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S1581 Hawker Nimrod MkI

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Okay it seems I un-beknowing deviated from the plan. mind you I wouldn't follow the plan in this instance as it would mean a ply plate up against the outer covering.

Those steeley eyed amongst you, especially you Mr Sephton, one house point btw May have noticed that the ply plate is clearly shown as being on the underside of the tailplane, recessed into the rib.

Well the rib is not solid as you know and has a slot. therefore when you thin it further to allow for the plate you are creating a weak point right where you are trying to create a strong point.... not smart in my book. I have used the gap between the upper and lower ribs to my advantage and slid the 1/16th ply plate in there. I do have to pack up the mounting point to make sure the bracket sits on the surface, but I think this is much neater. Also on some of our subjects we have more struts and wires than on the plan. so win win I reckon?

okay enough of the tailplane. I joined the two fus halves the same as others have done and turned my attention to the bulkheads.


F1 caught my eye, it was eagerly awaiting its turn to become part of my Nimrod. However i was about to break its heart. For though it looked at me mournfully with those three holes and two fus slots I had to deny it a chance to be part of the project..... I broke the news to it gently and I selected some medium 1/4 balsa and made a new F1.


F1 doesn't carry any real loads on the electric version, F2 and F4 do the donkey work.

the net result was the old F1 weighed in at a hefty 66g the new one just 11g. I am fitting a half pound sound system so it will be a useful weight saving.

Okay onwards and upwards!

Edited By Danny Fenton on 12/10/2018 19:02:05

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Made up the fuselage sides, pretty straightforward as others have shown. I don't tend to build one over the other however, I build one, remove from plan and then build the other. I think this gives the second side a better chance of being perfectly flat, but each to there own, ther is no right or wrong just what you favour.


Then I needed to look at the bellcrank position. Obviously not something you lot need to think about wink 2

bellcrank doodles 1.jpg

Not very clear I am afraid, but the forward hole in the bellcrank should be on or around the c of g in my experience. Ideally also on the thrust line, or slightly below. These positions determine the amount of pull on the lines. The leadout angle also plays into this. The bellacrank is mounted on the square section birch used to retain the upper wing, with an additiona 4mm ply cross brace between 1/16th ply doublers lining the fus sides.

The servos will be mounted high up between F1 and F2, with a detacheable ball joint link/rod from the elevator servo to the bellcrank for R/C flight.

Underneath should give room for the speaker for the sound system, though I may leave the final position until later as it will have a dramatic affect on the c of g.



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Not very much time in the workshop this evening

I have been pondering the cockpit issue, ie how do we do something scale-ish accounting for the narrow sheet sides. I think we are just going to have to settle for a floor and a half height pilot figure.


I have spent much of my time planning and measuring. The bellcrank position is worked out, and the parts loosely fitted to help figure out servo positions. The elevator servo will feed the bellcrank with a snap link so that I can change from R/C to C/L.


Fitted the motor and lightweight F1 bulkheads with some trainagle stock, also added triangle stock to F2 and F4 as they handle much of the work, both undercarriage and upper wing loading are fed through these two.


Hopefully more progress tomorrow



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Hi Martin, and thanks. Yes there is enough room. The motor mount screws are an issue and well spotted. I will see if I can stick a pad inside, just thicker than the screw heads to protect the cells. The triangle strip doesn't intrude enough to matter. Though make sure your selected packs will fit!



I will probably cut the motor shaft stub off so that doesn't intrude either. Don't know why manufacturers still provide shafts so that the motor can be front monunted with a collet, not sure anybody does that these days.....

I have received my hex bolts and have mounted the bellcrank in its final position and glued the ply brace between the doublers. I can now plan the elevator servo position.



Edited By Danny Fenton on 18/10/2018 16:32:16

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I wanted to make sure that the tailplane seat angle was as per plan. The other builders have obviously figured this out but for those yet to do this part, I made temporary "gauge" traced from the plan to make sure it is accurate.



Anyway may get some more done tonight, need to catch up with everybody else!



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Thanks Tony, one has to make an effort

As has already been mentioned it is best to use a piece of scrap to set up the position of the diagonal side formers.


A permagrit slotting tool makes light work of setting the stringer slot angle.


As I think both Andy and Tony have stated, there is something strange going on with the side sections. FS2 is so far out it may be from a different model!

It is actually worse than Andy and Tony may realise. I have a glass cowl and when you present that to the front, they are ALL to wide!!!

I think F4 is too narrow and that is why the upper bulkheads seem too wide. certainly too late for me to put right on mine, and as most of you seem to be ahead of me, too late for yours too.

All we can do is shape them in situ. Deja Vu Chippy builders?

On that note I am off to bed, it will look better in the morning, it always does.........


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Adding the cross grain sections is fairly straightforward. You don't really need to bother tracing the shape from the plan, just cut sections wider than you need. Having done one side adding the side formers first then the cross grain, I think it will be easier to add the cross grain first so have done this on the starboard side. This gives us a clear upper edge to mount the side formers against.


I found the 1/4" Permagrit slotting bar sits nicely across the fus to give us a flush and perfectly angled section. Don't worry about the shape just yet that is defined by the side formers. I will show you how they are shaped later.


Lets see if the bulkheads on the starboard side go any easier.....



Edited By Danny Fenton on 19/10/2018 17:52:49

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Used the adjacent stringers to allign FS5.


Once the formers are in position I used the permagrit slotting tool to sand slots in the cross grain sheeting to indicate the depth of the former



Then allowing a little sanding leeway saw through the balsa, linking the slots.



I am a little surprised there isn't another former under F6 on the starboard side, seems a long gap for the sheeting. I might add one.


On the iso drawings at the top of the plan the wide top stringer is shown as only going back as far as F7 then another narrower stringer goes from F7 rearwards.



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It was pointed out to me that I had omitted the upper and lower diagonals so have added them, I have seen a couple of interpretations of their fitment, so I thought I would show mine.


The triangular tang is nothced slightly with a Permagrit slotting tool. I didn't want to run the brace over the tang, and i also didn't want to cut into it too harshly, those tangs take much of the tailskid loads!

Same method was used for the upper diagonal brace.



Edited By Danny Fenton on 22/10/2018 11:35:15

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