HPA

only fitting, right Lurk?

As Γιώργο has saved me the bother of starting this thread all I will say is that this will only be a placeholder for the thread I started over on aeromodelling.gr before Γ donned his Father Christmas disguise and built this place for us to enjoy.  As it progresses I'll bump this thread.

Active Thread Here (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.0)

Hi Lurk,

just a side note,

I cleaned up the test forum I had set up in aeromodelling.gr and moved your build thread to the free flight constructions board. Also edited the link in your previous post to the new location.

So you are free and welcome to continue wherever you prefer.

Thanks Γιώργο.

Bump! (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg343834#msg343834)

Bump! (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg343850#msg343850)

Bump! (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg343880#msg343880)

Great thread lurk, very brave with the reflex tail


Shame the thread isn't on here in some ways as this one is becoming like driving down your average british road ....full of bumps  ;D

Hi Lurk,

Other than the somewhat dublication of effort, I see no problem posting on both forums. Here in english and there in greek/english. Same pictures set...

Another pothole (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg343948#msg343948).  Just for Chris. :)

Thanks Lurk...


That's a lot of Herring.. but I am told that's where Scotland gets it's brains from ??? or at least that's what Ivor Cutler told me

In case you are wondering what an earth I'm going on about see below

Life in  a Scotch Sitting Room Vol 2 Ep6 by Ivor Cutler


Nice looking wheel construction btw

Where can I find the spoke lacing guide? Looks like a vital tool indeed!

Chris> ...that's a lot of Herring...
Havers man, it's only just enough. :)

Henk> Where can I find the spoke lacing guide?
The lacing pattern is the same as the one Γιώργο Κ gives in his spoked wheels PDF so, providing you've got some compasses, you can always draw it afresh for each wheel set.

I doubt you'll be shocked to know that I cheat and have an SVG file that lets me adjust the wheel diameters so I can resize and centre the "rims" for a new wheel set with the least expenditure of effort.  Joking aside it does mean if you make a mess of a lacing guide - no, I'm not going to tell you of all my mistakes, allow a chap some dignity :) - it's just a matter of reprinting it.

If you'd like a copy let me know your e-mail address (hit the envelope icon under my avatar) and I'll send you one.  Anything that understands and edits SVGs will do.  I use Inkscape.

Hi Henk,

Are you refering to the guide or the template?

The guide is here

https://hpa.aeromodelling.gr/index.php?topic=112.0

I cannot help on the herrings though, you are better located for that...

George

Hey George,
Many thanks for the tutorial. Now I have to find an airplane with spoked wheels to model! If I do, I will be sure to use a two pound can of Greek olives for a weight!

Oh dear, oh dear, oh dear.  Who's a chump then? (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg343978#msg343978)

Phew! (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg343981#msg343981)

Phew indeed , nice job  ;D

It marches very slowly. (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg344000#msg344000)

Would you believe four evenings work?  (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg344048#msg344048)

A bit further forward with the dash and top cowling. (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg344069#msg344069)

Top cowling louvres in place. (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg344072#msg344072)

Nose plug shaped. (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg344099#msg344099)

For such a small part there was rather a lot of work. 

Next bits. (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg344202#msg344202)

Brush painting with aluminium paint is harder work than it should be and I may revisit bits of the motor panelling.

It looks pretty good to me Lurk.

I was amazed at your use of the approximation for the curved sheet on top of the engine cowl!

happy building.
John

Quote from: OZPAF...amazed at your use of the approximation...

Ummmm.  Why?  It's poor engineering/carpentry/dress-making practice and even poorer economics to waste material unnecessarily and wood doesn't grow on trees you know.  Well, it does, but err, umm ... Oh! You know what I mean!

Well I was impressed - I'll admit my ignorance - I had never heard of this approximation.

Happy building.

John

Quote from: OZPAF on Mar 24, 2026, 01:24 AM...I had never heard of this approximation.

No, nor had I until I went looking for a simple way to approximate the path length/circumference of an ellipse fairly closely and a bit of digging turned that up.  Handy innit?


Keep chipping away... (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg344217#msg344217)

Inchworm, inchworm.  Measuring the marigolds... (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg344283#msg344283)

Not stalled at all.  Oh dearie me no.  Merely... taking a breather. (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg344457#msg344457) :)

Covering underway. (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg344459#msg344459)

Great to see progress on the Chiribiri. The wings look beautifully light

Hi Lurk - have really enjoyed your build so far.

With your side-by-side English, Greek, and Aeromodelling Hieroglyphs you have created a Rosetta Stone from which hopefully anyone possessing at least one of these languages can see how you have built this model!

Couple of quick questions - sorry if these have already been answered:

1. what did you use for the u/c skids - noting one has cracked in storage - is it bamboo?

2. what tissue are you using? Esaki 'white'? Or did you find something with a more vintage colour?

Re the spoked wheels - I have a few Hungerford wheels from 'back in the day' and every time I want to use them they seem a bit chunky also. Esp for the pre-WWI types which seem so skinny. I don't plan to sand mine thinner tho! Just have to find the right aeroplane...  :)

Tim

Evening Tim,

THB> With your side-by-side English, Greek, and Aeromodelling Hieroglyphs you have created a Rosetta Stone...

Umm. Err. As Γίωργο will confirm the Greek is very... approximate and any putative Champollion would have his or her work cut out trying to use it. :)


THB> ...what did you use for the u/c skids - noting one has cracked in storage - is it bamboo?

Basswood.  I used bamboo for the Mooney peanut version (as recommended) and adhesion between the various framework components was poor.  If this one is anything like the Mooney one I built then I expect I'll have to build at least one more complete undercarriage framework before it's even half way through trimming.  There's a word for people who build Chiribiris, on the tip of my tongue, begins with "m" ummm, errr madmen?  Nooo. Morons?  Hmm no. Ahhh... I have it;  masochists.

THB> ...what tissue ... did you find something with a more vintage colour?

A tale in itself.  I'd run out of the period correct "antique" a lovely mucky white colour (like the one SAMS used to supply) that Bill Dennis gave me a year or two back and I was moaning about it somewhere and John Whatmore (another Trinity inmate parishioner) very kindly let me have a couple of sheets of someone else's antique.  This is more a very pale tan than mucky white, but CDL does darken over time when exposed to sunlight so I'm more than happy with it.

Thanks!

Quote from: TheLurker on Jun 01, 2026, 10:50 PMTHB> ...what did you use for the u/c skids - noting one has cracked in storage - is it bamboo?

Basswood.  I used bamboo for the Mooney peanut version (as recommended) and adhesion between the various framework components was poor.  If this one is anything like the Mooney one I built then I expect I'll have to build at least one more complete undercarriage framework before it's even half way through trimming.  There's a word for people who build Chiribiris, on the tip of my tongue, begins with "m" ummm, errr madmen?  Nooo. Morons?  Hmm no. Ahhh... I have it;  masochists.

Hi Lurk

I have never had a problem with bamboo joints coming apart.  I use aliphatic glue for bamboo to wood joints and 30 min epoxy for bamboo to metal joints and both seem to work fine . 

Then again, I don't suppose that my joints are ever end grain to long grain like between a U/C leg and a skid or axle.  In those cases I would use a metal pin as a dowel through the joint and glue with epoxy. 

Cheers

Jeremy

Evening Jeremy,

I think a large part of the problem is that the joint surfaces are very, very small and regardless of adhesive there just isn't enough area to withstand the shock from a hard landing on a gym floor, nor is there enough wood to take a dowel, unfortunately. 

I tried various reinforcing schemes on the peanut version's 2nd UC frame, mainly wrapping with fine wire, but they were ineffective.  For this version I've gone for a mix of cyano-soaked 45gsm paper reinforcing "plates" and cyano-soaked thread bindings. The reinforcing plates have been painted gun-metal in the hope that they look like the sort of thing you'd find in real life. See the circled areas below.

I've only just latched on to this thread. Very entertaining and interesting Lurk, and thanks for the 'chord of a circle' wheeze. Kudos.

Stephen.

Quote from: Prosper on Jun 04, 2026, 03:38 PM.....'chord of a circle' wheeze.

It's nice when you turn up stuff like that isn't it?

Started doping (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg344472#msg344472)

Fin / rudder today. (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg344477#msg344477)

Split over two posts.

Silly question.

Once you apply the dope over the rudder surface, or water it for shrinking, won't the pencil marks be affected?

Because I loved the idea!!

Not a silly question at all.  Briefly; pre-shrink tissue, apply lettering & dope opposite side to lettering.

Flat components rarely need any further shrinking if you apply the part to the tissue while it is still in the frame and under tension.   

Sometimes, rarely, a component will need the very gentlest of steam shrinking before doping, but crayon/pencil is usually safe under steam provided you don't go crazy.  This one wasn't shrunk any further.

Pencil (& cheap crayons) seem to be dope-fast, but even if they're a bit soluble you're doping the opposite side to the lettering so there's no drag from the brush to disturb it. 

The final snap shows the doped fin. 

All clear!!

Thank you.

Definitely will try it!

Beautifully masochistic Lurk. :)  The neatness of your builds always inspires me.

John

Fuselage lettering started. (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg344488#msg344488)

Fuselage lettering done. (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg344496#msg344496)

The end is in sight... (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg344501#msg344501)

Going to be busy for the next few days so, perhaps done by middle of next week.

Very impressive - like your neat covering.

John

Quote from: OZPAF on Jun 16, 2026, 10:25 AMVery impressive - like your neat covering.

Thanks John, but the camera isn't as good as the MK I eyeball at picking up the wrinkles of which there are an multitude. :)

Rollout (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg344520#msg344520)

Wonderful!

I wouldn't go quite that far, but thank you. :)

Beautiful model!!
Love how you made the letterings, great outcome!

Cheers, Ramses

Brief notes on test flights. (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg344834#msg344834) Don't get excited.

The traditional sticky end. (https://www.aeromodelling.gr/ForumS/index.php?topic=59825.msg344836#msg344836)  No bad joke left unused. :)

Some bits will be salvaged, the wheels especially, and a wing will be kept as a reminder to me not to be so silly as to attempt another Chiribiri No. 5.

It's a shame, if you can get it past the trimming stage in one piece the design will fly and fly well.  But... it requires so much nose weight, some 2/3 of the built weight for mine, that any landing on an unforgiving surface is almost certain to end in bits of airframe being scattered to the four winds. 

Electric RC may be the way to go.

Sorry to read that, Lurk.

Oft I've carried the sorry remains of a model indoors, wondering what to salvage - and end up repairing/rebuilding the model. Is yours really a hopeless case?

Stephen.

Thanks for the sympathy, but it's FF aeromodelling.  Such things go with the territory.  Anyway gravity always wins in the end and I did get a few half way decent flights out of it so I'm reasonably content.

Hopeless case?  No, no at all. It's the ratio of workshop time to flying time that clinches it. What with work and domestic duties I can't afford to spend most of a day fixing a model - which is how long yesterday's patching up and re-rigging took, for the sake of 5 minutes flying time.  I'd never get anything new built or any of my other models patched up.

I do like the design and one reason for making the larger version was to see if it was possible to make one that wasn't as fragile as my Mooney Peanut version so that I could spend more time flying it than repairing it.

Definitely sad news for your lurk.

It's a pity that it wasn't a pusher canard design - you would have had a fighting chance.

John

That is a real shame Lurk.

It sounds like it did show promise at least even if briefly so can ultimately go in the Lurker Aviation hall of victories.

Quotea wing will be kept as a reminder to me not to be so silly as to attempt another Chiribiri No. 5.

Never say never ;) electric power could get it out of the rubber power doom loop of more power = more weight = more power.... and well you still have the wing

Yes, a real shame, but also somewhat of a success too, so please accept my heartfelt com/n/miser/ratul/ations!


(Also, if it's any consolation, I now kind of want to do a Chiribiri myself.)

I have a wonderful book called French aircraft before WWI by Opdyke. Not sure but think that pretty much half of the aircraft featured never achieved flight... and most of those that did ended up as matchwood soon after. So your flying model of a pre-WWI aircraft is surely batting above its average! Not to mention we get the benefit of members stand front row seats to watch the action  ;D
Tim

Thanks for the sympathy and commiserations chaps, it's appreciated but not necessary.  I went into this project knowing it might not survive trimming.

Quote from: Squirrelnet on Aug 12, 2026, 09:51 AM...get it out of the rubber power doom loop of more power = more weight = more power.... and well you still have the wing

Power isn't the issue. It's fragility.  I was getting 13-15" from 800-900 turns of the motor and the 80% limit for the motor is 1300 which, all being well, I'd hope would give somewhere around 25-30".

Quote from: Pete Fardell on Aug 12, 2026, 11:27 AMAlso, if it's any consolation, I now kind of want to do a Chiribiri myself.

If you're serious about that I'll update my plan and you can have copy.  I had intended to alter the wing root mounting points to deal with the issue that terminated this one.  As for the undercarriage, I can't see a good way of making that more robust without sacrificing scale dimensions or weighing it down with shedloads of wire, but...

... what you can do is trim it without the undercarriage (as I was doing) and only fit it when all's well.  You can get away without the underwing rigging for this, but it might be better to run some temporary rigging tacked to the fuselage.

Quote from: THB on Aug 12, 2026, 11:54 AMNot to mention we get the benefit of members stand front row seats to watch the action  ;D
Tim

We aim to amuse. :)