Sidewayskiwi
1531014860879-442648762.jpg  1531014972086-1068174068.jpg 
Wasn't even a hard landing
With all the repairs was really too heavy to fly
Going to try E3Scotts idea on DTF and paperless DTF
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quorneng
Un-reinforced foam?
This scale Fairey Delta 2 EDF is Depron and only Depron with absolutely no reinforcing anywhere.
AcrylicBlue.JPG 
Certainly not in the 'indestructible' class and has to be belly landed with care but it flies very nicely.
It has even gone through major repairs like this
Crash.JPG 
Without reinforcing note how the structure 'crumples' to absorb the 'lawn dart' impact leaving the rest of the structure (and the electrics) completely undamaged.
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Lgel
Quote:
Un-reinforced foam?
This scale Fairey Delta 2 EDF is Depron and only Depron with absolutely no reinforcing anywhere.
[ATTACH=full]55571[/ATTACH]
Certainly not in the 'indestructible' class and has to be belly landed with care but it flies very nicely.
It has even gone through major repairs like this
[ATTACH=full]55572[/ATTACH]
Without reinforcing note how the structure 'crumples' to absorb the 'lawn dart' impact leaving the rest of the structure (and the electrics) completely undamaged.

Superb repairing skills!

Cheers.
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Lgel
Quote:
[ATTACH=full]55490[/ATTACH] [ATTACH=full]55491[/ATTACH]
Wasn't even a hard landing
With all the repairs was really too heavy to fly
Going to try E3Scotts idea on DTF and paperless DTF

Airframe must be strong enough (just enough) to cope with flight stresses.

No amount of reinforcing will ever save a plane from a crash, but an heavy plane will be much more likely to crash.

Cheers.
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Sidewayskiwi
Quote:
Airframe must be strong enough (just enough) to cope with flight stresses.

No amount of reinforcing will ever save a plane from a crash, but an heavy plane will be much more likely to crash.

Cheers.

The other part of my post was hobbyking foam
In no way can that hold an airframe our wing with no reinforcements
But hobbyking foam is the cheapest most easily available foam in NZ
I can get depron but it is 10 times the price per sheet of hobbyking model foam
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quorneng
HK foam cannot support a wing without reinforcement?
Just as an experiment I built a 40" wing (2 x 20" panels) from 5 mm underlay foam (green but the same as HK foam)
UndlyWing1.jpg 
No structural reinforcement apart from tiny balsa leading and trailing edges to give a bit of 'ding' resistance.
The completed wing supporting 18 oz (510 g) when supported just by its tips.
18oztest.jpg  Yes it bends a bit but loaded like this creates a stress at the centre equivalent to a uniformly distributed load of at least twice this weight.
The completed wing on my 'hack' pod and boom pusher fuselage which uses a 150W out runner and a 1500 mAh 3s LiPo.
UnderlayWD.JPG 
I am sure I could break it if I try hard but it is fully aerobatic and has not failed so far!
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Sidewayskiwi
Quote:
HK foam cannot support a wing without reinforcement?
Just as an experiment I built a 40" wing (2 x 20" panels) from 5 mm underlay foam (green but the same as HK foam)
[ATTACH=full]55594[/ATTACH]
No structural reinforcement apart from tiny balsa leading and trailing edges to give a bit of 'ding' resistance.
The completed wing supporting 18 oz (510 g) when supported just by its tips.
[ATTACH=full]55595[/ATTACH] Yes it bends a bit but loaded like this creates a stress at the centre equivalent to a uniformly distributed load of at least twice this weight.
The completed wing on my 'hack' pod and boom pusher fuselage which uses a 150W out runner and a 1500 mAh 3s LiPo.
[ATTACH=full]55596[/ATTACH]
I am sure I could break it if I try hard but it is fully aerobatic and has not failed so far!

I fly parkjets
So the only built up wing I can make is a KF2-4
I found iam really limited to 28-30 max wingspan for these wing platforms
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bogusbandit56
Quote:
I fly parkjets
So the only built up wing I can make is a KF2-4
I found iam really limited to 28-30 max wingspan for these wing platforms

I can confirm that hobbyking foam is not as strong as the green XPS that is available from from ebay in the UK.
The green XPS is more rubbery and resilient than the brittle hobbyking stuff.
I built my Sopwith 11/2 Strutter fuselage and empenage with green XPS wrapped with BP the wing is hot wired from salmon coloured insulation foam.
Wot, no Depron?
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Sidewayskiwi
Well the experiment was a success
Hobbyking foam rigid and resilient
However
Minwax and Brown Paper turned an 8 gram vertical tail piece into a 20 gram finished item
So weight is again the issue
Using water base minwax on bare hobbyking foam and will check the results once cured
Preliminaries look encouraging
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Lgel
Quote:
Well the experiment was a success
Hobbyking foam rigid and resilient
However
Minwax and Brown Paper turned an 8 gram vertical tail piece into a 20 gram finished item
So weight is again the issue
Using water base minwax on bare hobbyking foam and will check the results once cured
Preliminaries look encouraging

If weight is a concern, instead of brown paper (they are many weights of brown paper available) use regular newspaper (a rare material nowadays), I have used it with success as many glider builders.

Be sure to remove the excess of Minwax.

You don't have to cover the whole surface, I covered upper and lower leading edge of wings.

Have a look at my build log of Bob's Ho229.

Cheers.
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trying2fly
Quote:
Un-reinforced foam?
This scale Fairey Delta 2 EDF is Depron and only Depron with absolutely no reinforcing anywhere.
[ATTACH=full]55571[/ATTACH]
Certainly not in the 'indestructible' class and has to be belly landed with care but it flies very nicely.
It has even gone through major repairs like this
[ATTACH=full]55572[/ATTACH]
Without reinforcing note how the structure 'crumples' to absorb the 'lawn dart' impact leaving the rest of the structure (and the electrics) completely undamaged.

Looks better than many of my finished planes!!!! chas
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bogusbandit56
Bimo started a thread about three years ago, you may find some useful hints and tricks from the many contributors.
https://rcpowers.com/community/threads/repairs-and-enhancements-corner.18643/?_params=Array
Wot, no Depron?
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