Swifty's build of Rupnow engine.

[Swifty]

Have recently bought some oak to make a base for the engine and a box to hide the electrical gear.

Important note to self: mitre gears eat earth wires when they come too close.:wall:

Paul.

 

[gus]

Have recently bought some oak to make a base for the engine and a box to hide the electrical gear.

Important note to self: mitre gears eat earth wires when they come too close.:wall:

Paul.

Hi Paul,

Thanks for the advance warning. The earth and contact point wire will be harnessed and strapped down to mini rail on the cam gear side.
At last I see light at the end of the tunnel..

Bought a 1'' thick cheapy China Plywood for the base. Oak or good tropical hardwood cost a bomb here.

 

[Swifty]

I decided that I better get busy and make the base to mount the engine on, but first off I thought that I would make a box to hide the electrics.

Before I start, let me fill you in on this, the Woolworth conglomeration is busy building Masters hardware stores around the country, about a year ago they opened one near me, by all accounts they are struggling to make any money, but one good thing is that they stock dressed timber in 6mm and 8mm (and others) thicknesses, with varying widths in Oak, Poplar and I think, Cedar. All very nice sizes and material for the home hobbyist.

I purchased some 6mm x 44mm and some 6mm x 90mm oak. The 44mm is for the sides and the 90 is for the top and bottom. First decision was how to join the sides together, I decided that I would try making finger joins, at least that is what I think they are called.

The first picture shows the 4 sides already machined.



Now I step backwards a bit and I will show you how I machined them in the next picture. I sandwiched the sides between a couple of bits of scrap chipboard and used a 6mm end mill to mill the slots. The bits of scrap are to prevent any chipping of the oak.



Next I applied some PVA glue to the joins and tapped everything together, I also glued on a top and bottom piece, and clamped it up overnight.



After trimming the top and bottom, this left me with an enclosed box.



Next thing to do was cut all the way around to form a lid. I set up a slitting saw in the mill, with a parallel clamped to the table as a backstop. By holding the box down on the table and against the parallel, I fed the box against the saw by hand, cutting through all 4 sides.



On the inside of the lid, I glued some thin strips at each end to act as locators to align with the box. (Sorry, no picture) After a bit of work with some sandpaper, and several applications of some cabinetmakers wax, I now have a box to house the electrics. I will machine some slots in the box later to allow the wires to come out. I did not want to mess around with hinges and catches, that's why I used locators in the lid. I have ordered some rare earth magnets that I will embed in the sides to keep the lid on.

Paul.

 

[Swifty]

I cut a piece of oak to length for the base, routed a chamfer around the top edges, gave it a good sand, and applied several coats of cabinetmakers wax. The electrical box was screwed on in a couple of places, I also replaced the earth wire that was previously chewed by the bevel gears, and I needed a longer spark plug wire. I happened to have some silicon wire that I had been saving for about 20 years, although white instead of black, I used this for the replacement HT wire. Apart from making a small clamp to hold down the HT wire, the engine now joins other finished projects. I will post a video of it running as soon as I get my hands on a decent video camera.






Thanks everyone for following along.

Paul.

 

[Brian Rupnow]

Well Paul---You may not have the first Rupnow engine ever built, but I can say that you definitely have the prettiest!!! And you just got to love a guy that does beautiful woodwork with his machinists tools!!!

 

[Swifty]

Thanks Brian, I think that the lid will be a perfect place to have a plaque that says "Rupnow Hit and Miss Engine 2013", will have to look in to it.

Paul.

 

[Brian Rupnow]

I like the look of your gas tank better than mine. I hunted all over to find my gas tank, which is the fuel tank off an old Coleman gas iron, thinking it would be "period perfect" for a hit and miss engine. I've had it on two engines now, and I don't really like the look of it near as much as a simple cylindrical tank like yours.---Brian

 

[Path]

Paul ..

Your H&M ... well simple put ... is beautifully done.
It's worthy of showing off on your living room mantel for all to see.

Hope I can do something as good.

Looking forward to your video.

Pat H.

 

[Swifty]

Brian, when I made the fuel tank, I only had the 1" copper pipe, which at the time I thought was a bit small. However I am happy with the size, although I could probably fitted in up to 1 1/2" dia in the position that I have the tank.

Have you ever thought about using some square or rectangular thin walled tubing, it would probably only be available in steel. The biggest problem that I see with steel is when it's soldered / welded you will have a fair bit of scale to get rid of. I may give it a go sometime just to try it out.

Pat, thanks for your comments. My wife and I share a study and we both have glass fronted cabinets, my wife has already said that she wants the engine in her cabinet, although that's what she said about my last beam engine, and that's in my cabinet.

Paul.

 

[Swifty]

Brian, I must comment on your one way valve, it's works extremely well, the fuel refuses to flow back into the tank even after several days.

Paul.

 

[Path]

Paul,

I noticed that you added a spring on the Push Rod Guide that attaches to the Push Rod.
I guess that helps the Push Rod stay in contact with the Cam Gear?
What was it doing to compel you to add the spring?
I looked in your posts but couldn't find a comments about that.

Also noticed what looks like two oil holes in the Push Rod Guide .. makes it easier to oil?

Finally (for now) did you use the locating pins? Doesn't look like they are in place. Maybe later?

I really like your gas tank ... mind if I use your design?

Thanks,


Pat H

 

[Swifty]

Pat, maybe I made the pushrod guide a bit too neat fitting, I found that the valve spring was not always pushing it back fully and the valve not seating properly, that's when I decided to add the extra spring, I probably could have fixed the problem by using a bigger valve spring. I also liked the idea of having the cam in constant contact with the bearing on the pushrod.

I ended up making a larger push rod after the original bent, and I added the 2 oil holes to aid lubricating the rod.

Please go ahead and copy my gas tank design, I went out this morning and picked up a box of assorted O rings as I needed one for under the tank breather screw to seal it off when not running.

I haven't bothered finishing off the dowel pin holes at this stage as I have had no problem reassembling the parts.

Paul.

 

[gus]

A MasterPiece done by a Master Craftsman. The Carpentry Work is very good too.
The base and box also done my a Master Carpenter. Did you do carpentry in school too.
Will carbon copy this too if I can buy Oak.If not,will buy teak or Chengai.

 

[Swifty]

Hi Gus, at school I did woodwork and metalwork, although the projects we made were very basic. I enjoy working with wood, but I am certainly no cabinetmaker. The main problem I have with wood is finishing the surfaces with lacquer, that's why I settled on using cabinetmakers wax. Will have to be careful that I don't spill too much fuel on it as it may take the wax off.

Paul.

 

[Smithers]

Nice work Paul, beautiful metal and woodworking skills.

Andrew

 

[Swifty]

Thanks Andrew, looking forward to seeing yours progress.

Paul.

 

[Swifty]

Well, I finally managed to borrow a decent camera to video the engine, of course the other problem that I had was trying to convert the video to a suitable format that I could upload, but all sorted after a few hours. No commentary, just the engine running, the mitre gears tend to make a bit of noise.



Paul.

 

[Brian Rupnow]

Swifty--Its a beautiful thing!!!---Brian

 

[Cogsy]

Sounds awesome. I quite like the whine from the gears.

 

[Path]

Fantastic ... looks and runs great!



Pat H