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Rosco's Ballerina Build


Rosco
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Thanks Lucas smiley

Sorry, my daughter is sick so I keep having to leave the computer and its just easier for me to come back and post otherwise I will lose everything I've typed and posted if I get locked out.

once again......onwards we shall continue!

My wing profile with the relief cuts assisting to 'bend' it.......

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With the wing rib/template to show its camber. I needed to trim the ribs down a little so that the profile could be kept because the foamboard is 5mm thick so I had to lose 5mm of outside shape on the rib......

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The parts after only 3hrs of on and off work......

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Now the fun part (not). This foamboard has a paper layer on either side of the foam sheet that will not just peel off like some other foamboard paper appears too. I wet it with a spary bottle of water, let it absorb for 5 mins and then 'rub' it off with my fingers.

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Beginning the rubbing process........

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Its a little messy but not as irritating as balsa dust. I do it onto a towel so that I collect the rubbed off paper bits in the towel once there is a collection of it and just shake it out into a bin .........

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......and end up with some nice clean paperless foamboard. My rubbing method seems to take a long time but infact it is quite quick once you are on a roll. I do the parts as I come to them. I have only removed the paper from the wing so far and started to glue the ribs in place...............

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The wing is not complete in the last pic. I still need to fit another parallel 'rib/bearer' across the middle (which I have done but didn't take a pic). I then need to cut some holes for the aileron servos and then it will be almost ready for gluing up.

Then my plan is to cut it down the centre and fit a spar with the required dihedral with whatever I have laying around, possibly some balsa or even a birchwood spar. The wing is strong enough to hold itself together without a spar but the birchwood spar would allow me to mount an undercarriage to it. I'll see how I go.

So that's it at the end of play today and what kind of build thread would this be without the obligatory quick slap together of the parts for a final pic...............

 

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Until next time,

Happy building - Rosco smiley

Edited By Rosco on 15/02/2016 11:08:06

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Hi all,

I got a few hours in today and the wing is almost done.

I have added tips which I wasn't going to add at first but I think it looks better.

I have added the dihedral to the wing (1 inch at the tips I think! surprise) and all it needs is some sanding of the leading edge to make it nice and round and some very minor sanding on the tips just to clean it up a little. I will cut the ailerons out right at the last minute because I can see it being damaged whilst stored and not being worked on.

Here's some pics.............

Aileron servos in place for a guide to cut out the holes in the bottom of the wing.......(I'll need some extension leads obviously)........

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To work out where I needed to cut out the holes I stuck some pins into the bottom skin to find the corners of the 'frame' and then ligned up the servos with the TLAR approach and drew the outlines and cut them out. I'm happy to say that I got them both first time yes...........

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Servo holes cut and wing split in half. I'll just be gluing the servos to the inner wing and covering with some tape or something. I usually cut out some white paper and overlap the holes, then tape over it..............

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At the bottom of this pic you will see some foam with angles drawn on it. It is really a guide, not a spar as such but it does help to get the dihedral angle roughly into the wing halves before gluing the wing down the centre. I cut them out and glued them together, and then the 'guide' is glued into the wing......

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Top view of my 'guide'. Just to help it stay at the correct angle, I bent a BBQ skewer to shape and glued it into the 'guide/spar'. Once again, the skewer was angled with the TLAR method.........

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Front on 'guide' with the dihedral angle.......

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Wing glued up the centre and a pic to show the dihedral........

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Just a bottom view of the wing (ailerons not cut out yet).........

dsc_0034a.jpg

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Continuing on..............

My wing tips added. I thought I'd leave them off, but in the past, occasionally the odd tip scrape has been quite savage (especially with a cartwheel thrown in for good measure!) so they have some protection at least. I don't know if it makes a difference but the the pic is not upside down, the tips angle from the bottom up as opposed to the balsa build having the tips angle down from the top skin?............

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Here's the wing seat fit as per the plan. I'm happy because this means my wing has the airfoil profile that is intended on the plan.............

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And the obligatory last pic of it together again!!!..............

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That's all for today folks.

Something I'd like to mention is.........

I'm trying to keep this as close to the original plan as possible because I'm curious to know if the different build 'medium' (foamboard) will have the same flight characteristics as I'm hoping you other builders will report or even better, film, when your models are finished. The only thing that probably will make a difference is the size. Of course there are other variables but just for the fun of the build, I'd like to see.

Perhaps there should be a thread that has just pics of all the completed Ballerina models? There does appear to be a few being built.

Here's a tip that I saw somewhere and it holds true in every sense of its wisdom. I've tried to stick to it since I read it and truth be told, it's a great few words........

Build it to fly, not to crash

Until next time,

Happy building

Rosco smiley

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Oh, I forgot to mention.......Sorry about the picture quality, as I mentioned, my phones camera lens is stuffed.....AND........

Take a look at the last pic. I have made the vertical stab a different shape to the one on the plan (.....and I just posted that I'm trying to keep it as per the plan .........duh blush) anyway......

I wasn't a fan of the shape of the original one so all I did was use the horizontal stab shape to 'round' the LE shape of the vertical stab. I think it looks much better and still keeps in line with the asthetics of the model.

Once again,

Until next time,

 

Rosco yes

Edited By Rosco on 16/02/2016 11:35:41

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Posted by Peter Miller on 16/02/2016 11:53:47:

A very interesting version. I shall be interested to see hwat the finished model looks ike and to hear how she flies.

We all have our preferences for fin shape. Some manufacturers have made it a trade mark (DH)

Thanks for dropping by Mr Miller smiley

In regards to its finish, Obviously it will not look as 'clean' and 'crisp' as a balsa built, film covered model however, seeing as though the scalloped scheme is popular, I will be painting some scallops on but as for an actual colour scheme, I'm not sure about it yet.

I also am trying to keep an eye on the weight of it. If I get a chance, I'll weigh the wing tomorrow. I cant compare it to any other builds simply because it is smaller although Mr Milne's 'Baby Ballerina' may be a similar size?

The difference in the fin shape is actually very minor. Your design has it heading in a straight line to the top whereas mine just curves instead of being the straight line.

I plan on filming its first few flights so hopefully there are a few others that will do the same. Fear not, there will be some footage of it once its done smiley

Rosco

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HI Rosco.

I am sure that, like mine, it will look greatin the air. Mine always look better at a distance.

Go for the colour scheme that YOU really like. It is what I always do.

I am doing a jet style model (Super Marauder) and want to do a sort of aerobatic team colour scheme. Still haven't worked that one out yet.

I shall look forward to seeing the model in flight.

Peter

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Hi Martyn,

I was thinking about mounting the undercarriage by gluing some strips of birchply (just some stuff I have laying around) into the underside of the wing and mounting it on that.

As I say, I'm trying to keep the weight down so I'll continue on with the rest of the build and have a think about it a bit later down the track.

Hopefully tonight I'll get a start on getting the fuselage sorted.

Rosco

Edited By Rosco on 16/02/2016 20:32:33

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I like that idea M. I'll have to have a think about that one, thanks.

Tonight I got most of the main fuselage done. I still need to get the paper off and add some bits here and there but I'm quite happy with how it's coming along.

I also took some weight measurements although they are a little premature because the parts aren't completely finished however it's a bit of a guide to where it might end up.

Here's what I've got so far...

Wing - 100g
Fuselage - 67g (without tail surfaces, paper still on and unglued)

Complete airframe (wing, fuselage and tail) - 193g

That is just a rough guide, like I say, there are still a few bits that still need to be added including glue too. Then there's all the hardware and electrics.

I've got some pic's that I'll post when I can, so until then, happy building.

Rosco

Edited By Rosco on 17/02/2016 13:18:21

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G'day all,

Tonight I've got 80% of the fuze done. It's de-papered and almost all glued up.

I say almost because I haven't sorted the firewall/motor mount yet but that's pretty easy, it's just a matter of working out how far in the motor will sit.

I've got some more pic's for you all but I haven't been near my PC for a couple of days!

I should have some pic's up tomorrow sometime.

Stay tuned,

Rosco
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Hi all,

Here's the progress pics that I wasn't able to post before...........

This is just something I like to do. It is just some interlocking tabs to hold some joins together...........

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The bottom view of how the tabs interlock...........

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Lower front has the same..........

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This is what they look like once cut out..........

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And locked together...........

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The fuselage underside dry fitted prior to removing the paper and gluing.The black triangle will be the air exit hole ...........

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I was going to use the FT boys 'stiff card' method to form the turtledeck but decided to stick with my usual method and use the foamboard to form it. Foamboard will not bend as tight as the 'rounded' turtledeck requires so I just made some relief cuts and bent the upper fuse sides to help form a triangular turtledeck. I've always found that doing it like this has an advantage that you will see in another pic...............

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Here is the triangular turtledeck..........

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Continuing on.....

Just another view.......

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I haven't sorted out the front hatch yet but once I've worked out where the fireall/motor mount needs to go then I can start fitting the hatch up...............

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View from the rear all dry fitted up..........

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OK, a few quick weigh in's.

Entire airframe as is (glued wing but everything else unglued and parts still have paper on them. Also No electrics or any other hardware).............193g..........

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Just the fuselage .........67g........

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Horizontal stab...........15g.........I was curious to weigh this because I noted that on some other posts, there was some interest about the different building methods of the tail sections and the weight differences between the different styles. My model is smaller but if my maths is correct, a full size (as per the PM plan) would come in at 23g according to my calculations!................

dsc_0030b.jpg

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And continuing on again.........

 

The bottom is glued and this pic is of how I had to hold the top together to be able to glue it up. It is just a 'butt' join along the top................

dsc_0059.jpg

This pic is to show what I mentioned before about having an advantage in making my turtledeck a triangular shape. I have always found that doing it this way allows me to get a nice taper down to the tail (tail is not glued on yet, it is just sitting there for the pic)...........

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Side angle shot gives a better view of what I mean.........

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A better pic of the taper...............

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Fuselage 80% complete...........

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I also sanded the wing LE down to round it off and neatened up the tips with some sanding too. I had to put the wing in place for a pic!...........

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Last but ot least. Here is a pic to show that there is a very minimal need for any formers/bulkheads apart from a motor mount firewall..........

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Stay tuned

Rosco yes

 

Edited By Rosco on 19/02/2016 12:01:14

Edited By Rosco on 19/02/2016 12:02:30

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Hello all,

Apologies for not getting back re. some of your posts, I've just been a bit busy!

Anyway.... Back to the build.....

@js1, thanks, hopefully she'll be ok. I've built a few like this and they've all seemed pretty solid.

@PM, I've never had any problems with just a butt join however I have in the past glued a BBQ skewer down the middle and into the fuse. I will say that there comes a time when the size determines if that needs to be done or not and if I was building your 100% version, I would definitely have to do some kind of 'mechanical' attachment. I'll see how it goes without.

@MK, Thanks for your belief in the build. The proof will be in the pudding once she's commited to the air. Until then, I appreciate the comment but I'm sure there are plenty who are more worthy than me....

@CB, it could quite easily be done.

@JM, I second your motion!

Thanks guys,

Hopefully I'll have another update soon,

'til then,
Happy building

Rosco

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