On_Final

I am putting a DP Extra 330L together for a friend and he got a new ZDZ 60RV to power it. It is the latest version of the Extra (Laser Cut). It seems to me that the wood used in this version is thinner that the first generation Extras which results in a lighter plane. The wing has also been moved back about an inch. (Compared it to mine with a Brison 2.4 on it)

My questions are, will the ZDZ 60 shake the Extra to pieces? Will it be way too head heavy? What kind of reinforcement do I need to do on the engine box?

rmh

If the engine is simply setup per mfg - no problems -
Locally we use these engines in models which are very light - and vibration is never aproblem -there are at least six of em flying in planes from 16 lbs to 19 lbs - the shake that does happen is at an idle -and that is simply a thump frrom running slowly.
reinforce?
why? I use only thin ply -but I do triangulate stuff to stop any bending of unsupported sheets -such as the goofy motor boxes used on many ARFS.

jelaird

My Feedback: (1)

I've had to work over the basswood blocks on the fuse sides that supprot the anti-rotation tubes on the wing. Replaced with 1/4" plywood. Good to go!

On_Final

Thanks for the feedback guys.

I have flown my Dave Patrick Extra (original batch) many times and it has held up fine with the Brison 2.4 on the nose. I was just a bit concerned looking at the new version as the wood used is not as beefy as those in the original batch.

I guess I will just go ahead and build it stock except for tri-stocking the engine box area and changing the control rods to 4-40.

mglavin

My Feedback: (31)

You do realize the 60 is a LOT more power than you need for this model and its heavy, compared to what most are using. If I recall your talking nearly a pound more with this power package than something in the 40-50cc range.

On_Final

Mglavin,

Yes, I do realise that. I think a decent 44 to 50cc gas engine will be perfect for this plane. The Brison 2.4 (40cc) I am currently using is a bit underpowered.

Unfortunately, my buddy, whom I am building the plane for already bought the engine. I am hoping that if I use two servos for the elevators in the tail, it would allow for easier balancing. I am pretty sure that if I use pull-pull as reccommended by Dave Patrick, the plane will need serious lead in the tail.

Even then, the wing on this new model has been pushed back by an inch. I might still need to add weight.

Anyone out there tried this plane/engine combo? How did it balance?