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Sailplanes International Axle build/rebuild

Konrad

Konrad

Very Strong User
I'm going through my Sailplanes International Axle kit that I got on the Aloft forums Classified ads. Let me state that these are dated, real dated like late 70's early 80's kits. That being said I have to say the CR Turbo St and the like are much better wingaron models.

In my classic spending good money after bad I'm looking to actually assembling this kit. The first major problem is that I'm seeing delamination of the obiche veneer. This may be a deal killer!

I'm looking to the Aloft hive mind for help on how to address this issue.

I'm thinking of using some foam safe CA to try to wick under the delamination. This is tricky as even foam safe CA can melt the polyester foam core. I'm also thinking that since the veneer is very porous that I might get adequate bonding just by working some low viscosity epoxy through the skin prior to the application of some glass cloth.

Axle delaminating.jpg
 
Is the sheeting still mostly attached or failing all over?

I saw an Axle kit back at the Sunset event and it had the same issues. In my mind the solution on that one might have been to fully remove the remaining sheeting and clean up the foam a bit and re-sheet. Looks like yours have survived a little better.

Think I would avoid the CA, but something thin and foam safe would be the best. Just not sure what that would be off the top of my head. Guess thinned epoxy would probably be best.

I was a bit surprised when I sprayed my Trix cores with Loctite 200, the nozzle was a little "spitty" and the chunks it put onto the foam would melt the cores a bit, but the normal misting was fine. I do not recall seeing this before!
 
There have been some re-formulation of many spray contact adhesives. Many now have acetone when in to old days they had some Ozone eating solvent. So what worked in the day might not work today. This is true of Randolph dopes. The new stuff will not go over the old stuff. šŸ˜”

Iā€™ve only found that little delamination and it looks to be at a veneer seam. But I have to admit Iā€™m not comfortable with saying the rest of the skin is well bonded.

As to reskinning that might be a problem as the kit did not come with the core beds.
 
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We will have a CNC foam cutter up and running in a couple of weeks, maybe we could cut new cores for you in about a month..? We will need to get up to speed with it before making any commitments.
 
Thank you. I might have to have you also cut a new modern set of cores for the Coyote. The set I got had wash in cut into them.

Through the magic of shear planes and stress the Coyoteā€™s wings now look passable. But I know they arenā€™t correct, perfect!
 
I'd go with a modern airfoil with a bit of speed for the Coyote. See if it could be woken up a bit more. Maybe a little different planform? I know - blasphemer!
 
Too funny Konrad, I have one of these too! But I have no wings for it.

Regarding the delamination, if itā€™s not too extensive, you could try injecting epoxy with a syringe and then just apply a little weight locally. This is what we did on the Coyote many years ago. It had been sheeted with double sided tape and was delaminating in one spot.
 
Thatā€™s a dirty little secret nobody talks about with slope and to some extent thermal duration ships, they never really die!!!

Unlike slimers (glow) models that will die from vibration and being oil soaked. But not gliders we just sweep them up off the cliff face and tell ourselves that the gut pile is just an advanced kit. Often they are forgotten for decades. But theyā€™re still in the attic, garage or basement wait for us to breathe life back into them.
 
Well, I decided to stay with the tried and true and used Titebond to address the delaminated skins. I chose Titebond because it can be thinned with water. And that Titebond can be thermally activated.

I was hoping that the water could carry the Titebond down to the core should there be any areas I couldn't reach with my 0.1 mm applicator. I spread the Titebond under the delamination working the skin up and down in an effort to help distribute the glue. I then wetted the top of the skin and worked Titebond through the pores of the veneer.

I came back two days later and found that the area was a solid as the rest of the wing. I had feared that with all the wet wood the veneer might have curled needing me to apply heat to iron down curled veneer. No curling so no need to heat activate the glue.

I'm using a filler that I got from Aloft. It is a great replacement for the light spackle we lost when Red Devil changed their formulation. This Hobby Squadron ltd. stuff sands well and looks to be the same tint as balsa. I hope Aloft can keep importing in this stuff. It is the filler we've been looking for!

IMG_8802.JPG
 
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I had one of those in 1983 or 4 - lovely little thing and maybe the best of the twisties from UK at the time, with its really thin wings.

I remember bagging the wings in 2 Oz glass and adding a fair bit of heavier glass to the fuse - which was pretty easy to get into for we amateur gynaecologists, but not so easy to get good bonding on.

In fact the fuse was a bit of an eggshell and made with Polystester resin - oh that smell - but then they all were at that time, so none lasted overlong.

I remember I got mine into a thermal at Ivinghoe and it was really hard to escape from. It didn't matter what I did, even verical dives, the model just kept on going up. I won eventially though.

The lovely Axle met its end, turning to confetti in a high speed midair with someone else's model that I remember was virtually unscathed...by that time you couldnt get them any more.

Nice memory.

Doc.
 
I didnā€™t know they were polyester. If I sand it a bit, I should be able to detect the stench to verify this even now after all these years?
 
They still stink! And not just the resin. The lay up is matted glass 4 ton weight with some glass cloth for ā€œstrengthā€ in the nose tub. There is no flat section for the wing root to seat against. Basically everywhere I look there are gross design deficiencies.
This is a classic example showing that the good old days really werenā€™t that good. Any CR turbo type ship will outperform this axel.
 
Konrad said:
They still stink! And not just the resin. The lay up is matted glass 4 ton weight with some glass cloth for ā€œstrengthā€ in the nose tub. There is no flat section for the wing root to seat against. Basically everywhere I look there are gross design deficiencies.
This is a classic example showing that the good old days really werenā€™t that good. Any CR turbo type ship will outperform this axel.
Click to expand...
"Any CR turbo type ship will outperform this axel."

I bet it wont.

Doc.
 
Ok, a poorly set up CR Turbo wonā€™t.
Iā€™ll soon find out for myself. But to be fair my Axel wonā€™t resemble the plans or kit closely. I hope add some features that incorporate some modern understanding of aerodynamics and take advantage of modern servos and radios.
 
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Konrad said:
Ok, a poorly set CR Turbo wonā€™t.
Iā€™ll soon find out for myself. But to be fair my Axel wonā€™t resemble the plans or kit closely. I hope to have add features that incorporate some modern understanding of aerodynamics and take advantage of modern servos and radios.
Click to expand...
That will be very interesting.

Doc.
 
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