The Tinker bi-plane hangar

[WolstonFlyer]

Good point about the phone BEB, I use mine with headphones that have a little mic built into the wire.

Thanks Danny - I was thinking the same thing about the weight as I was sticking the little ply bits on - the 4 little hard points for the wings weigh almost nothing but the servo / receiver tray is heavier than I would like, I only had the 2mm ply in stock so that's what I had to use. I could cut some quite big holes in it, or cut it down much smaller - it's not glued in yet.

What actually concerns me is the location of the flight battery, I intended to put it under the hatch in the nose but that might end up too far forwards with the motor and ESC up front as well, I don't know how much the electrics compare in weight to the original IC and fuel tank?

I suppose I can leave the final position of the battery tray until quite near the end of the build when I can balance the plane out with the tail and wings and wheels on - or put some lead in the tail

[Dai Fledermaus]

Perhaps I'm being a bit dim, but I don't understand why you have cut away the fuz side to expose F4 and the doubler between F3 and F4. I noticed it in your earlier photos. Is it something you are going to add later?

[WolstonFlyer]

Hi Colin

Nothing has been cut away. The fuselage sides use the full width of the sheet of balsa and the thicker 1/4 inch cabin sides are stuck on the top of the longerons. The triangle gap at the front needs covering over with a bit of 1/16" sheet one the block for the front window is put in place.

I am leaving that until a bit later so the nose area is still open enought to get my big fingers in there

[Dai Fledermaus]

O.K. I was comparing it with other similar DB designs like the Tyro series where the sheet balsa sides, in your case 1/16",  are the full profile of the fuselage including the cabin and the 1/4 doubler, which you called the cabin side, was glued to the inside of it

Edited By Colin Ashman on 21/11/2013 11:31:00

Edited By Colin Ashman on 21/11/2013 11:31:31

[WolstonFlyer]

Ahh ok I see what you mean.

Is the tyro a later design? Perhaps it was changed to improve the strength in that area. The whole cabin and top wing of the Tinker relies on the glue joint... hmm perhaps I should look at that?

[Danny Fenton]

WF this design is pretty old and the one I built many moons ago did not fall apart. I wouldn't worry too much about comparing it to other aircraft, DB knew what he was about Go with the plans and you will be okay

I am not meaning to knock anybody for charging forwards because they are doing a great job, but the idea was to follow along with the more experienced builders. I stuck my hand up to do the Tinker, but I based that offer on us starting the mass build after Christmas. Just an observation....

Cheers

Danny

[WolstonFlyer]

Hi Danny.

I am sure the design is fine, I wasn't worried about it until it was just mentioned and I will carry on as per the drawn plan. Like you said all of the extra little bits here and there will add weight and I do tend to over engineer things sometimes.

Sorry I didn't mean to end up posting my full build pictures on here before you did, I should have done a separate thread.

I am basically a complete beginner and with work and kids I just know how long my building takes so the extra time before Christmas gives me a head start!

I don't want people to think I am posting the best way to do things as you are a very experienced and expert builder, and you did say you were going to do the example build for this model.

I will carry on with mine slowly in the background.

Cheers

[Danny Fenton]

Hi WF, no please don't take it that way, I am thrilled that you are cracking on, it really isn't a problem and please carry on posting. I know we are all more than happy to help you any way we can

It was more a general shout to the Mass build organisers really, not aimed at you

Cheers

Danny

[WolstonFlyer]

Sorry I misunderstood. I am happy to keep posting pictures and asking daft questions as long as nobody minds. I know the mass build doesn't technically start until the new year.

[Former Member]

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[Ken Lighten]

I'm at the exact same stage of the build as you Percy!

Will start proper in the New Year and hopefully be able to add pics as I go, I have put my version of the changes on the plan for the inclusion of ailerons, including the dihedral change using info from DB (1" under each tip for the lower wing and 1 & 3/16" for the upper)

Ken

[Former Member]

[This posting has been removed]

[Ken Lighten]

I agree Percy, I'm doing 4 bays and 2" wide on the lower wing only

Ken

[WolstonFlyer]

I am glad you have posted that info Ken, I had settled on 4 bays (probably one in from the tip I think) but didn't know how deep to make them, I don't have the plan with me just now to measure but 2" sounds good.

[Danny Fenton]

Ordered a PAW 09 (1.49cc) today for my Tinker, now should I build the Bistormer or Tinker first

How are others getting on with theirs?

Cheers

Danny

[Former Member]

[This posting has been removed]

[Danny Fenton]

I hope so, mine will be fairly lightweight being tissue and dope, Eddie quotes 09 - 15 on his web site. So yes it is at the bottom end of the power scale, but hopefully okay. The next PAW up is a 3.1cc (19) I think which will be too much for the sort of flying I want it for. Perhaps a 2cc would have been perfect. We will see, it will be hand launched

Cheers

Danny

[Former Member]

[This posting has been removed]

[Danny Fenton]

I like a challenge the mightier PAW is on its way, if it doesn't cut the mustard its easy enough to replace. Mind you staggering into the air sounds fun
Cheers
Danny

[Former Member]

[This posting has been removed]

[Ken Lighten]

Time to make a start! - it won't be quick tho!

Side sheets cut after butt joining some sheets of 3/32 balsa to obtain the correct width and marked for the two built up frame positions (I can't help thinking that this fuselage design is a tad more complicated than it needs to be, hey, who am I to argue, but I would think it might fox the inexperienced builder a bit)

the rear upper 1/4 square longerons needed to be steamed to shape to prevent building in stresses (its quite a tight curve just aft of the upper wing)

The two built up frames pinned to the board, note the use of a couple of scraps of 1/4 square balsa to ensure the correct allowance for the fuselage side doublers. I have altered the angle of the upper and lower cross pieces on F5 as I am reducing the dihedral due to the fitting of ailerons

to be continued!

Ken

[Darlo0161]

So my plans are ordered and I'm just getting my balsa order ready, I'm pretty confident in my woodworking and modelling skills. I have a couple of questions.

Build Board - I've got a thick piece of Ply and some foam to go over it as a base... I know opinions vary but does that sound reasonable ?

Its my first build....which bit do I do first ?

I haven't ordered my hardware (i'm going electric) yet, should I wait and order before I start building or should I get going ?

I'm going to add aerilons do I HAVE to change the dihedral ?

If I do is it a "complicated" task ?

Thanks as always for responses.

Darlo

[kc]

The building board needs to be dead flat and to take pins. Plasterboard is used by many of us, maybe put a layer onto the ply if it's flat. Plasterboard accepts pins and grips them. Foam would not grip them well but cork would be OK. It takes quite alot to keep the spars etc flat on the board while you position ribs etc. Any movement that loosens the spars will cause a warped wing. I like to hold spars down to platerboard using screws and shaped ply blocks. Make sure the screws are accessible once the wing is sheeted!
Its not difficult to change the dihedral during wing build, near impossible after. Follow what other builders of this model do, both for dihedral and electric motor. You really need the motor at an early stage of fuselage build.

[John F]

As KC says the board needs to be stiff, flat and be able to take pins. The foam would not guarantee a flat surface. I used a layer of cork floor tiles over my board to be able to take pins, other people use plasterboard.

It makes sense to build the model with the actual components in mind, moving some formers to be able to accommodate the size of the servo or motor etc.

I have noted that some folk start on the wings, others on the fuselage. I don't think there's any difference, unless anyone comes along and says otherwise, of course.

This section contains loads of info for electric flight too which might help : **LINK**

[Biggles' Elder Brother - Moderator]

Hi Darlo

Regarding building boards another view that foam won't hack it I'm afraid! Like John F above I use a double layer of cork tiles on a melamine base. Plasterboard is good. You can also use some stuff called "Sundella" - building yards sell it - the model railway lads use tons of it! All of these will give you a firm flat surface that you can pin into and the pins will hold things tight.

Regarding what part to build first - with most models it doesn't matter. Some folks like to start with fuselage (I do), others with the wing. Some even start with the tailplane and fin - which I can see the attraction - get something built quickly at the start sort of thing. If it matters which you build first, for example if the wing has to exist in order to position certain formers in the fuselage, the plan will usually make that clear in a note somewhere. If nothing is said - assume you have a choice!

Finally about ailerons and dihedral. Well you don't have to do anything you don't want to - that's one of the beauties of plan building! But bear the following in mind; lots of dihedral is put into a model to keep it stable in the roll axis. An aircraft with plenty of dihedral will show three traits:

1. If it rolls slightly to the side - it will automatically pick up the low wing and level itself

2. If you put in any rudder it will bank and turn in the direction of the rudder - automatically

3. It will be very unstable in an inverted position - trying hard to right itself.

Now if you have very limited control all these are good things. But,....if you add a full set of controls they can become bad things. You see every time you try to bank the aircraft with the ailerons you will have to fight the model's natural tendency to level-up. In other words - if you keep the dihedral there is almost no point in having the ailerons - the model will fight you all the way. Secondly if you try to put a bit of rudder in - just to get yaw - you will get buckets full of unwanted banking as well - which you'll end up trying to stop by putting in opposite aileron!

So the simple answer is - you can leave it in - but there's not much point in having the ailerons then!

How much should you take out? How long's a piece of string? An experienced pilot could easily fly the Tinker with virtually no dihedral at all. A less experienced pilot will benefit from the bit of extra stability some dihedral offers. I'd suggest halving the amount set up for 3 channel as reasonable compromise and if I was going to move from that point it would be downwards not upwards.

How easy is it to do? Well I've not built a Tinker, but if its a classical DB design there will be some ply bracers cut in a vee shape the hold the wings in position. You would need to recut new ones. There may be a angle template piece for setting the innermost rib at the correct angle - you would need to make a new one. Neither of these are very difficult but do require a few elementary calculations and a bit of care.

BEB