Last Dec. MAC333 started a thread on this conversion, ran 3 pages then dropped out of site. Has anyone else converted this plane?

Yes, I have one. http://www.rcgroups.com/forums/showthread.php?t=1727496

What would you like to know? I didn't take pictures during the build, but I can take some pictures later and post some details. It could have been done much better, and if I did it all again there's things I would do that I could discuss as well.

Here is a new thread in the sport plane forum.

http://www.rcgroups.com/forums/showthread.php?t=1727496

Yes there is, and it probably should have been in this thread. What I was attempting to do, is find out what happened to MAC333's thread, and if there were any updates. Was the project completed,etc.? The monitor has not allowed that thread to be posted to since it is too old at 7 months.

I heard from MAC333, and he reports no recent progress due to other pressing matters. I was most interested in his project since it was my intention to do a similar build. I debated whether to buy a ARF and convert, or to track down a kit to better make the changes necessary to electrify. I got a lead on a kit from another thread, a plane called a" Utter Chaos 40" from Bridi, BluejayAirplane Kits.
With kit in hand, I started.
I had 2 motors on hand to use along with an esc and seperate bec. The motors are a U3520-6, a A4120-7 and a 60 amp esc all from BP hobbies. My plan was to power with 6s A123. I decided to build with the A4120-7 in mind since it is the heavyist, my experience with this sort of conversion is that it usually ends up tail heavy and felt the heavier motor was best. We shall see.
The build is pretty straight forward with some significant changes. First, I decided on a tail dragger, and second, felt it desirable to alter the front end to accomodate the electric motor.

Arnie
Would be interested in seeing your taildragger modification. I've been messing with a plan for what amounts to a 'large scale model' of a Kaos, at around 48 - 50" span, for too long and need to shift it some.

I've only owned three trike gear models since learning to fly RC in 1979. Though I love the shape and style of the Kaos, I've been torn between what I prefer and how the model looks with a taildragger set-up. My usual fuselage mounted bent alloy gear tends to look a little tacky and atypical. Not sure if I could be happy with wing mounted wire gear, though that is a little more 'period'.

The front end around an electric motor will be interesting - am resisting temptation to research a typical era two banger and how to make a dummy version At least the basic shape of the fuselage bodes well for a battery hatch.

Why a large scale model? Being a tightwad who used to fly 25 glow powered models because they could blow 40 powered ships off the map, were smaller and cheaper and used less fuel, my biggest batteries are 4S 3600mA which do fine at propelling 50"-ish models of four pounds or less at 'adequate' speeds But they ain't enough for the size and weight of the Kaos BARF from Tower Hobbies.

D

Dereck. I will have photos as I go along. I have not been sucessful in uploading to my threads, and have not been able to figure out what I am doing wrong. Once able to do so , I will be adding them to the thread.
As mentioned in my post, the lead to the Bridi I got from your posting over on the Sport Model thread for the Kaos.
Arnie

I think I have solved the upload problem, at least it worked in the Test section, so I'll try again.

Good going Arnie, the shots look fine.

How's the Bridi kit? He seems to be the source for models from that slinky era.

Balance is an interesting topic. Converting a glow model usually involves shuffling things forwards to compensate for our lighter motors. Thing to watch is being able to easily maintain the CG if you fly with batteries of different weights.

The front end conversion? Mount your motor on the design thrustline with the prop in the design location or maybe a tad ahead for balance purposes. Then create a lot of balsa dust by building a wooden cowling around it.

The attached, hopefully, show how it can be done on Sig's 4*40 kit. Should translate to your fuselage with a little ingenuity.

Hope that helps

Dereck

Dereck. Appreciate the suggestions, they are good food for thought. I have built, or attempted to build, about 10 kits from many different suppliers over the last several years, and I would rate the Bridi kit right up at the top of the list.
The instructions are very good, but lacking any visual assistance. But to anyone who has previously built a kit, they are more than sufficient.
All tech bits,ie laser cut, are very precise and carefully packaged. The kit only lacks small things like hinge material, tires, engine mount( which I didn't need anyway) and control links to be complete.
Arnie

In deciding to build as a taildragger, as mentioned in post #5, I failed to mention a couple of points. First, the Bridi plan does show this model being built either as a trik, or t.d, and details the position changes to the wing ribs to accomodate. However, as Dereck mentioned, I also did not want the lg wing mounted, and decided on a fuse mounting to be just ahead of the wing leading edge. Strictly a personal preference, but also for easier storage and transportation.
I set aside the fuse, started on the wing. I wanted to be abe to easily ensure the fit between wing and fuse before finishing the fuse. I also chose to make shorter ailerons and to wing mount the servos, eliminating the torque rods.

Hi Arnie
Thank you for the reminder on how a wing mounted UC can be a storage PITA! A fuselage mounted UC is far simpler, lighter and less fuss.

Good choice on wing mounting the servos. My first try with that was the Four Star I built in 1998, and I've built one model with torque rods since - and they got torn out and replaced by wing mounted servos in very short order!

Sorry about the quality of the attached, but this is my generic route to a wing mounted aileron servo. The hatch is nothing but 1/16" balsa taped over the servo bay. It puts the servo arm and aileron horn in the same plane of rotation, all that's out in the breeze is the pushrod, a little of the servo arm and the aileron horn and the hatch is non-structural.

After much testing on models with 40-odd ounce nicad batteries, my favourite UC mount for this configuration of taildragger turned out to be 3" or thereabouts lengths of 1" alloy L section, from a local hardware store, epoxied to the ply doublers to take the UC bolts.

If you need a custom UC, 'TnT landing gear' do reasonably priced custom jobs that will take all you can sling at them. www.tntlandinggear.com No personal influence there - I'm just a happy customer of theirs.

Hope that helps

Dereck

Thought I could add these how-to images of wing mounted servos to my previous post.

Oh well, never mind.

Hope they help, or even make sense!

D

Hi Dereck. Since I'll be using std servos, access to the mounting screws would be a bit dicey. I will probably just use the face mount method, even tho they look messy. I have a LG. from an ill fated Sig Something Extra kit that looks very nice, to my eye, on the fues. so i will go with that. Should have the basic wing ready for covering tomorrow.

Standard servos - thought they were all in museums now!

Recent words on Kaos UC location suggests I'll trade in those plentiful ply reinforced wing ribs for mounting wire legs to for a bent alloy sheet fuselage mounted gear, like wot I understand...

First big snag for trike gear for me - you have to buy three wheels. Yes, my wife's right - I am a tightwad

Have noticed a variety of tailfin/underfin shapes on Kaos/Chaos various in my ramblings. Some have just a tailfin with the rudder ending at the bottom edge of the fuselage, others run to substantial under-fuselage fin areas with the rudder going below the fuselage bottom also.

Suspect (A) It won't matter a hill of beans and (B) I'll do the most complicated version ...

D