Bruce Macbeth Engine, European Version

[fumopuc]

Last week end I was able to do the first assemble with the two flywheels and checking the first hand driven movement of the crank drive.
I have been very happy with the result so far.
<a href="https://www.youtube.com/watch?v=iHl5ofu3a50" target="_blank">http://www.youtube.com/watch?v=iHl5ofu3a50</a>

[fumopuc]

My next adventure was started immediately, the keyway grooves, never done before so far.
When I have made my CAD design by the original drawings with all metric adaptions in 2017, I have chosen a 3 mm key for it.
Knowing than already, that a 3 mm guide for the 3 mm broach is for a 10 mm shaft available only.
My camshaft is 12 mm, so I thought there will a way, I only have to find it.
First idea was to make an open bush, 12x1 mm and adjust it between the purchased guide an the hole in my flywheel.
Good plan, but the purchased guide for the broach is in length 22 mm only and my hub in the flywheel does have 26 mm in length.
So the broach would be 4 mm without any support, no good idea.
A sketch was made to make the right guide for my special application.
The job itself was done than easily and the broach is still alive in one piece.

[fumopuc]

One other additional job to do.
The Bruce Macbeth engine does have in my opinion one very special characteristic attribute, the square wholes in the flywheel to get them adjusted to the right starting positing of the crankshaft.
I took the opportunity to order the Hemingway Rotary Broaching Kit, but it will take some to get it and to make the tool than. So for another project, may be.
It was time now to find the dusty rotary table in lowest drawer again, banned there due to all the CNC jobs which have canceled the need of any further usage.
A 4 mm hole was made, followed by a square milling operation with a 2 mm cutter.
24 wholes, 12 in each flywheel and of course if have mixed it up one time.
But JB WELD is the friend of all of us. Finally it will be painted or powder coated and than nobody will see it anymore.
I hope the very last story with this casting will be to remove the burr. I have planed to do this job at the garden table already in the coming warmer spring time.
Two days during last week, we have seen 17° C already but last night we have get another 3 cm of snow again.
This white cover was not really seen during the whole past winter time, but currently it is melting fast already.   

[gbritnell]

Hi Achim,
I don't know the background of this engine but a similar engine, the Holt tractor engine, had notches in the flywheel also. Given the large displacement of these engines I'm assuming it was quite impractical to crank start them so pockets were put into the flywheel so that the engine could be started with a large bar. Now the notches weren't just a hole that the bar would fit into but rather they were tapered on one side so that when the engine started the bar would be easier to retract. I have heard many stories about occasions when the bar didn't come out and one can only guess the consequences!
Still following your excellent build.
gbritnell

[Vixen]

Hello Achim, George.

Many large (huge) marine diesel engines also have those pockets in the flywheel. The ship sized engines, I refer to, were far to big to start by hand. The pockets were there to rotate the engine during maintenance or when a bearing had to be tightened or remetaled or replaced. The process of turning the engine was known as 'baring the engine'. Because that's what they used, a big bar and wedges to inch the crankshaft into the desired position.

Mike

[fumopuc]

Now the notches weren't just a hole that the bar would fit into but rather they were tapered on one side so that when the engine started the bar would be easier to retract.
gbritnell

Hi George, thanks for watching and the friendly words.
Some time ago I have heard from this tapered styled holes also already. I am sure, that there has the one and other not so amused action happened if it was not used in the correct way.
I hope that all of you will apologize, that I have tried to give it the right appearance and I have not done the one to one scale down, also with the taper inside.

Wishing all the best for you and your families, because the feeling her in south of Germany is already a bit strange.
Nearly all shops and restaurants are closed, you are not allowed to leave your house, only for work, doctor and the supermarket so far.
Since today the Police started to control peoples behavior. 

[Rustkolector]

Hello Achim,
Your B-M engine project is coming along nicely. The B-M engines were all built with compressed air starting so the flywheel holes were for barring the flywheels to the starting position.

Stay Home. Stay well.

Best Regards,
Jeff

[MJM460]

Hi Achim, I for one am sure that no apologies are necessary, you are doing a wonderful job of that engine.  I learn heaps from how you have fabricated complex parts, and got them looking so good.

It is indeed strange times, it will be a different world when we emerge and have to try and get things going again.  In the mean time, lots of time for our hobbies.

MJM460

[fumopuc]

Hi Jeff,
Hi MJM460,
thanks for the encouraging comments.

[steamer]

Yes    Baring holes.    Some of the larger engines had baring engines to turn the engines over.....Worm gear for a 750 HP compound from a steam tug boat.  You can just see the swinging bracket at the left end of the engine bed.   a worm would be fitted there with a shaft that has a large wrench hex.  The bracket also had a curve slot so that it could be swung into engagement with a large worm wheel that clamped to the coupling flange ( 2 halves).   Once you swung the gear into place it would also prevent the engine from rotating...which makes working on a engine like this safe....the crankshaft alone weighs 9000 pounds.   A simple flange with baring holes can be seen to the right of the Seabury 100 HP triple from a steam yacht.

Dave

[fumopuc]

Also a pleasure to watch


[youtube1]https://youtu.be/GQTVUFGBfxs

[/youtube1]

[crueby]

Yes    Baring holes.    Some of the larger engines had baring engines to turn the engines over.....Worm gear for a 750 HP compound from a steam tug boat.  You can just see the swinging bracket at the left end of the engine bed.   a worm would be fitted there with a shaft that has a large wrench hex.  The bracket also had a curve slot so that it could be swung into engagement with a large worm wheel that clamped to the coupling flange ( 2 halves).   Once you swung the gear into place it would also prevent the engine from rotating...which makes working on a engine like this safe....the crankshaft alone weighs 9000 pounds.   A simple flange with baring holes can be seen to the right of the Seabury 100 HP triple from a steam yacht.

Dave

That looks like it was taken just outside the sshipyard buyilding at Mytsic Seaport, right?   

[steamer]

Yes    Baring holes.    Some of the larger engines had baring engines to turn the engines over.....Worm gear for a 750 HP compound from a steam tug boat.  You can just see the swinging bracket at the left end of the engine bed.   a worm would be fitted there with a shaft that has a large wrench hex.  The bracket also had a curve slot so that it could be swung into engagement with a large worm wheel that clamped to the coupling flange ( 2 halves).   Once you swung the gear into place it would also prevent the engine from rotating...which makes working on a engine like this safe....the crankshaft alone weighs 9000 pounds.   A simple flange with baring holes can be seen to the right of the Seabury 100 HP triple from a steam yacht.

Dave

That looks like it was taken just outside the sshipyard buyilding at Mytsic Seaport, right?   

correct....The mustachiod dude is me!
 

[fumopuc]

Hi everybody, some impressions of the continued liner job.
All my cylinders are a bit conical inside in one or the other direction. Something about 0,02 mm.
So I have matched the outer liner machining with each liner to this specific situation.
The interference should be nearly 0 with a very small tendency of a slightly bigger liner by less than 0,01 mm, theoretical.
Three times it was nearly perfect to get the liners pushed in easily with the arbor press.
The very last one has had a little surprise for me and was stuck at the very last 5 mm.
Seeing a thick wall aluminum tube in the shelf, has solved my panic and it could not resist anymore.

[Don1966]

Looking great Achim still with you!.......


 
Don