Mate diesel from Motor Boys plan book (long)

[ariz]

hello guys
here we are again with a new engine
I don't like the premises, but few words are necessary here
I would like to document my bilds and publish them in the 'work in progress' section, but I discovered that I cannot do it for now: I have little time to work in the shop and mostly I'm too tired to take pictures, upload and explain them
for us who are not british/english speaking, it isn't so easy to write long post full of detailed explanations, expecially in the night, when one is tired after a working day
I browse the forum often and it is always a pleasure, but rarely I find the energy to post and interact with you, and this is a great worry for me, expecially when I see admirable masterpieces but I cannot find the words to express
fortunately there is the 'photos and video' section where I can put a brief summary of the build
hummm... I apologize for the premise, I don't like them! I had already said it?

well, I'm sorry for the quality of the pics too: I took them under a LED lamp and they are a bit too dark
in return, the flaws were very emphasized, maybe for the tangent light, indeed the engine isn't so bad

this is my 4th engine, and my second IC engine
I won the POM in august 2009 with my second steam engine, so in the last year I built two IC engine, the scuderi and this one
the scuderi still doesn't run ( :-\ ), hope that this one would be luckiest

it is the australian mate diesel by david owen, and I took the plans on the 'model engine plan book' published by the motor boys (http://modelenginenews.org/), that I bought some time ago
well, now the pics...

the crankcase, aluminium

the crankshaft, steel

the head and backplate, aluminium

the conrod and prop driver (aluminium) and the compression screw, steel

cylinder (steel), piston and contrapiston, cast iron: the inside and outside of the cylinder looks worse than they are

this pic of the head is to show what happens when the soft wheel that you're using to polish a part catch it and shoot it away (little signs at 9 - 10 o'clock)

the spraybar, brass (here not soldered yet)

this is the setup to lap the piston, suggested in the book: very effective

the remaining pics are a sequence of the assembly

well, what else?
now I need to build a binding, something to secure the engine to the bench
some sort of tank for the gasoline (btw, what type may I use to start the engine?)
and a propeller... but I don't think to fly a plane with the engine, may I use something else instead of the propeller to start the engine?
or I need to buy a propeller, because I'm not able to build it :-\

that's all... I apologize if there are too many pics in the post, hope that you like them
thank you

 

[kustomkb]

Very nice work Ariz, your engine looks great!

Interesting set-up with the die handle for external lapping.

I look forward to see the engine running..

 

[SAM in LA]

Ariz,

Thank you for showing us your pictures.

Your engine looks great.

Show us a movie when it is running.

SAM

 

[m_kilde]

Ariz

Thank you for the story. A post like this can never have too many pictures ;D

 

[GailInNM]

Ariz,
Nice photo photo review of your engine build. Thank you.

For fuel you will need to blend your own if no commercial model diesel fuel is available. A discussion of the fuel requirements can be seen at:

http://modelenginenews.org/faq/index.html#qa1

I used to blend my own, but now use a commercial fuel as it is easily available.
Bob (Maryak) has built two diesels in the work in process section and mixed his own fuel as no commercial fuel was available in Australia.

You can run the Mate with a flywheel but only for brief periods of time as it will probably overheat without airflow over the cooling fins.

Gail in NM

 

[thayer]

If you can build that engine the prop shouldn't be any trouble at all. Here is a page with the basics. Just substitute hardwood for the balsa shown and cut from a solid piece.

http://www.gryffinaero.com/models/ffpages/tips/propcarve.html

Thayer

 

[gbritnell]

Ariz, very nice work indeed. I think the parts came out great. The crankshaft machining looks super. I hope you have better luck running it than your previous effort. As nice as it looks I should think you won't have any problems.
George

 

[zeeprogrammer]

No apologies please.
That's some fine work. Thanks for posting the pics.

 

[ariz]

thank you all for your kindly words, I appreciated them very much

thank you gail for the info about the fuel mix and the flywheel
I forgot to mention the Maryak's thread on the build of an aero engine, I drew it with both hands ;D

thanks thayer fot the link on the prop, but I think you overstimate my skills

 

[ariz]

...and two!!!

2 engines that don't run at all are a very depressing experience. I start to think that I'm simply not able to make IC engines. steam engines, or rather steam engines running on air, are within my reach, but anything more complex is out of my reach.
this is very sad, but it is a fact

anyway, I waited a couple of months for the ether and when finally I got it I mixed my own fuel: 1 part of ether, 1 of diesel fuel and 1 of castor oil.
I tried everything and more, but apart from some occasional pop (1-2 seconds, maybe 30-50 revs) , the engine didn't run.

I know that you guys would like to help me but, believe me, save your breath... there is nothing to do. the timing is correct and the only possible cause could be a leakage or a poor compression. there aren't leakages (immersed the engine in a liquide), so the last candidate is the combination cylinder - piston (and contrapiston).
but I built another couple of pistons, more tight, and lapped the cylinder every time with the new piston... I don't have any more resource, and I'm downhearted too...
so, today I abandoned the project and placed the engine in a drawer, out of sight.
I don't want to see it anymore.

now I am uncertain whether to resume the scuderi engine to see if I can fix it (with the great risk of a new disheartening experience) or to start a completely new building
in this case I would like to build the most easy IC engine of the universe, so if I will fail again, I'll understand that this hobby isn't for me
time ago I dreamed to build a V2 or a V8... what a stupid arrogant!

 

[Maryak]

Ariz,

The diesel fuel for these engines is not diesel fuel but kerosene. Aviation fuel or power kerosene is better if you can get it but home kerosene is OK. A starting off mix is 35% Kerosene, 35% Ether and 30% Castor oil. Later you can reduce the Castor oil to 25% and increase the Kerosene to 40%. You can also add 1.5% IPN, (nitro) and a 1.5% less Kerosene. This is normally done after a run in period.

Hope this helps and good luck.


Best Regards

 

[Kermit]

Warm that cylinder up, however you can. Oven, torch, boiling water. Then give it another try.

 

[krv3000]

brill engine ;D

 

[ariz]

thank you
Bob I had heard that kerosene and diesel fuel are nearly the same...
Kermit I'll try what you have suggested (in a couple of days, because my right arm is sore for several attempts to start the engine ;D)

thanks again

 

[Maryak]

Bob I had heard that kerosene and diesel fuel are nearly the same...

Ariz,

I don't believe the above is correct - below are extracts from their specs to highlight the important differences.

Spec Kerosene Automotive Distillate.
Viscosity @ 40 1.25 3.4
Flash Point C 43 80
GCV MJ/l 37.1 39.3

Also I forgot to mention that the order of mixing the fuel is relevant to a good mix. The ether and castor oil are mixed together before adding this solution to the kerosene. Then shake well. Don't mix more than 100ml at a time and keep in a sealed container or the ether will evaporate out of the mix.

Hope this helps a bit more.

Best Regards
Bob

View attachment PREPARATIONS FOR RUNNING.doc

 

[ariz]

hummm... the differences in the specs are very interesting...
so it is the order of mixing the fuel... hummmm

here I can find kerosene only in drum of 25 liter, but the desire to see the engine running is too much for stopping now

ok, I'll give it another try
thank you Bob

 

[cidrontmg]

Ariz,
Another thing you might use for kerosene is known as Lamp Oil, sold for oil lamps. One common brand is Lamplight Farms, american, but readily available here in Portugal in DIY shops and camping suppliers. There are other brands also here.

Lamp Oil is "refined" kerosene. It doesn´t soot the lamp glass as easily as ordinary kero. And it´s also less smelly (practically no smell at all). So it will be better in a diesel motor. It´s available in 1 liter plastic flasks (instead of 25 liters!), and costs next to nothing. It´s still sold, although Portugal is 100% electrified, not a single village relies on oil lamps. It will certainly be better than ordinary diesel motor fuel
Ordinary kero is smelly, but in a small diesel, the smell comes mainly from burning castor oil anyway... And a nice smell it is ;D

 

[ariz]

thank you too Cid, sure 1 liter is better than 25!!!

I'll report the news, if there will be any

 

[quinette7]

Ariz-

I only randomly visit this site, but when I saw your post today, I just had to submit my first reply here.

Don't give up on your "Mate" Diesel! It will run! Mine did! - but not at first. It turned into a true learning experience.

I built mine about 20 years ago from the aluminum extrusion kit. It was one of my projects, and my first attempt at an IC engine, so my skills weren't adequate. I too was disappointed when it didn't run, but I didn't know how to make it any better, and had no one to turn to for help. The compression was too low, and the connecting rod probably would have broken if it had run.

I must say that judging from your pictures, yours is much better built than mine is.

When it didn't run, I set it aside - for 20 years. Then I built a Stirling engine from an Andy Ross kit - and it didn't run. Too little compression and too much friction. Then it took me 14 years to complete a Young "Hit-n-Miss" engine. It RAN! Then I took a second at the Stirling, and with guidance from Andy Ross, I got it to run, too. After frustrations, but final success, with two more Stirlings, I figured it was time to apply what I had learned to the "Mate".

I got the "Mate" running just last month. I posted a 10 second video of it on YouTube.

[ame]http://www.youtube.com/watch?v=4ZvmdtID2qY[/ame]

Maybe my experience will help you.

I found that I had too much leakage past both the piston and the contra-piston, so I made both of them over. The original plans suggested using Brasso metal polish for the lapping compound. That didn’t work for me. After trying several other things, I found that diamond paste worked real well when embedded into an aluminum lap. I’ve read that copper works even better, but I used the material that I had on hand. I re-lapped the original cylinder bore with an ID lap, and the pistons with an OD lap. I believe the cylinder had a slight taper, so as I lapped the power piston would fit incrementally further up the cylinder. I stopped when the piston was tight at the point it touched Top Dead Center. The contra-piston fits very tightly into the cylinder – that was a main leakage point previously. It won’t retract when I turn the engine by hand, but it does when the engine fires. When I rotated the crankshaft with the power piston in the cylinder, but not the contra-piston, it turned freely except for a small but noticeable amount of friction at TDC. Fully assembled, there is a definite little “pop” when I spin the propeller.

I used a commercial model airplane diesel fuel sold by Davis Diesel Development http://www.davisdieseldevelopment.com/home.php because a local hobby shop had some on the shelf. I have not yet tried to mix my own fuel. I suggest that if you mix your own fuel to try to test IT first in a commercial model airplane diesel engine. I believe that ether is a key component, and if it evaporates too quickly, even commercial engines won’t run.

In the video, you will notice that my engine has a spinner on the propeller. That is because it will not start by hand – even to restart when the engine is warm. I have to break RULE #1 of running model airplane diesel engines, which is. “Never use an electric starter.” I have to use an electric starter with my “Mate”. The danger with an electric starter is that if there is too much liquid fuel in the cylinder, you can damage the connecting rod or crank pin when the piston hits TDC. So I don’t put priming fuel on the piston, and no more than a drop into the venturi. Mine will start without priming fluid, now that I have the settings dialed in. I suggest you flip the prop over by hand a time or two before using the electric starter, just to make sure.

My engine runs best when the contra-piston is backed off ¾ turn from the point that the two pistons touch, and the needle valve is 2 turns open. I used inch standard threads for these parts, and I expect that you used metric according to the original drawings, so your settings may be a little different than mine, but not too much. My engine responds well to adjusting the compression and mixture, but both have a wide range in which the engine will run.

Oh, yeah, wear earplugs when you start it. It will be pleasingly LOUD! Shivers went thru my body when mine finally ran.

Bob G

 

[ariz]

thank you Bob G
I'm honored that you made your first post in answer to my problems, and reading your experience with the Mate encouraged me to continue in the attempts to run it.
I'm just doing exactly what you did: today I started to make another piston, because I suspect that most of the problems are there... lack of compression
In some days we'll know if there will be another Mate running out there or not

thank you again, a karma point for you (and everyone who replied )