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Posted by GooberSB | Feb 22, 2014 @ 09:06 AM | 1,465 Views
Posted by GooberSB | Dec 19, 2011 @ 01:13 PM | 3,044 Views
I wanted to build myself an indoor flier similar to the 12" version I built for a friend but without the expensive PZ brick.

It's amazing how fast the weight goes up on a disc shaped aircraft. At 125% the size of the 12" version, the weight is about 300%.

I started out with a 5g hexTronik motor and a 350mah 2S but it couldn't keep it in the air at all. I switched to a 3S battery and could smell the wires melting in the motor after a few minutes of average throttle. I replaced the motor and battery with a hexTronik 2211 (250 size) and a 500mah 2S. That made a big difference.

Now, I've been using the 2211 on wings of various sizes. The 20" and 24" KESL wings (see my blog posts below on those) and a few failed builds fly great with these motors. But I wanted this one to be indoor not a fast outdoor flier. I learned from my Electrifly Pluma that a large motor with a large prop can fly extremely slow so that's the direction I went.

I put a 8x3.8 prop on this motor and went with a 2S to keep the rpms down. I don't want a lot of rpms this time.

Here's a video of the result. I'm flying on low rates because on high rates the axial roll is pretty fast. I think if I increase my expo from 30% to 70% I can fly it normally on high rates and be able to a good hover too.

16" Sport UFO (4 min 32 sec)

Posted by GooberSB | Dec 06, 2011 @ 09:41 PM | 3,137 Views
Hello! Greetings!

I finally got around to finishing my 48" UFO build. It took longer that I thought because I had a few setbacks, but first let me describe the project.

After building 2 successful UFOs and looking at lots of plans for Mantas, bi-planes with disc wings, and other oddly shaped aircraft that could be reduced to a flying disc at the most basic level I decided I wanted to try something large.

I knew the wing loading could be low - maybe 3oz / sq ft - but how low was to be seen. My first step was to buy the sheet of 8 ft x 4 ft 1/2" Dow bluecor insulation at Lowes for $12. The plan was to make this a KFm2 with the step on top being a semi-circle of 48" diameter.

I cut the full 48" dia circle and the semi-circle quickly. After fitting them and doing some tests I realized that the weight of the back half caused it to flex and bow and bend. Like a cattail on the end of a reed has a lot of leverage when the wind blows.

Then I realized I needed a strong spar of some sort to hold the back half of the craft straight and level with the front half. I used a 3 ft 1/4" wooden dowel from Michaels for this. Melted a trench into the center panel all the way along the center thrust line and glued the dowel in with hot glue and gorilla glue. Didn't have to be neat, just straight down the center. It would be covered later with the fuselage.

After glueing the spar down the center it was time to cover the front half with the 1/...Continue Reading
Posted by GooberSB | Nov 24, 2011 @ 09:53 PM | 3,318 Views
So I managed to maiden a new wing and fly an older one today. Several times. But I also brought out the 22" UFO and the PZ UM Pole Cat.

Man I like the Pole Cat. It is a fantastic little plane. I don't have a UM T-28 but I wonder if the Pole Cat is sutable as an aileron trainer if used with a good transmitter. I use a DX6i and set the ailerons to 45% for now. I admit I'm not that good - but I can still fly this plane. It's very light (runs on 3.7V) and will float like the Champ or fly like a pylon racer.


SB
Posted by GooberSB | Nov 24, 2011 @ 08:59 PM | 3,448 Views
I built a KFm-4ward on yesterday and just flew it today.

I put a ExceedRc Rocket motor on it with a 7x5 Master Airscrew prop and a 1800mah 3S lipo. This setup gives me over 200W at 20-25A. The motor can take 30A but max efficiency is only up to 18A. Balances nice and flies smooth on low rates. In this video I'm flying at 50% aileron and 60% elevator so it flares nicely at low speed landings as you can see at the end of the video. On high rates (100% throw) it will turn on a dime but I don't want that much throw when getting to know my planes.

It is a gentle giant on low rates and very maneuverable on high rates.

Here's a video of todays flight and some pictures

48" KFm-4ward (3 min 57 sec)


This is a nice flyby filmed Dec 17
...Continue Reading
Posted by GooberSB | Nov 24, 2011 @ 07:55 PM | 3,361 Views
Hello

Thanksgiving turned out to be a great day to fly some wings. A little bit of breeze kept the Champ indoors. But not the KESL.

I've been flying it for months and still enjoy bringing it out on days that my small planes would be blown around.

Heres a flight video.

It doesn't have a super powerful motor on it (I wanted about 800g of thrust) but it's still around 1:1 thrust/weight ratio. Not a speed demon at all. I fly on low rates most of the time and in this video. I have my low rates set for 60% aileron and 60% elevator for low and 100% for high. When I want to do some tight turns I switch to high rates for a little while and then go back to relaxed flight on low.

The KESL build thread by rdjay is in the Foamies Scratchbuild forum...

SB


42" KESL (1 min 34 sec)

Posted by GooberSB | Nov 21, 2011 @ 07:05 PM | 2,956 Views
Today was great for flying. Finally the wind was down and the temp was relatively warm (60 F or so).

I flew my 22" UFO this afternoonand this evening I flew it again, along with the HZ Champ and PZ UM Pole Cat. What a range of flying characteristics. All 3 fly differently but incredibly well.

SB
Posted by GooberSB | Nov 21, 2011 @ 06:44 PM | 3,366 Views
I wanted to see how small I could go and make something I consider stable. I've tried wings down to 16" and found that they are very unpredicatble at that size (other than predictably fast and unstable).

So I decided to try a 12" version of gpw's UFO. Based on my experience with the 22" version I theorized that if the wing area was kept at slightly better than a HZ Champ and the same electronics were used I could create something that flies at about the speed of a Champ but have the stability of a disc. That's how the idea came about.

Here's the result
12" UFO (2 min 3 sec)


It weighs 55.5g and the wing loading is just under 2 oz / sq ft. My target weight was 60g so I was happy to be a little under that.

The details:
6mm FFF circle @ 12" diameter
3mm $Tree semi-circle @ 12" diameter
Champ/Vapor ESC/Rx brick
Champ motor/gearbox/prop
Champ/Vapor CF control rods
Flyzone Playmate landing gear
450mah 3.7v lipo

This build has boosted my confidence after a failed build this weekend. Now I'm working on a Sky Ray build by gpw, a 48" UFO, and a KFm-4ward wing by ombudsman.

The build that failed? A very unstable butterfly shape based off a cartoony butterfly clipart picture I liked.

...Continue Reading
Posted by GooberSB | Nov 01, 2011 @ 01:00 AM | 3,146 Views
On Saturday I wanted to build something quick and did a 22" version of a UFO. Need a break from wings.

BTW, the wings I've had great success building and flying are from the KESL thread. I've done a 20" with a little more sweep than the plans, a 24", and a 42" version. I like all 3 of them so they are still in rotation. One of these days I'll get some video of all 3 to post on the thread. I haven't reported on my builds yet but want to say thanks with some video.

Same goes for the UFO. It flies really nice. I tried to get some video of it today but the hat cam was looking up and the plane was out of view most of the time. I need to work on the placement...

Edit:

Ok, I got some video of the UFO model. Certainly not the best but I've tried flying and filming with my DV camcorder and that didn't turn out well either.
So hatcam it is when I'm doing the filming and the flying.

USAF UFO (3 min 34 sec)


and some video of the 20" KESL wing

...Continue Reading
Posted by GooberSB | Oct 24, 2011 @ 10:50 PM | 5,018 Views
Went to the park today and flew my Champ, UM Polecat, and Mini Slinger wing. The conditions were just right.

I've read in the Polecat thread that the rudder doesn't turn the Polecat but that's absolutely untrue. I practiced turns using the rudder with a little up elevator, rudder and ailerons coordinated, and rudder only. At first my low rate for rudder was 60% but I gradually increased it until I got what I wanted. The final low rate for rudder = 90%, aileron=45%, elevator = 80%. Now it flies like a trainer haha. I'm flying it better than my Airfield T-28.

Anyway, while I was flying the Mini Slinger (it makes more noise than my scratchbuilt wings) a group of young children came over to watch. They looked to be from 4-8 yrs old. The oldest was a boy and he watched as I moved the sticks around. eventually came the dreaded question "Can I fly it?"

He had been very nice, observant, quiet, and not the slightest bit distracting - but I had to say no. I tried to be as nice as I could by reminding him that it's not easy to do and even dangerous. And I added that if he crashed it would cost me a lot of money. He was satisfied with that and didn't ask again. I do wish he could have though.
Posted by GooberSB | Oct 23, 2011 @ 11:41 PM | 3,078 Views
Alright. This is neither build nor rant.

Today it was fairly windy again. Great for soaring. I was outside flying my scratchbuilt 20" KESL wing to see how she performed. I had been flying for about 15 mins when I noticed a hawk overhead soaring in the breeze making lazy circles. So I circled around towards the hawk to see what it would do. It seemd to be curious but not threatened so it kindof stayed close to the wing but followed behind it. I thought that was cool but then I noticed two more coming over to have a look. Soon there were 3 hawks circling overhead slowly but clearly interested in my wing. After a few minutes the wind picked up and I decided to bring the wing in while it was still possible. The hawks left shortly after.
Posted by GooberSB | Oct 23, 2011 @ 11:17 PM | 3,094 Views
Failed projects so far:
16" David Wing
20" David Wing
18" Dead Simple Wing
Divinity Wing
SewSlow Wing
Air Hogs Titan bash

I've learned a lot from building these things even though they failed.

The first one I ever built was the 16" David. The electronics I used were too heavy, it was too twitchy, and I didn't know anything about expo and the magic of low throw rates. This was a mix that doom any build project.

I learned from this one that Kryon spray paint may be foam safe but it's still a terrible way to cover your foam. The tape sticks to the paint and not the foam. And spray paint don't hold on too well. Now I use a good airbrush to decorate my foam and spray adhesive to make the tape stick.

As for the 20" David, it was very fast but I couldn't get it to track straight ahead. It was very prone to deviate off course if left unattended. Not what I'm looking for.

The Divinity was my second wing build. If I tried it again today I'm certain it would do so much better than it did that day. My problem was I was new to scratchbuilding and had no idea how to do things like make a motor mount out of foam or plywood. I didn't know about all the various plastic mounts out there or triangle stock plywood. So my motor was barely glued onto the back of the wing. Whenever it came down with any speed and stopped abruptly, the motor maintained its momentum and would fly off. Of course, this was tearing the one layer of 6mm Dollar Tree readyboard....Continue Reading
Posted by GooberSB | Oct 23, 2011 @ 10:22 PM | 3,163 Views
So I've had several brand new Champs. And I've bought several fuselages to experiment with brushless motors. The stock fuse isn't suited for a motor that mounts from the back or front so you have to be creative when fabricating your own mount and installing it into the fuse. Mounting the servos required cutting away a little foam but the motor mount problem should be on an IQ test.

Of all the experimenting I've done on the Champ, I always enjoy flyng the stock Champ the best. Yes, the P-51 motor with a 5043 prop gives it more authority. So does a 5g Hextronik motor. But the scale flight characteristics, the docile and floaty flight disappears as more internals get replaced. I've since learned that when it's too windy to fly my stock Champ, I should just fly something else.


Mini Super Cub. There are some upgrades that should not be upgrades. Like the transmitter that comes with the MSC. Like the removal of the ACT sensors. Like a 2.4ghz receiver.

I also have 2 of these MSCs. One with the stock motor and another with a 24g blue wonder. I have one MSC that I outfitted with a brushed ESC, a HK DSM2 compatible Rx, 9g servos, and a discovery buzzer. No ACT, no cheap transmitter that is spring loaded to return to center. No sir. But the motor is stock brushed 180. And I use a 350mah or 500mah 2S battery.

The other MSC is similar except that I put a TowerPro 2209 or so motor in it. It balanced well since it's a heavy motor so I thought flight would be just...Continue Reading
Posted by GooberSB | Oct 23, 2011 @ 09:47 PM | 3,012 Views
Since I started flying rc aircraft with my son in January, we've gone through quite a few models. Taking the wrong path, buying cheap kits, having a great time and having some bad days too.

We live out of town on a 3 acre lot surrounded by other lots of various sizes. The 3 lots behind and adjacent are 10 acres so we have quite a bit of usable airspace to play in.

We started with a Champ (and keep going back to it) and a HZ Mini super Cub. Flew the Champ in a gym on weeknights and outside on the weekends. Even when it was snowing. Flew the MSC on more windy days. I flew it just today with a keychain cam for fun.

Then I got a UM P-51 for my son as he was getting very good at flying the Champ indoors. But I didn't realize how much different it would be. That didn't work out. So I got out an old SlowStick and we added that to our rotation. And an E-Starter later. The old EPS stuff just can't take a head on collision with a power pole, the wood pile, or the ground. The cowl area was pretty hollow after those. The E-starter is repairable if the damage is from the main wing back. The GWS firewall in these EPS planes is a 10mmx10mm hole in the nose. Once it's messed up you have to start adding your own materials to build it up again. I considered getting a replacement but it was too much work in the first place. After that, we tried a T-34 Mentor of similar quality. The motor was underpowered and not heavy enough to balance it. After a few crashes I put...Continue Reading