Originally Posted by MaceH

You can always run thin ca into the elev horn slots from the other side of the surface- they go all way through- make tiny slit in the covering and squirt some in. In fact that is stronger than epoxy because it soaks outwards into the balsa.

Thx a lot for the advice, will do it like this.

Hi guys,
Just finished my baby with OS GT33 but I have a small problem. Seems that with the CG at 5.5" as is written in the manual is tale heavy and I have to go like 6" and something. I have Savox 1256TG in the plane including throttle, with 2 packs of 2200 2S for receiver and 3000 for ignition. I did the CG with the tank empty is 500CC. So for those with OS GT33 how it went your CG? and for the rest with gas engines in the range of 33 CC capacity how you managed the CG? If at this point in time it is around 6" I think I should not fly it like this right? Even if I saw that most of you guys said that 5.5" as is in the manual is nose heavy.
Thx,
PS> I am looking forward to not add extra weight and try to play as mush as possible with what I have inside the plane.

Balance it according to the manual. Mine is electric and I had to put the batteries in the motor box. The V2 is a little heavier in the rear than the V1 so you may need to move things around vs someone else's build.

I'm about an inch behind the rear edge of wing tube- flys hands off right side up and inverted, really perfect. My manual's position left me very very nose heavy. I have a 'V1' I think; at least, it is certainly not a V2.

Rudder authority for me was quite poor so I extended the thing a few inches... not a lot of work and I think worth it. Adds <1oz which I needed anyway to balance. Pop tops are much much better now as are knife edges and ke spins.

Its a 1/16" ply frame with lightening holes ca'd into a dremeled slot it the existing rudder, with some balsa sticks for the white moneycote to adhere to. Was helpful that the existing rudder had such a thick trailing edge so the airfoil is still quite good.

Thx guys for your reply. I did not had the cowl mounted, my bad , which is 160 grams,. so tonight as I finished mounting the cowl, will do the CG again to see where I stay bout it should be fine with this extra weight.

whats the main difference between the electric version vs the gas version?

I have a guy selling the gas version but I want to convert it to electric,..

Hi guys,
Finally my baby went high in the sky J, WOW, I love it. First videois with the maiden flight ( from minute 4:30, till that time I was just tryingto start it and the guy was doing some adjustments on the radio for throttlecurve) but the engine was only one tank run at the ground so was not properlyadjusted so only in the 2nd movie the engine is after 2.5l ofgasoline properly adjusted ( let me know how it sounds ok to you ), it is abeast J,almost 3l of gasoline in 2 days with OS GT 33. Surprise is that with CG at 6.19inch ( manual says 5.5 “ ) it is nose heavy so need to do some adjustments,tank is 500 ml after CG. I have 2S 2 Lipo 2200 for receiver and for ignition3000 mah 2s, need to move them, for those with more & less configuration ifany suggestions where the right CG should be just let me know. And here comethe surprise with OS GT 33 L,when I was trying to start it for first time it was getting out some gasolinethrough the reed valve assembly, I have checked properly before so just wentwith tightening the screws but either the valve was broken in 3 pieces alreadyor did it from tightening the screw too much so the engine did not startedafter anymore till we have put some epoxy and added a handmade gasket soeverything was fine after but immediately after we started the engine, a new crackcame on the big piece now, initially the cracks were on the small piece ( seebelow link and you will understand what I am referring at. Even with the crackon the big piece of the reed valve it seems that it flies without problems,will try to find to buy this but seems nothing in stock in Europe stores somight need to order it from USA. Overall the plane is a Beauty, with CG adjustmentsand changing the reed valve assembly of the engine will be happy J and fly it everyweekend.
http://www.amazon.com/ENGINES-283160...ct_top?ie=UTF8

Extra 300 78" V2 OS GT33 Maiden Flight (8 min 51 sec)

Extra 300 78" V2 with OS GT33 (1 min 14 sec)

Good job Bogdan... and curious to know how the reeds broke. I can tell you that it takes very little torque on the bolts to keep the carb on the engine so don't overtighten those.

I've seen that reed block on another engine- RCGF I think- I'd get genuine OS if possible but I'm pretty sure it is a generic part, maybe you can find it locally? That is a good thing about the Walbro carbs, for that size carb, most all the reed blocks are interchangeable- and good luck finding one that will work!

Seems that I was missing the two gaskets that are being mentioned in the manual from below link so that's why the gasoline was getting out, when we tighten the screws initially only a little bit, it was still getting out the gasoline so we did it again more so seems that after it happened, how is it possible to crack it still do not understand as this piece should be solid enough and not crack in 3 several part. Tried to find this at our local stores but in Romania rc hobby is at a very low level and we order usually outside the country so will look after RCG/DLE/DLA in case the guys will not answer from lindinger.at from where I took the engine. Wrote an e-mail to OS guys as well. Let's see. At this point in time engine is working as only one crack I still have it no repair, is the one from the big piece of the reed vavle, maybe I can put some epoxy to be sure that no air will get out from there. Will keep you posted.
http://www.amazon.com/ENGINES-283150.../dp/B007KN1ILK

http://www3.towerhobbies.com/cgi-bin...?&I=LXBXTX&P=7

If all else fails- pretty sure Tower ships internationally.

Yea, it has rubber bits that squish so that the thing won't break.

Placed the order yesterday and today was shipped, waiting for tracking number and hope will have this as soon as possible, took 2 pieces from each to make sure I have a backup. Off-topic question as I see the OSGT33 topic is not very often checked. In the manual OS says that at 50% throttle 70-80% of power is developed. If for example I am going for a 11 minutes flight mostly with the throttle at 50% which will mean what I said above, can this affect the engine? I suppose not. Fact is that I am a beginner in gas engines and need to understand this. Usually for 10-20 flights I fly a new plane kind of standard, one roll, inverted a little bit and nothing special so I get used, that's why even management of throttle is kind of a low level in the sense that I am not going very often down, up, etc., just keeping more or less the same at 50%. Thx for answering and sorry if my question is a little bit stupid. Did this weekend another 3 flights of 11-13 minutes each, what a baby, it flies absolutely perfect, I love it.

Receive it and installed and went to fly . Everything works good. Here is one of the flights I took last weekend. What I still need to do is to find the right CG as for now is nose heavy and once I mount the cowl as well will be very nose heavy.

Aeropower 2015 Bogdan Motrici (5 min 6 sec)

Fun stuff Bogdan. Thanks for the video!

Originally Posted by bogdan.motrici

Placed the order yesterday and today was shipped, waiting for tracking number and hope will have this as soon as possible, took 2 pieces from each to make sure I have a backup. Off-topic question as I see the OSGT33 topic is not very often checked. In the manual OS says that at 50% throttle 70-80% of power is developed. If for example I am going for a 11 minutes flight mostly with the throttle at 50% which will mean what I said above, can this affect the engine? I suppose not. Fact is that I am a beginner in gas engines and need to understand this. Usually for 10-20 flights I fly a new plane kind of standard, one roll, inverted a little bit and nothing special so I get used, that's why even management of throttle is kind of a low level in the sense that I am not going very often down, up, etc., just keeping more or less the same at 50%. Thx for answering and sorry if my question is a little bit stupid. Did this weekend another 3 flights of 11-13 minutes each, what a baby, it flies absolutely perfect, I love it.

Break in- just don't run lean and not wide open throttle for extended periods. It is actually helpful to run wot for a bit, then let the engine cool. If you never heat up the engine, it doesn't break in much. A 'perfect' break in flight might be to do endless giant loops or cuban eights. OR just fly normal and avoid hovering much lol.

Also not great idea to run without the cowl- the engine can actually run too cool- spark plug may look a little crusty if you do. On the other hand it is good to keep the ignition cool- it'll last longer.