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Apr 14, 2019, 02:25 PM
Living on the Dark Side.
guitarcher's Avatar
I'd call that a win Kent. Well done.
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May 12, 2019, 09:20 AM
Everything's A Composite
Knoll53's Avatar
Thread OP
Currently trying to find a construction method to make it a 3 day build.

day 1 - cut cores, assemble parts, lay up spar with sandable fill over top spar cap.
day 2 - cut mylars, sand spar cap. lay up skins,
day 3 - cut control surfaces, install radio and linkage.
Plus "instant fuse" and I'm there.
Last edited by Knoll53; May 12, 2019 at 09:31 AM.
May 12, 2019, 02:50 PM
Carbon fiber is our friend
Steve C's Avatar
It sounds so easy when your write it out like that, but I know it's more work than it sounds! Hope it goes well. Looks good.

I know I like how the inboard elevator flies vs full elevons.
May 12, 2019, 03:37 PM
Everything's A Composite
Knoll53's Avatar
Thread OP
Quote:
Originally Posted by Steve C
I know I like how the inboard elevator flies vs full elevons.
Don't tell me...............let it be a surprise.

The Instant Fuse is half done.
May 12, 2019, 09:33 PM
Everything's A Composite
Knoll53's Avatar
Thread OP
Glass it up.

Not knowing how well this glass would drape around the curvy fuse, I just cut a bunch of strips and went at it. It laid down pretty well except at the nose, which is always a problem. The nose will get a balsa nose cone.

My fast and dirty approach is to use just enough glass to create a somewhat rigid shell once the foam is removed. Fly it, then reinforce the parts that break.

This is resin rich...........to say the least. Ready to fly.

hyper plank fuse (5 min 7 sec)
Last edited by Knoll53; May 12, 2019 at 11:59 PM.
May 13, 2019, 07:25 AM
Registered User
EdSoars's Avatar
Great video! the supporting ply base will be added to my next fuse layup. I've been using electrician's tape, but I will try your strips of shrink wrap. Did you heat the wrap to shrink it?

What happened to the nice pointy nose? If it were me, I'd go to a toy store and buy a rubber ball, cut it in half and glass one half onto the nose. But you land in sand: no need for bounce.

Anxiously awaiting the next video...
May 13, 2019, 07:40 AM
Registered User
EdSoars's Avatar
Couldn't wait for next video before butting in again. It occurs to me that the airflow around the outboard ends of the elevators is going to be messy... and may cause reduced elevator effectiveness.
So:
As long as you're making it a 3-piece wing, you have an opportunity for experimenting: cut out 2 thin elevator tip plates, like 1/32" plywood, to slip over the joiner and alignment pins. Then you could compare the handling with and without plates.

I have lots of ideas for other people's spare time...
May 13, 2019, 08:48 AM
You know nothing....
Stuart A's Avatar
Quote:
Originally Posted by EdSoars
Great video! the supporting ply base will be added to my next fuse layup. I've been using electrician's tape, but I will try your strips of shrink wrap. Did you heat the wrap to shrink it?

What happened to the nice pointy nose? If it were me, I'd go to a toy store and buy a rubber ball, cut it in half and glass one half onto the nose. But you land in sand: no need for bounce.

Anxiously awaiting the next video...
This seemed to work ok.Slice the foam,take out 2mm and add lt.ply formers.
May 13, 2019, 09:08 AM
Everything's A Composite
Knoll53's Avatar
Thread OP
Quote:
Originally Posted by EdSoars
I've been using electrician's tape, but I will try your strips of shrink wrap. Did you heat the wrap to shrink it?

What happened to the nice pointy nose? If it were me, I'd go to a toy store and buy a rubber ball, cut it in half and glass one half onto the nose. But you land in sand: no need for bounce.
That was not shrink wrap, it was food wrap. It was a start at laying the glass down to the foam, but I quit too early. It tends to just slide off of the nose. It all sanded down OK. I will go with a balsa nose or maybe the super tough floatation foam I picked up at the beach. Bounce is always a good idea. I like to hand catch.

The elevators are 3" wide in the chord direction. I think that effectiveness is a given. I hope to have linkage that will provide super fine control. Can always add plates later as you say. Keep those ideas coming.........before it's too late. I'm cutting foam today.
May 14, 2019, 11:07 AM
Everything's A Composite
Knoll53's Avatar
Thread OP

Foam Cutting - 2019


PREVIOUSLY my hot wire cutting system relied upon a battery charger power source that has 2 settings. THAT coupled with the proper length of wire would produce a hot wire somewhere in the needed range...................with a little experimentation. No, I do not keep and check detailed notes before I cut

So the first cut is sometimes a surprise. Especially if the wire is short. This spurred on a side project which provided a seemingly good solution, the addition of a dimmer switch. Now I can dail up any speed cut. Better !

Since I have yet to use a template twice, I just glued the templates to the foam and let them become part of the wing.

This the first time using this cheap white foam. It is hopelessly frail.

Hot wire with dimmer switch (1 min 13 sec)
May 15, 2019, 08:05 AM
Registered User
EdSoars's Avatar
I use an 18 year old FeatherCut wire bow, and a much older electric heater as my power source. Clipping the lead wires to different places on the heater coil provides the variable voltage.

I may have to try gluing templates to the foam: I have a drawer full of once-used templates.
The additional time it takes to make two sets of templates for each foam panel would be recovered when they get glassed into the wing, since end caps are needed anyway.
Good idea using nails in the leading edge to guide the hotwire. Makes for a consistent LE thickness.
May 15, 2019, 09:23 AM
Everything's A Composite
Knoll53's Avatar
Thread OP
So the electric heater is still working and you are able to tap power off of it simply by clipping on to the heating element? I must have missed the Watch Mr. Wizard episode where he went over this. Pretty clever.....and universal...........and without added costs.

Do the heating elements still get hot?...........and melt the lead insulation?

Of course to make two templates from one paper template only requires that you use 3M77 to attach two rough cut lite ply blanks together. Sanding to the line on a belt sander goes quick whether it is one layer of lite ply or two.

The giant nail that I used provides a lot to sand at the leading edge, which I like. Regardless of size, the nail is needed to get the wire started at the right place for the ever popular automatic cut.

Glueing the free templates to the foam blanks does introduce another opportunity for error, which is not the case with templates that rest on the building board.
Last edited by Knoll53; May 15, 2019 at 09:46 AM.
May 15, 2019, 10:36 AM
Everything's A Composite
Knoll53's Avatar
Thread OP
I like to keep a record of the lay up.........just in case something actually works. In this case, the white foam crushed under 17 inches of vacuum, so the airfoil profile is not stellar.......Good enough. This root panel should be able to handle some abuse. This is going to be a heavy ship.

Hyper Plank - root panel (2 min 23 sec)
May 15, 2019, 08:18 PM
Everything's A Composite
Knoll53's Avatar
Thread OP
The humble little half span spar is in. The wings will be skinned with rather heavy 1/42" thick wood veneer with backing. Should be strong enough to work as stressed skin for the outer half of the wing.

A few more epoxy sessions and it's a plane.

Hyper Plank spar / joiner lay up (1 min 20 sec)
May 17, 2019, 10:06 AM
Everything's A Composite
Knoll53's Avatar
Thread OP
Normally the alignment pin is just long enough to poke thru the adjacent rib. Just thinking............if it were longer, it could be used as a secondary joiner to transfer loads from the sub-spar. Not the case with this wing so much inasmuch as the sub spar is nothing more than foam and skins.

This requires a super parallel alignment pin.



Alignment Pin jig (0 min 30 sec)


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