Mery Explosive Engine

[Chipmaster]

The next stage was to mount the cylinder onto the base using six studs through the flange of the base, the drawings specified 5-40 UNC thread.
As I don’t have UNC fasteners I used 5BA which is the same diameter. Drilling and threading the six holes in the cylinder flange would be easy especially using the bolt circle function of the DRO recently fitted to my milling machine. However, the base casting is about 13 inches long and my milling machine doesn’t have enough clearance to hold it in a vertical position.
My approach was to machine a guide with six 2.65mm holes on the 2.125” diameter circle specified. The resulting guide could be positioned over each flange with a snug fitting piece of aluminium inside the flanges.

Cylinder attached temporarily by Andy, on Flickr

IMG_0412 by Andy, on Flickr

IMG_0413 by Andy, on Flickr

I tried to hold the base casting on my pillar drill but that didn't work so I had to use a cordless drill.

  IMG_0418 by Andy, on Flickr

After the guide was used to locate the tapping size holes I opened them up to 1/8" to guide the tap.

IMG_0419 by Andy, on Flickr]]

Cylinder held by two 5BA studs.

IMG_0423 by Andy, on Flickr

There was enough time left before dinner  to mill the inlet and exhaust ports to the correct height, same plane and vertical.

 Milling the inlet ports flat by Andy, on Flickr

Milling the exhaust ports flat by Andy, on Flickr

Exhaust ports flat, in line and vertical. by Andy, on Flickr

Exhaust ports flat, in line and vertical. by Andy, on Flickr

Andy

[Jo]

Doing well Andy, and I love the new DRO 

Jo

[stevendavis]

Nice work!

[Chipmaster]

Cheers Jo 
Unfortunately DROs don’t prevent silly mistakes. I’ve only just realised I have the cylinder on incorrectly in that the inlets and exhausts are on the wrong sides and it’s been like that for weeks.

Oh well I think I can cope with that, it means my engine could be unique being opposite handed to the drawings The bolt circle for the six studs in the plain cylinder head on the opposite end is supposed to be two inches as opposed to the 2.125 I’ve put in the wrong end. Not a catastrophe as I could turn the cylinder round and use the slightly larger bolt circle for the cylinder head. I haven’t drilled the other end of the cylinder yet and I reckon the DRO will be capable of reproducing the required 2.125” bolt circle.
My first thoughts are to leave the flanges I have just done alone and carry on building. I don’t see any problems with that, I’ll be content if it runs.
Andy

[Chipmaster]

Cylinder revisited now the Inlet and exhaust ports are on the correct sides.

 IMG_0440 by Andy, on Flickr

IMG_0441 by Andy, on Flickr

Inlet ports by Andy, on Flickr

Exhaust by Andy, on Flickr

End of cylinder drilled and tapped ready for the cylinder head,

IMG_0443 by Andy, on Flickr

Andy

[pirmin]

 

great progress ! i wonder how many people purchased the castings without knowing in what they got into. definetly a tricky kit "

[Chipmaster]

That’s a fair observation Pirmin, I have experienced a few moments in this build when I felt buyers remorse, particularly two days ago when I realised I’d attached the cylinder back to front. Being a self taught amateur I wouldn’t have attempted this kit without reading Internet articles about building this model and previewing the drawings. “You’ve got to know your limitations”
Andy

[Roger B]

That model is certainly reaching the size limits of your machines  Keep up the good work  we all want to hear it running   

[pirmin]

talking about limitations

i can sing a song about that" I wanted to build the Otto gas engine so Bad , knowing it will be on the limit for my machines. in fact i just went to a CNC shop today to make me a new fixture from wich i can reference from ,knowing it is machined square.

Also , i am so glad i have Dave otto on my side with my Build!

i am not sure how i would deal without a strong model engineering community

However,i think u can get away with your port missmatch, a youtuber i watch, built a steam engine and she made a very similiar mistake leaving her probably with the only Mill enigne with everything mirrored on the other side ....sh*t happens, but its important to make something good from it !

[Chipmaster]

Cheers Roger and Pirmin - your Deutz D2 is progressing well.
I think the remaining parts of this Mery model are within my machine tools capacity but I must take more care interpreting the drawings in future. There are a couple of details on the cylinder drawings I don’t understand so I sent an enquiry to Martin Models but they haven’t responded.
Are there any fellow MEM members who have built the model who could advise please ?
I have refrained from including images of the drawings in this build log, perhaps appropriate excerpts from the drawings would be acceptable?
Andy

[Dave Otto]

I would think a photo of only the area in the drawing in question would be ok. We may be able to help after seeing that.
I can also check with my friend to see what he says once we understand the question.

Also, thank you Pirmin for the kind words.

Dave

[Jasonb]

Post your questions, some members have the castings and drawings and may be able to help.

[Jo]

I have refrained from including images of the drawings in this build log, perhaps appropriate excerpts from the drawings would be acceptable?

Copyright Law is very clear: you are allowed to share a small amount of a copywritten item for the purpose of discussion.  So an appropriate excerpt of a drawing shared as part of a discussion is legal.

I can't see Martin Model having a leg to stand on if between us we can solve a "feature"  on their drawings and make it available to other modelers so they can make their model Mery.

Jo

[Jasonb]

Or even make their Mery Go Round

[Chipmaster]

OK, what are these four holes for? They are halfway along the cylinder on each side.

What are these holes for by Andy, on Flickr

I don't see them on these beautifully finished models....

<a href="https://www.youtube.com/watch?v=Wxx-qQ5uiBE" target="_blank">http://www.youtube.com/watch?v=Wxx-qQ5uiBE</a>

<a href="https://www.youtube.com/watch?v=EFZ_DyDaMgw" target="_blank">http://www.youtube.com/watch?v=EFZ_DyDaMgw</a>

<a href="https://www.youtube.com/watch?v=Uhr54g2UKps" target="_blank">http://www.youtube.com/watch?v=Uhr54g2UKps</a>

Or on the full size engine.

<a href="https://www.youtube.com/watch?v=CF-IR3gRyc0" target="_blank">http://www.youtube.com/watch?v=CF-IR3gRyc0</a>

Andy