FTFC21 - Seaplane Design & Build by Leaded50, Yokosuka 12-Shi Special Flying Boat (H7Y)

DinosEatPeople1

Elite member
how do I align the formers? so that they are at the right distance and at the right angle. also, if I cut rectangles, the skins do not fit. for now I got some kind of nose done, but do not like it. I use barbecue skewers for alignment. how can I make a tail and wing for it? they are supposed t be non master series, btu need to be as strong as possible.
To answer most of that use a big 3 view for reference or possibly put more of a skeleton on the inside like @leaded50 and use paper to test the foam. Like wrap it around the formers and you may need to trim the formers down if you go just off of the paper.
 

FlyerInStyle

Elite member
oh ok. I think I can find balsa plans, as my plane is very similar to the cessna 208. where can I find good balsa plans?
 

FlyerInStyle

Elite member
best plan I could find. can you please help interpret it and find the formers. all the others on aerofred are 3 views. will take a look on outerzone on outerzone only the same plan
 

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leaded50

Legendary member
I am sorry that you are sick, but thanks or all your help or me. could you please make a quick guideline of about 10 simple steps in order to make a master series style nose, like for min. thanks for everything, @leaded50
- you understand i then need build nose part my self, in the scale you want? As said before.. following FT videos on Master builds, and my thread : my-way-of-scratchbuilding-from-ground-up , you would seen how ro do it.
I can make it, but not at moment, it must be sometimes it fits to do it. Its no "10 easy step" more than what i show in that thread, by maked internals, paper & light to find how the skins must look to fit.
 
@FlyerInStyle you've got to cool your jets. Have you built a couple FT planes yet? Do that.

You'll want to find a computer program you can do drafting on, preferably free. Search around for a plane that'll work for you. Draw it up mostly square-ish. Forget about master series for now. Think about it as you go. You're smart enough to draw it up and figure it out as you go. Use all that you learned from the FT planes you built.

Print it, build it and fly it.

There's more than five steps to follow right there.
 

FlyerInStyle

Elite member
@FlyerInStyle you've got to cool your jets. Have you built a couple FT planes yet? Do that.

You'll want to find a computer program you can do drafting on, preferably free. Search around for a plane that'll work for you. Draw it up mostly square-ish. Forget about master series for now. Think about it as you go. You're smart enough to draw it up and figure it out as you go. Use all that you learned from the FT planes you built.

Print it, build it and fly it.

There's more than five steps to follow right there.
so ffor building square planes, I should just take a 3 view of the plane, draw it out at the scale I want, and then glue it together. ok good idea. will try, except that, for example with my modded tiny trainer, I had a problem. I reinforced the nose, but then I crashed it, and all the impact went to the tail and it just snal=pped at the joints. the hot glue/ epoxy thtat I used did not work. what is the best way to reinforce those edges against that?
 
so ffor building square planes, I should just take a 3 view of the plane, draw it out at the scale I want, and then glue it together. ok good idea. will try, except that, for example with my modded tiny trainer, I had a problem. I reinforced the nose, but then I crashed it, and all the impact went to the tail and it just snal=pped at the joints. the hot glue/ epoxy thtat I used did not work. what is the best way to reinforce those edges against that?
Follow these five steps:
1. Build another, the same or different, and do it better this time.
2. Fly it until you crash it.
3. Build another, the same or different, but do it better this time both in the design and the build.
4. By now you really need to be drawing these on the computer.
5. Build another, the same or different, but do it better this time both in the design and the build. You'll be surprised how much you improve in your plane designing, including structural aspects, and your build techniques and the build standards you're holding yourself to.
6. Your flying is improving at the same rate.
7. Nobody's going to give you a five step instruction manual to do this.
8. You'll need to be learning the computer drafting program as you go.
9. This isn't going to happen by Friday.
10. I added five steps.

Now let's get this off Leaded's thread.
 

leaded50

Legendary member
last skin gets on :)
DSC_0790.JPG
 

leaded50

Legendary member
The nacelles are in progress too. The motormounts are placed in the nacelles to fit my used motors, exact 28mm from front. That gives me a 3mm opening to prop. For other motors, this need adjusted if want such small gaps. Mounts are fiber reinforced kind of plastic. :
DSC_0791.JPG



how the nacelles "get skinned" (underside)
DSC_0792.JPG
 
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leaded50

Legendary member
Because the motors planned used (ZTW 2208) and the nacelles are pretty "tight" i dont have space for a X-mount. Dimensions should even been a touch smaller if "perfect scale". Motors are mounted with screws from rear, and also the ESC´s are gonna be in nacelles. Thats why not fully closed yet.
Also here, its easy see that to make prototype can give some changes in later developed plans. Just look at where the rear fuselage meet wingskin, in plans its a more smooth transition traced .
Wings got approx 2.5-3* incidence at root, and approx same opposit degree washout at tip. What i found in my "studies" around flying boats are that a few degrees incidence on wings are good, for easyer take off, more floating over water landings, eg. specially on a plane like this, with less degree changes in fuselage from the "planing surface" (at first step in hull) to tail.

DSC_0793.JPG
 
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leaded50

Legendary member
im pretty much ready with the building, mostly sanding/finish/detailing and electronics back. Its gonna be morer work here, because needed use the "other type" foamboard mentioned before who dont have a typical paperlook on outside, when alufoil is teared off eg... more a "fibrous flossy paper"
Plans too are close to ready, i think is only the canopy back to do.

Here is a view from underside how it looks. When i buildt it, the hull parts wasnt close enough at center, thats the line showing. On plans, this are not the case.
The "bottom hull boards2 at front, can be difficult get shaped right, because it curbes as an "inverted U" to sides, and also up as an "U" a bit in front. The way to fix that, is to "reverse" the foamboard skin... remove outer paper, and let paper be on inside. Its not as wide and unsupported anyway, and if uses woodglue as i do , as reinforcing/clousure of waterleaks, it will gain layer for enough strength on the outside.

Now started the treatment on the plane, sanded edges, makin transitions between eg panels, fuselage/wing and such, before treatment with thinned down waterproof woodglue, sanding again, and some superlight wall filler, before whole plane gets another treatment with waterproof woodglue. .

DSC_0794.JPG
 
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im pretty much ready with the building, mostly sanding/finish/detailing and electronics back. Its gonna be morer work here, because needed use the "other type" foamboard mentioned before who dont have a typical paperlook on outside, when alufoil is teared off eg... more a "fibrous flossy paper"
Plans too are close to ready, i think is only the canopy back to do.

Here is a view from underside how it looks. When i buildt it, the hull parts wasnt close enough at center, thats the line showing. On plans, this are not the case.

Now started the treatment on the plane, sanded edges, makin transitions between eg panels, fuselage/wing and such, before treatment with thinned down waterproof woodglue, sanding again, and some superlight wall filler, before whole plane gets another treatment with waterproof woodglue. .

View attachment 198114
Badass.
 

leaded50

Legendary member
one of trouble with water, is that it can ruin stuff.
To ensure more protection against water, some extra stuff is made.
Look at front of the "horizontal internal spar.(blue arrow)... it meet the former in middle with opening at sides... overwater will drain down to lower hull, and then can take more leaks and prevent eg. battery get soaked as easy.
DSC_0796.JPG


Since the canopy also are hatch for battery, eg... splashes of water that can flow over fuselage shouldnt easy come in. The whole opening have a raised edge at inside of fuselage opening for the removable canopy. Water then needs come on top of fuselage, pluss go up (!) inside hatch/canopy who have a tight fit against fuselage/raised edge, to let water inside. Doubt happends, after earlyer experiences.
DSC_0795.JPG
 

leaded50

Legendary member
Canopy hatch: Lip in front that goes under the forward skin and secures it will not lift on any matter in front., here will the raised edge on opening decide where the canopy is placed forth-back. I also reinforced the lip, and mount with woodglue, as also the underside of fuselage it connects too. At rear i will install 2 magnets (10 x 1mm ) who is strong enough to keep canopyhatch tight against the fuselage, i used a reinforcing and a posterboard here, but could used foamboard... it was just easyer to get it fit at moment.. By making canopyhatch of 5mm foamboard its material enough to sand rounded edges on top/sides.

After painting,eg. windows will be highlighted by use of adhesive chromefoil.
canopy_hatch.png
 
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