Brian builds Atkinson Engine

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Brian Rupnow

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Here we go with the cam shaft stands. Those scallops out of the sides look pretty, but there is a fair amount of set up and machining involved in them. I am using one peice of bar and working from both ends.


 
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Don1966

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Hi Brian glad you are back, I hope your vacation was enjoyable with the grand kids. Your work looks great as always. I am still here interested and following your progress.

Don
 

Dan Rowe

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Brian,
I have always enjoyed your posts. Going on about who owns the site strikes me a bit like two fleas arguing over just who owns the dog. I hope to continue watching your builds.

Dan
 

Brian Rupnow

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I have seperated the two cam bearing stands from the original single peice of bar, squared up the cut ends and added the mitered corners. I just cut the required slot with a 3/8" diameter 2 flute endmill, and will add the tapped holes which go in the bottom of each slot before tearing down this set-up.

 

Brian Rupnow

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I picked up my four 5/16" dia. x 2.5" shoulder bolts this morning, and was pleased to find that when passed thru the four reamed holes in my cylinder support block that they lined up perfectly with the holes which I had drilled and tapped in my fixture last week before going away on holidays. This is what the set-up looks like at the moment.--I will post a few "in process" shots when its mounted in the lathe.----Brian
 

Brian Rupnow

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Well gentlemen---Here we are with the first radius cut full depth.--Very scary indeed, but its working great. I'm running at 300 RPM and backing the cross slide out 0.010" each pass. (Thats .020 off the diameter.) Now I will undo the bolts, flip the peice being cut end for end, and have at it again.

 

rhitee93

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Cool. I have to admit, that setup wold probably cause me to change my shorts :)
 

Brian Rupnow

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So-----There we have it.-No smashes--No dashes--No horrible crashes!!! I didn't notice when I took the pictures, but the threaded holes in the cylinder are visible.--It has to be rotated so that they align with a pair of matching holes in the newly finished peice. (which I haven't drilled yet.) Everything went well, but I really don't like machining with so many things whizzing around in front of me.--Actually, not in front of me---I stand off to one side out of the tangential line of fire!!!

 

rhitee93

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I'll applaud that just 'cause you got, ahem, lathe handles as big as church bells.
 

Don1966

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Awesome Brian, you are a true craftsman. One day I hope to be one, no time soon I am sure. Love your work.


Don
 

Brian Rupnow

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I finally got to the point yesterday when I actually had to spend some money for material. Jan Ridders calls for his base to be 170mm x 300mm x 10mm. I have seen videos of these engines and how poorly balanced they are---they want to jump around when running. I bought a peice of 8" x 3/4" x 12" aluminum for the base to keep it heavy. The metric conversion is about 6.7" x 11 3/4" x 3/8", so the closest I could buy in flatbar was 8" x 3/4". I also bought a peice of aluminum bar 3" x 1/2" x 18" long to make the two tall flywheel shaft supports from and a peice of 1" x 1/2" aluminum bar for miscellaneous parts. This cost a grand total of $45.00. I will know the full cost of bearings today---(Every revolving shaft runs on ball bearings)
 

Brian Rupnow

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This was a "bits and peices" kind of morning. I finished off the tie that bolts between the cam shaft supports and added the bushings for the valve push rods. I also made up the bushing for the pivot stand, as it was the same i.d. and o.d., just a bit longer. You can't see it, but I drilled and tapped the holes in the underside of the cam shaft stands that are used to bolt them to the main baseplate. If I work this afternoon, I have some serious flycutting to do.
 

Shopguy

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Great progress Brian
Very well done as always.
There's a project for someone, figure out how to balance one of these engines.
Regards
Ernie J
 

b.lindsey

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Brian this is looking great and one of my favorites of your build logs thus far. Glad you are sticking around too!!!

Bill
 

Brian Rupnow

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This is a big OUCH in the wallet!! The plans call for all ball bearings on the shafts, and I ordered them yesterday from Canadian Bearings.--I wanted to have at least one i.c. engine that is not constantly slinging oil all around as it operates. My previous two i.c. engines had open crankshafts with bushings, and to say they are messy little devils when running wouldn't be an understatement. ---On the other hand, bushings are dirt cheap. Any videos I have seen of this type of engine running shows that it is very unbalanced, and tends to "lurch" a bit (for lack of a better word) when running, so probably the ball bearings aren't a bad idea to cut down on friction.
 

b.lindsey

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Ouch is right Brian!!! Pricey little buggers.

Bill
 

Brian Rupnow

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Brian this is looking great and one of my favorites of your build logs thus far. Glad you are sticking around too!!!

Bill
Bill, I feel terrible about what has happened. I have never intended to make money from my engines, and since I had to develop the plans to build them for my own enjoyment, I felt that it was a good idea to "share" my plans with everyone on the forum. If someone else contrives to make money off plans I have submitted, its really no skin off me. Now everything is in dissaray, and a lot of my good friends seem to have left. I feel as if I have lost members of my extended family. I plan on staying here, but as I said before, with a "Wait and see" attitude. I have my own personal reasons for not wanting to migrate to another forum, and I'm glad to see you are still here. -----Brian
 
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