Chris's Bella Ballerina HD

[Rosco]

.....and Merry Xmas to you to Chris, from the hottest capital city in the world on Xmas day at 41.3C - Adelaide, South Australia.

Rosco

[Peter Miller]

Posted by Rosco on 25/12/2016 08:27:17:
.....and Merry Xmas to you to Chris, from the hottest capital city in the world on Xmas day at 41.3C - Adelaide, South Australia.

Rosco

Sounds like Christmas in Aden!!

[Peter Miller]

And a Merry Christmas to you Chris.

[McG 6969]

Thank you all for your kind wishes, gentlemen.

The LotH liberated me from some social duties for the afternoon, so I will be able to spend a few hours at La Grotte. I’m looking forward to cut that second wing tip and to try to match it with the earlier specimen.

Mustn't forgot my coat though as it seems to be a 'bit' colder here...

Hakuna matata

Chris

BRU - BE / CTR Twins Control

[McG 6969]

Hello again everybody,

When I used to prepare the second tip, I really checked twice that it really was the mirror view of his brother. Unfortunately it was also glued still using Por… but we know that problem already now.

I just had to unscrew the bits, to turn the base plate upside down and to screw the pieces back on.

In my ‘electro-scrap-drawer’, I found a spare wall charger with the same 3,5mm plug but giving 6,5V and 2000mA and decided to use that one for the Nichrome cutter.

I’m not sure if it was easier by being my second attempt or if the slightly higher voltage/current helped as well, but it felt like this tip was ‘smoother’ to cut than the first one.

This time I also thought about shooting a picture before starting to sand…

The Por seems to have been partially ‘burnt’ out by the wire… so, a bit less to cut out this time.

Hakuna matata

Chris

BRU - BE / CTR Voltage/Current Control

[McG 6969]

Hello to all,

Busy times in La Grotte these days but anyway there is really no chance of planning any skiing activities right now here in BE.

Back to the foamy wall-sander and I had some progress with the two wing tips.

The Por problem has been ‘cut’ away and the small slots will be filled with OneTime filler later on.

I also made a few holes in the thickest part of the tips with a hole saw and ‘Dremeled’ out the interior to win a bit of weight.

A dry fit of both tips is going to allow me to remove as much as possible foam before gluing them on.

It seems now that I have been generous enough with the measurements but I guess it remains simpler to remove some material instead of having to add some…

Hakuna matata

Chris

BRU - BE / CTR Blue Foam Control

[Peter Miller]

The old adage

You can always cut a bit off. You can't cut a bit on.

[McG 6969]

You are a genuine adages encyclopedia, Peter.

Probably found in the same chapter as "What isn't there, weights nothing"...

Hakuna matata

Chris

BRU - BE / CTR Adages Control

[Peter Miller]

When you have been modelling as long as I have you hear most of them

[McG 6969]

I’m pretty convinced you must know them all by now with your career, Peter.

In fact, I like adages as well, but mostly trying to keep them simple so I can understand them as well…

Easy stuff like > “It’s cheaper to be rich”.

Or in the same category > “It’s better to be rich and healthy than poor and sick”…

(both of them translated French ‘silly’ stuff… )

Hakuna matata

Chris

BRU - BE / CTR Adages #2 Control

[Vince Keld 1]

Hallo Chris .I've been reading this blog with interest since the start I build like you do in fits and starts and spend lots of time in the shed looking and thinking and planning I'm also keen on trying for me new methods materials and techniques I wanted to try using lost foam moulding for my latest build bit couldn't find a suitable foam locally so tried making a block of gap filler but couldn't find anything that would dissolve it so finished up planking with balsa came out ok. I'll cut the block up to make a build frame or jig or something and probably find that acrylic paint dissolves it and sticks it to my plane. My kind of luck if it rained women Id catch my mother in law. Any way just wondering if building from depron and composites as you are and then covering with glass and resin would be any stronger or lighter than traditional methods I appreciate very well it will toughen the surface and make it more resistant to hangar rash etc I like using 6mm square cf tube from hk as wing spars and thin sheet aluminium for motor mounts and local reinforcing basically using what I can get that I think is fit for purpose. Have to buy balsa from local hardware chain store and be very selective which oftentimes amuses other customers as local hobby shop doesn't sell balsa next nearest hobby shop is 600 kilometres away. brave of you to post a blog and carry on enjoying this hobby in your own way.the way I think is this is my hobby Ill enjoy it in my own way and put as much in as I can and get as much out as I can and If I can Help others along the way all good If others can help me all good. you have some very interesting ideas some of which Ill try myself sorry for the long post and hope I haven't hijacked your thread looking forward to seeing your ballerina finished excellent work so far hope it flies as well as it will look and not if like my efforts my planes ability to fly is better than my ability to fly it cheers Vince

[Vince Keld 1]

By the way like the Idea for the wingtips

[Andrew Dunn 1]

Vince if i remember correctly acetone (nail varnish remover) will dissolve gap fill foam

and

hello chris have been reading this build from day one and as a non-builder/flyer i find it very interesting to the point i'm actually starting to think about maybe giving this building lark a try myself

[Vince Keld 1]

Andrew.tried acetone will clean it off your hands etc. before its dried but only sort of softens the surface slightly until it evaporates when set tried various industrial solvents with similar results including spray gun cleaner which dissolves all types of dried paint from nozzles etc.need to find insulation foam or similar. But live in western Australia and fibreglass insulation is most commonly used here don't want order a small trial block online as probably not worth the cost for an experiment. Don't find bits in builders skips as it is not used here planking with balsa works well just wanted to try something different to see if its easier or cheaper stronger or lighter.I don't have a huge modelling budget so things need to be easy to get hold of and cheap.

Chris here's an adage concerning tools I'e you can never have enough its better to be looking at it than be looking for it cheers Vince

[Vince Keld 1]

Was looking for the sort of foam Chris used for his wingtips which is why I posted on here, was thinking that with his experience in composites he might know of an alternative. Will keep looking but for the moment its not a show stopper. Going to site for a few days tomorrow will start a build blog when I get back but am part way into the build of an own design electric glider so cant start from the beginning. Sorry for hijacking your thread Chris cheers Vince

[McG 6969]

Thank you for visiting and for your comments, gentlemen.

And no apologies needed, Vince. You're absolutely not "hijacking" the blog.

If you're into 'lost foam glassing', let me admit that I never really had some experience with it. I always made composite parts that needed several final items, so always worked with female molds like I did for the Bella's cowl.

Regarding dissolving the foam, I should have give the same answer as Andrew, being acetone. I don't know what kind of 'filler foam' you are using of course, but you could try cellulose thinner as well. Some types of foam can even be dissolved with simple automotive petrol.

Concerning paint on foam, if you use a water based acrylic paint or varnish, you won't arm anything.

The blue foam I use for my wing tips comes from an artist/craft shop, used by architects to create building models as you can give it any shape you want. In Europe it is used for insulation as well, sometimes coloured pink or green. If you can't find any, try to locate a builder of RVs. They use dense foam for insulation of the walls of caravans or motorhomes.

If that doesn't help, you could always laminate some Depron sheets together with foam safe glue. Try to avoid UHU Por at he edges though as it sands horribly. I just experienced it by laminating my wing tips.

Maybe using Gorilla Glue and keeping some pressure to the bits while drying. You can even apply a coat of varnish to the sanded item to close the pores before you start glassing.

Since you asked about the Depron plus composites, I'm just experimenting. The problem with Depron is that even when you're just 'looking' at it, it gets 'hangar rash' already. Hence the glass + acrylic varnish to make it somewhat ding free. If you use polyester or finishing resin the result is stronger but a lot heavier. After some testing, I'm now using a very hard drying 'marine' acrylic varnish and it works really great.

I have still to test it but applying some Freddie B Sauce to the glassing as I explained earlier in my thread, could even give it a nice 'scalish look' finish without any major weight penalty.

@ Andrew > If you're still a non builder/flyer, don't worry, but just give it a try. Even with a very cheap balsa kit - I bought an Idol kit from HK at €16,- during a Cybersale - or a Flite Test foamie. Just do it. You know yo want it...

Hakuna matata

Chris

BRU - BE / CTR Acrylic Control

[McG 6969]

Hello to everyone,

I finally managed ‘once again’ to have a bit of ‘very’ slow progression.

The TE of the port wing has been sanded to shape together with the tip rib and the LE was glued on at the entire span.

The wing is now ready to accept both tips but first those had to receive some filler for the ‘Por cut outs’ and be further ‘profile’ sanded.

When the first one was done, I remembered my responsibilities towards our Weight Manager and had a go for the scale. As it is 18gr now, I could estimate that, with the foam that still has to be sanded down at the back and at the rib side, the final weight will be around 12>13gr.

Possibly my sanding skills are reaching a kind of supernatural level or - more realistically - it must have been my 'Lucky Day' without any doubt, but the second tip came out at precisely… 18gr as well.

I think I could easily get used to have some more of those ‘Lucky Days’…

Hakuna matata

Chris

BRU - BE / CTR Reality Control

[McG 6969]

Hi everyone,

It’s about time now to definitely glue the wing tips into position.

Nothing much to tell about this, except maybe that I used Pattex Styropor instead of UHU Por. As you can imagine, I had some testing done beforehand and the Pattex works very nicely and is thankfully a lot less rubbery than the Por if some sanding is needed. I have no idea of the chemical composition, but another difference is the white colour instead of transparent and the fact that it cures faster as well.

I tried several times to obtain a better picture showing the ‘dihedral’ of the tip at the TE, but I’m afraid this is the best angle I could get so far.

Well, it’s obvious now that there will not be any ‘bench flying’ in Christmas spirit or Season’s sparks and firework, but that’s unfortunately the way it is. Still on track though with the Bella for Greenacres… 2018.

I do have a slight feeling that the blog’s visitors don’t really like my wing tips as since the beginning of showing pictures of them, the comments remain very few… but then maybe everybody started building their MB Skywriters already.

Hakuna matata

Chris

BRU - BE / CTR Pattex Control

[Peter Miller]

Just because we don't go into raptures over the tips doesn't mean we don't like them.

They are nice wing tips and custimze the wing the way you like it.

Normally as far as I am concerned the tips are merely there to stop the wing fraying at the end.

[Mark Elen]

Hi Chris,

Those tips look great. I'm really not looking forward to the built up version of those. If mine look half as good as yours I will be very happy.

Regards

Mark

[WolstonFlyer]

Hi Chris, I am still here reading your blog when I get chance, it is looking great!

[Colin Leighfield]

Nothing wrong with those Chris, proper job. I'm all for introducing a bit of originality into these builds, apart from individuality it gives you a chance to try out different ideas.

[Simon Chaddock]

Chris

They look fine to me.

Is still a bit of sanding to do?

Will you do this before or after the tip is fixed in place?

If after will you be able to avoid marking the Depron wing surface?

Don't worry - just me playing devils advocate!

[Rosco]

I'm still here too! Work..work..and more work has kept me busy but I have been watching.

Tips look good, weight looks good, so all in all, it's looking good!!!

Keep it up my friend.

Rosco

[McG 6969]

Thank you all for your comments, gents.

@ Peter > Not so sure if I understand your “fraying” correctly, but I suppose it has something to do with the ‘battle’ between the low & high pressure layers at the tip?

@ Mark > Looking at the quality of your build so far, you won’t have too much of a problem with your wingtips. Now, I wouldn’t really dream of having a build up version of my foam ones though. On a side note, I was sóó envious regarding your Easy Touch sander that I’ve ordered one myself.

@ Wolston > Have you made some Ballerina progress lately?

@ Colin > A “bit of originality” was indeed what I was looking for with the Islander-ish tips, but then it makes my progress so much slower again.

@ Simon > You’re allowed to be ‘my’ devils advocate as often as you like as it makes me ‘pondering’ about things. So, yes there is still some final sanding to be done now that the wings tips are glued on. I’ll try to be very careful with the Depron by covering it with layers of masking tape before gently ‘talking’ to the wall sander sponge. Promised. But that will be a job for 'next year'...

By the way, have you been using the Pattex Styropor already?

@ Rosco > I’m quite happy myself with the weight of the tips, but glad to see it confirmed by the Weight Manager himself.  

Hakuna matata

Chris

BRU - BE / CTR Thank You Control

 

Edited By McG 6969 on 31/12/2016 10:51:19