Author Topic: Small capacity diesel engines  (Read 2411 times)

Offline Ramon

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Re: Small capacity diesel engines
« Reply #15 on: January 22, 2019, 04:48:15 PM »
Thanks Jo and Jason  :ThumbsUp: I wasn't aware they are now available to all - good all round eh.

Neil - the 'Weaver' is in the second of Jason's links. Many of these engines are side ports so don't know if they will be what you are after as they all tend to be somewhat 'Mills-ish'

Tug
"I ain't here for the long time but I am here for a good time"
(a very apt phrase - thanks to a well meaning MEM friend)

Online Jo

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Re: Small capacity diesel engines
« Reply #16 on: January 22, 2019, 06:18:45 PM »
Ron did a page on the Alpha: http://modelenginenews.org/design/design7.html

And his 0.1cc Compression Ignition engine Nano: http://modelenginenews.org/nano/index.html

Jo
Usus est optimum magister

Offline Neil-Lickfold

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Re: Small capacity diesel engines
« Reply #17 on: January 22, 2019, 08:57:00 PM »
Thanks for the links and all the replies.
Not sure what exactly I'll get around to making.
But when I do, will take pics etc and record it.
Neil

Offline Neil-Lickfold

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Re: Small capacity diesel engines
« Reply #18 on: January 25, 2019, 09:00:12 AM »
So my thoughts are to make 9.5mm bore engine with a 10.5mm stroke. It will be a steel liner, iron piston.  So far I am thinking of making it a simple with drilled holes schnurle type transfer system, with a side exhaust.  As I will throw the model with my right hand, it will have a Rh side exhuast. I am thinking of the carb being like  amills type, but with the induction under neath the exhaust port, so piston ported.
Initial timing numbers are the transfer around 120 deg and the Exhaust around 130 deg duration. Induction will be in the 110 to 120 total induction range, but thinking closer to the 110 at this stage. All the transfer passage volume will be in the liner wall, a bit like the OS12 engine does. The liner will have the cooling fins cut in like Cox engine. But will have a screw over Ali head for the comp screw. The outer Ali part will be 4032 . Not sure of the case material yet. May make it as an experiment in loss wax casting and get it cast in LM13. Been thinking of making the liner from A2 tool steel. Rod will be 2024, wristpin will be a needle roller and  a press fit to the piston.  Crank I am looking at either 4340 or H13, and nitrided for the crank pin hardness, but masking the threaded area. It will be a bronze bushed case. 
I wont be starting any making on this project untill, sept / October or so.
If there is any real stand out issue with materials I have chosen, it will be appreciated to have suggestions for better materials.
Neil

Offline Ramon

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Re: Small capacity diesel engines
« Reply #19 on: January 25, 2019, 10:12:41 AM »
Sounds good Neil  :ThumbsUp: - don't think you'll be wearing that out in a hurry  :D

Tug
"I ain't here for the long time but I am here for a good time"
(a very apt phrase - thanks to a well meaning MEM friend)

Offline ChuckKey

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Re: Small capacity diesel engines
« Reply #20 on: January 26, 2019, 12:46:05 AM »
In reply to the OP, a look at Model Engine News confirmed the Davies-Charlton DC 'Dart' at 0.5cc (I had one as a kid) and an interesting piece on the DC 'Bambi', probably the smallest production diesel, at 0.15cc. That is 7/32" bore x 1/4" stroke!

Offline Ramon

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Re: Small capacity diesel engines
« Reply #21 on: January 26, 2019, 09:17:29 PM »
Hi 'Chuck',

The DC Bambi was indeed a tiny engine and as you rightly say was possibly the smallest production diesel engine made. Production methods on piston and liners must have been very tight and I believe they could be difficult to start or even run. Quite expensive relative to other engines of the period they never the less had their place but mainly I would say more as a novelty than a really practical power plant.

Last year I re-bored and renovated an old ED Comp Special for a friend. Much to my delight he presented me with one as a thank you.


I have not run it, it sits on display in my small aeromodelling 'nostalgia cabinet' but I know he did  and even built a very small control line model for it - on thread lines it flew but only just ;)

Sitting in the hand it doesn't seem that small but here it is beside a 2.5cc Oliver Tiger ...


.. and to put in perspective for me, beside the 5cc version of the SuperTigre G31 1cc engine. That said I think it now makes the Tigre look more like a 10cc or even larger ::)


Hope this helps add a little inspiration Neil

As you know the Oliver Tiger is on the cards for the next 5cc version - I'm intending to start next week end all being well.

Regards - Tug
"I ain't here for the long time but I am here for a good time"
(a very apt phrase - thanks to a well meaning MEM friend)