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6 Turning 4 Burning

A scratch built project,

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PatMc22/01/2020 22:08:31
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4297 forum posts
524 photos

You can see that the rudder is being held over to the left the whole time that the aircraft is taxying. IMO it probably to counter the fact that all props are turning anti clockwise when viewed from the rear which will be causing the aircraft to swing to the right.

Edited By PatMc on 22/01/2020 22:09:02

Denis Watkins23/01/2020 07:31:43
4082 forum posts
77 photos

You can also see that the pilot is a cool customer, and a very adept flyer.

The model is constantly trying to lift it's nose, and appears to prefer a certain track

The pilot overcomes this in a controlled scew appearance.

Has already been said, that with power and squish all along the wing must be unique properties to fly

Erfolg23/01/2020 10:29:56
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11565 forum posts
1274 photos

I was not sure if it was just me, that I thought there were some issues whilst flying. It certainly did not have a rock steady flight path, I have seen with many large models.

I was impressed that he managed to thread the model through the fence opening, when I thought, will it actually fit.

It would not surprise me if there were a couple of church roofs of lead up front, although the flying did not suggest a forward CG.

As for its general performance, I suspect under my control, all would not have gone well. It would have stressed me that it did not appear to be a pussy cat. To the extent I would have been fumbling for the trims, unable to find them, I would have become more stressed and so on. Yep, the pilot did very well.

Trevor Crook23/01/2020 11:42:45
909 forum posts
67 photos

There's a bit of info and footage of B36's in this tale of a mind boggling incident:

https://youtu.be/p0gRHgwSGhE

Erfolg23/01/2020 15:32:22
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11565 forum posts
1274 photos

Not surprised that a bomb was accidently dropped. I seem to remember that some weapons were lost in to the sea of Spain in the past. With every single thing you can think of from weapons to the domestic clothes iron, (almost) every household has, there will be accidents, some you can scarcely believe.

In the Spanish incident, i think the main priority was to recover the devices before the Russians saved them, on behalf of humanity.

In this case we were told that th Pu hemisphere were not in the weapon, as apparently was normal procedure. There could well have been other safety devices that we were not made aware of.

I did like the pictures of inside the aircraft, showing quite a lot of detail.

 

Edited By Erfolg on 23/01/2020 15:34:00

SR 7123/01/2020 17:00:05
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346 forum posts
95 photos
  1. Found somie left over MDF from building my hanger, so i have used it to make the front and rear sections, glued it into the drain pipe20200112_161551.jpg
J D 823/01/2020 17:36:39
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1358 forum posts
78 photos

Drainpipe, MDF !!! Having a Giraffe.laugh

Denis Watkins23/01/2020 17:47:28
4082 forum posts
77 photos
Posted by SR 71 on 23/01/2020 17:00:05:
  1. Found somie left over MDF from building my hanger, so i have used it to make the front and rear sections, glued it into the drain pipe

You are making a FORMER to MOULD the fuselage

SR71

Don Fry23/01/2020 18:26:28
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4413 forum posts
52 photos

We hear about death by planking. Glue the wood together, stick it in a wood lathe, tailstock out, and if you get it straight, a light skin, if you feed it straight. Not the cheapest, but quick. Lot of aircraft, can't mess about.

Erfolg23/01/2020 18:58:25
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11565 forum posts
1274 photos

Denis

I suspect you have got it in one.

This is going to be an interesting project.

I suspect that it meets one of my criterion for a good model, it can be flown in most weather. I am also guessing criteria number two will be achieved, that it will be robust.

I am really interested how the CG issue will be solved without a load of lead.

I have always have had reservations about the model that requires, almost a dead calm, that need careful handling because there is not the power etc. Almost any one can build the fragile floater. I suspect this is another animal.

Don Fry23/01/2020 19:12:56
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4413 forum posts
52 photos

In fairness, Erf, it will balance about the wing. That is where the weight is. The rest is a bit of material in front of, and behind the wing.

A bit of a concern, one of the videos showed a slightly twitching flyer, and a horizontal nodding behaviour, what looked like Dutch Roll. And that is a symptom of marginal vertical stabiliser/rudder area.

Erfolg23/01/2020 20:05:19
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11565 forum posts
1274 photos

Don, I agree with what you saw, I saw the same.

I know the rudder area is massive, I would be surprised if it was or is the issue. The wing is pretty much flat, there being no dihedral.

Although under certain circumstances my canard, does a sudo dutch roll in turns if going slow. Fast no issue.

I think you may be mistaken with the motors and fuel tanks relative to the CG, they are on the wrong side, together with the tail assembly, they need something up front to balance the moments. Assuming that the model is IC, there is only the Rx, a battery and perhaps some fancy electronics, may be a couple of servos?

I am really interested how the issues will be manged and resolved, without lead.

In my mind it could be a big glider, other than the Power Plants and their fuel to mess simplicity up.

Don Fry23/01/2020 20:33:04
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4413 forum posts
52 photos

Not sure about a massive rudder.

I see a reasonable rudder, a short moment to the CG, and a load of nose in front. But something was causing the bloodhound on a track nod.

and Erf, if it was simple, this builder wouldn't bother. I reckon I'm being clever sticking crow brakes onto an Avicraft Panic. Different league.

Erfolg23/01/2020 21:09:10
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11565 forum posts
1274 photos

Don

The moment arms are about 50/50. There is a lot of structure in the Rudder/fin and tailplane.

If you look at a drawing of the rudder/fin it is large. Compared to the wing area, probably something like I would expect, for a sailplane. The B17 had its rudder/fin enlarged due to poor tracking, which was also large.

In essence, it does not matter what I think. although i expect i will learn something form others struggles.

Trevor Crook23/01/2020 22:18:29
909 forum posts
67 photos

I'm not sure I'd agree with the "fly in any weather" design aim, but that's down to personal preference. I like scale models to look scale, on the ground and in the air. As the B36 is so huge, even a large model is going to have a large scale ratio - even a 1:10 scale model would have a 23' wingspan. To look right, this would have to cruise at 30-40 mph and take-off and land at about 10-12 mph. In order to do that, it needs to have a low wing loading, and will therefore be impacted by strong winds. Assuming it's not going to enter competitions and have to fly in all weathers, it could be restricted to sub-10 mph wind days, when it would look very nice.

However, it's not my project, and I could never imagine building such a thing, let alone getting the weight down enough, so I'll just keep watching progress with interest and admiration.

Erfolg24/01/2020 12:08:30
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11565 forum posts
1274 photos

Trevor

You are spot on, what I, or others think, does not really matter. Although the exchange of views has to be interesting.

Coming from a model glider and competition background, it is not unusual to fly them in all weathers. My largest, @144" wingspan has flown in 20 mph winds, my Ridge Rover, +100" span (now stacked away), even my 3m Algebra has also flown in very similar winds. Are they relevant, they are in as much the spans are large with modest bodies, similar to the B36. The plus side they could be landed quite slowly even in dead calm weather. As for scale type speeds, probably pushing it a little near to the stall to be continuously flown as such.

I was thinking about what SR is about to do. I must admit I think he has both wrong footed me, and about to show me a technique I have not used.

In the past I have made my own plugs and moulds, then pulling my own fuzs. Below is a selection I have lying about in a bucket. A pile of tail booms (fishing rod blanks) are in the background.

wp_20200124_09_36_30_pro.jpg

At first I thought he was about to make a female mould from a plug he has started, for the nose and tail.

wp_20200124_09_38_00_pro.jpg

Still having some PVC pipe of the same size SR has shown us, I thought OMG, that is heavy. I then thought it must be a whole fuz.

My experience of making moulds, is that it is very hard work, time consuming, on this scale expensive. For one body, hmmm. He must have another idea.

I am now guessing, could it be a variation on the lost former method. Which I must confess I have never tried. Mainly as I saw my gliders as consumables, although the Earth would scream in agony when impaled by a model. Even then there would often be minimal damage to the model. So how would you do it? lay up on top of a prepared plug, well waxed. The cut longitudinaly. Given the contours it is probable that the shells would pop of, without an incredible amount of effort.

I have however rubbed down GF mouldings to smooth them out, in a bath of water with soap. Both time consuming, and ruins your hands, even with your marigolds on.blush

At the size indicated, as a slope soarer, a lot of the CG issues disappear, As for landing, the real one used barn doors for flaps.

Go on, give us a clue SR 77!

SR 7124/01/2020 21:20:35
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346 forum posts
95 photos

20200117_131208.jpg20200113_161133.jpgDone a little more, started to shape the MDF, very dusty in my new hanger, way to cold outside20200113_154320.jpg

Erfolg24/01/2020 21:33:40
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11565 forum posts
1274 photos

Come on, give us a clue.

I guess you are not using the dust bag, I hope you are using a breathing mask. Even using a belt sander, it must take some time?

Are you using templates? As I cannot see them?

Edited By Erfolg on 24/01/2020 21:35:33

SR 7124/01/2020 23:38:41
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346 forum posts
95 photos

Hi Erfolg there is nothing special about the build, straight forward plug, mould and cast the finished fuselage in an effort to keep it light at the rear end, i hope as i have little experience

im doing it by eye and a centre line along the top of the fuselage, i like to think things out as i go along,look on the internet at all the pictures and films i can find, its not a competition class model, i not good enough for that, i just like building something different to run of the mill, and these things have stuck in my mind for 70 years so i thought it was about time to have a go at one, Before its to late, not my type of flying model i must say as you can only go round and round with it, but i will enjoy the challenge of build

Tony

Erfolg25/01/2020 15:27:00
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11565 forum posts
1274 photos

I did spot the centre line.

I am about to start a small lay up myself, a couple of cowls. What has surprised me, is how much I have forgotten. Another aspect is the small roller tool I used for consolidation was thrown away, on the basis, I will never do any layups again.

I am now busy saving paper cups for my mixes, looking for alternatives to lolly pop sticks for stirring. When making canoes, I could buy big ones from Strand Glass, later i pinched my little girls (who are now middle aged) lolly sticks.

After a lot of thought i have decided on Polyester Resin, as I notice that all my moulds were polyester, and my experience is predominantly with that Resin.

I have made my patterns for cutting the glass. Now I find I only have woven rovings or cloth, which although draping well, do not pick up detail like surface tissue did.

So many niggly issues. In the past I was just a member of a small amateur team, with a guy from Piranha mouldings, a member of the Manchester Canoe Club (as I was) and a Scout Master, whose hut we used (making some canoes for the scouts). I had my Trylon book, plus all the pamphlets from Strand Glass and their technical support. Now I know nothing.

Yet, big moulding jobs like yours need a lot of preparation and so on.

For me the wrong time of year for my moulding as I must do it in the garage and it is probably border line on temperature, and the atmosphere far to damp.crying

I will keep watching with interest.

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