Bruce-MacBeth Gas Engine Electric Plant

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Thats great looking and sounding, I even love the vintage looking lights your powering!

Great job!
 
Question:
If a two-cylinder version of this engine was to be built from the published drawings, what would be the best crank configuration? Just asking.


Frank
 
Who can argue with that? Thanks for the suggestions...I think.

The question still stands.


Frank

Haha that's funny.

But just so we all know, that post is not suggestions for you but rather ineffectual spam for construction contracting services in Haiphong Vietnam. A moderator should delete that post.
 
Hi Jeff,

Well done, runs very good with a lovely sound. What do you think about a period switchboard and some tiles on the floor?
Do you start it by hand or with the use of a power drill?
Anyway a very successful project. Heat off !

Kind regards,
Johan.
 
Hi Johan,
A switchboard and tile floor will be part of the my current project. It is progressing now. The Bruce-MacBeth usually starts easily with a few turns by hand. It runs on propane, which helps.

Jeff
 
Re: Posting # 22:
Hoping some forum members will speculate, or offer opinions regarding the crankshaft configuration for a modified, two-cylinder, version. One piston up, the other down... both up....??

Thanks,
Frank
 
Hi Frank,
Just some random thoughts. With a 180 degree crank you would stand a better chance of balancing due to mass up, mass down. Some Triumph motorcycle engines were 360 degree cranks, both up at the same time and operated fine. It's just that more counterweight is needed. Personally if I were to build one I think I would go with the 180 crank. You will also get a different firing cadence with the two configurations.
gbritnell
 
G. Britnell-

I appreciate the input, and for the explanations regarding both crankshaft options.


Frank
 
Beautiful engine. did u build the radiator or modify and existing product?
 
The radiator is a standard 120 mm radiator used by the overclocking computer gamers. There is quite a selection now of these radiators. Mine uses a 4 speed cooling fan powered by the the engine driven alternator.
Jeff
 
The Engine is outstanding. I would like to see a set of plans for the Alternator put into print I would like to build one but I don't have any idea where to start.

Mike
 
[FONT=&quot]Mfrick,[/FONT]
[FONT=&quot]While I am quite pleased with the B-M alternator it is not ideally suited to a model engine in the 500-700 RPM range for which it was designed. It is better suited to much slower RPM engines due to its rather high output voltage at 500-700 RPM. I suppose I could use a transformer to reduce the voltage, but the model then starts getting bulky and heavy.
[/FONT]
[FONT=&quot]On an IC engine project I am finishing up, I built another slow speed generator to address the weight and voltage issues I have with the B-M alternator. It was designed for a slow speed 2 cylinder 1” bore engine so the output was reduced to 3A @ 12vdc and 500 RPM. I am still chasing some finishing details on it, but I hope to share some photos and maybe a video soon.
[/FONT]
[FONT=&quot]If you have any specific questions, PM me.[/FONT]
[FONT=&quot]Jeff[/FONT]
 
Hello Jeff
I in the process of building the Macbeth out of the Home Shop Machinist mag and i have a question regarding the drilling of the intake and exhaust and coolant ports. I drill them as shown on the print and they seem to be backwards so I'm looking for some clarifications. On the print they show the bottom of the head and it just doesn't work or I not understanding the print.

Mike
wallbash.gif
 
Mike,
The print is correct. Note that on the upper left portion of page 38 the cylinder head assembly drawing item #19 shows four views. The center right hand view is labeled the bottom view of the head. The center left hand view is actually the top view of the head. Keep in mind you have to rotate the top view right to left to see the bottom view and things get reversed. The top most view shown is the exhaust manifold mating side of the head and the bottom most view is the intake manifold mating side of the head. I hope this clears it up for you.

Jeff
 
Hello Jeff

The problem that I have is the location of the center of the holes lands right at the bottom of the water jacket so when you drill the holes for either intake and or exhaust halve the hole ends up into the water jacket.

Mike:wall::wall:
 
So I'm building the Bruce MacBeth Engine What a great looking engine.
So I would like to have some basic dimensions for the distributor. I'm building it from scratch . So what I basically need is the overall diameter and the length of the cap and body rest is pc of cake. So any help would be greatly appreciated, rest of engine is coming along nicely. :thumbup:


Mike
 
Mike,
I used the distributor sold by Roy Sholl at S/S. The cap is 1" OD. The length of the current cap and base available from Roy is slightly longer so I cannot give you an OAL dimension. The real B-M engines did not use a distributor ignition system. They used two small magnetos, one on each end of the camshaft. Like air craft engines, they were redundant feeding two spark plugs per cylinder. Use boots on the spark plug cable ends with the smaller Viper spark plugs. If I were doing this engine over again I think I would eliminate the distributor and use two wasted spark type ignition systems. They would add a little more cost, but should be more dependable.
Jeff
 
Hi Jeff

Thanks for the reply and the information. I will look into your suggestion and look at building two magnetos to fit. My brother is an expert on magnetos he restores old engines so he's a good resource plus he will have something that I can use as a modeled to scale down. :thumbup:

Mike
 
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