Werowance attempts Upshur Vertical Single

[werowance]

Well I’m happy to report the second cam was found an I treated it like finding gold. I hope this pos works ok as it’s from my iPad and I can barely read the print. But yayyyy. Canm located!

 

[werowance]

Right up against the trash bin in the floor sweep compound right up a against it

 

[awake]

Yay! Now you can come and find some of misplaced parts in my shop!

 

[werowance]

now you know we are supposed to be social distancing..... (not playing down the real importance of that)

 

[werowance]

actually looking at your profile widget you are probably not that far from me. I'm in VA, near Bristol. not that it means we are really close but one state below me is all.

 

[awake]

According to Google Maps, it looks like you are right in the "corner" of Virginia, right next to NC and TN. Yes, not all that far - about 4-5 hours from here, but we get up to Boone, NC from time to time, and it looks to be only 1.5 hours from there. Maybe once this pandemic is over we can plan a western NC/VA model engine fest!

 

[werowance]

just some pictures. really not much new yet

 

[werowance]

still working on spacers, I cut them close then finish them with sand paper on a marble tile to the right thickness. gear to bearing spacer is where it needs to be (hopefully) and the gear to first cam is still a little thick in the pictures below. and after I took the pictures I realized I probably should have waited until I could shim the crank shaft and its gear into the proper position before I did the cam. oh well I will adjust if necessary (wont locktight anything until all parts are mocked up) I cant shim the crank until I have a rod and piston. I think it will be ok as there will be some wiggle room to move the gear on the crank back or fourth if need be.

on the points cam, I wish I had put just a little lip on it to keep it from running against the outer race of the ball bearing on the outside. making a shim washer that thin is difficult and usually requires loosing a little skin from my finger tip on sandpaper / laping plate to thin a brass washer down

 

[awake]

Weworance,

What is the thickness of the cam shaft gear? It looks like the cams and tappets are around twice as wide as the gear, right? I'm asking because I've been playing around with a design, and wondered how wide the cams should be.

 

[Brian Rupnow]

The cam only needs to be as wide as the tappet. However, if you are attaching the cam to the shaft with a set screw, then your cam will need a round hub about 1/4" long on one side to accept the set screws.

 

[awake]

Okay, that confirms what I was thinking. Thanks!

 

[werowance]

plans say .230 wide for the cams as typical. I did go just a little wider just because I could and there was clearance. the gear is .125 wide.
thanks

 

[awake]

Ah, very helpful, thanks. I was thinking maybe the gear was .25" wide, and the cams would then be in the vicinity of .5" wide - and that was seeming to get rather larger than what I had in mind for the design I'm playing with!

 

[werowance]

spent last night cutting through a slab of 2024 aluminum to use for the piston rod and just started turning a piston as well. took a while to get through that slab of 2024 on the band saw.

 

[werowance]

more work on the piston. will do the final part off after I have the wrist pin hole drilled and reamed. saw on another post the other day on this forum about leaving the extra on to make the piston easier to hold for that drill procedure. should make it much easier to hold in my collet chuck that on my Webster where I barely had enough protruding from the chuck to clear for the reamer. I plan on making (attempting to make) my own rings so they will be lapped to fit the grooves instead of me cutting the grooves to fit store bought rings.

 

[werowance]

managed to cross drill and ream last night is all

 

[awake]

"... is all" -- but that is far more than I have managed for the past several nights! Continuing to follow with interest!

 

[Brian Rupnow]

The second counterbore in (the one in the same location as the wrist pin) is supposed to be a slot, not a round counterbore. Did you do something wrong or am I just seeing it wrong?---Brian

 

[werowance]

i thought the same thing at first but nope. the Upshur is just 2 holes bored at different diameters large enough to clear the rod according to the drawings

 

[werowance]

doesn't even use set screws to hold the wrist pin. just rounds over the ends of the wrist pin with an inserted brass or aluminum plug