PZL 62 + Baby Bee

HS65MG seems to be a 12g servo (also quite pricey, ouch). Will one be enough for both ailerons or do I need a separate one for each?
Sadly, I haven't found any description on how to choose the right servos for a plane.

dirk gently wrote:HS65MG seems to be 12g servo (also quite pricey, ouch). Will one be enough for both ailerons or do I need a separate one for each?
Sadly, I haven't found any description on how to choose the right servos for a plane.

Yes it will be good for both ailerons.

dirk gently wrote:HS65MG seems to be 12g servo (also quite pricey, ouch). Will one be enough for both ailerons or do I need a separate one for each?
Sadly, I haven't found any description on how to choose the right servos for a plane.

Servos aren't good area to try to save money in Dirk.
When I made the Bacaruda which even with me 'tweaking' the plan is only 15.5 ins wing span and weighs a few fag papers.
I thought "naw need for decent servo's" and put 2 5grams in.... first bit of 'spirited' flying led to rudder servo siezing and the resulting bumpy 'landing' (OK arrival) stripped the other one as well. I could have just coughed up for the HS50's in the first place.. both of which have now had a couple less than smooth landings and seem fine.

And yes always 2 aileron servos it's not 1975 any more, less trouble to instal, more direct control and if your'e TX is progamable the sky's the limit.
J

John Goddard wrote:

dirk gently wrote:HS65MG seems to be 12g servo (also quite pricey, ouch). Will one be enough for both ailerons or do I need a separate one for each?
Sadly, I haven't found any description on how to choose the right servos for a plane.

Servos aren't good area to try to save money in Dirk.
When I made the Bacaruda which even with me 'tweaking' the plan is only 15.5 ins wing span and weighs a few fag papers.
I thought "naw need for decent servo's" and put 2 5grams in.... first bit of 'spirited' flying let to rudder servo siezing and the
resulting bumpy 'landing' (OK arrival) stripped the other one as well. I could have just coughed up for the HS50's in the first
place... both of which have now had a couple less than smooth landings and seem fine.

And yes always 2, less trouble to instal, more direct control and if your'e TX is progamable the sky's the limit.
J

J with my rainbow it will be 3 metal gear servos 5g each maybe got for 12" WS and a but less dihedral. No ailerons, rudder, elevator and guess what the other servo is for

nitroairplane wrote:

John Goddard wrote:

dirk gently wrote:HS65MG seems to be 12g servo (also quite pricey, ouch). Will one be enough for both ailerons or do I need a separate one for each?
Sadly, I haven't found any description on how to choose the right servos for a plane.

Servos aren't good area to try to save money in Dirk.
When I made the Bacaruda which even with me 'tweaking' the plan is only 15.5 ins wing span and weighs a few fag papers.
I thought "naw need for decent servo's" and put 2 5grams in.... first bit of 'spirited' flying let to rudder servo siezing and the
resulting bumpy 'landing' (OK arrival) stripped the other one as well. I could have just coughed up for the HS50's in the first
place... both of which have now had a couple less than smooth landings and seem fine.

And yes always 2, less trouble to instal, more direct control and if your'e TX is progamable the sky's the limit.
J

J with my rainbow it will be 3 metal gear servos 5g each maybe got for 12" WS and a but less dihedral. No ailerons, rudder, elevator and guess what the other servo is for

I'm not sure about less dh Big Guy. I increased the W/S and reduced the DH by a 1/4 inch which is probably why it spins so
easily, I'm sure if I'd left alone it would be a little more docile. Mg not needed for the throttle but if you're gonna pratice Arriving instead of landing as I've been know to do...
not a bad idea.

Tell you what I did end up doing.. that was to put rudder on the aileron stick.

I always put rudder on elevator stick if I am not using ailerons.

I ordered balsa. While waiting for it to be sent, I drew 15% thick wing airfoils to use as templates for cutting the ribs.

dirk gently wrote:Ok, so now I'm thinking - 1.5mm (1/16in.) sheet balsa for the fuselage probably won't be enough? Should i go for 2mm? The construction method will be as in the LA Stick - no longerons, just sheet balsa sides.

Also, for 65cm wingspan I was assuming a 5g servo for the elevator, and a single 9g servo to power both ailerons. With about 80cm wingspan, that ain't gonna cut it, right?

If you're building a larger version for the Babe Bee as you say, 3/32" would be quite thick enough for fuselage sides, as long as you pick medium grade.
Only comment I'd have after looking at your plans is that I'd do away with that built-up rudder, from the amount of bracing you show on it you might just as well use solid balsa, and it would be lighter too, last thing you want is extra weight in the tail.
If you ARE building the 33" or whatever span version, remember that it is still a "Small" model, being scale you do not have the wing area of a non-scale model of the same size, so you will still need to watch how much weight you are adding as you build it, keep everything as light as possible, and make doubly sure that there are no warps in the surfaces before you attempt a flight. My opinion, for what it's worth, is that you are pushing your luck building a low wing scale model as a first model. In my days running a model shop I spent a LOT of time convincing beginners not to try to build a Spitfire as their first ever model!

Wilf

Thanks, Ivanhoe!
The rudder construction was just a rough sketch, I don't intend to actualy build it that way, I will do it out of solid balsa, as you said.
It will not be my first ever model. I built a wooden glider before (pine and basswod, tissue covered an doped), and I'm just finishing a styrofoam electric powered trainer. I also have a modeling club in my neighbourhood (actually, I was surprised to learn that there are a number of them in my city) so in case of any problems I will seek assistance there. With their help, and yours, of course, I think I can pull it off.

dirk gently wrote:Thanks, Ivanhoe!
The rudder construction was just a rough sketch, I don't intend to actualy build it that way, I will do it out of solid balsa, as you said.
It will not be my first ever model. I built a wooden glider before (pine and basswod, tissue covered an doped), and I'm just finishing a styrofoam electric powered trainer. I also have a modeling club in my neighbourhood (actually, I was surprised to learn that there are a number of them in my city) so in case of any problems I will seek assistance there. With their help, and yours, of course, I think I can pull it off.

Joining a model club is the perfect way to get on in model building and flying, not only for help but for the company of like-minded people, it's far more fun than going it alone!
The biggest advantage is if you can get an experienced pilot to fly your model for it's maiden flight, he'll be able to trim it out for you and if there is a disaster he'll have a better chance of recovering without wrecking the model! I really wish I had a suitable club locally, unfortunately I live out in the middle of nowhere, and the only club within reach is R/C only and VERY expensive to join.

BTW, being aware of scale restrictions with respect to wing area, I made the wing slightly larger than it would be according to scale.

I reconsidered the choice of airfoil, and decided to go for Clark Y.

The mailman brought me my balsa yesterday
Now, (I'm sure someone thought of this before), I will transfer the plans onto balsa sheets using a laser print and an iron, pretty much in the same manner when making printed circuit boards.

dirk gently wrote:I reconsidered the choice of airfoil, and decided to go for Clark Y.

Not a bad choice Dirk.
If you wanted to make it a little more 'safe', twist a little washout into the wingtips.

How do I do that? With tissue and dope I could just secure the wing to a wooden board, and once the dope is dry the wing would retain the washout. I'm not sure how to reproduce this procedure using film cover.

dirk gently wrote:How do I do that? With tissue and dope I could just secure the wing to a wooden board, and once the dope is dry the wing would retain the washout. I'm not sure how to reproduce this procedure using film cover.

In the (very distant) past when I've done it I used to do it when building the wing ie when it's pinned to the building board
just put blocks of say 1/2 inch (or whatever) under the trailing edge at the wingtip then glue it all together.
However as I've intimated before I am no bulider and I'm sure once the boys in the States wake up they'll chip in with their ideas.
As for film I have used a heat gun to remove warps from artf wings so I'm sure you'll be able use that method BUT I'd
say that they may not hold the same 'warp' each side which building it in will/should.
Besta luck
John

Today, I glued some pieces of wood together: bulkheads, stringers, balsa doublers and a servo shelf:

https://2img.net/r/ihimg/photo/my-images/843/dscf2185q.jpg/

I also cut out fuselage sides:

https://2img.net/r/ihimg/photo/my-images/28/dscf2186m.jpg/

My Kavan ART26 tank extender turned up late last week Dirk which if my schoolboy Maths is close adds 5cc fuel capacity.
I'm gonna try it out on my Christmas Bee to see what we got, time wise.
It may be the sort of thing you need.
I know Mouse racer Paul on here has got one.

John Goddard wrote:My Kavan ART26 tank extender turned up late last week Dirk which if my schoolboy Maths is close adds 5cc fuel capacity.
I'm gonna try it out on my Christmas Bee to see what we got, time wise.
It may be the sort of thing you need.
I know Mouse racer Paul on here has got one.

lol cool if it goes well I may have to get one for my Xmas bee.

Yesterday I glued most of the fuselage together (photos to come).
I am wondering if it would be easier to build wooden wings with ribs and all, or just cut them out of styrofoam.

The foam will be heavy compared to bulit up.

I just calculated that it will be somewhat above 50g (not counting carbon spars) assuming foam density of 30g/dm^3.
I will stick with balsa and pine spars then. Thanks.

John Goddard wrote:The foam will be heavy compared to bulit up.

I bought myself a scale today.
the wing of my trainer RC plane (80cm wingspan), styrofoam and carbon spars weighs 38g.
the wing of my glider(75cm wingspan, but higher aspect ratio, so the overall wing surface much smaller than the trainer): basswod ribs, pine spars and edges, covered with japanese tissue and dope weighs 51g.
Seems that even if I cover a foam wing with film, I will still be in the same weight range as in build up wings.

So far my almost complete (but not covered) PZL.62 fuselage weighs 48g. I don't know if that's good or not.
The hardware will add 100-120g, and the wing, I guess, around 50, probably 20 for the stabilizers, I think should fit into 300g, perhaps even 250.