Author Topic: PMR #5 - as a fill in project  (Read 13508 times)

Offline Tennessee Whiskey

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Re: PMR #5 - as a fill in project
« Reply #135 on: June 29, 2018, 05:15:57 PM »
Now that I have been thinking about it, I think I used one of those 45 degree spotting, chamfering, milling cutters.

Cletus

Offline b.lindsey

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Re: PMR #5 - as a fill in project
« Reply #136 on: June 29, 2018, 09:22:33 PM »
Thanks guys, I think I will go the route of the chamfer/milling cutter.

Bent, when I did that through bore on the frame, I got close with a boring bar and finished it with a reamer which worked well for me, though not a sherline job at all. The fit with the crosshead is just what I was looking for, a nice slip ( though not sloppy at all) fit. I thought about broaching too but not sure the casting can take that much pressure and the broaches are pricey to say the least unless you make one.

Bill

Offline Craig DeShong

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Re: PMR #5 - as a fill in project
« Reply #137 on: June 30, 2018, 02:03:19 PM »
Good progress on both fronts Bill.  Glad to see retirement is affording you a little more shop time.
Craig

Offline b.lindsey

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Re: PMR #5 - as a fill in project
« Reply #138 on: June 30, 2018, 05:23:39 PM »
Thanks Craig. Retirement is agreeing with me well I must say ;D

Bill

Offline b.lindsey

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Re: PMR #5 - as a fill in project
« Reply #139 on: July 04, 2018, 03:01:34 PM »
A bit more done on the cylinder and valve in particular. After killing off the valve casting while milling the underside "D" pocket, I just remade it from bar stock. Apparently Cletus sent Bozo over my way  :lolb:

Anyway with the new valve made and the valve nut, things seem to fit well and slide nicely.

Bill

Online Kim

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Re: PMR #5 - as a fill in project
« Reply #140 on: July 04, 2018, 03:46:01 PM »
Sorry to hear about the untimely demise of the valve casting, Bill.  But it looks like you've got it sorted here and have a nice looking D-valve! 
Kim

Offline b.lindsey

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Re: PMR #5 - as a fill in project
« Reply #141 on: July 09, 2018, 01:06:27 AM »
Thanks Kim. Today's progress was the three pieces that make up the middle of the valve train. The first photo in the 3/16" square rod that rides in the frame. This was attempt two, as I had previously made a perfect one out of 1/4" stock rather than 3/16"....duh!!...read the print before machining. The second photo is the beginnings of the swivel part that will connect to the eccentric eventually ( as well as a shamelessly photo of mini mic who has been feeling outcast lately). The third picture shows all three parts and the last photo how they fit together and are positioned on the frame one the v grooves are cut.

Bill

Offline b.lindsey

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Re: PMR #5 - as a fill in project
« Reply #142 on: July 10, 2018, 01:07:47 PM »
Not much shop time yesterday but did manage to get the bearing caps and valve guide caps all separated from a single casting tree. Now to get them all cleaned up and machined down to size and mounting holes drilled, etc.

Bill

Offline J.L.

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Re: PMR #5 - as a fill in project
« Reply #143 on: July 10, 2018, 02:10:39 PM »
Hi Bill,
Following along closely. We are almost at the same spot in our builds.
You are making good progress.
John

Offline propforward

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Re: PMR #5 - as a fill in project
« Reply #144 on: July 10, 2018, 02:38:34 PM »
Hi Bill,

Looking great. I love your build logs - very informative and detailed - lots of good advice on technique to be gleaned here, much appreciated.

Stuart

Offline b.lindsey

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Re: PMR #5 - as a fill in project
« Reply #145 on: July 10, 2018, 04:01:58 PM »
Thanks guys, hope to have more to show later today.

Bill

Offline zeeprogrammer

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Re: PMR #5 - as a fill in project
« Reply #146 on: July 10, 2018, 05:37:26 PM »
Regarding that square part...is there a reason why it's square rather than round?
Carl (aka Zee) Will sometimes respond to 'hey' but never 'hey you'.
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Zee-Another Thread Trasher.

Offline Tennessee Whiskey

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Re: PMR #5 - as a fill in project
« Reply #147 on: July 10, 2018, 06:30:54 PM »
Looking great Bill. I was looking at my #5 yesterday and remembered those fiddly bits. You seem to be handling them with ease  :ThumbsUp:

Cletus

Online crueby

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Re: PMR #5 - as a fill in project
« Reply #148 on: July 10, 2018, 07:16:38 PM »
Regarding that square part...is there a reason why it's square rather than round?
The square rod keeps the pivots at the top and bottom lined up, since it goes through a square bushing. If it rotated, it would bind up the pivots. That lets them offset the eccentric from the valve. On other designs, the connection is via a bent rod rather than this way.

Offline b.lindsey

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Re: PMR #5 - as a fill in project
« Reply #149 on: July 14, 2018, 07:09:26 PM »
After a brief pause to head down to the beach for a few days to be with family, I got back and have finished up these four little bits. First was the bearing caps. After getting both milled to the proper width, I put then in the mill vise to drill for the oil hole (photo 1), and then the two mounting holes (photo 2). With these done it was on to the smaller caps for the valve rod. After milling one side of each casting flat, I was able to use that as a reference surface against the fixed vise jaw to locate and drill the clearance holes for eventual mounting to the base frame ( photos 3&4). This left very little to hold the part in the vise with for me lling down the other side so I took a scrap piece of aluminum and drilled/tapped two holes with the same center distance and then attached these with screws to hold then for miling to the final width (photos 5&6). The last photo shows all four parts completed.

Bill