Pics of the Chaser from IHC. All part of the archeological findings while clearing the Aeromodelling cupboard.

Catapult launch free flight glider with folding wing mechanism.  Wing unfolds at top of the height when air pressure reduces.

Quote from: Dreamliner on August 02, 2018, 08:02:38 PM
Catapult launch free flight glider with folding wing mechanism.  Wing unfolds at top of the height when air pressure reduces.

Which brand is it??.
The wing dihedral seems a lot.

Zoomed the pic and saw the Guillows logo.

@dreamliner,
What's this?
Never seen it before!

Yes, it is a Guillows kit.  Picture taken in folded wing state.  When the wing unfolds, dihedral is approx 5 degrees.

What is it called?? Can look it up in their catalogue.

It is called 54 just the digits "54" as printed on the wing,

@dreamliner
Good to see you active.
Those plastic models would make nice prizes for youngsters...

One more Bobni plan dug out from a long forgotten box. This one was in a pouch.
I have dated this as 06/2009 based on the mfg date on the quick-fix packet that came with it.(Getting good at carbon dating!!)
Interestingly this plan shows added wing tips. No balsa for them, perhaps need to use card paper.
So IHC has been doing some modifications to the original plan as time went by -- tapered wings, rounded wing tips etc.

Wonder why they did not have aerofoil ribs. Would have improved performance significantly I feel. Plan to do that keeping the other dimensions the same. Ofcourse TAN rubber will make a big difference.

I guess as a beginners model it is better to keep things simple while providing decent performance.

Just some duffer who drew this plan.
Forgot tip rib! 

Recd a query from Dreamliner re pros/cons of Monokote vs tissue, especially for small rubber power models of 15" span or less.
Responding here as it may interest a few others too.

The main advantages of Monokote are that it is easy to get a good finish, it is fuel proof, can be cleaned with soap and warm water, is puncture resistant, and lasts for decades.

But it requires the basic structure to be quite strong, like a typical RC wing with sheeted LE, TE, tips and center section. Usually found only in models of say 40" or more span.

Rubber power models usually have only about 10% structure (balsa strips) and 90% open area.
Such structures will buckle when the Monokote is tightened.

As an experiment, you can build, say, two Bobni wings. Cover one with Monokote, the other with tissue. You'll be able to see that tissue is preferable for small, light, open structures...

What is the weight difference between the two.
As far as indoor rubber models are concerned it's all about reducing weight. So material that will add to weight may not be suitable. May be okay for fun flying and where you want a durable model that can take some knocks. For competition weight is critical.

QuoteOne more Bobni plan dug out from a long forgotten box. This one was in a pouch.
I have dated this as 06/2009 based on the mfg date on the quick-fix packet that came with it.(Getting good at carbon dating!!)
Interestingly this plan shows added wing tips. No balsa for them, perhaps need to use card paper.
So IHC has been doing some modifications to the original plan as time went by -- tapered wings, rounded wing tips etc 

This is the one!
Nostalgic!
Can we get a scan of the plans?
Please?

Quote from: Glidiator on August 06, 2018, 03:08:05 PM
What is the weight difference between the two.
As far as indoor rubber models are concerned it's all about reducing weight. So material that will add to weight may not be suitable. May be okay for fun flying and where you want a durable model that can take some knocks. For competition weight is critical.

For small models built mainly of balsa strips (much smaller than 1/4"sq), the Monokote vs tissue issue is not about weight. It's about the shrinking power. Stick constructions will get crunched when you tighten the monokote. The experiment suggested (cover one Bobni wing in Monokote, another in tissue) should reveal this. Incidentally, Monokote will pull off from stick structures during shrinking due to lack of adequate surface for adhesion.
And, though I have no data, I guess Monokote will be 3-4 times as heavy as tissue/dope, partly due to adhesive on the entire surface.
Incidentally, for dope one can use NC Clear Lacquer (Rs 60 for 200ml), diluted with NC Thinner (Rs 50 for 500 ml).

To summarize, Monokote is not recommended for small models and weak open frame structures.

Sure Prabal.
Will scan and upload as a PDF in actual size. Will tile it so can print out on A4 printer.

Have never used monokote so my knowledge of that material is zero.

@prabal276,
A full size plan is hardly needed.
Pic posted by Glidiator is enough, once you know that the span is 13"!

Would suggest using the thinnest grocery bag plastic. Less than 10 microns (banned by many states) It is durable as well as light and can take more knocks than tissue. No need to dope also which will add weight.
But if you want to adhere to the original classic construction then will have to use tissue.

Can adhere the plastic to the balsa using 3M Spray glue or even a thin coat of gluestick

@Glidiator sir,
I have a Miss World wing (54", 0.19 power) whose Monokote (original, not clone) covering has survived for 35 years despite the balsa tips being chewed by rats.
Monokote is FANTASTIC.
Just not meant for small open frame models.

Meanwhile, no one seems to have tried document lamination sheet!
Even I haven't, but I have a sample a friend gave me.
Will try it and report.

On RCG, I found some people using this, and then also covering with tissue. Not sure of the purpose.

So, a lot of scope for experimentation!

If i may, what about using cling wrap? It sticks well to most of the surfaces and is also thin & light weight.