ericrcpilot

My Feedback: (145)

The engine from Topnotchkits is awesome. I highly recommend it.

ericrcpilot

My Feedback: (145)

Here it is on my Balsa USA 1/4 scale cub.

cubcrasher

My Feedback: (6)

Wow, I like that.

martair

Yep...that is awesome!
Added to the list!

GerKonig

I have both, the 1/4 scale Sig Clipped wing, and the Balsa USA. The Balsa USA is much more scale than the Sig. Will post a picture later (have to go to the shed and take the picture first:-)

I did a couple of changes to the Balsa USA. I installed a tube, that allows you to easily mount the wings w/o help. I build the tail section so you can take it off (I transported the 1/4 scale cub in my Nissan Sentra). I overhauled the Balsa usa a couple of years ago. It is over 20 years old.

I have the 1/4 scale Sig for Sale. The Balsa USA has a Quadra 42 (still the original one). The Sig flew with a 1.08 2 stroke, then I flew it with a G-26, now it is electric:-)

Gerry

martair

Thanks Gerry for sharing your experience!

There we go again SIG versus BUSA!

I must say, generally I have a very good eye when it comes to shapes and outlines. There is people that say the BUSA is more scale, there is others that say the SIG is spot on!?!?
When you say the BUSA is more scale, what do you mean exactly?? Is it the outline...the details, the measurements??
I mean there is so many aspects! I am looking mostly at the outline of the plane and if it looks right. I have seen thousands of pics in the last days, and honestly the SIG looks closer to the real thing to me!
Doesn't the BUSA have an awe full lot of dihedral? I think even the SIG has too much too!?
I would love to follow (is it Robert's??) suggestion to buy plans and build form scratch but that is literally impossible here in Dubai! Everything has to be brought in, good quality wood is just not available!
Carbon, aluminium, brass....negative!! Even epoxy resin I am bringing in from Home in Switzerland.
If anybody wants to comment again on the SIG/BUSA thing please do so! It will certainly be interesting if someone has more insight!
Did anybody do some measurements? Did anybody print out the fuselage in 1/4 scale and compare it to the model?
Would be interesting to know!
Anyway, I think I am set on the SIG for the moment, but considering maybe the 1/3 scale from BUSA later. Or AMR...or??
Nice sharing thoughts with you guys!

As for now I have ordered the scale gear and wheels from Robart.
I also tried to cut pinked edge tape since I have a nice vinyl cutter. Not that easy since you have to fix the Solartex (or in my case Oratex) to some sort
of supporting paper to cut it. But on the other hand why bother if you can buy it at a reasonable price!?

Looking forward to some more opinions...

Cheers, Martin

acerc

Martin, buy one of the kits and a set of cubmans plans. Use the kit as a resource for the lumber and such but build to the scale plans.

GerKonig

And here are the pictures. One of the nice things of the Balsa USA is that it has a door. No big deal to modify Sig's version and add one. But it does nor come with the kit. It appears to me that some dimensions of Sig are a bit smaller. We still have snow on the ground, so, they will stay where they are. But, again, maybe it is a personal preference... I do not compete with any of both models so the "scale" issue is irrelevant to me. Both look their part in the air:-)

Balsa USA is white, Sig yellow. I did some upgrades to the Balsa USA. I installed 2 tubes in the wings. This way it is easy for one person to set up the model at the field. At the time, carbon fiber tubes were not invented:-) I used brass tubes, they worked OK... I also copied a modeller that had a tail section you could take off. I was able to transport the 1/4 scale cub in a 2 door Sentra... You disconnect 2 clevis of the bottom tail braces, then you disconnect 3 clevis from the push rods, and then the 2 screws that hold the section on the fuse. Of course, my next car was a station wagon, so I never took off the tail section off again:-) But, it is doable. Besides with the chunk of iron in the nose I needed weight in the tail.

When I overhauled the model, I put the servos a the back. In the "old days" we could never do that because of interference...

Whichever you pick, you cannot go wrong. But, I like all Balsa USA products:-)

Gerry

martair

Thanks guys for your support!
All that talking and researching about the cub made me so keen on getting it soon, and in the air, that I will simply buy 2 kits!
One will be built according plan to get airborne quickly. Also gives me experience and insight into the model.
The other one will be built with the help of the cubmans plans. As scale as I want to go!
Another thing I will integrate into the first one already is a scale lighting system.
I am working together with a company in Switzerland that makes so far the best lighting system on the market!
There is nothing "cooler" here in Dubai then flying around at sunset when all the others are packing up.
I will order the 2 kits tomorrow and have them picked up. Hopefully they will be here in about 1 week.
Talk to you guys soon...

Martin

martair

Alright...the first kit was picked up yesterday and is on its way to Dubai!
A colleague will bring me the Robart Gear on Saturday from Dallas
I am also in the progress of ordering the dummy engine kit and the plans for the J-3 as well as the scale aileron.
Since I am looking into this thread I realised that the rudder (well, LOTS OF THINGS actually) on my World Models Super Cub is wrong.
It is in fact the J-3 with a straight line in the back.
So I started some wood work and did this:



Oh yeah...now that looks like a Super Cub Rudder...right!?!?
As soon as the kit arrives I will get on it. Changed my mind a bit and will certainly do some scale work on this kit already!

martair

Does anybody have a good source of detailed pictures of the interior of the J-3?
Specially the area where the wing meets the wind screen.
Also the roof window. There seems to be lots of different versions.
Small windows, bigger windows!?
Would be great if someone has some information!
Thanks, Martin

acerc

I was given a cd with more detail than I could stand. I can send you a copy via email or an sd card. PM me if you want it.

martair

Hi guys

It is 10:00 am on the 28th here in Dubai and the Fedex man just dropped a box! It was picked up in Montezuma on the 26th at 10:30 pm Dubai time.
That means it took only 35:30 hours, not even 1 1/2 days to arrive here!
I am deeply impressed! Wow!

Just opened the box and started to have a look at some things in my mind. Specially the installation of the electric motor and battery.
The weight of battery, motor and ESC will be around 1,2ks. Any advise from you as to where they need to be for a good cg??
Motor of course is a given!
My guess is that it is needed in the front. Specially since I will install the elevator servo in the back, right near the surface.
I intend to do a kind of scale linkage inside the fuse and pull-pull rudder.

My aime is to make it as light as possible (would love to have it under 7kgs (15,5lbs), with Oratex (similar to Solartex), stitching and painting.
Lights will also be installed.
The power train is laid out for slightly more then scale flying performance, this will be something to enjoy!
The design will be an assumed rebuild of a Piper in the traditional yellow, but with some modern elements (interior and lighting)
Wether it will be an American Version or Swiss is not yet decided! (I am Swiss by the way!)

Unfortunately work is calling and I am off to Singapore tonight, back on Thuesday morning around 1am.
What is more, need to do some urgent work at home as well for the next 3 weeks. I will however get going anyway, just at a lower pace.

Can't wait to get my hands on this kit!!

Wishing you guys a nice weekend, will be back soon....

Cheers, Martin

GerKonig

The batteries go on the floor of the cockpit all the way to the front. I made a sliding battery tray. Easier to show than to explain. I will send you pictures monday. The escape goes under the cowling. I have a 1.6 Tacon ($55.00 from Nitroplanes). Of course it is overpowered, BUT, mine mimics a super Cub, and you know they have some with more than 200 HP in the full size world.

If you got the Sig, mine did not have a side door. You will need a side door to replace the batteries.

Gerry

GerKonig

Martin, you can see some pictures of the installation of the tray in one of the pictures I posted with the ad, here in RCU. http://www.rcuniverse.com/market/item.cfm?itemId=967715

Have a safe trip


Gerry

martair

Hi guys

Back from my trip. Did a lot of thinking and planing on my cub. Also bought some 6mm Carbon tubes for the cabin.
I will divert from the method mentioned to convert to a scale door. I have my own ideas. In fact, I will divert in many ways
from the original kit!
But more about that later!

Can someone tell me the correct dihedral on a J-3?
I found 2 3/8 inch on the original, stretching a string from wingtip to wingtip, measured at the center!?
That would mean for the 1/4 scale cub around 19/32 of an inch (I will never get used to these units!!! )

@ Gerry
Thanks for your information. My motor will be lighter and so is the battery. Plus the elevator servo will be in the back.
So I guess that enforces my suspicion that the battery will have to be under the motor (which frankly is what I want anyway
so it is out of sight!
Wether I will insert it from the cabin or make the lower part of the engine cowling removable remains open.
Still some thinking and cleaning up to do before I can get started.
Meanwhile the dummy engine and the cub man plans have started their journey to the Middle East.

GerKonig

Well, the secret is to balance w/o having to add weight:-) Mine has no unnecessary weight added to balance, and I ended up putting the batteries inside the cockpit all the way forwards. Now, if you add a servo at the back, you will need to add weight at the front, and if you have a lighter motor, well, your batteries will have to be moved forwards, no doubt. Most likely on the firewall, under the cowling, it will work.

On the other hand you will have more details added, and most of those will be in the nose area. I would suggest using a Dubro landing gear for the cub. They really look pretty and enhance the appearance.

Those of us that fly big electrics have the battery that allows us to adjust the CG... I am working on a DVIII that I most likely will fly with 6 cells. But If I need more weight, I will put 2 6 cell pack on the firewall. In paralell, it will extend the flight time x 2:-)

Good luck with the project.

Gerry

martair

Yes, I will do lots of modifications. But I will not use the piano wires, they are way to heavy! I will more or less replicate the structure of the fuselage that carries and attaches the wings to the fuselage. That means braces from the front, thru the roof and then back down on the backside into the structure.
I will use 6mm Carbon tubes for that.
This way I can more or less get rid of all of the wooden window frames. I will of course not do that but rather make them of much thinner and stiffer material (plywood carbon sandwich).
I really want the cabin area to look as scale as possible!
Since I am not going crazy and all aerobatic I am not worried that the structure is not strong enough. In fact, I believe it will even be stronger then the suggested method.
But we will see about that later.
Hopefully I will be able to get started at some woodwork tomorrow. I will start with the rudder and fin, then the stabiliser and the elevator.
The elevator will get an internal linkage, invisible from outside. Requires some additional changes.
Also, the wood for the tail feathers is really heavy! I will use the same method I used on the rudder I posted before for my big Super Cub.
It is extremely light and stiff!!!
But one thing at a time.
I will post here as I progress!

Truckracer

My Feedback: (19)

Browsing this thread as I'm building yet another CUB! First going back to the SIG vs Balsa USA kit debate and which one is more scale ..... the answer is extremely simple! Neither is scale ... period! Before I started my current project I took measurements from (4) CUB kits .... SIG, BUSA, Hanger 9 ARF and the Bill Hemple ARF. I also had a pile of CUB 3 view drawings and measurements from a full scale CUB. All the dimensions went on a spreadsheet for easy reference. Frankly, the ARFs were more scale than either of the kits which surprised me. I visited with Mike Gretz back when the SIG kit was designed and he took measurements from Hazen Sig's clipped wing and other full span CUBs while designing the kit. But something went wrong in the process as when it went to paper, many dimensions changed though the overall outline looks pretty good. I wonder if they didn't change some things to allow for easier kitting, standard balsa dimensions and less material waste in the factory. To be extremely fair to all ..... not all full scale CUBs are the same! While the basic fuselage tube structure remains the same from there most have been rebuilt many times. Critical things such as window outline shape, wingtip bow shapes and placement, cowl fit and shape, etc. etc. all can be altered over time as parts are replaced. Then add to this, few of my 3 view drawing agree with each other .... even so called authenticated drawings don't all agree. Many have major mistakes and errors leading one to wonder if the person doing the documentation had even looked a full scale CUB. Many errors are repeated over and over again and I would guess this is due to people copying other's artwork. About the only way a person could have an authentic CUB model would be to pick out a scale subject and copy that particular airplane doing their own documentation. Not unusual for scale building.

My airplane is being build as an everyday, highly aerobatic, low maintenance flyer. I wanted a fairly scale outline though few scale details will be required. Utility over detail on this CUB. I already had one so I started with a SIG kit. I wanted to try to reduce the amount of painting required and decided to try to use a pre-painted fiberglass cowl and molded windshield from the Hanger 9 ARF. Of course I wanted separate wing panels attached to a short tube. This required major design changes to accommodate the ARF parts which were more scale than any of the kit parts. The fuselage had to be taller and wider. The front of the fuselage had to have less inward taper and the sheeted fuselage part in front of the windshield had to be lowered. The engine thrust line was also lowered as it is way too high on the SIG kit. Of course the SIG kit incidence problems were also modified along with changing the engine down and side thrust. As one friend told me, building a SIG CUB is the definition of scratch building so other than the drawing time, incorporating the changes really wasn't too big of a problem. This one won't have a door and all fuselage access will be through a top hatch that screws in place. The door just takes away too much fuselage strength this plane will need.

I won't bore everyone with all the additional details but some areas got strengthened and some areas were lightened or otherwise completely changed from the SIG kit ... such as the tail. Other than the addition of the wing tube, the wings are basically stock SIG kit with a few personal preference updates. The landing gear was going to be a Robart but that has been changed to sheet aluminum, lightened as much as I can. Its simply more durable for the hundreds or thousands of touch and go's this airplane will hopefully endure on a not so smooth grass field. Covering will be Solartex CUB yellow with just enough additional paint to match the ARF cowl, make the Solartex color more opaque and seal the covering. A light coat of clear over the whole airplane will seal the lightning bolt, etc. Oh yes, power will be a DLE 35RA. If anybody is interested, I can post some framed up structure photos or discuss additional details.

GerKonig

"Browsing this thread as I'm building yet another CUB! First going back to the SIG vs Balsa USA kit debate and which one is more scale ..... the answer is extremely simple! Neither is scale ... period!"

Nope, wrong answer. The question was which is more scale, we know non is scale:-)

Interesting message you seemed very interested in building a "more scale" cub, and then you are using an aluminum landing gear? Good luck with the build. A couple of buddies have the Robart landing gear. All of them like it, and all have the same complaint (the price). It really improves the appearance. I still have the original landing gear in my Balsa USA cub. I built that kit over 20 years ago...

Gerry

Jason 3-Danhakl

My Feedback: (10)

Wow what a wealth of information about the Sig clipped wing cubbies! I got a really good deal on one of these kits last weekend at our local swap meet. I've built plenty of airplanes and look forward to this project.
I was wondering if any of you guys have thought about using one of the newer DLE 20 rear exhaust engines? It seems to me like that would be able to stay inside the cowling minus the needed airflow. I'm guessing
with proper precaution it should yank the airplane around very respectably. What you you guys think?

cubcrasher

My Feedback: (6)

This baby has a Magnum 180 in it, throws it around like a rag doll.

Truckracer

My Feedback: (19)

I bought the Robart LG and have it laying here. I chose the aluminum gear simply for its durability. It seems the scale gears always require maintenance and fail you when you most need them. The sheet metal will take a beating. I do like the scale gear very much ... just not for this build.

Which airplane is more scale you ask ..... can't answer that question. Would just have to compare the planes piece by piece to come to a conclusion and as I pointed out ..... full scale CUBS are not all exactly alike. Good thing we're not talking Taylorcrafts here .... they can be very different from each other.

martair

Hi Truckracer

Wow, that was very valuable information! Funny enough, as I mentioned before, I have a very good eye when it comes to shapes and the hangar 9 was always my favourite!
It just looks right!!
I am hoping with the help of the cub man plans to be able to do some changes towards a scale outline.
The engine cowl is easy to be reproduced and with the topnotch engine dummy it will look even better then the hangar 9.
I would love to see pictures of the structure of your cub!!!

John_M_

I have the robart gear, it looks pretty durable... I replaced the rubber O-rings with some real bungee shock chord and put a piece of 200lb test fishing leader wire as a means of restraining the travel on hard landings... don't see any reason why the gear would be hi maintenance.

The only thing I noticed about the robart gear, is its no where near scale... the real cub gear is 21.5" inches, center to center between the fore and aft pivot points, which @ 25% would be 5 3/8" inches... the robart gear is 4 5/8" inches, making it 3/4 "of an inch narrower between the pivots; which isn't a real big deal, until you go to add one to an already built cub... you either have to mount the gear back 3/4" of an inch, or mount it where Sig puts theirs and make a new set of struts ( that is if you want the rear gear pivot right over the strut mount on the fuse )... other than that, they got all the other dimensions pretty close to scale.

John M,