ALOFT: AH-100 Build (new title)

[G-man]

This is going to save substantial building time, and eliminate some head-scratching,
the persistent, "Did I make the wing joiner receiver tube mounts strong enough?"

 

[Wayne]

Lots of visitors today, but snuck in a little redesign time. Think this is the final version, will print up another sample and make sure everything it fitting well, etc. Then maybe we can cut the wood next week.

Here is a translucent rendering to show what is going on inside.

Bay one gets balsa sheeted, so you will only see the plastic where the the bolt drops in, and the bolt will pretty much cover all of that. LOL The shear web in bay two will be slightly visible. The holes in the top are for kevlar threads the wrap around the spar cap for a little added insurance. Is it needed? No, probably not.

 

[Wayne]

FAST sample print done. Wow - Everything fits.

Now to torture test it. (This is just a high speed print in PLA, production units will be cleaner and use a much stronger material.)

 

[Wayne]

Got a little more work in on the CAD. This is what I'm doing to fight wing twist. Notice the intercostal (angled parts) are not ribs, they do not contact the film.

 

[G-man]

This project is so cool.
I just love it.
// Dave

 

[Sandman]

I totally agree, the wing joiner box alone is a unique approach.
I wanna be the first guy on my block to own one.

 

[Wayne]

Thanks guys! We have a few projects backed up, but should be able to get a prototype kit cut pretty soon and sent out to Dave for a first build.

 

[Wayne]

Still plugging away at this.. I get a bit of time here and there.

Debating adding the intercostals (diagonals) to the outer panels.Technically should not be needed. Adding them would give a consistent look, but would add to the build.

What do you guys think?

 

[Hawaii Sloper]

That is a great look. Adding them to the outer if not needed might make it look to busy or complicated. That looks clean and simple.

 

[G-man]

What do you guys think?
I say yes to the diagonals in the outer panels.
For consistent appearance, as you mention,
and it was an outer panel that fluttered on my electrified OLY-2.

 

[G-man]

"Technically should not be needed."

I wonder if Lee Renaud was thinking similarly when he decided to leave out the drag spars (rear spars, bottom spars) from the tip panels.
To my fluttery dismay and sadness years later on my fourth OLY-2 wing build.

 

[G-man]

Hmmm... looks like I added drag spars and shear webs to outer panels on #3 OLY-2 build, (spoilers installed).
No flutter ever detected on that (winch launch) airframe.

 

[Sandman]

Wayne
If they help with twist resistance in the tips, and don't add much weight, why not.
I was surprised how easily the tip panels on the Riser wing, can be twisted, due to the big open bays, widely spaced ribs.
As long as the poly hederal joint is solid, and the spar does its job, they might be unnecessary

 

[G-man]

Uh Oh, wing flutter during dive test.

Got some flying time in yesterday, working to fine tune my balance point.
It's too far back right now, and during the dive test the plane got pretty speedy.
WHAMMO - full tip flutter on the Sig RISER-100 wing.
Quick, strong pull-out stopped the flutter immediately. No damage observable.
That wing is strong (designed in the winch-launch times) but it sure didn't like going that fast.
The bendy balsa is quite some building material. Not a surprise that it's been used to make model airplanes for 80 years or more.

I am in favor of the anti-twist diagonals running all the way out to the tip on the new Aloft balsa 2.5 meter wing.

// Dave

 

[Wayne]

Pretty sure the design in ready for a test build. Currently working on the build plans and then exporting the parts for the laser. Probably not able to cut any parts for a while as we have so many other jobs running through the laser right now.

 

[Wayne]

Sorry so much time has slipped by. The laser has been pretty well booked making existing products, so had to wait to get my samples for this project.

I have to say I am excited at how well it is all going together for this first dry fit! I forgot to modify my second rib, but the rest are spot on. Need a tiny adjustment on the shear web to allow the ribs to sit a little higher up and we are golden. Spar caps slips right in. Super stoked.

 

[G-man]

Wayne>Super stoked.

Me too.
// Dave

 

[G-man]

Hey Red,
I've been working on my MINI WANDERER, but I had to put it aside for a little while to
help out another PRELUDE project builder with some work on his pushrods installation.
He had a tree fall on his house and repairing that cut into his model building time.
// Dave

 

[Wayne]

Stayed a little late tonight and glued her together. This is just a test panel, probably not going to fly. Glued with thin CA to test strength.

Nice tight joints:

Added a few pins and added some glue.

Will pull it off in the morning and glue the upper cap to the web. 3D print is not glued yet, need to add the sheeting for spacing.

We shall see what tomorrow brings! That and we ran out of 3/32" balsa, so can't go much further until our restock arrives.

Woohoo!

 

[Wayne]

Ok snuck in a bit of time here and there, and another hour or so tonight. The slowest part is sheeting bay #1. That took longer than building out the outer wing panel.

So far everything is looking pretty darn good.


The spar is super strong even though I'm only using thin CA.

The flush mounting screw turned out great.