'd use a brass bushing instead of a coupling cuz the pipes don't remain straight in the coupling giving me some out-of-balance condition from the wobble. I had a 5 or 6 inch pulley laying around I used for a hand wheel. I don't have any trouble tightening it up enough. Not including the collets I got under $10.00 into it. Runout is pretty small if I'm careful when I seat the nose piece. It's hard to measure runout cuz collets are not always perfect and chips get under stuff more than you'd think but if I'm really careful I can measure under a thou.
agmachado
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Hello Jim!
First, Is very cool your job and your design !!!
I have some doubts...
What CAD program do you use ?
What is the diameter of the intake and exhaust valves ?
The diameter of the cylinder is 3/8", correct ? That is less of the one centimeter... that is very crazy!
But very, very cool !!!
Thank you for share your project with us!
Alexandre
First, Is very cool your job and your design !!!
I have some doubts...
What CAD program do you use ?
What is the diameter of the intake and exhaust valves ?
The diameter of the cylinder is 3/8", correct ? That is less of the one centimeter... that is very crazy!
But very, very cool !!!Thank you for share your project with us!
Alexandre
2CYL4STROKE
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Hi Jim
I see that you using mastercam I have X2 Mr2 also
Jani
I see that you using mastercam I have X2 Mr2 also
Jani
This engine is a little bigger than 3/8 bore. Its a square engine 3/4 inch bore and 3/4 stroke. The cylinders are 1.0625 inches apart and the block is going to be made from 2.5 inch square aluminum. The block length is going to be slightly less than 5 inches. Regarding the valves, they mic out at 0.270.
Back to work on the cam. I clamped a block on the mill table, then milled a groove along the x axis for a saddle for mounting the cam blank. Then, I drilled the cam blank at the 5 bearing sites for 4-40 screws to bolt the blank down. I find it important to hold the blank straight while I'm machining it. These bolts and holes also index it when I do the other side. To machine the bottom half I just unbolt it, rotate it a half turn and bolt it back down. I don't expect the holes to effect the bearings much.
