Werowance attempts Upshur Vertical Single

[werowance]

oh I get what your saying. essentially you are milling / squaring the large piece and the small cap piece edge at the same time thus its matched. now what I was going to do is one at a time mill the ends flat, then surface plate them just slightly to remove the mill marks but I'm thinking your idea might work better. at the least it would mean milling the 2 parts at the same time thus saving time.

 

[werowance]

Glad you said that - this lost me several posts ago. I need a picture of what the finished one looks like. Does two part mean that it's split at the crankshaft?

yep, split at the crank since the crank shaft is built up the only way to get a rod on it for it to be split. like a briggs and Stratton lawn mower engine would be.

 

[wthomas]

tjmatx is right about the folding over. If you do it and the mill head is off one degree it will not matter as when you fold it back down
the angles match. The only thing I would do different is I would not drill clearance in the cap. I would ream the cap to just .001" or .002"
over the bolt size at the same time I drilled and tapped the rod. This should give an exact match of bolt holes.

 

[werowance]

Last night i got the stock cut down and squared in the vice to drill and tap the 2-56 holes and evidently the shop gremlins hid my pack of 2-56 taps after i finished building the webster engine. them little buggers. that pack also had my #50 drill for the tap as well. hopefully a local supply place will have some i can pick up today if i am lucky, but i stopped after i spot drilled for the first screw since i didnt have the proper drill or tap for it.

also the plans say to use a shcs for the caps which i dont have in 2-56 but i do have 2-56 threaded rod. which makes me wonder if studs would be better for the rod cap vs shcs?

 

[werowance]

oh, and on top of the question about doing studs instead of shcs for the cap screws, i did a little work on the homeade points for the engine. instead of mounting premade auto points from the car parts store this engine has you make your own - which is something i want to try instead of mounting pre bought points. so the plans say to take the points contacts out of pre purchased points and solder them into the homeade points assembly.

so a few questions on that.
1. do they make just the contactors (for sale) so that i wouldnt have to remove them from pre-made points, if so where to look or whats a better search term than just "points"
2. arent the contacts just tungsten steel? could a piece of tungsten steel rod be purchased easily and turned down to correct size using carbide tooling? (i have no idea how hard tungsten is or anything here)
3. if i can just buy a piece of tungsten would there be any heat treating or anything needed here after cutting to size?

 

[awake]

Weworance, I'll take a stab at the questions you raised, but please note that I am answering based on what I have read, not what I have personally done.

As I understand it, the contacts are indeed simply tungsten. According to one book, they are available for purchase ... but if so, I have no idea where. I had thought about, if I ever try to make my own points, getting a 1/8" TIG electrode and cutting it to size.

As far as machining the tungsten, I don't think carbide will cut it (if you will forgive the pun). You can grind a TIG electrode using an aluminum oxide wheel, but not quickly; diamond is the "correct" choice. If I were to attempt this, I would think about getting a thin diamond cutoff wheel to cut it, and then hone it to size on a diamond "stone."

I don't think there is any heat treatment needed (or even possible??). The book that I referenced above talks about silver-soldering the tungsten in place.

 

[tjmatx]

Interesting: my plans show 4-40 screws for the connecting rod cap. You might want to consider those if it's not too late.

I got the plans from the Upshur site about a year ago.

 

[Brian Rupnow]

It won't make any difference if you use socket head capscrews or studs and nuts. Either will work fine. As far as ignition is concerned--I made up a set of points and it gave intermittent results. After screwing around for a whole day, I used automotive points and the engine ran immediately.---Brian

 

[werowance]

Interesting: my plans show 4-40 screws for the connecting rod cap. You might want to consider those if it's not too late.

I got the plans from the Upshur site about a year ago.

that's interesting, I double checked mine and its 2-56 with a smaller diameter or width of rod as well as shorter. I got my plans emailed to me from some of his family as the site is and was down. but he shared them with me for free however I did make a paypal donation to him for his trouble.

was yours the vertical or the horizontile farm engine model?

your drawings are dated 1977 but mine are dated 1996. with the smaller width as well as how close the hole already is to the edge I don't think 4-40 will work and I already started the drill

 

[werowance]

and I take that back, UpshurEngineWorks.com is back up and running. wasn't a few weeks ago when someone else was asking me about it.

 

[Brian Rupnow]

Werowance--I just checked---The head of a #4-40 shcs is 0.180" diameter. The width of the narrow part of your con rod is .312-(.047+.047)=0.218. Going in the other direction, 0.330-.244=.086" which is very very close to 1/2 the diameter of a #4 shcs. A #2-56 thread is smaller than a #4-40 shcs, so you should be able to redrill the holes and use a #4-40 shcs. the head doesn't have to be counterbored.

 

[werowance]

ok, sounds like a plan. ill shoot for 4-40 threads. worse case ill turn the part around and try again from the other end if its to wide.

and one more thing. and I know I ask this a lot. but I get it wrong a lot. if it calls for a .09 radius then I need to use a .18 drill (#15) correct? and offset by .09 up and left to mark for center punch so to speak. right?

 

[tjmatx]

To be honest... on things like the general shape of the rod, especially the shaft, I didn't worry much about the plans specs. I just kind of winged it and used my Harbor Freight 1" belt sander to shape it. Part of the reason for that is I don't have a lot of specialized tools that would help, like a rotary table. One thing I noticed about these plans is he doesn't have a notation for tolerances, or maybe I missed it. It seems like there are some places where he specifies down to 100th or 1000th when it doesn't really matter a lot except for beautification. Example is the valve seat cutting tool.

 

[Brian Rupnow]

Yes, your calculation should put the radius where it needs to be. Tjmatx---On the issue of tolerances--there is a set formula for tolerances, and in general, they are a pain in the arse. On something like one of these small engines, there are probably only 5 or 6 dimensions that really need to be toleranced to make the engine work correctly. People who design hobby engines assume that anyone clever enough to build their own engines will know which dimensions should be held to very close tolerances and which dimensions are 'open', meaning they are +/- .030". I make plan sets all the time, and I just set my drawing software to dimension to three decimal places. ---Brian

 

[fabricator]

It is actually completely against any known laws of physics how a small part can gain enough energy from a short fall to roll under the exact center of the nearest most inaccessible piece of heavy machinery.

 

[tjmatx]

Brian. Good to know and makes a lot of sense.

 

[Mow]

that's interesting, I double checked mine and its 2-56 with a smaller diameter or width of rod as well as shorter. I got my plans emailed to me from some of his family as the site is and was down. but he shared them with me for free however I did make a paypal donation to him for his trouble.

was yours the vertical or the horizontile farm engine model?

your drawings are dated 1977 but mine are dated 1996. with the smaller width as well as how close the hole already is to the edge I don't think 4-40 will work and I already started the drill

The Farm Engine uses the 4-40 cap screws and my plans are dated 1977 but the Vertical uses 2-56 cap screws and the plans are dated 1996.

 

[werowance]

It is actually completely against any known laws of physics how a small part can gain enough energy from a short fall to roll under the exact center of the nearest most inaccessible piece of heavy machinery.

well put. it is amazing how that always seems to be the case

 

[rsholl]

Individual Tungsten points are available here: S/S Machine & Engineering, LLC

Left hand column, first item listed in "NON CDI IGNITION SYSTEMS"

 

[werowance]

Individual Tungsten points are available here: S/S Machine & Engineering, LLC

Left hand column, first item listed in "NON CDI IGNITION SYSTEMS"

Thank you for that. I just ordered the contacts as well as a spark plug for them.