Sportsman Aviation Sport Stik 40 ARF Low Wing - RC Groups
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Oct 28, 2007, 11:12 AM
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Sportsman Aviation Sport Stik 40 ARF Low Wing


Sportsman Aviation Sport Stik 40 ARF Low Wing Aircraft Review

By Ken Myers

Photo 1 (box)

The Sportsman Aviat Sport Stik 40 ARF Low Wing Aircraft was chosen for this project because it was the cheapest 40-size ARF I could find. It is imported and sold by Hobby People ( http://www.hobbypeople.net/gallery/127522.asp ) for $79.99 in 2006 and now, October 2007, $89.99.

The germ of the idea for this project actually began when I read about the TowerPro 3520-7 brushless outrunner motor on RC Groups. ( https://www.rcgroups.com/forums/show...=TowerPro+3520 ) I entered into that discussion thread about the middle of February 2006.

My goal was to do the least expensive 40-size conversion possible that would still have good performance. Earlier in the year I had given a talk to the Midwest RC Society about converting glow planes to electric power. I wanted to “put my money where my mouth was.”

The kit was ordered on April 26, 2006 and arrived in excellent condition in about a week or less. I was out of town, and I don’t know the exact arrival date. I had also ordered a couple of Hitec HS-85BB servos, a 12” servo extension (although a 5” or 6” is all that is needed) and a couple of APC props, an 11x8 Sport and 11x8.5E to go with this project. The total cost was $140.98 and the shipping was free.

I opened the big box at 5:25 a.m. on Tuesday, May 9, 2006. 24 hours and 23 minutes of working time later, spread over three days, the completed plane was ready to fly. I added another 80 minutes of time after the maiden flight on Saturday, May 13, 2006 to fix the hatch attachment and eliminate a motor vibration problem when at full throttle.

While the build time seems quick on paper it was 10 hours and 30 minutes on the first day, 10 hours on the second day and the remainder of the time spent on the third day.

The instruction manual was well written in “real” English with useful black-and-white photos. No plans are provided or needed. I did reverse a couple of the steps because I thought they were more logical when reversed, but basically it was built just following the construction guide with check-off boxes.

Of course there was some reengineering to do the electric conversion.
The box indicated that real Monokote® is used for the covering material. The covering was quite nicely done and only required one little area on the fuselage, right behind the wing, to be tightened with a Monokote® iron.

The first thing I noticed, when removing the individual pieces from the box, was the weight of the horizontal stabilizer. If you hit someone with it, it would most likely hurt them a lot and NOT break! It is one of the heaviest chunks of wood I have ever felt in a model in my life! While the manufacturer claims the kit to be made from “High-Quality Balsa, Light Plywood and Foam”, it is not like any balsawood I have ever used to build a model.

Photo 2

The most “radical” reengineering, and hardest work, was making the top of the fuselage into a removable hatch for easy access to the battery. There was an obvious line in the covering about 1/8” from the top of the fuselage, and I assumed the top of the fuselage to be 1/8” thick balsa. I was wrong on two counts. The top of the fuselage appears to be about 1/16” thick and balsa appears to be the wrong designation for the wood!

I tried to use a razorblade to cut through what I thought was the joint between the top of the fuselage and the sides. Even though it was a brand-new, sharp razorblade, it had little effect on the wood. I tried an X-acto knife with a new #11 blade. It had little effect on the wood. Finally, I used my Dremel tool with the little radial saw blade and succeeded in cutting around the top. Unfortunately my cut line was now 1/16” below the actual top piece, but I managed to get the top free of the formers and the hatch began to take shape.

As I said, this was the hardest part of the whole assembly. Red Econokote® was used to cover the raw cut lines of the hatch. It does NOT match the red “Monokote®.”

Photo 3

After the maiden flight, when the hatch left the plane on the initial takeoff run, I modified the hatch to what can now be seen in Photo 3. Besides the magnets holding the hatch on, a rubber band was added and some 1/8” balsa placed along the hatch to keep it from shifting side-to-side. 3/32” thick plywood was used as cross pieces on the hatch to keep the wooden hatch from “bowing”.

Photo 4

The motor extender is just a “[“ shape made from 3 pieces of plywood with 3/8” triangle stock in the corners. The extender is glued onto the original firewall, so that the motor is in the same position that the glow motor would have been. The distance is noted in the instruction manual. Four holes were drilled in the original firewall for the bolts to pass through. They matched the holes on the forward mounting plate. There is nothing too critical about the dimensions of the motor extender. It just has to be big enough to fit the motor and long enough to place the prop in the proper place. The screws actually bolt through the original firewall to the nuts. 1/8” plywood would be a good choice of material for the extender. I used 3/32” plywood and it “bowed” too easily.

Photo 5

The battery tray is just a piece of 1/8” plywood measuring just over 2” wide and 5” long. It is glued between the formers in the bottom of the “tank” compartment of the glow model and located under the battery shown in the photo. While studying this photo, notice the two Hitec HS-85BB servos for the elevator and rudder. A couple of cross pieces of 1/8” plywood were used to raise and mount these smaller than standard size servos to the original installed servo mount to match the preexisting plastic tubing for the pushrods. A Hitec HS-225 servo can be seen fitted to the original aileron servo mount which was modified by adding some 1/8” plywood pieces to fit and the original servo mount. I would recommend using a Hitec HS-85BB for the aileron servo as well, but I already had the Hitec HS-225. Do NOT EVEN CONSIDER using standard size servos in this conversion. They are weight that is not needed behind the CG (center of gravity). The FMA Extreme 5 receiver is held in place with Velcro® as shown. The plywood battery tray supports the Li-Po battery in place with Velcro® on the bottom of the pack and a Velcro® cross strap. The SR batteries 600mAh NiMH receiver battery ( http://www.srbatteries.com ) is held in place with Velcro® as shown for proper balance. The receiver battery wire actually runs under the cross strap holding the flight battery when in actual use.

A plywood plate holds the receiver (it doesn’t need to be as large as the one shown above and also serves as a rubber band attachment point for the hatch hold down. The photo shows a full-length piece of plywood, but that is not necessary.

Photo 6 below shows the cross pieces for the HS-85BB servos and the air exit opened at the back of the fuselage.

The cowl is made of 1/16” balsa for the sides and 1/8” balsa for the top and front with 3/8” triangle stock ahead of the motor mount extender and behind and along the front plate. The triangle stock allows for some rounding of the cowl. The cowl is covered with white Econokote and attached to the fuselage with white Econokote. It is open on the bottom.

Photo 7

The rest of the plane is stock except several holes drilled in the original firewall to allow in more cooling air.
Last edited by Ken Myers; Oct 28, 2007 at 11:41 AM.
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Oct 28, 2007, 11:13 AM
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Part 2 - Weights and Specifications:


Electric Version – all weights in grams
Wing bolts: 3.7
Wing joiner, wing nut blocks & servo tray: 19.2
Right wing panel: 306.6
Left wing panel: 314.5
Vertical Stab & Rudder: 52.1
Horizontal Stab & Elevator: 139
Fuselage: 257.9
Canopy: 18.1
Cowl: 10.1
Landing Gear: 67.4
Landing Gear nuts & bolts: 17.1
2 ea. Main wheels: 17.5
Tail wheel bracket, wheel & screws: 12.8
Epoxy: 84.3
Extra wood for hatch, Mtr mount & battery tray: 44.15
Complete Airframe Weight: 1034.95g/36.51 oz. (53.5% total wt.)

Onboard Radio System (ORS):
2 ea. Nylon control horns: 3.1
Aileron push rods, horns & clevises: 10.2
2 pushrod wires: 19.5
2 Hitec HS-85 & rails: 42.4
1 Hitec HS-225 & added servo rail wood: 35.6
TowerPro 60-amp brushless ESC w/wire, connectors, Velcro: 39.95
MPI switch harness: 11.4
SR Batteries 600mAh NiMH Rx battery: 65
FMA Extreme 5Ch Rx w/Velcro: 13
Complete ORS Weight: 240.15g/8.47 oz. (12.4% total wt.)

Power System:
Skyshark RC 4S1P Li-Po 4000mAh
w/ wire and connectors: 353.4
TowerPro 3520-6 brushless motor/w wire and connectors: 255
Backmount w/screws: 12.6
Prop adapter & setscrew: 17.6
APC 11x8.5E prop: 21.2
Complete Power System Weight: 659.8g/23.27 oz. (34% total wt.)

Measured Total Weight
Includes the weight that just creeps in:
2264.4g/79.88 oz./4.99 lb.
Wing Span: 51.75 inches
Wing Area: 585 Square inches
Fuselage Length: 44 Inches
Wing loading: 19.66 oz./sq.ft.
Cubic Wing Loading (CWL): 9.76 oz./cu.ft. (typical sport plane CWL)
Watts in per pound 5S pack: 5.25 lb. = 124 watts in / lb.
Watts in per pound 4S pack: 4.99 lb. = 95.2 watts in / lb.
Last edited by Ken Myers; Oct 28, 2007 at 11:55 AM.
Oct 28, 2007, 11:13 AM
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Part 3 Flying:


The Maiden Flight:

The maiden flight took place on Saturday, May 13, 2006 at the Midwest RC Society 5 Mile Road flying field. The temperature was about 50 degrees Fahrenheit with the wind out the east at about 12 mph to 15 mph. It was raining on and off all day. The maiden flight was taken between the showers.

The power system for the maiden flight was different than the power system noted in the specifications. The speed control was a Castle Creations Phoenix-45, the battery a True RC 5S1P 4000mAh Li-Po and the prop was an APC 10x6 Sport. It turns out that this prop was causing the motor to vibrate terribly at full power. The cure will be discussed later.
While I knew that the motor was vibrating very badly at the maximum RPM, I elected to fly anyway and just not use maximum RPM. On the initial takeoff run the hatch blew off, bounced off or vibrated off. The hatch landed in the wet grass of the runway and immediately warped the wrong way! (Both the warping and blowing off problems have now been fixed and noted above.)

Since the hatch was “nonessential”, I set the plane up for another takeoff run. The plane lifted out of the long, wet grass very easily. I immediately had to start some serious trimming. Whenever the sticks were centered, the plane wanted to roll to the left and dive. After several minutes of trimming, it was under control. Only a few loops and rolls were tried, but it was flying just fine at partial throttle, even the loops. I made a couple of “high” landing passes to feel out the glide and landed uneventfully after a seven-minute flight.

My first impression is that the Low Stik is going to be just the plane I thought it was going to be. There is plenty of power and it flies easily. I have actually reduced the input power by using the Skyshark 4S1P 4000mAh Li-Po pack.

On the Monday following the maiden, I found out that the vibration was being caused by my choice of prop. When I test flew the plane I was using an APC 10x6 Sport prop. It had been balanced, actually a couple of times, using my High Point Balancer. I checked it again for the third time and its twin for balance and they were both right on, but both props would vibrate like crazy when full power was applied to the motor. I then tried a balanced Rev-Up 10x7 wood and a balanced APC 10x7E and neither one of them caused the vibration. When running this setup with a 5S pack, it looks like the APC 10x7E is the best choice. (It is. That is how I use this same setup in my Sonic 500 when using the 5S 4000mAh Li-Po pack.)
I had talked to Keith on the Saturday of the maiden flight and mentioned the vibration before I flew. He told me that sometimes when a brushless outrunner is mounted as I have it here, it does tend to vibrate. It is better to mount it the other way ‘round. I do believe that the mounting was part of the problem. Also, the APC 10x6 Sport props weigh just over 31 grams while the APC 10x7E and Rev-Up 10x7 both weigh under 20g. I do believe it is a “rotating mass” problem as well.

That same Saturday I ordered a 4S1P 4000mAh battery from Skyshark RC, as I really didn’t want to press this motor as much as I was using the APC 10x7E. This is the second solution to the vibrating prop problem.

First Flights with 4S1P & APC 11x8.5E

The next three flights were on Saturday, May 20, 2006. The temperature was between 50 degrees in the morning and 65 in the afternoon. Winds were 16 mph gusting to 22 mph (really – that’s what weather service said when I checked at 3:20 p.m.). I loaded the Skyshark R/C 4S1P Li-Po, had the plane set on the runway and the first of three flights was on. It flew very well, even in the wind. Upwind speed was good and the power through vertical maneuvers was good. It lost a little speed and vertical when compared to the 5S pack, but it was now the inexpensive 40-size glow conversion that I was trying to do. The first flight was for 7 minutes so that I could check the state of charge of the pack. The battery was checked and recharged and the second flight was for ten minutes. Again the pack was recharged and I flew a 7-minute flight, just because I had had enough of the wind! It wasn’t that the plane had any problems flying in the wind or even landing. I was just tired of standing in the wind!

Photo 1
Last edited by Ken Myers; Oct 28, 2007 at 12:00 PM.
Oct 28, 2007, 11:14 AM
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Part 4 - The Power System:


The Motor and Speed Controller:

As noted earlier, the motor is a TowerPro 3520-6 (http://www.towerpro.cn) el cheapo, produced in China. (You get what you pay for!) I purchased mine from Milton at E-Flightbatteries, 135 Johnsbluff, Auburn, GA 30011 ( http://www.eflightbatteries.com/default.asp ). Although you will not find it listed on the Web site, an email to Milton will get you the ordering information.

At the same time I purchased a TowerPro 60-amp brushless speed control. Milton had a package deal that included the motor and speed control for $97.00 including the shipping. For the maiden flight, I did not attempt to use the 60-amp brushless ESC (electronic speed control) with the 5S pack, as I had read in the RC Group forum that this particular ESC really doesn’t like five cells.

The speed controller has been changed to this cheap 60-amp controller because I am now using the 4S1P 4000mAh Li-Po battery from Skyshark R/C. The cost of the Li-Po was $84.95 including taps and shipping. ( http://www.skysharkrc.com/shop/index.php?shop=1&cat=24 )

The Tower in TowerPro has NOTHING to do with Tower Hobbies and is just part of the name of the Chinese company. As a matter of fact, Tower Hobbies threatened to sue any vendors using the TowerPro name.

If you check the thread mentioned near the beginning of this article you would find that there are at least two winds for this motor as well as different parts, colors, mounting hardware, and mounting holes. You pay your money and take your chances!

One version of this motor has a Kv of about 600 RPM/volt (TP 3520-7) while the other has a Kv over 700 RPM/volt (TP 3520-6). It appeared that Milton was selling the one with the under 600 Kv, that is why I ordered from him, as I wanted to run it on a 5S pack, while the over 700 Kv version is best used with a 4S pack. All of the suppliers tend to list the specifications that the TowerPro site has posted about this motor. TowerPro’s specifications are wrong!

My tests:

I weighed the motor with the leads and Anderson Power Poles attached and it weighed 255g/9 oz. TowerPro and the various vendors give a weight of 237g/8.36 oz. A pair of APP connectors and pins weighs 3.35g. Draw your own conclusion.

First I did a drill press test to find the Kv. The drill press turned at 1560 RPM. The AC RMS was 1.59v. Doing the math yielded a Kv of 730.3894 RPM/volt. Dang. I was pretty sure I had the wrong motor!

Photo 1

I attached the motor to my bench test unit. It was interesting to note that the “+” style back mount matched the same hole spacing as the AXI 41xx series motors. My Castle Creations Phoenix 45 was set to the default settings and attached to the motor. My Hyperion Emeter was used to collect the data. As a check on the Emeter accuracy, an Astro Flight Whattmeter was also used to verify the volt and amp readings.

I was hoping that I had somehow “messed up” the Kv number. Optimistically, I started the motor testing by using a 16-cell 3300mAh NiMH pack. It is the same pack that I use in my Electro Flying Fusion ( http://www.electroflying.com ) sport plane. I mounted an APC 12x10 Pattern prop, ran up the motor and shut down immediately after reading 55 amps on the Emeter. I tried several different props all the way down to an APC 10x7E, which drew about 38 amps on 16 cells.

Next I used two 7-cell Panasonic 2000mAh packs hooked-up in series to do the actual testing. The cells were peaked and then 5 captures were made approximately 5 seconds apart for each prop. I started with the largest prop and moved down in size until all four props were tested and their data captured. Prop data for all four props were gathered from the same battery charge. Three sets of tests were conducted on the same day so that there are15 data points for each prop. The prop data was then averaged.

The Results:

Elevation: 224.3m/736 ft.
Ambient shop temperature through the testing period: ~16 degrees C
Barometric Pressure: 989.2mb steady
Dew Point: 14C
Humidity: 91% (It was raining all day.)

Average Results:
APC 12x10 Pattern, 12.743v, 40.93 amps, 8059.5 RPM
APC 11x7E, 13.778v, 30.75 amps, 9132 RPM
Rev-Up 10x7, 14.227v, 24.93 amps, 9666 RPM
APC 9x5 Sport, 15.254v, 15.86 amps, 10744 RPM

The No Load test was done right after the last of the loaded tests.
Average Results:
13-cells 15.87v 4.64 amps 11676 RPM
14-cells 16.78v 4.87 amps 12396 RPM

Li-Po Battery & Prop Tests:
5S1P True RC/APC 10x7E, 17.2v, 38 amps, 11224 RPM, 653 Watts in, Est. system watts out 502, system. eff. 76.8%
4S1P Skyshark R/C/APC 11x8.5E, 13.39v, 35.5 amps, 8610 RPM, 475 Watts in, Est. system watts out 372, system. eff. 78.2%

The above numbers can be put into the FREE Drive Calculator application ( http://www.drivecalc.de ) and yield the following.

Photo 2

It can be seen that Drive Calculator calculates the Kv at 736 RPM/volt when this data is used. That is pretty darn close to my generator constant of 730.3894 RPM/volt.

The Batteries:

The first battery I used is from True RC ( http://home.comcast.net/~truerc/index.htm ). It cost $85.00 for the 5S1P 4000mAh pack, $5 for the Poly-Quest type tap (which work perfectly with the Astro Flight Blinky) and $5.40 for the shipping for a total of $95.40. The cells are said to be rated at a true 10C (40 amps) with no burst rating given. When the pack arrived, I measured the resting voltage. Three of the cells were at 3.80v, while the other two were at 3.79v.

The pack was charged using my Astro Flight Model 109 charger. After charging, I attached my Astro Flight Blinky to equalize the cells. I then ran up the APC 10x6 Sport prop and read about 35 amps, which is what I was looking for. The battery was then used to do the initial flight test a few days later without any recharging. About an hour after the initial seven-minute flight, the resting voltage on all 5 cells was 3.81v.

The battery was charged with the following results; 21.00v, 53:53 Time, and 2.439Ah.

The battery weighs 468.3g/16.5 oz. with taps, wires and connectors. This pack is 535g/18.87 oz. lighter than the 16-cell 3300mAh NiMH pack used in my Fusion. I measured both packs in mm and converted the measurements to inches; 50mm W x 147mm L x 29mm T or 1 15/16” W x 5 13/16” L x 1 1/8” T. The manufacturer, True RC, says on his Web site that the battery weighs 425g/15 oz. I suppose that is without taps and connectors.

Photo 3 shows this battery

The second pack is a Skyshark R/C 4S1P 4000mAh Li-Po ( http://www.skysharkrc.com ). It weighs 353.4g with wire, taps and connectors. Dimensions, measured like above are 50mm W x 147mm L x 22mm T or 1 15/16” W x 5 13/16” L x 7/8” T.

Skyshark R/C gave very quick service. It was ordered on Saturday and arrived via the US Postal Service on Wednesday! It cost $84.95 with FREE shipping. The taps were included in the price and work with the Astro Flight Blinky right out of the box.

The resting voltage upon arrival was 3.82v on one of the cells and 3.81v on the other three. The initial charge lasted 53:57 Time to 16.80v and 2.141AH. After the initial charge the voltages were 4.18v, 4.15v and two at 4.16. They were balanced by the AF Blinky to 4.16v on one cell and the other three at 4.15v.

This pack was used to get the numbers for the APC 11x8.5E prop. This was done twice for a total of about a minute and a half of real runtime. The pack was then discharged down to 3.69v per cell using the AF 109 charger in discharge mode. The pack was then recharged with the following results; 16.80v, 1:09:31 time, 3.329Ah. The resting voltage ten hours after the charge was then measured at 4.16v, 4.15v, 4.15v, 4.16v. The pack was “Blinkied” to one cell at 4.16v and the remaining three at 4.15v.

Photo 4 Skyshark pack

Photo 5 Another angle of the completed model
Last edited by Ken Myers; Oct 30, 2007 at 06:00 AM.
Oct 28, 2007, 11:15 AM
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Part 5: Postscript


In the late spring of 2006, I did the “oops” that I’ve warned people about for years. I attempted to fly the Sport Stik with the wrong model selected on my Hitec Eclipse 7 transmitter. The results were predictable, a smashed fuselage. Dang. I’ve been extremely careful since then!

I built a new fuselage and continued to fly through the rest of the summer with it.

Photo 1 under construction

Photo 2 completed

In the fall of the year 2006, I had a switch harness failure and she once again went in, and once again, the only damage was to the front half of the fuselage.

The power system went into the Sportsman Aviation Ryan STA. The build thread for the STA is located at: https://www.rcgroups.com/forums/showthread.php?t=557165

The broken fuselage and tail are hanging on the wall of the basement with still good wing on the wing rack.

Will she be phoenixed again? I have no idea, since the Dymond RC Flite 40 takes her place in my flying stable. The Flite 40 build is located at: https://www.rcgroups.com/forums/showthread.php?t=735972

The only thing I know for sure is that if she does “rise again” she’ll be using a 5S M1 (A123 Systems) pack and a TowerPro 3520-7 with most likely an APC 13x9 pattern prop.
Last edited by Ken Myers; Oct 28, 2007 at 12:25 PM.
Oct 28, 2007, 07:18 PM
Visitor from Reality
Hi Ken
Now look what you've done. All I'd planned to do to my EFlite 32/UglyStiKlone this winter was tear off the EFlite angular vertical stab, replace it with a Phil Kraft lookalike and a couple of other oddments - like recovering the entire model, re-arranging the radio fit to correct its incorrect balance and so on...

Now, I feel I have to "reverse engineer" my readymade Stiklone to produce a dedicated electric Low Wing Ugly Stik lookalike!

Quick questions - how's that cheap-O motor holding up? and does this version of the Low Wing Stik have any dihedral?

I'd thought of tossing my EFlite Stik fus and building a low wing stik lookalike body for the wing and tail - my tailplane is a little lighter than yours - but the EFlite Stik wing has no dihedral and that never works properly on a low winged model, despite what marketting tries to convince us about.

And yes, I'd build my new "design" fuselage like yours, so it didn't have the motor hanging off an inch or two of extension. I have this thing about doing things correctly...

Other really notable points - that's the first photo of you I can recall seeing and it's also the first photo I've seen of a Stik with a cowling around the power unit, wet or dry!

Regards

Dereck
Also coming down heavily in favour of the A123 RBRJ (Really Big Round Jug)
Oct 29, 2007, 05:07 AM
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Quote:
Originally Posted by Dereck
Quick questions - how's that cheap-O motor holding up?
Fine, that particular TP 3520-6 is in the Ryan STA/STM mentioned above. The one that was originally in the Flite 40, the TP 3520-7, is fine also, but just doesn't have a home right now. When I started thinking it was the bearings in the Flite 40 report, it turned out not to be, but it has new bearings in it now. Oh well.
I have another TP 3520-6 in the Sonic 500, and it is holding up well. Remember, I do NOT run these motors too hard. I do my setups with a maximum static WOT of about 35 amps.

Quote:
and does this version of the Low Wing Stik have any dihedral?
Yes, I just went downstairs and measured it, 2 5/8" total.

Quote:
Other really notable points - that's the first photo of you I can recall seeing and it's also the first photo I've seen of a Stik with a cowling around the power unit, wet or dry!
Is that really me? ;-) I generally break the camera. I've added one of my favorites here with my flying buddy.

Actually, my very first electric was a Midwest Sweet Stik 40 and I added a similar "cowl". Power was an Astro Flight 25 Ferrite and 12 1200mAh cells turning a 9x?, most likely Master Airscrew prop, with an on/off switch for the motor operated by a servo. It was about a year later that I met my flying buddy who really got me on track.

Quote:
Also coming down heavily in favour of the A123 RBRJ (Really Big Round Jug)
For my type of flying and aircraft missions, they are what I've always wanted. I know that lots of folks like to fly for a long time, and that's fine, but I pretty much have a 6 to 7 minute attention span, so they work really well for me.
Oct 29, 2007, 03:34 PM
Visitor from Reality
Hi Ken
Have thought about a cowling on the EFlite Stiklone when I tear into it this winter - the plan is, loosely, to rip all the covering off, replace the fin/rudder with a round one, take out the entire interior, move the fuselage servos aft of the wing (yes, still on the inside!), replace the battery tray with one that positions the CG properly as the model is nose heavy mostly, put the aileron servos inside the wing, then recover it as either a Phil Kraft lookalike or maybe do it like the "opposition".

I've already traded the UC for one I had handy, and reduced the AUW by two ounces.

Now you see why I usually design my own models

it'll probably go to 4S 123 as well - six or seven mins is fine by me, though I do have a lipo fuelled indoor model that I get bored with before its 400mA lipo runs out - usually land after 12 mins or so.

Cowlings I like too - I have one of the few Four Stars around that had a cowling, though it required MaxCim's elegant motor mount to fit it in. A cowled UglyStik though ?

Right now, keep ambling through the options for what motors would be good with a 6S 123 pack. My now somewhat ancient Hacker B50 with epicyclic box is horribly noisy and doesn't really match the 6S pack - assessed by a somewhat less scientific method than yours - so am idly looking around the bazaar. Still like gears though - and have a boxful of MEC Superboxes I seem to have acquired over the years. It's one more thing that allows a little fudging if things don't really match.

Regards

Dereck
Mar 02, 2017, 10:27 AM
Registered User
I have the fuselage, tail and fin of this specific model. No wing, landing gear, possible missing motor mount. I do have push rod and parts and instruction. I have partial decals for this plane. I saved it from landfill after it was thrown out by the Hobby People that recently closed. I am selling it complete. PM me about it.
Last edited by Airwolf7; Mar 02, 2017 at 10:33 AM.


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