vivillik

I'm starting to build HVP-modells Catalina PBY-6A seaplane.

I am planning to use 2x Graupner Speed 480 motors and 3S LiPo batteries, here are my questions:

1. What would be the correct size for 3 blade propeller ?" x ?" (6" seems to be the maximum)?

2. How much mAh should there be in the LiPos to achieve appr. 15-20 min flight time?

captfirefox

Hope that you are still in contact with RC Universe / I have an HVP Catalina PBY-6A and plan to construct it this year / How is yours going ?

quenda

Hallo!
I'm very interested at the HVP Model Catalina.......some vendors in Germany have still some boxes.
It coould be my first seaplane and I have many questions....

Removeable wing for storage and transport??

Weight??

Overall quality of the kit and instructions??

How about the motor mounts.... they have the correct angle or I have to find it by myself??

That's all for now....I'm very courious!!!

Thank-you and sorry for my english!!

ettore (from Italy)

r_kopka

Wing is removeable (two bolts)

With 8x GP2000 about 1400g; 2x PRO480 with Graupner 6x4 do fine.

Good quality. Sufficient instructions.

The given angle of the motor mounts is OK for me.

No problem with construction. Only small nuisance: there is only a relatively small opening under the wing through which you have to get the servos mounted and serviced. It't a bit challenging and not for someone with XXL hands :-) If you use Lipos which are lighter and must get further to the front you might put the servo board more to the bow (may need new linkages).

The opening hatch in the front is very convenient for access to the battery.

RK

quenda

Thank-you Kopka for the useful informations!

At this moment I'm trying to find what will be the final cost for the HVP Catalina.

I'm worried about the total weight of this HPV Cat.....and I'm thinking at 2 brushless motors with 2 ESC and a li-po battery.

Unfortunately with this setup the total cost will be high.

Can I use two inexpensive "made-in-china" BL motors like the TowerPro 2408-21 (or similar...), instead of the heavy Speed 480 motors, on the HVP Catalina ???

What kind of finishing do you have used on your Catalina: iron-on film or glassing??

Of course if you have some photographs of you Cat, it will be great....

Grazie mille!!!!

ettore

r_kopka

There is no reason not to go with cheap brushless. Even if the BL are a bit heavier than an expensive AXI(or similar) they will still be lighter than any Speed480. And the efficiency will be good enough. We have reached a point where you can buy a BL combo which is nearly the same in price than a brushed solution. At least if you calculate a gearbox. I just made some calculations for a project of mine.
On the other hand for a model like the Catalina (150cm) with Lipo PRO480 will just do fine. No real need to go BL. In any case you should use two ESCs.

I used Iron-on film. The finish is not finished :-) And I still want to add controlled wingfloats.

[link=http://www.kopka.at/modell_f_wasser.htm#Catalina]http://www.kopka.at/modell_f_wasser.htm#Catalina[/link]

RK