Manson Engine

[Plani]

Hello Everyone

After reading here for quite a while it's time for me to make some contribution. Therefore I will try and show how I'm making my little Manson Engine.

This is what it should look like, once it's finished:



And the cutaway view:


I think the Manson Engine ist the one where you get a running heatengine with the least amount of moving parts 
Therefore this engine wont get any fancy features. Every part is only as complicated as absolutly nececary.


Plani

[Plani]

Since it's the biggest and most fun part to make, I started with the Cooler/Engine body. 
Unfortunately, I didn't think of taking pictures while turning the part  , sorry about that....

So the journey begins with the cooler on the mill.
A round pocket is milled into the side of the cooler:


A hole is drilled ant tapped M5 to attach the post:


It took some thinking  until I realised that it would be the easyest for the further operations when the cooler would already sit on its post. So the post was quickly made and boltet onto the cooler really tight. So I could clamp the assembly in a collet block an adjust it straight:


From there on it was easy to index the part:


And then to drill and where needed to tap the rest of the holes from different sides:




Finished part:



Plani

[yogi]

Hey Plani!

Good to have you on board! 
I have been intrigued by Manson engines for quite some time, and will be following along closely.
Great start, and I'm looking forward to see more as the engine comes together.

Yogi

[b.lindsey]

Nice start Plani! I will be following along too. Is this your design?

Bill

[crueby]

Excellent start!

Does this design use a graphite cylinder or piston, or just normal materials?

 

[Plani]

Thank you guys 

Bill, this is actually the second attempt at this engine. I've already made one which is also running. But in the meantime I saw some Manson engines in the internet which run much faster than mine. So I decided to make some changes to the design (bigger bore, shorter stroke and a different porting) and try it again. Hopefully that will improve performance 

Chris, one design goal of this engine was also to make it as simple as possible. Therefore there are no plans for exotic materials. The cylinder will be made from steel and the piston from brass.


Plani

[Plani]

Next Part to be made was the cylinder. It's turned from steel bar stock:


The bore is prepared, there is still some material left on the inside as well as on the outside:


The cylinder is then clamped in a collet block to make the slot for the porting:


Back on the lathe, the outside diameter was finished. The excess material from the first step is now removed. This was left there in case something would be distorted by the slitting of the cylinder:


The Cylinder was then cut off the stock and the bore was brought to its final size. There is no chamfering on this end of the bore because this would affect the timing of the opening of the port:



Plani

[b.lindsey]

Nice finish on that cylinder!!

Bill

[yogi]

Nice work!     

How wide is the slot you milled in the cylinder?

Yogi

[Plani]

Thank you, Bill 

Yogi, the slot was planned to be 1mm wide. But since i had only a 0.8mm slitting saw at hand I made it 0.8mm. The with of this slot is not really critical because it is only one edge that makes the timing.

Plani

[Ian S C]

I'll be following this one closely, I'v only built versions of the Stirling type hot air motors.
Ian S C

[Plani]

Hi Ian, glad to have you along too!

Next Part to make was the piston:


I had the intention to make it pretty much the same way as the cylinder. Slitting the Port, this time the slot is made 1mm wide, since on this one both edges contribute to the pressure relive at the end of the stroke:


The hole for the con rod pin was drilled and reamed:


Bit since the brass stock I had was just long enough to make the piston, there was no stock left for clamping. So I made a mandrel on which the piston was to be fastened by an allan bolt:


Turning the piston to its final size:


Finished part:



Next up, the part that holds the displacer:


Turned around and bored to a sliding fit where it will be fixed to the piston:


Finished. The small hole going through the center is to prevent any pressure building up in the displacer and so keeping the glass from popping off:


Piston preassembled using loctite:



Plani

[b.lindsey]

Still following along Plani. I wasn't all that familiar with these engines so am learning a lot along the way.

Bill

[Plani]

Thanks Bill, and stay tuned, there are not a lot more parts till we shall know if it's a runner 

The conrod was milled from some aluminum stock:


The holes drilled and reamed and then the part was cut off the stock surfaced on the backside:


Like so:


For the main bearing the stand was made pretty much the same way. Some stock was surfaced to thickness and then the contour was milled as well as the bore for the Bearing:




The part was then cut off the stock, turned upside down, surfaced and mounting holes drilled:


The Bearing itself is made from brass:


The bearing preassembled using loctite:



Now there is only the crankdisc, flywheel and the shaft missing...

Plani

[yogi]

Great work Plani! 
Looking forward to the next parts and assembly... 

[b.lindsey]

Nice finish on those plani....well done!

Bill

[Plani]

Yogi and Bill, thanks a lot for the kind comments 

I the mean time I was getting really itchy wanting to know if this thing is going to work at all. And therefore the whole picture taking for the rest of the parts somehow misfired  ... But it was straight forward turnig jobs anyways for the Flywheel and the crank. The cut off test tubes I had already, this was by the way the thing that sparked this whole build.
So assembly was pretty easy for this handful of Parts.

Aaaaaaand voila:

The little alcohol burner and the mounting board are borrowed from the old engine. This one has been thoroughly "tested" (a.k.a played with  ) by the apprentices at work. That's why there are some scars and burn marks...


Engine in action  :
<a href="https://www.youtube.com/watch?v=RHV5Z21tOyQ" target="_blank">http://www.youtube.com/watch?v=RHV5Z21tOyQ</a>

The engine started right on the first try and is running pretty consistent. Although I was hoping for a couple more rpm, I'm pretty happy with the outcome.

Plani

[Ye-Ole Steam Dude]

Sure looks good in the video and a really cool sound.

[b.lindsey]

Very nice Plani!!   So the inner test tube is held on by the internal O-rings and the outer test tube is held in by the two O-rings in the finned part? Just want to make sure I am seeing things the right way.

Bill

[awJCKDup]

Very nice, yes very nice indeed. Fine workmanship. Did increasing the bore and the shorter stroke, give you increased RPM'S over the first one?
Thanks for the build.

John

[Ian S C]

Very nice running motor, and it will probably run a bit faster as it gets run in. it might be worth experimenting with flywheels, i'd strat with one about the same weight, but slightly larger diameter, with the weight consentrated at the rim, and spokes or holesbetween the rim and the hub, weight in this part is not helping the motor too much, just adding weight on the bearings.
The above is just my idea of model engines, i build then fiddle around to see if I can extract a milli watt more power.
Ian S C

[Plani]

Thank you guys for the kind comments  its very much appreciated.

Bill, That's exactly the way it's done an this engine. There are two reasons for me to do it that way: Aluminum is expanding a lot more when heated than glass. Therefore it's better to have something flexible in between. And also the test tubes have some tolerances in roundness. The O-Rings can take care of these as well.

John, I made a really precise guesstimation (just looking at it  ) and by this the rpm have doubled. So yes, it worked out pretty well.

Ian, thank you for the input. I will look into that.

Plani

[yogi]

Nice runner Plani! Well done!