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May 01, 2019, 09:37 PM
Entropy is happening!
Jim.Thompson's Avatar
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Quote:
Originally Posted by kenh3497
This is looking very nice! Can't wait for a flight report!.............
Thanks Ken. I am aiming to have it finished for a June 10 flying meet out at my favourite flying site: Mt. Borah, Manilla NSW.
All going to plan, it will be maidened then.

Quote:
For what it's worth "A123" and "LiFe" are essentially the same thing with A123 being a brand name. Both are Lithium iron phosphate technology batteries.
Ken
Well understood Ken. I have read anything and everything I can come across regarding this battery chemistry. Especially all the threads posted by Vollrathd.
His sharing of a lifetime of experience in electronics has provided me with a good education on the subject of A123 cells and power requirements of digital servos and associated technology.
I have built one of his "Voltsagger" arduino devices and will do more (very good) and he has designed and electronic switch for me and others.

Jim.
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May 01, 2019, 09:42 PM
Entropy is happening!
Jim.Thompson's Avatar
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Quote:
Originally Posted by ErcoupeEd
......................................
Just imagine that he substitutes foam for balsa
I'm giving it a try myself. Construction is much quicker, lightweight and strong!

I'm also considering a large scale T28 with profile fuselage and 100 inch wing span.
Fuselage will be thick enough to house all the radio and electric motor gear.
Wing will be blue or pink foam hot wired wing , two piece.
No built up framework. Then sheeted with balsa.Much like a foam sailplane wing
Slots cut for wing spars
Flaps, ailerons.
............................
Possibly retract gear
Ed,
Are you doing a build thread on this? Or blogging the build?
I am interested in follow up details.

But "profile fuselage" on a scale plane? How can that be?
May 02, 2019, 02:46 PM
SINK HAPPENS !!!!
EeleyEagle's Avatar
Once again , looking good JIm.
I assume that you have sat the model level by propping up the rear of the fuse. How much prop clearance do you have ? It looks a bit borderline from you photo.
Andrew
May 02, 2019, 05:28 PM
Entropy is happening!
Jim.Thompson's Avatar
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Quote:
Originally Posted by EeleyEagle
Once again , looking good JIm.
I assume that you have sat the model level by propping up the rear of the fuse. How much prop clearance do you have ? It looks a bit borderline from you photo.
Andrew
Yes Andrew. Prop to ground clearance is about 60 mm when the fuse is level.

Edit: I just checked again and it is more like 70 mm.
Last edited by Jim.Thompson; May 02, 2019 at 07:22 PM.
May 07, 2019, 06:26 PM
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Covering.


I have now covered all the components. The tail surfaces and wing control surfaces are covered in 30 micron laminating film.
The fuse and wings are covered with 80 micron laminating film.
Both are of the variety that takes paint well. Not sure of the details; here in Australia it is often difficult to find out what exactly you are buying.
This is the stuff that our local bloke, Phil (Humphrey) supplies and is a pleasure to use.
May 10, 2019, 06:51 PM
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Silicone hinges and first painting done.


I have now run all the silicone hinges. I just used general purpose silicone as I've come to the conclusion this is perfectly adequate for all models except perhaps the high performance DS types.
I painted the rudder. The paint job went well, but I tried to sand off the masking fuzz on the edges of the red stripes before clear coating. That was a mistake, and I learned that it is not possible to sand paint on laminating film without joins and any peaks showing through.
I'll cover this again and paint with the white only. Then I will stick on red vinyl stripes instead of red paint.
May 11, 2019, 02:56 PM
Play that funky music right
kenh3497's Avatar
You red paint looks like it blead under the tape? Looks very nice otherwise! In a pinch I've used vinyl electrical tape. It gives a nice clean edge. Best is a dedicated vinyl trim tape.

Ken
May 11, 2019, 05:25 PM
Entropy is happening!
Jim.Thompson's Avatar
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Quote:
Originally Posted by kenh3497
You red paint looks like it blead under the tape? Looks very nice otherwise! In a pinch I've used vinyl electrical tape. It gives a nice clean edge. Best is a dedicated vinyl trim tape.
Ken
Yes Ken. I plan to strip the rudder, re-cover and paint white. Then I will stick on vinyl strips.
The actual bleed through was minimal, as I shot a coat of clear over the masking tape before spraying the red.
The problem developed when I tried to sand off the masking fuzz (for want of a better word), before clear coating it.
It is not possible to ------- a laminating film covered part without any peaks showing through. That is just what happened.

Edit: What I meant to write there was; it is not possible to sand after painting and the overlaps and framing peaks etc. show through.
Last edited by Jim.Thompson; May 13, 2019 at 04:09 AM.
May 13, 2019, 04:19 AM
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Some paint on........ a bit rough, but hey, I'm learning to use this covering.


I am learning to use the laminating film; it required very careful going over several times before painting. Especially the edges and small wrinkles at framing intersections.
I am reasonably satisfied that with a bit more experience using it and painting it, that it will make a suitable product for this application.
This job is a bit rough, but then, I'm getting a bit rough and ready in my old age. Besides, it was never intended as a show queen; it will be a workhorse towing gliders, all things going to plan.
For the scale aficionados among you readers and fellow flyers, a word of warning:
I will not be cutting out a cockpit and most certainly will not be fitting a pilot................

I did a tentative weigh in tonight in the shed.
So far, it is 6.6 kg +- 50 grams or so. The exhaust header and muffler has not been made and fitted yet.
So, I am still in the running to achieve and AUW of under 7kg.
The Aus regulations state that a model is weighed "dry". Does that mean without batteries I am wondering? Or just without fuel?
May 13, 2019, 06:03 AM
SINK HAPPENS !!!!
EeleyEagle's Avatar
Looking sweet Jim.

Aircraft is weighed dry which means "Ready to fly, minus fuel " so Yes with batteries fitted, balanced and ready for take off so to speak.
Andrew

PS: Remember that you balance your model without fuel in the tank so essentially it will be nose heavy with a full tank of fuel and the balance slowly changes as the tank empties. If I remember correctly though, you placed your tank above the C of G so won't be of a concern to you .
Last edited by EeleyEagle; May 13, 2019 at 06:07 AM. Reason: Extra info added.
May 13, 2019, 06:24 AM
Entropy is happening!
Jim.Thompson's Avatar
Thread OP
Quote:
Originally Posted by EeleyEagle
Looking sweet Jim.

Aircraft is weighed dry which means "Ready to fly, minus fuel " so Yes with batteries fitted, balanced and ready for take off so to speak.
Andrew............
That was my assumption. However, what if it was an electric powered model? The batteries would equate to the fuel, would it not?

Quote:
........................ If I remember correctly though, you placed your tank above the C of G so won't be of a concern to you .
Yes. You know how I don't like nose heavy models......................

I did a very approximate impression of the CG as the model sits now. It is darn close; the exhaust header will move it slightly forward. I can fit the relatively heavy A123 battery just about anywhere for the final balance. It will require no lead.
Thanks Andrew!

Jim.
May 22, 2019, 06:47 PM
Entropy is happening!
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Acrylic lacquer blushing.


I have a compounding limitation on the spraying acrylic lacquer in our mostly high humidity environment.
The growing trees that are shading my yard are making the matter worse; the grass takes longer to dry out.
I tried spraying the underside of the wings earlier this week, but the paint blushed.
There is dryer weather coming though; I might get the tops of the wings done this weekend or early next week.

Meanwhile, I have been struggling with my new Taranis with view to using it to fly this model.
Only last night, very late, I had a breakthrough and got all 8 channel functions operational in my Taranis.
It's all untidy in the picture, but it all works.
I can now fit the electronics permanently and fit switches, batteries etc.

Jim.
May 28, 2019, 12:10 AM
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Muffler


The muffler is ready to mount. I rolled the tube and the cones from 1 mm sheet. It was surprisingly easy actually.
Ryan in at our local Aluminium specialist welding service welded it for me.
I will need to go back and get him to weld on some mounting straps. I will need to cut and bend them and provide with a set up jig first.

A question for Scott and any other readers who might know:

Is the radiant heat from this muffler likely to damage the paint and covering film on the side of the plane? It is, or will be, around 20 mm from the side.
That is a little over 3/4 inch.
If so, I might have to add a curved reflector shield.

I test ran the engine on the bench. It was loud, but otherwise ok. I did not check the RPM, but it sounded like it was similar to other exhaust systems I have tried on it.
The noise will not be a problem out at Mt. Borah, where this model will be mostly flown; we have a full size landing strip to fly on.

The Kioritz starts easy and runs nicely. I switched it off after a short run, then went next door to talk with pal. I came back several minutes later, turned it on and it started first flip.
May 28, 2019, 12:46 PM
Scott
Pylonracr's Avatar
Jin, I would not sweat the heat. If you leave the engine running for a long period of time stationary maybe, but flying the air flow should keep it cool. I have run mufflers and pipes a lot closer than that and never had a problem.

Scott


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