Mighty "Mini" PBY-5A Catalina - WWII Flying Boat

[localfiend]

ok thank you. the only think i am worried about is losing the prop nut if i try to do the counter rotating props.

also do you think i could use a different esc? a cheaper one?
im looking at 27 bucks not shipped for just the motor and esc. it might be better to actually go buy 2 other motors and escs that match that are cheaper.

if i go that way should i get similar kv and size motors?

If you tighten stuff down well, you shouldn't lose a prop nut. If you're really worried about it go to the hardware store and get a nyloc nut for 10 cents in the correct size. That won't be coming off without a wrench.

I don't know that I'd want to try a different ESC. Not something I've ever attempted. You'd want to play around with it and make sure it actually spins up and matches the same speed as the other one.

If you can find a set of matching motors and esc's for less than 27 dollars go for it. I've bought lots of cheap junk and had more good luck than bad. And when something fails, it's only foamboard.

When you're browsing for alternate motors weight is probably the most important thing to look for. Aim for something 25-60ish grams apiece. If the KV isn't super high, or super low, it'l probably do the job.

 

[Daniel Kezar]

ok. ive wanted to get lock nuts for a while for my motor but i cant seem to find the thread specification. i think its metric.

 

[localfiend]

ok. ive wanted to get lock nuts for a while for my motor but i cant seem to find the thread specification. i think its metric.

Yeah, pretty much all RC hobby motors are metric. But they're generally the standard thread, I've yet to find a fine threaded motor shaft.

Looks like the B pack motor has a 5mm threaded shaft, so ask your hardware store for an M5 nyloc nut.

 

[Daniel Kezar]

Yeah, pretty much all RC hobby motors are metric. But they're generally the standard thread, I've yet to find a fine threaded motor shaft.

Looks like the B pack motor has a 5mm threaded shaft, so ask your hardware store for an M5 nyloc nut.

thank you!

 

[localfiend]

Greetings Localfiend, i saw the plans you posted on the first page and the thierd , there is few things missing like those small parts inside the tower and the formers and the wing... pls could you email me full plans i really want to build this so bad . my email; fadicvb@gmail.com

Sounds like the download didn't finish or something? I just looked at the links on the first page towards the bottom of the first post. All the parts are there on both the tiled and full size sheets versions of the plans. Beta v.2 is the latest so far.

 

[kilroy07]

I just got back into RC thanks to FT foamies back in Sep '17 and all I have to say is WOW. What a great job! The PDY was always one of my favorite models as a kid (I especially appreciate you took the time to do the framed waist bubbles!) Thanks SO much for sharing such a great design! If I get to flight fest this year first round is on me! (I'll post my build once I get through the other hundred builds on my workbench! LOL)

 

[RavenFly]

Im digging into this as well. Should be fun to get on the water once the ice is gone.

Going to try this with A pack motors. I want to take them off my mini guinea that hasn't flown yet (was a guinea pig for my differential thrust test on dx6i! - tee tee). Avoid buying another set of motors/esc's if i can. Still weeding through the entire thread to see if the float issue was figured out.

 

[Daniel Kezar]

I just got back into RC thanks to FT foamies back in Sep '17 and all I have to say is WOW. What a great job! The PDY was always one of my favorite models as a kid (I especially appreciate you took the time to do the framed waist bubbles!) Thanks SO much for sharing such a great design! If I get to flight fest this year first round is on me! (I'll post my build once I get through the other hundred builds on my workbench! LOL)

first round is on you? first round of what? haha i dont think there is beer at FF.

well i have a similar story of getting back into rc. last september i maidened my ft flyer that i had been working on all year, thus getting me back into rc. (about 6 years before i had gotten a 100 dollar rtf pusher trainer style plane that flew away and that traumatized me out of rc until i started watching ft again in late 2016).

 

[RavenFly]

Some notes on my build so far. Localfiend, not sure if updating the plans is something you want to revisit again or not. If so, I can add a couple more minor notes.

I am struggling to figure out a couple of pieces:

In the wing tower support. Where does part 16 go? Does it wrap around the wing tower for something to glue the posterboard framing onto? . Piece 17 also seems a bit odd, maybe I didnt fold the tower properly, but it didn't really align in the top internal structure of the wing tower support like I thought it should.

Same question with piece 28. I assume that goes inside the wing fold to reinforce over the tower tab points?

As for the wing pylons, I am going to plan to see where it sits in the water and add the Sea Duck pontoons. No issue with them on the duck, and I found the skids on the Otter were not very robust, kept digging in and delaminating.

 

[Keno]

Love this one flew a many times in it and love it. It flies like none other. It takes every air bump as lightly as a butterfly and moves with air currents as they may dictate and yet never faltering. Check out some of its flights from New Zealand during the beginning of the second world war. Beautiful work my friend.

 

[RavenFly]

I am progressing on this - funny building a flying boat in the middle of an ice storm.

The plans have a right thrust angle to them, I think I am going to level it off and have couter-rotating motors. I dont recall seeing anything above on this, but dont recall any thrust angle on my Sea Duck.

 

[Keno]

I am progressing on this - funny building a flying boat in the middle of an ice storm.

The plans have a right thrust angle to them, I think I am going to level it off and have couter-rotating motors. I dont recall seeing anything above on this, but dont recall any thrust angle on my Sea Duck.

Note: Not sure about this but counter rotating props are a great idea and my experience is that it the way to go. I may be wrong but I think the PBY had counter rotating props. Its been a long time and an age since I have been around PBY's. I have the Hobico model and I replace the recommended motors with Emax 2205 motors as they would look more like radials. I made them counter rotating and it proved successful. Although this model does not have good reviews. I think your question should should be addressed to Local Friend as he can surly answer the question better than myself, give him a shout. The PBY is a great air plane and lot of undocumented history as it used in WW2 and there after in civil aviation. It was used intensively in fire fighting.
You take care,

 

[RavenFly]

Localfiend, did you ever settle on how far down the floats should go? I am thinking that they should lift out of the water once the plane is up on the step, so they should be at least just a bit higher than the hull step, but this is really just an educated guess.

I plan to take it to a pool tomorrow to see where it floats and try to eyeball it.

 

[Frits37]

I just discovered this thread, nice read!

To Keno: the PBY didn't have counter rotating props. It was a matter of standardisation: same engines, same props. I have a Dynam Catalina with counter rotating ones and lost a prop due to the threaded axis of the CR motor. After the (active) prop touched the water it came a bit loose and unscrewed itself. The prop sank so I lost it. I changed the direction of rotation an didn't notice much difference in flying characteristics.

 

[RavenFly]

I finally got it out on the water. Nice easy taxi. Differential thrust worked well. Had a little bit of difficulty getting up onto the step as the bow spray went right into the props.

After that it didnt really want to get off the water. My first attempt was a balloon/stall and a plunk back onto the water, luckily with no damage. Second attempt and almost the same thing.

Net result, I am going to put F-pack motors onto it. I put 30A esc's in just in case i had to do this swap, and I think I should have just gone straight to F or B-pack motors. A pack just didnt have enough oomph to get it off the water as easily as I expected.

 

[Frits37]

That didn't look too bad, the landing maybe could have been smoother, but a light plane has little mass and will stop quite abrupt anyway due to the resistance of the water.

 

[miraspen]

landing wasnt too bad, she is a light one. i really like the 2212 2200 kv on the catalina with 3 blade 6045 props. the strut tower is the weak point so make sure you reinforce it as much as possible. Great flying plane. very scale like.

 

[RavenFly]

That didn't look too bad, the landing maybe could have been smoother, but a light plane has little mass and will stop quite abrupt anyway due to the resistance of the water.

Agreed. I didn’t let it settle. Reduced power too quickly and stalled it a foot up. Biggest concerns on my build were lack of power and a twitchy elevator servo/flexing control rod.

 

[RavenFly]

landing wasnt too bad, she is a light one. i really like the 2212 2200 kv on the catalina with 3 blade 6045 props. the strut tower is the weak point so make sure you reinforce it as much as possible. Great flying plane. very scale like.

Going to pick up F pack. TBD on the prop, but like the idea of 3 blade to get them a bit further from water spray.

My tower is pretty strong, and skewers reinforcing the wings are functional - I used really thick ones for just this reason.

 

[cgoffroad]

Almost finished with a scaled up version of this PBY Catalina at 120” wing span.