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Got round to fitting the valve gear to test fit and function. The exhaust rocker shaft is fixed. There is an eccentric on the inlet rocker. It is 1mm off centre so the valve lift can be adjusted as on the original engine. Hopefully it will have the same effect as on the original. I decided on a simple venturi carb as the engine power and speed should be controlled on the inlet valve.

I have to say that having drilled 3mm clevis pins with a 1mm drill for the split pins(cotterpins). My admiration for the guys who make those miniature multicylinder engines has gone through the roof.
It was only possible for me to do it by making a drill jig.

IMG_0027.jpg
 
A lot of rain in this part of the world so got a bit of time to do some detail work. To give an idea of scale the brass tube on the oiler is 2mm O/D

Brake band and operating lever
WP_20170721_15_35_10_Pro.jpg

Drip feed oiler with pipework for the three main bearings
WP_20170721_16_00_05_Pro.jpg

Barrel and head assembly with carb, exhaust and cylinder drip feed oiler
WP_20170721_15_59_38_Pro.jpg
 
Now we're getting there. A bit of tidying up scratched paint required but everything works as it should.
Engine 1.pngEngine 2.png

Engine 3.png
The hall sensor wires can be seen on the right. The magnet is in the brass wheel under the brake band. I would have liked it under the engine out of sight but could not see an easy way to adjust its position there.
The drip feed lubricator is not fitted yet. I need to set the drip rate before fitting as there is no other way to do it. As this is intended to be slow running and a total loss system I will just set to drip every five seconds or so.

Working on the tank now. A lot of polishing required here.Tank.png
I hope to test run next week.:hDe:
 
Hi Tony,

I have been following your build. You are doing a great job on the Hicks engine. I have been currently building a 1/8 scale Monterey Clipper for the last year and a half. Upon completion of the boat I will build a 1/8 model of a Hicks engine. It will be a later version of the Hicks with the push rods on the side of engine instead of in the rear. The engine will not power the boat it will have a small electric motor in it to turn the flywheel and push rods.

If you are interested in my build of the Monterey Clipper I can post the link.

Ed

DSC07605.jpg
 
Thanks Ed. Great looking boat. Please leave a link I would love to see the build.

Not much success with the trials today.
Despite building three ignition modules (had to buy quantities of components so enough to build five) and testing them before installation I failed to get a spark. Tested the the circuit again and found the one that I picked to install had a broken joint on the output transistor. A quick drop of solder, tested and all was OK.
Still no spark when fitted to the engine. I had checked that the brass brake band did not shield the magnet when stationary and it was OK. However a bit of googling and I realised I had totally forgotten Lenz's law.(It's been a long while since I learned anything about electrics and magnetism) The band was shielding the magnet when it was moving. I relocated the magnet onto the face of the wheel, moved the hall sensor accordingly and immediately got a good spark.
I tried numerous settings of the carb , from zero to three turns. All I could get was a few pops then a wet plug. I am happy with valve and ignition timing so I guess the problem is the carb. I tried to make the carb look sort of similar to the original with a long intake so maybe thats the problem. Also it seems the mixture adjustment is too coarse. I guess I may try a proprietory carb next.
 
Jerry Howell designed the Bill 4 stroke engine and that had a long induction tube. He said that it was very difficult to get the model to run on liquid fuels, but it ran OK on propane. Your carb looks to have a long induction tube as well, so maybe it would be worth trying it out on propane.

Dave
The Emerald Isle
 
Hi Ed.
Started reading about the build. Great job and some good information there. PatMat has a couple of plans on his site which look promising but if you are aware of anything in cad that could be scaled up I would be eternally grateful.
Tony
 
Hi Dave.
I had thought about gas but ruled it out for now as I would have to buy the gas and a regulator before even starting anything . I noticed that my tank lends itself to the Jan Ridders type system so I am going to try that. I just need to decide on the size of intake pipe. The engine is 25mm bore x 32 stroke so around 15.5 CC and I am hoping I can get it to run from 400 RPM to maximum of 800/1000 RPM. I would be very grateful for any advice on how to judge the size of intake.
 
Hi Tony,

Sorry I don't know of any plans in CAD.

Ed
 
Tony
I'm away at the moment, but from memory, Bill's vertical intake is 1/4" dia. and about 1-1/2" long with the mixer at the bottom.
Bill-1.jpg Cyl head & valve train.jpg

A couple of pics (from Jerry Howell) showing his induction pipe and mixer.

Dave
The Emerald Isle
 
Thanks Dave.
That all looks pretty similar to mine which is 6mm X 32 long.
Strangely enough(or not) I just noticed the carb on the first engine pic I posted, has been moved nearer the head. The original is shown in the second engine pic. I have been following threads on a couple of other sites with absolutely stunning non working scale engine builds and they also show the long intake as per the original. However I googled a few more engine pics and it seems a lot of engines had the carb moved nearer the head, probably for good reason. So that looks like an option and in keeping with the real thing.
So first job is to put on the surface intake. Hopefully this weekend. If that works then I will look into placing a better carb nearer the head. The carb on the Bill looks interesting too. I will try to find some detail on that.
 
So I made up a check valve and an air adjuster and connected up to a 'spice jar' with 4mm bore tube. The connectors further reduced that to 3mm. It started straight away but I needed to set the air intake fully closed to get it to run so there is no throttle adjustment to change the speed.
Moving the inlet valve eccentric does work but the rev range is restricted by the maximum speed I was getting.
At least I know it will run and I am heading in the right direction and it looks like the original 6mm inlet is sized correctly. I only ran it for a few seconds indoors as there was no water connected and no extraction. After filling the ground floor up with exhaust fumes and the smell of burnt oil (her words), I have been restricted to testing outdoors or fitting an extraction fan.
I have posted a video on you tube [ame]https://www.youtube.com/watch?v=ytjZuBZ4Tsc&feature=youtu.be[/ame] I apologise in advance for the quality. I have to invest a bit of time in practicing with a camera and editing out the rubbish,
I am pretty confident that I can get it working as I hoped. I am feeling pretty chuffed as its my first attempt at a model engine.
 
Congratulations on getting it running. It looks and sounds great.

Ed
 
Thanks Ed. I am going to play around with the carburation a bit more on this one until I get it to run the way I want.
Now that I am confident that I can do this I want to make another with a lot more scale detail in it. I might also look at the later side valve model to see if thats any easier to build especially the camshaft. The one I used on this came from an ASP engine with a gear mod. It works fine but there is limited adjustment. Also I want to use the camshaft for ignition so there is no lost spark.
 
Hello Tony excellent idling.
Are you happy with thermosyphon cooling?
I had this kind of cooling on one of my engines but I was absolutely
disappointed with efficiency.
What is for that big lever in front of engine ....CLUTCH?
Could you please send more detailed picture of this mechanism ?
thank you
 
Thank you Brian. The surface carb is not flexible enough for boat use and does not give the control I want. It did prove that everything else was OK though. Hopefully with some work on the carburation I can get it to the running state I would like, I will then check the power output in the launch hull before I start on a more detailed version for a scale monterey clipper.

Hi Kadora. For my purposes thermosyphon cooling is enough for short runs. The water path I designed, means the cold water flows in the bottom flywheel side of the barrel, around and up to the rear of the head then across the head before exiting on flywheel side again. It seems to work well enough.
The lever is non working. I just used the wheel to mount the magnet for the hall sensor. It just seemed a nice idea to model the clutch lever into it so it looks more like the real one. I intend to use a reversing box in the boat so it will remain non working on the new version just better detail. I also intend to put the hall sensor on a false magneto driven from the camshaft on the next one.
This was a bit of a test for me also to see what I was capable of. I have not really done any machining for more than 30years.
 
Wonderfully done ! Thirty years of not machining anything hasn't affected your abilities. Must be like a fine wine, only gets better with a little age! I can only hope the same applies to me but I'm already getting to my "advanced" years. Beautiful engine!
 

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