Vega V twin Aero engine

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After finally completing my Kerzel H&M engine I am now probably getting too ambitious and intend to build a Vega 9cc V Twin.
I have located the articles and at present translating them into SolidWorks to check and refine the build.
Has anyone here any experience of building this engine?

Vega 1.jpg
 
Do you have any pictures or video of your Kerzel? I am currently building one.
 
Do you have any pictures or video of your Kerzel? I am currently building one.

Hi Weez,
I will be posting them soon on the finished projects forum. I did post some GrabCad and a link to an earlier video which will be updated soon.
https://grabcad.com/library/hit-and-miss-engine-kerzel-design--1

Good luck with your build and if you need any help then drop me a line. I had a lot of problems over the build duration but have managed to sort them all.

Rich
 
Don't know too much about this V-twin. Is it a sparker or, glow-plug engine?

Will you be posting details/drawings of your version of the head design, rockers, valves, cages, etc?

Good luck with the build.


Frank
 
Hi Frank,
The original design is for glow plug and that makes it simpler all round. I always re-draw the plans in SolidWorks as it allows me to identify errors which there often are in plans. I will translate these into 2d drawings eventually and will probably do it metric as opposed to the original which is imperial (1986 plans)
 
creast:

Thanks for the quick answers. Can't wait for the building of the engine to proceed, and, for the 2D drawings, whenever.

Have fun.


Frank
 
Hi Peter,
Thanks for the link.. very useful. I will have to see if the author is still here and can answer any queries I may have. Cheers!
 
Well, I have finally started the long haul of making the Vega V twin.
Most of the machining is done where I work and so is done piecemeal at either my lunch break or maybe an hour after worktime. Some machining is done at home on my Myford ML7 but I do prefer the rather worn out Colchester at work for its capacity to remove stock.
The crankcase is almost complete and just requires the holes for the cylinders to be bored out.
The crankshaft is about 90% there and is made from 17-4PH which is pretty strong compared to the EN8 suggested.
Turning the crankpin wasn't as straightforward, since for the required offset, my 4 jaw chuck bore was too small to allow the shaft to be within the chuck.
The solution was to create a fixture from aluminium bar to hold the crankshaft and then swing that in the four jaw. The whole lathe was wobbling a bit with unbalance but it all went ok. The crank web now requires milling.
So far I spent approx 7 hours to create the two parts to this stage.

Fixture.jpg


Crankcase.jpg


Crankshaft.jpg
 
Very nice machining progress Creast. Just curious, when you did your SW CAD conversion from original 2D paper plans, did the parts & dimensions & assembly come together nicely without errors? Did you make any significant changes along the way outside of metric-ation?

What's your plan of attack on the piston rings in particular? Did they call for a gap + heat treat jig, or commercial RC-type ring, or..?
 
Hi peter,
No it hasn't come together nicely to be honest. There is a lot of information missing from the magazine articles and that becomes apparent when you try to draw it up in CAD.
Of course there is always the dilemma of trying to round up figures in metric to make it look nicer but that isn't always possible.
also the original drawings are in awful fractions! LOL!
I am still adjusting things as I make it. The original used BA threads and I am trying to avoid that but can see the BA sizes sometimes look better.
Its probably best I make to my drawings and spot the errors in my drawings as I go along before I publish my version.
The rings are pretty normal CI jobs with a heat treat to set. This engine actually use two rings in one groove. No gaps are specified as far as I can see having read it a few times so will play it by ear so to speak.
I contacted a member here who was building one but never completed it so I wonder if it will ever run anyway??? Oh God! :eek:

Regards
Rich





Very nice machining progress Creast. Just curious, when you did your SW CAD conversion from original 2D paper plans, did the parts & dimensions & assembly come together nicely without errors? Did you make any significant changes along the way outside of metric-ation?

What's your plan of attack on the piston rings in particular? Did they call for a gap + heat treat jig, or commercial RC-type ring, or..?
 
Hi peter, No it hasn't come together nicely to be honest. There is a lot of information missing from the magazine articles and that becomes apparent when you try to draw it up in CAD. Rich

Thanks for your candor Rich. You will persevere and it will run!

Reason for my question was I think I had those same paper plans many moons ago (without the article, ugh!). I tried replicating the design into 2D cad. Well.. probably a combination of my newbyness, the drawings & dimensions, not visualizing 3D parts assembly properly... I shelved the project before even beginning. Probably why I have more plans & articles than metal shavings & engines... But One Day! ;D
Look forward to your progress. Your design iteration will be golden!
 
Hello Rich

You could do something usefull for mankind if You stop trying to make it according to incomplete plans.
If You make it as two stroke with a central exhaust valve actuated by a cam on crankshaft part number counts is less
A british mr Wilksch tried to make something like that for small aircrafts and failed as far as I know,mostly due to fixation on making diesel and being three cylinder inline inverted.
A two cylinder two stroke inverted V2 petrol and turboed can do very well up to 300 horsepower were gasturbines take over anyway.

komplet.jpg
 
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Thanks peter,
I can relate to what you are saying and to be honest its much easier in 3D CAD than 2D as you literally build it like its real and can check all the movements and for parts interfering.
I use SolidWorks in my profession as a design engineer but my machining skills are lacking, but getting a wee bit better as I go. Having got two Stirling engines and my hit and miss engine running I am fairly confident but I do know getting things to run can take a while,, ie weeks or months. LOL!
 
Hi Niels,
Not really quite sure I understand what you are saying.
Two stroke V twins have to have isolated crankcase partitions to work or a boosted crankcase pressure by some other means, just the same for radials.
This is a four stroke albeit glow plug and that is what I chose to try. The plans may not be perfect but hey it gives me 90% and the rest will be sorted one way or another.
On the subject of inverted engines, I always found these more susceptible to hydraulic lock up if flooding occurs so I would rather go for vertical V.
 
Two stroke V-twin seems to be a popular engine for people to want to try. I'm guessing it's the love of V-twins and that two strokes seem simpler than four. For me, the valve train on a four stroke is the intimidating part.


Sent from my iPad using Model Engines
 
Two stroke V-twin seems to be a popular engine for people to want to try. I'm guessing it's the love of V-twins and that two strokes seem simpler than four. For me, the valve train on a four stroke is the intimidating part.


Sent from my iPad using Model Engines

Yes, 2 strokes are easier but in a V twin? I have not found any plans that cover this in any real way.. maybe you can point me to one?
And yes.. I agree.. valve trains are very intimidating :)
 
V twin two strokes will only work if you can have separet crankcases for cylinder charging.
 
Somewhere on this forum there is a build of a v-twin two cycle that did run, although I'm not sure for very long. I think the guy used two Cox .049 cylinders. Convention says that separate crank cases or a blower are needed to charge the combustion chamber. I have seen a two stroke v4 that appears to use very close timing on the transfer and exhaust ports. http://www.aaenperformance.com/v4_racing_engine.asp But I have not seen plans for any such engine. I think some enterprising home machinist who can cut cams should do so, and sell them. Then we can just make four strokes.


Sent from my iPad using Model Engines
 
Well, progress has been a bit slow due to work commitments and such. The timing case is coming on slowly but not without a couple of dilemmas.
Firstly I was a little over zealous with the feed on the bridgeport and the part was wrenched from the dividing head. Luckily no real damage was done.
Next was a broken drill in the mounts for the tappet guides so I drilled a further 2 holes each diagonally as only two are in fact used. As it happenes, the drill was push back out when milling the cavity for the cams/gears. :)

timing case.jpg
 

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