Savoia Marchetti S55X 1933 Twin Hull Flying Boat

Wingnutz · December 21, 2014, 01:35:21 PM

A belated reply to an intriguing thread. spurred by seeing a swarm of S55s in the DVD Porco Rosso (should be required viewing for all Italian seaplane fans). Simply wanted to post my agreement with Jack and Rob based on the aileron servo mounting on my Sebart Macchi MC72. Slight twist on the usual servo in the wing configuration. This model uses a low profile, waterproof servo mounted with the drive shaft face of the servo exposed and the servo sealed into the wing with silicone.

bweaver · January 03, 2015, 06:11:47 PM

The construction finally continues!

I have constructed the two booms and elevator stabilizer. They have been attached to the twin hulls after making a foam wing and tail surface incidence template to guide this step.

The elevator and 3 rudder/vertical stabilizers will be attached next, once I have finished attaching the hinges. Then I will attach the elevator with hinges as well.

I see what a number of you meant, when it was said that this aircraft is likely to be tail heavy.

As you can see from the photos, I have lots of room in the hulls to mount batteries and servos to counter this problem. What do you think?

Bruce

Papa · January 04, 2015, 10:33:08 AM

Looks great Bruce. Dry fit your servos and batteries just to be sure but it looks like lots of space. Weight distribution should be no problem unless you put servos in the tail. The twin motors on top will look very smart if you go that route otherwise one tractor motor up front and a dummy free wheeling prop in the rear might work.

Jack.

sihinch · January 04, 2015, 01:02:20 PM

Looks fabulous Bruce. Really taking shape.

bweaver · January 11, 2015, 02:19:12 PM

No one can call me a fast builder. As a matter of fact, no one has ever said that or is likely to say that about me in this regard, or any other.

As you can see from the photo, I completed the control surfaces and temporarily installed them.

I have also cut the aluminum motor mount pod which has yet to be bent and covered both sides with 1/16th inch plywood. Once that is done I can secure it to aircraft and proceed with planning and finalizing the motor(s) and ESC installations and cowl for the motor mount area. I believe this will be best the place for air cooling the ESCs as there will be room between a front and rear motor to secure them in this vicinity.

I can also proceed now with the aileron servo installations and make water tight compartments for these in the wing (bottom). I can also rough in the servos and control rods for the elevators and rudders. I plan on securing the elevator and rudder push rods adjacent to the inside of each of the booms. The three rudders are going to be linked together for control movement purposes and pushed from one rudder at the side.

Once this is done I can finish covering the wing and finishing off the hull construction as well. I will have to build a water tight compartment(s) and hatch(s) for the electronics and battery(s).

Anyway, that's where the project is so far. A little progress is better than none at all.

By the way, I am having a great time reading all the other construction information that is posted in the forum. What a great resource and a tremendous source of encouragement. Everyone, keep up the building.

Any suggestions on my project are welcome.

Bruce

Papa · January 11, 2015, 03:33:07 PM

Hey Bruce I think this is a unique build thread and i enjoy it immensely. I love models with character and this one has it in spades! Building fast or slow is not an issue. Even building skills are not an issue. We all build to our own level of skill and it's not a competition. The only question is "are you having fun"? If you answer yes than all else is of no importance. If you answer no, find another hobby.

Michael builds fast, Colin builds slow and is anal about detail, Robert builds medium fast but has a thing about good woodwork and proper joinery. The one thing they all have in common is the huge smile on their faces when they talk about their current build. That's the secret so you are right on track and believe me an awful lot of members envy your building skills and wish they could do the same. Little do they know that starting is the hardest part and it gets easier as you build.

Jack.

bweaver · January 18, 2015, 11:47:32 AM

I have to bend the motor mount aluminum pod precisely before mounting and attaching it to the aircraft. Does anyone know how to bend sheet aluminum precisely without using a sheet metal brake? Or, does anyone have a sheet metal brake or know anyone that does sheet metal fabrication?

Bruce

Papa · January 18, 2015, 12:32:06 PM

If you use a sheet metal vice-grips like this with a vice you can do some pretty neat bending. Jack.

bweaver · January 18, 2015, 01:23:10 PM

Great Jack. I can see that that will work for me.

Bruce

Papa · January 18, 2015, 02:08:56 PM

http://www.leevalley.com/en/wood/page.aspx?p=66804&cat=1,43456,43407

http://www.leevalley.com/en/wood/page.aspx?p=32011&cat=1,43456,43407

Hi Bruce. I forgot but I have this metal bender from Lee Valley and it is very accurate for our kind of work. I also found their sheet metal vice and it may be a better quality than the vice-grips.

Jack.

piker · January 19, 2015, 10:09:26 AM

I'm with Jack on this one (for a change

)

Bruce, your building project is progressing nicely, and it will be a fabulous scale model when finished. I'm really looking forward to seeing it fly!

bweaver · January 19, 2015, 03:58:33 PM

Thanks guys, I will be going the Lee Valley route for the sheet metal bender. Bruce

bweaver · January 22, 2015, 02:32:29 PM

I have bent the aluminum motor mount pod, drilled the mounting holes into it and glued the plywood framing pieces to each side as well.

Upon reviewing the drawings, there appears to be sufficient room for mounting two electric motors and perhaps installing the two ESCs in the cowl space provided.

Papa · January 22, 2015, 03:07:46 PM

Looks great Bruce. It's so unique, I love it.

Jack.

bweaver · February 23, 2015, 06:57:54 PM

I have turned the heat on the gluepot, which has made me get off the pot and proceed with the project.

I have decided to keep it simple and use only one tractor motor and ESC with a dummy pusher propeller. Now that I have decided this, I have modified the hull bulkheads to accommodate the batteries and wiring. The servos and control rods are installed.

The plane should end up weighing between 2.75 and 3 lbs. It will be powering with a G10 and two 3 cell 1000 mah batteries. One battery will be installed in the front of each hull for CG purposes.

I have been tinkering with using a tallboy beer can for engine cowling purposes. We will see where that gets me.

Next will be finishing the wing covering and hulls. I have to make a battery hatch for each hull and a hatch under the motor mount pod in the cockpit area for access to the electronics.

Taking one step at a time.