A new Oz engine on the way?

[dazza 38]

I'm not an engineer but I have some understanding of economics and marketing. Aircraft engines are mostly priced based on what the market will bear due to the low volume. If it was profitable the market would be flooded with engines.

I totally agree and I am not a person in the industry that can answer why it is so. I'm thinking, either their costs are justified by low volume of sales or aviators are just taken for a ride. I am not trying to stir or anything, but I look at a modern motorcycle- eg- the new KTM LC8 V twin- 1190 cc 150 HP Adventure, V twin the whole bike sells for around 24K. It has electronics everywhere. Push button 100HP or 150 HP, fly by wire throttle etc etc. They are a low volume product, compared to say a popular Honda motor cycle. But I can see where the 24 K has gone, well sort off. But I cant see it in a Lyc o-360 if you know what I mean.

PS- I was going to use the Ducati Multistrada as a example, but being similar to the KTM it has a price of around $30K, so I didn't use it. :)

 

 

[facthunter]

Dazza, A hand built modern VINCENT engine costs 25 grand and there would be b...all profit in that. A replica Manx Norton or a Matchless G 50 is about 80K for the bike. Mass produced electronic parts don't cost much, and once the dies for the Al castings are made they can be quite cheap per unit. Aircraft engines never get to be produced like that. There are an enormous number of "variants" of a model as well.

 

Rolls Royce produced the Continental 0-2oo motors under licence for a while but couldn't make money out of them. Have a look at the UL range of flat motors. They have done a pretty good job of getting a few engines up and running. Nev

 

 

[facthunter]

You could do a fair bit of bench testing and stress it out or run it on a swamp boat. A properly engineered motor is capable of being designed from proven data and barring some severe oversight should run fine off the "plan". When you chase the "lightness" limit you get to a critical point where radii and finishes make the engine costly and probably a bit more likely to fail in service. You have to design it with a chosen service life too for running hours and also elapsed time and shelf life. Nev

 

 

[bexrbetter]

Apparently my cases have been machined and are in transit, maybe tomorrow or Tuesday arrive into my clutches.

 

 

[facthunter]

A "GOD" look would help if you could arrange it.

 

The water cooled heads have better metal than the originals. Nev

 

 

[damkia]

A "GOD" look would help if you could arrange it.The water cooled heads have better metal than the originals. Nev

Do you have "GOD"'s number to make sure he is there?

 

 

[facthunter]

I am only quoting the post as written. Nev

 

 

[Admin]

Please note that this thread has been broken into 2 threads as there has become 2 completely different engines being developed. This thread was started by the user Bexrbetter and who I might add graciously some time ago made a donation towards the site operating costs. The other thread titled "Developing a new engine" is by a new comer to the site and has come here to simply at this stage to promote his engine without asking for permission and is against the site rules of commercial promotion however, for the time being it has been left in the interest of discussion by site users...Site Admin

 

 

[bexrbetter]

A pair of machined crankshaft housings arrived for me yesterday, bit like Xmas - only I had to pay for the presents

 

Nice to sit the oil pump housing (front cover) and rear oil seal housing on and see a matched sump surface

 

Keen eyes will see the deck hieghts were determined by the oiling system, i.e. the front oil pump and main bearing feed gallery (starts where the shiny bungs are in place).

 

Small things like the OEM alternator bracket pictured that are available 'off the shelf ' help to make this project get to a result.

 

Later in the week I will throw some main shells in and try out the crank fitment and bore alignment although because it has been machined on OEM machines I would be surprised to see any issues.

 

 

 

 

 

 

 

[geoffreywh]

Looks great, minimum of excess material, i can't see "head gasket surface?" is there a bit missing that would form combustion chamber?

 

 

[bexrbetter]

Looks great, minimum of excess material, i can't see "head gasket surface?" is there a bit missing that would form combustion chamber?

Yes, all the usual casting lugs seen on an engine have been removed for min. weight, looks and cooling.

 

You are only seeing the outer crankshaft housings above and I am now designing the center casings that the head is affixed too and that's why you can't see a head gasket surface! Check the schematic below ...

 

 

 

[ozbear]

It's good to see you progressing so well Bex:smile:

 

 

[bexrbetter]

Just playing around today making sure there's no big issues.

 

I think you guys are going to like what I did today, walked into my local General Motors spare parts dealer and bought main and big end bearing shells, oil seals, etc. for "normal person" prices.

 

 

 

 

[geoffreywh]

That's a better pic with the crank fitted. Great, short stiff crank. Now , the "cylinder " part will acommodate the pistons so will be 2 x stroke + length long with a spigot sticking out at each end....? Have a slot? in the middle to form the combustion chamber, Thats going to be one hell of a "squish" effect! Ingenious. Has this been done before ? Uneven heating might be an issue? Going to look really odd.

 

 

[Camel]

Hi Bex, I think your concept is good, as a motor mechanic one of my tech projects was pull down and reassemble a commer knocker. How will you cool the motor and will you go for diesel ? How will the crank shafts link together ? What are the expected revs and will it need reduction ? I think the 100 and above horsepower is the go. Would the propeller drive allow for an adjustable prop ?

 

Good luck with your project and wish you all the best and I am sure it is going to be a success,

 

 

[bexrbetter]

How will you cool the motor and will you go for diesel ? How will the crank shafts link together ?

Water cooled.

 

Here's something I wrote about the cranks ..

 

 

 

In the development of the engine over the same time as light aviation, there has been a noticeable change. While the speed of a propeller hasn't changed, lets say 2500rpm is optimal for the moment, engine rpm most certainly has.

 

 

 

Where once an 80hp engine would turn at the same speed as the prop, modern engines are much more efficient turning at much higher speeds, lets use 5000rpm as optimal for the moment and of course are smaller and lighter while doing so.

 

 

 

This difference in speed has required the use of reduction gearing to change the engines optimal speed of 5000rpm to that of the propeller's speed of 2500rpm, i.e. a reduction of 2:1 is required (again example only). This of course can be found on the 80hp class leading engine as standard fitment.

 

 

 

With an OP engine, the 2 crankshafts must be geared together in order to operate in unison and I propose to use the idler gear used to mesh the crankshafts also as the reduction gearing for the propeller as described in this aproximate illustration showing the engine crankshafts turning at 5000rpm and converting that into 2500rpm at the propeller ...

 

 

 

 

 

 

Note that 2:1 is not a practical speed to operate at but this is simplistic explanation.

 

 

[Camel]

Very clever idea. Diesel ?

 

 

[bexrbetter]

Very clever idea. Diesel ?

Diesel fit most light aircraft but are fueled by petrol at least for the first model.

 

May look at diesel later but I know very little about diesels and would have to get specialists in to assist me.

 

 

[bexrbetter]

I'll recap for you as well camel and others, after 13 pages or so things can get lost ..

 

 

 

THE ENGINE: The engine concept is quite simple but for a variety of reasons has had no purpose until more modern era. The design is of a twin crankshaft, opposed piston (OP) engine of 3 cylinders which contain a pair of pistons each aiming at each other.

 

 

 

Why: Balance and compact are the main reasons. It's not hard to imagine even for the non-mechanically minded. When you catch a ball you feel the kinetic force strike your hand pushing your hand backwards, now imagine if 2 balls from opposite directions hit your hand at the same time, yes it would hurt, but your hand wouldn't move being pushed back and forward at the same time.

 

 

 

It's similar in an engine, when the piston reaches the top of the cylinder and the crankshaft tries to force it downwards, the piston doesn't want to change direction and tries to lift the crankshaft up with it and the opposite when it reaches the bottom off the cylinder, each time this happens you get a small jolt - this is a very simplistic explanation of what causes primary vibrations in engines and the reason your car has big rubber engine mounts to absorb them even after the manufacturer has designed and balanced the engine to the best of their ability.

 

 

 

In an opposed piston engine such as I am aiming for, the forces created by one side of the engine going one way are equalled by the other side of the engine going in the opposite direction so you have zero jolts, i.e. zero primary vibrations in theory in much reduced secondary vibrations.

 

 

 

Also with the simple layout of a OP, the design allows a standard 'off the shelf' automotive head to be used and as that is the single greatest expense of an engine, costs can be cut dramatically.

 

 

 

So an OP engine with a common automotive head afixed on top will take something like this basic form (sample only, not indicative of actual engine) ...

 

 

 

 

[Bandit12]

Hey Bex, I don't know if it had been asked yet (understand if you don't have/want to give details yet though) but do you have a ballpark RRP? Looking very nice so far.

 

 

[bexrbetter]

Hey Bex, I don't know if it had been asked yet (understand if you don't have/want to give details yet though) but do you have a ballpark RRP? Looking very nice so far.

No it's too early'a day yet but I would like to go to market at half price or better of the market class leader, i.e Rotax 912.

 

 

[Gnarly Gnu]

At work we would pay only up to 40% max for items made in China compared to western Europe / Japan, USA etc, just too many ongoing quality hassles. Yes I know when forced to they can and do produce quality items and very likely you can keep a good watch on quality if you are there to check each part in person but yeah, the country has sadly trashed its own reputation so you face an uphill marketing struggle.

 

 

[bexrbetter]

At work we would pay only up to 40% max for items made in China compared to western Europe / Japan, USA etc, just too many ongoing quality hassles. Yes I know when forced to they can and do produce quality items and very likely you can keep a good watch on quality if you are there to check each part in person but yeah, the country has sadly trashed its own reputation so you face an uphill marketing struggle.

It's amazing that many people's washing machine, fridge, kitchen appliances, TV, DVD, computer, furniture, etc, etc are all made in China and give good service, but when somebody goes to Supercheap and buys a $19.99 4" grinder on "Super Sale" and it breaks a day later it's thrown into the "typical of anything 'Made in China" basket

 

The real shame is that if you buy the proverbial $29.99 4" grinder like I do here, the service life is brilliant.

 

 

[Gnarly Gnu]

I'm quite familiar with the Party lines. The Chinese people all know this problem well themselves of course. I was referring more to multi $k machinery but yes the western owned or operated factories can produce good items for example. And of course goods from Taiwan (some would say it's the real China) are generally quite good now. It's just a shame the government for all its authoritarian control hasn't protected its own brand. Hopefully within a decade or so the situation will improve.

 

 

[bexrbetter]

The Chinese people all know this problem well themselves of course.

Yes they are accutely aware of the "Made in China" tag and don't understand why Western people keep ordering and buying rubbish!! They should start CAA (Cheap Ass Anomynous) i.e. "Hi, I'm John and I've been 4 weeks now without buying cheap crap and blaming China for my poor judgement"

 

It's now 2013 and the bulk of your post is more old style China and not very accurate portrait of today's China but relevant to this topic, it is today's China that I am able to produce a high quality engine product with absolute confidence.