Werowance attempts Upshur Vertical Single

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well smacking my forehead and shaking my head in disbeliefe of my blind ignorance. I'm going to say you meant post 249 but yeah, the plans sure enough plainly state .244. I hate when I ask and do stupid things like that.

but I really do appreciate the help. cant wait to get back to the shop and start laying it all out. hopefully there will be enough room to drill those radius without breaking through the sides but if not I will clamp some of the cutoff leftovers of the same thickness so when I do the drill it wont walk off center on me.

thank you until you are paid better as my mom used to say.
 
yesterday I received my points contacts as well as a 1/4 - 32 spark plug from the same place. ill have to say that plug is a lot smaller that a cm6 plug like I used in the Webster. I wont be able to use a regular spark plug cable like I did with the cm6 either. thought about enlarging the port for a cm6 but I kind of like the look of that little bitty plug so I'm going go with that since that's what the plans called for anyway. a US penny just for size reference
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That number is a "resultant". It is actually a "result" of using hard, solid numbers and a "true" 1.75 degrees. If you look at the original drawing it says "about 1.75 degrees". "Hard" numbers are given numbers that I arbitrarily use to develop the geometry.
I saw that it came from the different angle because of the note where you explained it. My question was that the dimension appears to be 1/4" to the left of the of where the other width is stated to be 0.359".

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On the original drawing and on my drawing also, that dimensions is taken at the point where the side of the con rod begins to transition into the radius.
 
just double checking before I clamp on some extra material and drill these holes for the radi that what I have circled in red is truly the center mark for the drill? the reason I ask is I recall having a devil of a time finding the center mark for the radi on the Webster engine on the support frame because the angle was not an exact 90deg more of a 60 deg angle and thus my center mark was not coming out right because I was not taking that into consideration.

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finally managed to get a rod made. third attempt and its not perfect either. after a test install I found that the wider than plans called for cam lobes are likely going to interfere, Ill be able to say for sure after I get a wrist pin made for the piston and can do a trial assembly. but oh well if it does ill then them down to per plan specs and re do my spacers. I'm glad I hadn't lock tighted the lobes in place yet.

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not very much progress lately but I did manage to get the wrist pin made with brass insert tips on both sides. hope to do a mock up assembly now that I have the wrist pin and verify if the rod really is going to hit the cams or not.

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the wrist pin is center drilled all the way through. then 2 pieces of brass round stock is turned down to match the size of the wrist pin, then a little tit is cut on the tip of the brass to fit the drill hole. it is pressed in with lock tight. plans said aluminum, brass or copper would work, plans also said an aluminum rivet would work well as well.

this piston has no retaining method of holding it in place like the Webster. short of lock tight when you assemble it so the brass tips are to prevent cylinder wall scoring in the event the lock tight fails and the pin moves to one side or the other.
 
maybe it was in the written portion he says copper or maybe I just dreamed that up or something. at any rate drawing portion says alum or brass. doesn't mention copper so strike that one


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That's sort of what I was envisioning. Take a small piece of brass, turn it down to a pin, then turn it around and use the pin to hold it while gently making a dome on the end. Drilling along the length of the wrist pin is an easy job.
 
well, how I did it was press and lock tight the over length (longer than need be)brass pieces with the tits on them in the steel wrist pin. then after the loctight had time to dry I chucked the wrist pin in and faced the brass off down to the proper size and thought about using a form tool to dome it, even my ball turner came to mind, but in the end it was such a thin piece I just used a file and hand formed the dome shape to it. polished with a little fine grit sand paper and steel wool
 
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HI
PTFE used to be used for buttons in model aircraft engines, probably because most had hard chrome liners, still may be of use in builds such as this.
 
I’m wating for these for same job and so cheep
 

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so not much progress happening. i have been working through clearance issues with the piston rod. 1. it hits the brass spacer between the two cam lobes (spacer not part of the drawings) so i am making a new spacer that is super thin walled, also thinning the cams down to close to drawing thickness as it hit those as well. surface plate and sand paper to do that. i want the spacers just to make it easier to stack everything up. the spacer blank is so thin walled i pushed the cam shaft into it to keep it from colapsing when thinning it down 2. then the side of the rod is hitting the bottom of the cylinder wall. to remedy that i spent hours filing and sanding, test fitting and repeat. it now clears like it should. 3. on the tappet guides. plans say to locktite them in place but since my top plate is bronze and the guides are brass would it be better to solder them in place?


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I wouldn't take a chance on putting more heat into the top plate. There is no real loading on the tappet guides. I would use Loctite.---Brian
 
werowance !
I think it has no effect on the cam lobe, if it is only partially cut or shortened by 0.5 or 1 mm

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If you are sure everything is ok, you can solder.


Mihn Thanh, i actually did thin or "cut" the cams as you show. they were wider than per plans anyway so what i did was surface plate sand them down thinner like you show the cut. i just sanded instead of cut. started out with 220 grit then on up to 800 grit to get rid of the side marks that no one would have seen anyway. now that brass spacer in between the 2 cams needs to be longer and also smaller diamater because the rod actually strikes that as well.

thanks for the suggestion though.
 

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