3cc Diesel - My first ICE

[Maryak]

NickG,

Thanks for your support and interest

Yes the piston goes to within 1/4" of the top without binding. ;D

The lapping on its' own took me 4 hours, including fiddling about with the lap and correcting my mistake with the pear shape. Approximately the same amount of time was spent lapping the cylinder and I anticipate at least 2 hours for the contra piston. Say 10 hours all up of just lapping.

Are you in the unfortunate position of having a job, a large family, an even larger dog which requires walking. Or are you even more unfortunate with time on your hands and trying to live off the pension ??? ???

Regards
Bob

 

[NickG]

Bob,

This is a very interesting post for me and I'm sure many others!. Having build a few oscillating engines or wobblers, I remember trying to build a 0.8cc Sparey Diesel when I first started this hobby (I was about 15). Needless to say I didn't get very far!!!

That sounds good, I know from doing various steam engines and recently my hot air engine that it reeps rewards to pay great attention to getting the fit between the cylinder and piston right.

Well, I can't say I'm unfortunate, I'm very lucky really, I have a 2 1/2 year old son and a 3 month old son. However, that and a nagging wife isn't conducive to spending quality time in the garage! I can imagine living off the pension will be difficult these days but some time would be nice. Having said that, I don't know where I wasted the 5 years prior to having kids!

Nick

 

[Maryak]

Nick,

Thanks for your reply. I remember those times of a young family. Don't be too hard on Mrs Nick, 2 under 3 makes for a very busy and tired Mum :bow: where a good result is all the nappies off the line and dry ready for re-use. :

From what I have read in the lead up to this project, 3cc is about as small as you should be for a 1st attempt at a model IC engine. Have a look at WarEagles Crusader, as an alternative. He is more than happy to share his knowledge with us all.

Regards
Bob

 

[Maryak]

Sorveltaja,

Each to their own, I admire how you are persevering with your engine :bow: and I know how it can be frustrating at times.

On my steam mill engine, I made 2 cylinders, 4 crankshafts and 3 eccentric straps before I got them right :

It's all part of the fun

So far Ive only had to make 2 crankcases with this engine, but there is still some way to go :-\ :-\

Best Regards
Bob

 

[SERCEFLYER]

Maybe a dumb question: what exactly is Dremel paste? Brasso is a polishing compound, right?

About the contra-piston: make sure it is a tight fit in the top of cylinder. One way is to create a thin-walled (.030 thick) contra-piston with a 1/2 degree outside taper. This causes the walls to compress a bit and create a tight and springy fit.

Just a thought.

George

 

[Maryak]

George,

No question is a dumb question, if we don't ask questions we will have trouble finding the answers :bow:

Dremel is a small electric tool which revs through a good range up to 15000 rpm. In the polishing and grinding kit is a small container of polishing paste, a bit like a cutting compound in a heavy duty car polish, (never thought of that until now :).

Brasso is a metal polish mainly for brass, hence the name brasso. Museum curators and those who want a long life from their brass artifacts would kill you if you used brasso, as I found out to my distress when polishing an old binnacle. :-[

I assume you are referring to the David Owen method of making contra pistons ??? Thought I'd give the old way a try 1st and if NBG either in assembly or later, will give it a go.

Best Regards
Bob

 

[Maryak]

Once more into the fray rode the intrepid lapper ;D

Today saw the finish of the contra piston and a start made on the conrod. I agonised over the choice of material for quite some time The original called for steel on steel, which was for me a no-no Then I considered steel with bronze bushes, but short of making both big end and gudgeon smaller, (which I did not want), couldn't see a satisfactory solution. Next I considered bronze, but rejected it, for no explainable reason other than I thought it might fracture ??? ??? ???. Last was aluminium which has been recommended in various other publications as being suitable. In the end I opted for Aluminium :-\

Sizing the contra piston lap.

Sizing the mandrel for the contra piston.

Test fit of CP on mandrel.

Loctite the CP on the mandrel.

Almost there

The contra piston a nice tight fit in the cylinder.

A little heat to remove the CP from it's mandrel.

Both pistons in the cylinder.

Hacking out a lump of aluminium for the conrod

That's all for today.

 

[SERCEFLYER]

Yes, I was referring to the David Owen method. I love that you are using traditional laps and techniques.

I will be super impressed if your 1st piston/liner results in a runner. I went through at least 3-4 pistons and liners before I got a first pop!!!

Jumping ahead a bit: do you plan on mixing your own fuel?

George

 

[Maryak]

George,

Thanks for your input and continued support. I too will be super impressed if it runs 1st up

Fuel is a tricky one, due to all the restrictions on chemicals various. I suspect Ethyl Ether could be a problem ???

But will X that bridge when I come to it. I understand it is possible to buy premixed brews from the model aircraft/racing car fraternity, but hey lets get the engine built ;D

Best Regards
Bob

 

[Maryak]

Sorry guys waiting for Mrs M's movie to finish downloading - its only been going 7 hours but not enough bandwidth to handle piccys

Regards
Bob

 

[Maryak]

Well, Mrs M's movie finished so I can post today's effort, ;D (that's 2 movies she's downloaded, the first and the last ;D, by mutual agreement of course :).

Slacked off again today and only managed half a day on the model the other half being tanks as my partner in crime is up north in Mintabi at his opal mine, ( a delicate operation involving a D9 bulldozer and gelignite. . I'm about as close as I want to be, (800km South). "Perfectly safe" he says as we are busy stuffing ourselves under the ute to avoid the fall out from one of his efforts

I digress, back to the engine.

Made a little progress with the conrod and its' machining/supporting jig.

Carving off a lump of Alu for the jig.

Squaring said jig lump.

The jig and conrod blanks.

marking out the conrod blank.

The conrod blank ready for dirlling and reaming.

The set up for drilling and reaming.

Reaming the gudgeon pin end with a homemade reamer from 3/16" round HSS.

The jig and conrod blanks drilled and reamed.

Brass rod for the jig locating pins.

Press fitting the big end pin into the jig.

The big end pin positioned with the conrod blank being offered up.

And so ended another week - will see, you, yous, y'awl - next week - have a good one guys.

 

[wareagle]

Progress!! Everyting is looking great! The excitement is building here, and I'm looking forward to seeing you fire it up! Heck, it's a shame we couldn't be there with ya for the inaugral huff and chuff.

For your "large" downloads, here's a thought... My method of downloading large files (which isn't very often) is to set it up to download as I go to bed. This way, the computer does all of the work and there isn't a problem with the computer or connection being slowed down. If Mrs. Maryak wants movies, let 'er have 'em. Just download them during sleepy time!

Keep up the great work!!

 

[Maryak]

W/E,

Thanks as usual for your helpful advise. I wish you could all be here too for the inaugural fire up

Mrs M missed her internet access, as much as I did. She uses it to keep in contact with her family in Siberia and Moscow using a program called "Free Call" plus Skype, ICQ and Windows live. She was as peeved as I was.

The time allocation for Oz, from the Russian movie server, is from 10:30 to 16:30 our time. This plus we have a 5GB download allowance before we are shaped has certainly put a stopper in the works.

Lastly we have 2 satellite dishes which receive between them 5 Russian channels and on average I make about 2-3 Russian DVD's a week of films, serials and documentaries so she's not missing much ;D

Not exactly Model Engineering, but you deserve an explanation after all you help and support for my project :bow:

Ah the things we do for those we love : : :

Best Regards
Bob

 

[malcolmt]

"Ah the things we do for those we love"

And our wives :big: :big: :big: :big:

It's alright mines asleep so i can get away with saying that (This time)

Kind Regards

Malcolm

 

[Maryak]

Malcolm,

What can I say ??? : ??? : ??? :

Regards
Bob

 

[Maryak]

Hi Guys,

Had a bit of a nasty shock today. Mrs M had a giddy turn so off to the doc followed by the hospital.

Thought it was a stroke but thankfully no.

All's well that ends well but after all that I'd had more than enough for one day.

Hopefully tomorrow can proceed at a more normal pace.

Regards
Bob

 

[jack404]

Hope everythings ok mate

Give your better half my best wishes and i'll be hoping that everythings ok

the S word is a awful scary subject.

take care or your Mrs and Yourself eh

jack

 

[Maryak]

Thanks Jack ;D

 

[wareagle]

Bob, I am glad to hear that Mrs. M's medical issue wasn't as serious as first thought. Take good care of her and know that she is in our thoughts. Best wishes for a rapid and full recovery!

 

[CrewCab]

All the best to you both Bob, take care.

CC