Swifty's build of Rupnow engine.

[canadianhorsepower]

Hi Brian, I recalled your problem with the lever, I plan to make a hardened silver steel pad to pin in that area if mine wears a lot.

Paul.

Brian and Paul---- even If not to active lately my Idea to solve this was to shorten the pushing pin to the proper length needed do disengage the push
rod what do you think

 

[Swifty]

Hi Luc, I will check out the pin length carefully when I set mine up.

Paul.

 

[canadianhorsepower]

Hi Luc, I will check out the pin length carefully when I set mine up.

Paul.

on mine the plan is to lift the ball to the max
engage the pushrod pin to lock it, leave a 30th clearance in between
I'll be using an over center spring on the detent to make sure it stays
engage even if the ball or not touching it:hDe:

 

[Swifty]

Still working away at the last pieces, the main problem at the moment is obtaining a spring that's suitable for the governor. The one I have is a bit too strong, even though I turned up some brass weights to try out. Can't get anything from the local hardware suppliers, so I will have to go to a spring maker and search through his stock.

I have started making a small fuel tank from some copper pipe, I would have liked a bigger diameter pipe but my next size up was too big. I don't know how the people who make copper boilers manage it, but my copper pipe sure sucks the heat away in a hurry when I try to silver solder the ends on. I suppose that I could have used lead solder, but have managed ok anyway.

I have also modified the head as per Brian's latest redesign.

Paul.

 

[Brian Rupnow]

Swifty--You may have missed it in my main post, but I found the 5/8" diameter brass balls to be too heavy, and had to swap them out for aluminum balls.---Brian

 

[Swifty]

Hi Brian, yes I saw that, my problem at the moment is getting a spring weak enough to allow the governor to work properly. I have aluminium as well as brass weights, all 5/8" dia. Will check out a spring maker this week.

Paul.

 

[ELM6061]

G'day Paul, If it is any help, I am pretty sure I have a few spare compression springs that are pretty light weight here at home. What size are you after exactly?

I did also have some stretch springs here, but no idea where they are now.

Eddie

 

[Swifty]

Hi Eddie, I need 3/8"OD, and about .020" wire dia.

Paul.

 

[gus]

Bought a box of assorted springs from the neighbourhood hardware store. The Webster Engine intake valve spring came from here.
The first spring was too strong and low speed idling was difficult to get.
Found a very weak spring and proven to be good for low speed idling.
Springs for the "Hit & Miss" would come from here. Backup would be make a spring machine to make springs as per engine drawing. Needless to say ,Gus has no experience making his own DIY Springs.

 

[Brian Rupnow]

Gus--Its fairly easy to wind your own tension springs from music wire (I use guitar springs). I have posted a couple of "how to" posts on the forum. Compression springs are a bit more difficult, and require the use of a spring winding fixture and an automatic carriage feed on the lathe as would be used for cutting threads.

 

[canadianhorsepower]

Hi Eddie, I need 3/8"OD, and about .020" wire dia.

Paul.

how long??

 

[petertha]

...it allows you to try different positions for the gear before committing to a fixed position. I plan to drill a shallow indent in the shaft to take the grub screw once I'm happy with the exhaust valve timing.
Paul.

Ive been wondering about different gear attachment methods related to cam timing gears. I understand the grub screw idea to position the gear or even alter it a bit. But once estblished, what is the best way to go about milling the corresponding underlying flat on the shaft to match that exact position when the gear is re-introduced to the shaft & the grub screw bottom mates to it? ie - the flat itself is tiny, so if was was off by a smidge, that might translate into a larger angle, especially related to cam/valve timing etc.

Nice build!

 

[Swifty]

Petertha, I intend to drill a shallow hole in the shaft the same diameter as the grub screw. I will do this once I'm happy with the valve timing, the grub screw will leave a big enough mark on the shaft to allow me to see where to drill the hole.

Luc, I think that the spring will be about 1 1/2" long, will have to experiment a bit.

Paul.

 

[gus]

Gus--Its fairly easy to wind your own tension springs from music wire (I use guitar springs). I have posted a couple of "how to" posts on the forum. Compression springs are a bit more difficult, and require the use of a spring winding fixture and an automatic carriage feed on the lathe as would be used for cutting threads.

Hi Brian,

Thanks.

Tubal Cain,UK( the real Tubal died some years back) wrote a book on how to make springs. Trying to find time to read it. Meanwhile I cheat with Kit boxes of assorted springs. Been stretching tension springs to use as compression springs.:hDe::hDe:
Valves done,lapped and installed with retainers. Push-rod guide done.
Now getting a good feeling of compression and vacuum.Viton Rings has yet to come in.
Now about to cut timing gears and cam. The Hit & Miss is stretching Gus's limited
machining skills. Good learning experience. Been fun. Scrapping parts is good learning experience too.

 

[Swifty]

Member Eddie, (ELM6061) dropped off some assorted springs this morning and I have put everything back together. I have had the engine running in hit and miss mode in short spurts, I still need to play around with the fuel as it tends to flood. I will finish the fuel tank next as this will get the fuel level below the carburettor which I think will help a lot.

I'm very happy with the electronic ignition, it's a great way to go.

Paul.

 

[Swifty]

My son called around after work and was keen to see the progress on the engine, so I put up the makeshift fuel tank again and ran it for him. I also played around with the spring tension on the governor while it was running. Things started to improve, so I decided to change over the aluminium weights to the brass one's and also changed the spring to a slightly stronger one. These changes allowed the engine to run for a longer time with the hit and miss cycle working well. I will be happy when I have the new fuel tank ready, as this will help a lot.

The video was taken again with my pocket camera, so it's not too good, but you will get he idea.



Paul.

 

[ELM6061]

G'day Paul, great to see the governor "spring" in action. Any idea what the RPM would be, and what you may be able to get it down to (Brian can probably answer the second part better)?
Roughly, at it's lowest RPM Brian, do you know how many misses to hits do you get?

Paul, how much more do you need to do to the fuel tank before it is also completed?

Eddie


Eddie

 

[Brian Rupnow]

I think mine is running at about 150 rpm. It goes thru 3 or 4 miss cycles. Wonderful job, Swifty. If you want the engine to go faster, try lighter balls on the governor.

 

[Swifty]

Eddie, I don't know how fast it is running, will check it out later. I would like to have it running as slow as possible. I probably have about a days work on the fuel tank, but the problem is finding the time.

Paul.

 

[Swifty]

Finished the fuel tank, it's made from 1" pipe, I would have liked it a bit bigger but it's all I had. I don't intend to run the engine for prolonged periods, so the fuel capacity should be enough. The only thing to make now are some brackets to attach it to the engine. The screw in the vent hole has a 2mm slot milled in the side to allow air to get in, and it also can't shake out as it's held captive by a pin.



Paul.