Boomerang didn't come back

[Brian Dorricott 1]

You know the scenario favourite trainer flies in wind starts first touch and a joy to fly , 2 deadsticks second one a little more terminal . Boomerang now is truncated up to LE engine tank etc all off . Everything to rear of LE fine untouched and secure so instead of chucking it how would I start to repair it ? I suppose it doesn't have to be exactly as was just strong enough to take engine and tank , 2 of the formers are still intact but all the thinner ply is confetti . I have a buddy with a new ARTF Boomerang should I trace that and start from there ? I have no sides to build to and the original was ply skinned in balsa .

I thought maybe 4 longerons epoxied to existing frame then formers and finally skinned in balsa unless anyone has a better idea !

If you make the front too heavy would that shift the cog to far forward ? Does the cog change if change the design.

I will try and get a decent picture to show what I mean tomorrow .

If enough votes to bin it I might just do that !

[kc]

First of all read Peter Millers article on this forum - Features- Building Technique - Dont Bin it Fix it- parts 1 & 2

Then post a photo and no doubt you will get some help. Anything is repairable but it depends on the work you want to put in. Probably making a new front end is the best way, but maybe the parts can be stuck back together and reinforced, or used as a pattern.

Edited By kc on 27/12/2018 18:11:07

[John Rudd]

Its all well and good repairing a model....but do remember, any repair will add weight and may not always be any stronger than the original fuselage...

I've made new fuselage parts by copying the outline of the original and making new...Was it worth the effort? Depends if you like the plane enough....In my case, I'd say so.

[alex nicol]

Firstly, sympathies.....I think we've all experienced similar. I have a simple formula which has been reasonably successful.

1 ensure you recover every bit of wood no matter how small

2 carefully remove engine/tank throttle pushrod

3 peel covering back 2-3inches on the good bit of fuselage

5 carfully piece together the front end like a jigsaw ensuring it is straight ......use cyano

6 apply epoxy and glass cloth from 3 inches behind the break to as far forward as required (use a stiff polythene to cover this and squeegee out the excess epoxy......once dry this can be peeled off)

7 apply covering and off you go

You'll most likely find it'll be stronger than it was pre accident.

Good Luck

[Stephen Smith 14]

Don't mess with all that, just put the broken bits roughly where they came from and secure with cable ties and gaffer tape, sorted.

Edited By Stephen Smith 14 on 27/12/2018 21:18:36

[J D 8]

Bit of the Charley Drake's here [remember him?] I built an aircraft that was based on a Peter Miller plan that I made with an extra strong center section and a somewhat weaker nose section.

Many years later it is still going strong with its now third new nose section. It once flew flat out into the trunk of a large oak, such was the impact the OS15's crank came out of the backplate! The crumple zone nose did its job,the rest of the air frame had little damage and was soon airworthy again.

[Brian Dorricott 1]

Alex Nicol you have inspired me and I did collect all the big bits and I used to like jigsaws as a kid so you might be on to something there , sounds like a plan ! Think I'll clear the dining table and see what we have got , I'm a fan of using a bit of thin cyano as a stiffening agent just have to watch where it goes . Only thing I have ever glassed is a wing joiner is it the same procedure ? While that's going on better put the SC46 on the test bed and find why I got deadsticks in the first place ! Cheers all for answers glad I didn't send it to the tip now !

[David Davis]

You're luckier than I was!

[Peter Miller]

Trim the remaining sides to a Vee shape in side view. You will have to remove the former at the LE.. Cut new sides to fit.

Graft the new sides on with 1/8" plywood doublers inside the fuselage. REplace the former you removed which wil have to be thinned down to allow for the doublers.

Rebuild the front as per the orginal.

I have done this quite a few times including a club members model with a .90 in it. Flew fine afterwards.

Mind you, he did demolish the model in a big way shortly afterwards includng the wing and just about everything else.

NO, I didn't repair it again

[alex nicol]

You're welcome,

I meant to add, when doing the glass work, use slow curing epoxy and warm it up to just above room temp......it'll go very thin.....makes it easier to soak into the glass cloth. also when you squeegee it through the polythene it gets rid of excess epoxy and after it has dried when you peel off the polythene you'll get a very smooth glass like finish which will be almost invisible under the covering.

A few years back I had the misfortune to find a fence post with my Maricardo the fuselage snapped at the wing Le and Te.....I glued the three bits back together, Glassed over the repair areas and it's still flying today

[Cuban8]

Brian. Some years ago, one of our club members was going through a patch where it seemed that every third flight or so would end up with a damaged ARTF model. Every so often the damage was really serious and I always thought that the model was then only fit for the bin, given that what was left was not much more than litter.

Within a fortnight, the model would be repaired and recovered to such a standard that I had to look inside the fuz to check that he hadn't bought a new one. Everything had been stuck together jigsaw fashion, and to a very high standard - I honestly don't think I could ever have achieved the quality of the job, even if I had the patience to do it. This occurred several times and each time the model was repaired to a high standard and flew again.

It's amazing what can be repaired if you have the will to do it.

[Ian Jones]

Brian, if you accept that everyone needs a trainer and you have one of the best then you options are threefold:

1. repair
2. replace
3. use for spares

Option 3 doesn't provide you with a trainer unless you combine it with option 2.

Option 2 is going to cost you and you will still use parts you would have used in option 1.

Option 1, if it fails to fulfil it's purpose still leaves options 2 & 3 available.

It's a repair job alright!

[David Davis]

Posted by Ian Jones on 28/12/2018 12:30:38:...

...It's a repair job alright!

I've given mine to my trainee to repair!

[Mike Etheridge 1]

I will not let my planes or any I am given die !.