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Mark's Ballerina MK1


Mark Elen
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Some more done in the last few days, With the wings now both at the same stage, it was onto making up the plates for the servos. These are the mk2 versions - I was planning on using standard servos on 1/8 plates, but, having made up the plates, I've decided on mini servos on 1/16 plates. Been out today and got a pair of metal gear Hitec that are half the weight but the same torque and speed as the HS422HD that I was planning on using.

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Cheers

Mark

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Thanks for the generous comments guys.

I've got the engine on a test stand this morning and I'm just a little in awe. All set up, primed, turned the prop backwards till I felt compression, glow on, then to my amazement, the little Saito started first flick backwards.

So, first four stroke, first time trying the 'reverse flick' method and the first time I have ever started a new engine on the first flick. I'm going out now to buy a lottery ticket. wink

Cheers

Mark

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I had a Saito 90 Twin about 30 years ago. A truly lovely engine. I never had any trouble with it and flew it in two or three models.Had to sell it in the end.

I have coverted the Saito 60T ever since it came out but never been able to afford it. One day I will have one but not in this life unless I win a lottery

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Sorry, I should have given you more detail.

My current building plan at the moment is:

Finish, cover and fly the Ballerina.

Start on the next project which is a 72" span Grumman Cougar from the 1980 Dennis Tapsfield plan. The plans for this show 2 off .25 2 strokes as power (shown as os25 Schnurle ported) I'd nearly fixed myself on a pair of SC25s, one reason being the price, the other being they would fit in the nacelles with no modification to the plan.

The only downside to this is the thought of a pair of screaming 2 strokes in what is a stand off scale model. I'm now wondering if a pair of Saito 40s would a) give it the power it needs and b) sound much better.

My concerns are if it is advisable to power a twin using 4 strokes and also the changes necessary to the nacelle to accommodate the longer engine/engine mount (it would need the firewall moving back in each nacelle about 1/2" which would then make the fuel tank bay too short to allow a standard tank to fit.)

One option if the 4 stroke is chosen, is to move the firewall back and construct a custom tank to fit the bay.

As I said earlier in this post, I'd pretty much decided on the SCs but now after running the Saito a few times this morning and it starting so easily and just wanting to run, its got me thinking again.

Any pointers?

Regards

Mark

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Sorry, got the wrng end of the stick!!

I can see no problem with a couple of .40 four strokes. Yes you might need a little more space in the cowl and possibly a fraction longer cowl. In fact you might find that a model that size would be better with the larger props.

I haven't flown a four stroke twin but I see no problems. Get them set up well and that is it.

I have flown quite a few twins with SC engines and absolutely no trouble at all. Funniy enogh they seem a bit less noisy in a twin. My Grumpy Tigercub (SC 15s) goes like a rocket even after one engine stop. IT also is so forgiving that you can turn it into the dead engine with care.

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Tomtom was right regarding the sander, Onetenor.

I went to the RC World website and ordered one when I saw the 'Great planes' sander...

Unfortunately, when delivered it was the "flat bar type"... I should have checked a bit more about the description. Silly me again. blush

So, just ordered one from the US. And I now hope Colin didn't make the same mistake? surprise

Sorry for 'clogging' your thread, Mark.

Cheers

Chris

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Hi Chris,

Don't get me started on tools.... I love em. I always work on the basis that 'you can't do the job without the correct tools' ........

This weeks tool purchase was a servo connector crimp tool to shorten the aileron servo leads so that they fit in the servo boxes without coils of cable and I can still take them out if needed.

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Cheers

Mark

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