Dusting off my old scratchbuilt engines making them run again.

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I'm dusting off my old scratch built air powered engines and putting them back into running condition again.
These engines were designed and built about a decade ago.

I'l call this engine #1 for this video series.

This is probably the 3rd engine I built after I got the hang of machining parts to make running engines.

Here is a video of it running.



and some pics:
SUNP0001.JPG SUNP0002.JPG SUNP0003.JPG
 
Good plan. Most of the engine we build are run a couple of time to prove ourselves it runs an put away. I have the same plan, after finishing the current build I am going to run them all.
 
Cute engine. It seems like it has dual poppet valves on each cylinder? are they driven from 4 cams on the crankshaft, via pushrods? It w0uld be nice to see a closeup of the rockers, and a pic of the crankshaft. It looks like you could adjust the angle between the cylinders (?) Why did you settle on that angle?
 
Cute engine. It seems like it has dual poppet valves on each cylinder? are they driven from 4 cams on the crankshaft, via pushrods? It w0uld be nice to see a closeup of the rockers, and a pic of the crankshaft. It looks like you could adjust the angle between the cylinders (?) Why did you settle on that angle?

Thank you,
Yes, I'm using 4 eccentrics to supply the cam action
I think the angle is around 45* included, I chose it mainly for asthetics, it gives a nice Vee look to it.

The crankshaft is built up.
Here is the crankshaft, and the eccentrics:

SUNP0001.JPG


1.5.JPG


and the rocker arm assembly:

SUNP0006.JPG


SUNP0007.JPG


SUNP0008.JPG


SUNP0009.JPG


Here is a short video of the parts moving under manual control slowly spinning the flywheel by hand.



............................................................
 
Good plan. Most of the engine we build are run a couple of time to prove ourselves it runs an put away. I have the same plan, after finishing the current build I am going to run them all.

Thank you,
yeh it needed a lot of dusting off, but after a good cleaning and some machine oil the old engine runs like new again.
 
Very nice. Where did you get the plans for this one?
 
Very nice. Where did you get the plans for this one?

Hi, thank you!
I didn't have any plans for it, it's scratch built, I was designing it as I was building it.
 
Very nice. Where did you get the plans for this one?
Thank you.

When you mentioned plans, I didn't have any plans from another source, but I did draw up my own plans, as I was building it. After you mentioned about plans for this, I looked through my cad files to see if I could find them for this engine, and I found them.

If you want I could load them into this thread, However a word of caution (I cannot guarantee any accuracy on the dimensions or even the drawings, as my method involves deviating away from my plans as needed, and most of the time I don't bother updating the plans to reflect the changes, some of the drawings are just conceptual dimensions, all thrown together to get me in some direction for machining the parts.)

However if your interested in looking over them to see what is feesable and whats not, your most welcome to have them, let me know and I'll upload them into this thread.
 
That would be fantastic. I love the sound. If you have any notes on the build I could email you as well.
 
Hi, I would like to keep everything on the forum here,
however before I upload any of the plans for this, here are some more pics.

These are areas on the engine that I have no dimensions or any design notes on
placement of these parts, they were all done through trial and error.

Here is an example of problem solving, that needs to be done.

the push rod tubes need to be as parrallel as posible on the eccentrics on the crankshaft,
but need to exit through the top cover of the engine at an angle so as to end up in the
right place to meet with the rocker arms, it requires taking measurements to know
what compound angle you need, than making a jig to hold the push rod bracket
at a compound angle to drill through.

here the tubes (push rods) are sitting very close to parallel to each other as possible.
SUNP0001.JPG


exiting the top cover they end up at an angle to each other.
SUNP0002.JPG


full view
SUNP0003.JPG


front view
SUNP0004.JPG


coming back the other side
SUNP0005.JPG


SUNP0006.JPG


the angles arrangement of one of the cylinders
SUNP0007.JPG


SUNP0008.JPG


As you can see there is a lot of things that you need to figure out on your own, that
I just don't have any dimensions or design steps to show, it all has to be built by
your own instincts of problem solving in mechanical design.


I'll still upload the plans, I drew up, in the next few days, but again the drawings are more conceptual thoughts
than actual build dimensions, on most of the areas.

If anything, the whole upload would be a good way to get the idea of the build of this engine, but I wouldn't
machine any parts according to the plans, until each part dimension is thoroughly looked over.


Please understand
I'm not trying to discourage you, but I am alerting to you, these plans are not plans I would put out for the forum to build off of, because they were done through trial and error, and this engine is built on ones own ability to do problem solving.


I'll upload the plans next time.
 
Please do not trust these plans, they were done on the fly, check and recheck all dimensions
before committing to machining any parts on these plans.

These plans are not uploaded to be used in a build for the forum, if you do you
are under your own discretion to use them for a project build.



cylinder page1.jpg


cylinder page2.jpg


cylinder page3.JPG


valve bracket.JPG



intake manifold.JPG



cylinder head.JPG




intake valve.JPG



exhaust valve.JPG



spring retainers.JPG





piston.JPG
 
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con rod.JPG



rocker arm brkts..JPG



crankshaft page1.JPG





crankshaft page2.JPG




crankshaft support page1.JPG




crankshaft support page2.JPG




end panels.JPG



top panels.JPG





cylinder clamps page 1.JPG
 
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cylinder clamps page 2.JPG



eccentrics.JPG


lift rod guides.JPG




rocker arm.JPG



flywheel.JPG




throttle.JPG






cylinde-valve-piston assembly.JPG




The rest are a bunch of drawings scattered, that I collected, these are just
conceptual ideas, and work arounds trying to figure out angles and placement of components and such.


design concepts page   1.JPG
 
design concepts page   2.JPG



design concepts page  3.JPG



design concepts page  4.JPG



6.JPG



7.JPG



8.JPG



9.JPG



10.JPG




11.JPG



12.JPG



If I find any more I'll upload them.
 
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Thank you.

When you mentioned plans, I didn't have any plans from another source, but I did draw up my own plans, as I was building it. After you mentioned about plans for this, I looked through my cad files to see if I could find them for this engine, and I found them.

If you want I could load them into this thread, However a word of caution (I cannot guarantee any accuracy on the dimensions or even the drawings, as my method involves deviating away from my plans as needed, and most of the time I don't bother updating the plans to reflect the changes, some of the drawings are just conceptual dimensions, all thrown together to get me in some direction for machining the parts.)

However if your interested in looking over them to see what is feesable and whats not, your most welcome to have them, let me know and I'll upload them into this thread.

The way you do it is the same way I did with my engine !
 
The way you do it is the same way I did with my engine !

I don't think I could design engines to the degree I made them, without my CAD programs.
Yet there are people on this forum, who still use drafting boards to do there designs,
To me that is amazing, my hats off, to those who can design mechanical engines without
CAD programs, it must take years of experience and know how to pull that off.
 

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