Maudslay Marine Engine

[crueby]

It looks good to me Chuck. The extra mass will help it run slower perhaps which seem right for such an engine. Nice work on the flywheel!!

Bill

If the flywheel is going to be painted, the right colors can help too.

f

Since the flywheel isn't brass, I have thought about painting it, at least the spokes and hub.  But I hadn't given any thought as to colors...

Another handy feature of 3d CAD sw, you can assign colors and play with combinations.

[kvom]

Prismatic has a brass powder coat that could work.  I'd be happy to do it once I'm happy with my own results.

https://www.prismaticpowders.com/shop/powder-coating-colors/PPS-4431/top-brass

[cfellows]

Had to take a few days off but was back in the shop today.  The 1/8" brass sheet for the frame sides came in today, but I'm not going to CNC cut those until I get a bit farther along.  I did, however, do a test cut using 1/8" thick hardboard (masonite for the old timers).  I painted it yellow so it would show up better.



And a preview of what it will look like assembled...



Those brass rods need to be cut off so the brass insert extends all the way to the base, inside the feet.

I also got the valve made today. 



Hopefully this will give folks a better idea of how it works.  The valve will rotate 45 degrees.  The vertical slot in the middle will alternately supply air to the top and the bottom of the cylinder.  The drilled holes on the radius connect through to the axial exhaust hole which extends out the back.  As Ive said before, I'm not a big fan of rotary valves.  They are really hard to seal and are not very efficient.  Hopefully it'll work without too much hissing and puffing of escaping air. 

A couple more pictures of the valve with the cylinder...







Chuck

[zeeprogrammer]

That's looking good Chuck.

I've been following along. I think the flywheel came out great. 

[crueby]

Very interesting valve setup, amazing how many combinations there are.


That circle work on the frame is going to really set it off.


 

[Jasonb]

Coming along well

Would it be worth leaving a few "tabs" on the edge of the side panels and milling matching slots into the round legs to help keep things together while soldering?

[Ramon Wilson]

Nice work Chuck  and good to see the part I've been waiting for 

I confess I've been trying to work out the sequence on the valve with not a great deal of success - however it all becomes instantly clear 

One thing I notice as it stands in the image is that it appears that the exhaust is going to be open to atmosphere at the valve end making it difficult to plumb away from the engine as it will be moving through the arc of the cylinder movement.

I am wondering if a further circumferential groove could be put in the valve toward the end with a connecting hole though to the central exhaust. The far hole in the valve block would need to be blanked off (which could help a tad with the sealing problems you mention too)

This could then pick up a hole in the exhaust side of the valve block going through to the cylinder pivot hole. The cylinder pivot hole would have to be blanked off in the middle of course to separate the central hole into two but this would allow inlet and exhaust to be on the centre line?

Not sure if this thinking is sound but it's mentioned with best intention so hope you won't mind I hadn't intended to make any further engines but yours has caught my imagination - I have found a couple of pieces of brass that if soldered together will get me a flywheel rim 

Looking forwards to more of your progress

Regards - Tug

[cfellows]

Thanks, guys, for the support and positive comments.

Jason, although I've noodled around with ways to register the center piece with the rods while soldering, I hadn't thought of tabs, a worthy consideration.  I've also given some thought to how I might eliminate soldering altogether.  I'm not particularly against soldering, I'm just not very experienced with it and little skeptical of my ability to do a presentable job of it.

Tug, I haven't really given much thought to the exhaust other than providing a common exit point from the engine.   It would not be difficult to modify the valve so the exhaust was routed back into the back side of the cylinder pivot pin.  The design of the valve and porting is such that I could pretty easily make a new valve that would accomplish that.  But, the more surface features I mill into that the valve, the more it's like to leak air and work inefficiently.  In fact, I suspect I'll have to remake the rotary valve using lapping and other techniques to optimize the fit and minimize the leaks.

In the meantime, I'll be focusing on completing the frame pieces.

[Jasonb]

I suppose that if you want to keep away from soldering that it should be possible to drill and tap the ends of the round legs, drill and counterbore the feet and top piece for some socket cap screws and if the decorative plates had tabs they would almost hold themselves in place once the feet were stopped from spreading as they are fixed to the base.

[cfellows]

This morning I've been focused on getting accurate drawings of the engine components into Fusion 360.  I discovered a new feature (to me) where I can insert a DXF file directly into a component as a sketch without having to do an upload/import as separate operations.  Greatly speeds up and simplifies the process of using the DXF files I created.  Here's a drawing of what I have in Fusion 360 so far...



The process has been.

1.  Draw the part in Microsoft Visio.
2.  Save the part, from Visio, into a DXF file.
3.  Load the DXF file into CamBam.
     a.  I can use CamBam to join all the line segments which Visio often leaves separated.
     b.  I can also then use CamBam to export a cleaner DXF file with which Fusion 360 will import as a solid, 2D profile
     c.  I also use CamBam to generate the G-Code which Mach3 will use to CNC machine the part.
4.  Load the DXF file into Fusion 360 and expand the 2D drawing into a 3D part, assembling the individual components into an assembly.

I suppose it sounds complicated, but it's really pretty smooth at this point.

[Tennessee Whiskey]

Now that design looks wonderful Chuck. The insert could also be fastened with dowels and a shot of Locktite, either from the inside or out. If the fit was spot on and once it’s all polished, probably wouldn’t be seen. 

Cletus

[cfellows]

Now that design looks wonderful Chuck. The insert could also be fastened with dowels and a shot of Locktite, either from the inside or out. If the fit was spot on and once it’s all polished, probably wouldn’t be seen. 

Cletus2.5

Thanks, Cletus.  I added a couple of rounded disks at the top of each rod today.  I also drilled the parts and pinned everything together with 2.5mm steel rod, snug fit.

[zeeprogrammer]

Looks great Chuck. I thing it's a very interesting engine. 

[cfellows]

Looks great Chuck. I thing it's a very interesting engine. 

Thanks, Zee.  Nice to have you along for ride. 

[cfellows]

One final picture for the day.  I've been back in Fusion 360 most of the evening.  Here's a the result of my latest efforts there...



I've decided to put the cylinder between the uprights rather than opposite the flywheel, like the picture of the single cylinder version.