Arnold's little Rocking Engine

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arnoldb

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Well, the rocking engine fever bit - and I put myself a target to finish the little Rocker this weekend - start to finish.

Best of all, I actually finished it - and it runs! - making it my first completed and running engine! woohoo1

If you don't want to see the build pics - just go down - the finished engine and (hopefully)video is at the end.

I changed the bush and axle sizes, as well as all screws and threads to fit my available metric tools - so screws were made 3mm, bush ID 4 mm, bush OD 5mm, and out of sheer laziness (I guess), I made the shaft diameter for the flywheel 5.05 mm for a press-fit. Being a bit frugal, I opted to make the base from 2 pieces, rather than the single called for in the construction. The base plate is screwed to the mounting column using a 5mm countersunk screw.

I planned for an early start yesterday, but had to run out & get some drills I would need, as well as some piano wire - one hobby shop in Windhoek actually sells it. Bugger - as I'm leaving, the power goes out, so I just KNOW both the tool supplier for the drills and the hobby shop's systems will be down, as well as total chaos on our streets... So waited until the power cam back on 3 hours later for the run-around.

I started with a piece of brass from a longitudinal wedge of brass "pipe" - this had to be squared on all sides:
smaller-IMG_1117.JPG


As I don't have a suitable boring bar, and did not want to spend time making one, I drilled the required size hole (5.5mm) for some brass pipe I have right through the block, and parted off the cylinder head - to be soldered back on later:
smaller-IMG_1120.JPG


Then I bored the cylinder - I don't have a suitably sized reamer, so boring had to be spot on and smooth. The little boring bar I made last weekend did it's second job:
(Sorry - Photo's a bit fuzzy; my camera insists on picking up the swarf even in macro mode)
smaller-IMG_1122.JPG


Then I cross-drilled the block for the mounting hole and bush hole; then reamed the bush hole 5mm, but not all the way through the length of the reamer, so that the bush can be a press-fit.
smaller-IMG_1126.JPG


Now the part that I thought would be the most difficult - milling out the cylinder block on the vertical slide - my lathe's headstock bearings are not prime anymore, so milling is at best "risky". This turned out to be a bit bothersome, but I managed; though not a pretty or neat job. The most difficult job was still to come...
smaller-IMG_1127.JPG


Then I turned the little bush - reamed 4mm on the inside and 5mm dead on the outside. Turned out to be a nice press fit in the block. And YES - chasing this little bugger around the floor is no fun at all! :rant:
smaller-IMG_1130.JPG


Next up, I turned the little shaft and added it to the pile of junk:
smaller-IMG_1134.JPG


There I stopped yesterday evening - everything was grumbling for grub; my tummy was grumbling, the dogs kept under my feet, and Shrek the 'grey was hollering for cheese & potato - so the motley crew had to be fed & bed.

Actually I'm a lazy rotter, and one thing I like is my Sunday Morning sleep-in - no alarm clock! - so I only woke at 10:00 this morning and had to get a move on.
First thing, I turned the piston. The plans call for the crank and piston OD at the same diameter, so I turned it and finished it to required piston size - A check with the cylinder confirmed proper diameter after some final sanding work. Then I turned the connecting rod to size and parted the piston off at the required thickness (or - in this case - thinness ;) ):
smaller-IMG_1139.JPG


Still having the correctly sized piece of brass in the lathe, i just "touched" the end with the smallest center drill I have - then with dividers set to the correct size, marked a radius from the center hole for the crank pin. A quick transverse scratch from a toolbit in the cross-slide, and X marked the spot for the crank pin. Then I drilled clearance through the center and countersunk for a 3mm countersunk screw. - Another problem popped up here; I didn't have 3mm countersink screws (like I thought I had!) and it's head would have been too big anyway. Did the next best thing, and turned the head of a cheese-head 3mm screw down to the required size and counter-sink - problem solved.

Then I tuned the base and pillar from brass - nothing special; just plain turning (anyway, I was on a roll & forgot to take pictures :-[ )
More pieces added to the "junk pile" ;) :
smaller-IMG_1141.JPG


Next up was the flywheel - simple turning; I just faced it both sides and drilled & reamed a 5mm hole in the center. Then turned a mandrel with a nice shoulder on some 1/2" rod with a 4mm thread, and mounted the flywheel on that. Turned OD. Then on to the vertical slide & dividing head with chuck containing mandrel & flywheel - drilled the 6 holes. Next picture shows first hole drilled - the drill - chuck is in the headstock, an I didn't mid drilling through the washer either:
smaller-IMG_1142.JPG


Next some soldering needed to get done - I cleaned everything of all oil, then with an ear-bud coated in oil, I wiped the cylinder bore and around the bush/block. A ring of 60/40 solder around the bush, heat up the block/bush from underneath & it just flowed nicely in. For the cylinder head, I made a ring of solder and placed around the bore. Then put the cylinder head on top. Heated with the propane torch all-round, and when the cylinder head dropped down when the solder melted, just used a piece of wire to "accurately Rof} " locate it & let it cool down.
All soldered up:
smaller-IMG_1143.JPG

Oh yes, the brass pipe was just "pressed" into the cylinder head - 5.5mm hole, and 5.54 OD mm brass pipe - Persuasion tool (aka "hammer") worked well :)

Earlier on I said the most difficult job was still to come - it was! - The most difficult part of this engine was to get the darn 3mm screw screwed into the shaft while juggling the piston as well!

All Assembled:
smaller-IMG_1144.JPG

and
smaller-IMG_1145.JPG


And here it is running:
http://www.nam-engineering.com/pics/steam2/MVI_1146.AVI

This is my very first completed working engine, so some very special thanks are in order:

To my Dad who gave me the Myford, and a LOT of life skills - THANKS DAD!!!
Marv, THANKS for guidance, inspiration, motivation and a whole hog of maths - I REALLY appreciate it.
Rick, This is a great forum you started - Thanks a LOT!
And last, but definitely not least, to all the great members of this forum; long-time and new - for your valued input, comments and banter - Thanks Guys & Gals!

Kind Regards, Arnold
 
Good goin man. I still need to finish mine but was doing two at once well the weekend aint over yet but not exactly motivated at the moment.
Tin
 
Nice build, Arnold. Runs good and sounds good, too!

Chuck
 
What a neat little engine! Ticks right along, too.
A great project for the weekend, (or the week if were me building it).
Nice job, Arnold. Looking good.
 
arnoldb said:
Best of all, I actually finished it - and it runs! - making it my first completed and running engine!

Congratulations Arnold! 1st engine! Great job.
Great post too. You can really feel your excitement.
Thank you.
 
Nice work, nice build photos. :bow: I think I'm hooked.
 
Arnold,

Congratulations on your 1st runner. :bow: :bow: :bow:

Very nice - Now the engine building bug is in your bloodstream, there is no known cure. ;) ;)

Best Regards
Bob
 
Tin, Chuck, Dean, Carl, Vernon, Robert, Rob & Bob - Thanks very much for the feedback & compliments guys !


Very nice - Now the engine building bug is in your bloodstream, there is no known cure.
Bob, I've had the bug for many years - just never got round to it :)
Guess I'll have to change the name on my other build thread - that one will no no longer be my first engine ;D

Kind Regards, Arnold
 
Looks good. Having just finished mine, I know what a pain thse tiny parts are. They sure do sound nice, especially for their size.

We should start a rocking engines club!
 
rleete said:
Looks good. Having just finished mine, I know what a pain these tiny parts are. They sure do sound nice, especially for their size.

We should start a rocking engines club!

I got this 44mag club could use to takes shots at em once they be all lined up, OH wait, wrong kind of shot, my bad

Robert
 
I got this 44mag club could use to takes shots at em once they be all lined up, OH wait, wrong kind of shot, my bad
Rof} Rof}
Does that '44 have a scope on it ? - the way I shoot, you'll have to chain down the little buggers so they can't get away, give me a steady rest about 1/2 inch from it & I'll still miss! :hDe:

Took my ugly duckling to work today & left it standing on my desk - got some amazing responses from people walking in - from "Gee Wizz - I don't believe you made that at home" to "Oh it's quite!"... Problem is, it detracted from my work - kept thinking "What's next"!

Regards, Arnold
 
arnoldb said:
Rof} Rof}
Does that '44 have a scope on it ? - the way I shoot, you'll have to chain down the little buggers so they can't get away, give me a steady rest about 1/2 inch from it & I'll still miss! :hDe:

Took my ugly duckling to work today & left it standing on my desk - got some amazing responses from people walking in - from "Gee Wizz - I don't believe you made that at home" to "Oh it's quite!"... Problem is, it detracted from my work - kept thinking "What's next"!

Regards, Arnold

Don't you just love when even those who portray the sophisticated view, still stop and go "Oh Shinny Thing"

Common ground amongst us all :)

Robert
 
Hi Arnold

Seemed to have missed your thread never mind I've found it now.

Great job real nice informative write up,

Lovely little engine, when they kick into life you get a great lift.

The only problem now is sorting out what your next engine is goin to be.

Have fun

Stew

 
Thanks very much Stew.

I'm trying to choose between Elmer's Tiny and Fancy right now - I haven't built a wobbler type engine yet.
Might just go with the Fancy; slightly bigger - but then I first need some more stock; maybe build it a bit slower and bling it up.
If I go with the Tiny, I'll first have to make some smaller tooling, which is fine with me also ;)

Oh yes, and Thanks for introducing us to the little Rocker - I've missed it completely up till now!

Kind Regards, Arnold
 
To my Dad who gave me the Myford, and a LOT of life skills - THANKS DAD!!!


Great job. Congrats, I'm proud of you. Thanks for the accolade Shocked
Dad

Swarmaker:
Welcome now that you showed yourself we want an intro and we want to see YOUR projects.
Tin
 
Thanks for the welcome, Tin.
I am an " old toppie", ie retired, and my hobby is steel, wood, computers, electrics, electronics, photography, in fact anything technical that I can keep myself busy with. On the engineering side, I have a small workshop with modest lathe, milling machine, tool grinder, drill,and most tooling. I also have fully equipped wood and electronics workshops
When I retired I thought I could settle down and start to build a model gas turbine but I am kept very busy making impossible-to-get parts for, and doing repairs to boat engines, power tools etc.
So... my projects are not available now (chasing the girls, an ongoing project, cannot feature here!!)
I like the trend of this blog, and also the encouragement given to all. Keep it up
Regards to all
Ronald
 

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