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Jim Young
Aug 13, 2004, 01:00 AM
!Introduction

| spec2
| @907121
|> <b>Wingspan:</b> |< 29.75"
|> <b>Wing Area:</b> |< 134 sq. in.
|> <b>Weight:</b> |< 9.5 oz.
|> <b>Length:</b> |< 20.5"
|> <b>Wing Loading:</b> |< 10.2 oz/sq. ft.
|> <b>Servos:</b> |< 2 HS-55
|> <b>Transmitter:</b> |< <ahref="http://www.airtronics.net">Airtronics Infinity 660</a>
|> <b>Receiver:</b> |< <a href="http://www.hitecrcd.com">HiTech RCD Micro 555</a>
|> <b>Battery:</b> |< Kokam 2S 1020mAhr LiPo
|> <b>Motor:</b> |< Speed 180, 2.9:1 gear box (incl)
|> <b>ESC:</b> |< <a href="http://www.electrifly.com">Great Planes Electri-Fly C-10</a>
|> <b>Manufacturer:</b> |< <a href=http://www.sigmfg.com>Sig</a>

While at the 2004 Toledo show, I wandered into the Sig booth. There, perched above some other park flyers, was the Lil' Rascal. This thing was too cute, and I had to have one. Among the piles and piles of foamy or "road kill" park flyers at the show, here was an honest to goodness model. I've always liked the Rascal line of models for their clean, classic lines, and all-around good looks. According to Sig, the Lil' Rascal has a nice power-to-weight ratio and is capable of handling higher wind conditions than your typical park flyer. So let's see how well Sig did in producing a Lil' Rascal.

!Kit Contents and Highlights

@907122:Good things come in small boxes.

@907123:Everything comes packaged in it's own plastic bag.

@907124:The workmanship is excellent.

The kit comes well packed, with everything in it's own plastic bag and taped down where necessary. As you open each bag, the workmanship of this kit becomes apparent. The one-piece wing has cap-stripped ribs, full D-tube construction, and is nicely covered in the classic Rascal white and transparent blue (or red) Oracover. The fuselage is built-up of balsa with some plywood here and there. The rear stringers are visible through the transparent covering and help to make it light and strong. The Speed 180 class motor comes with as JST connector and is pre-installed along with a 2.9:1 gearbox. The gearbox is an open frame type of aluminum construction and brass and plastic gears. The motor has a printed circuit board attached with three caps for noise suppression. The tail feathers are built-up from laser cut balsa and covered with Oracover. A complete set of hardware including the propeller and prop adapter rounds out the kit.

@907125:The workmanship of this kit is apparent by the structure added to the battery compartment cover.
@907126:The tail feathers are light and strong.

The ten page manual covers all aspects of assembly and has 22 photos/drawings to aid the builder along the way. Sig lists all of the radio and power equipment that they used and gives alternate suggestions.

!!Required Items
*What you will need:
*Micro receiver
*2 HS-55 (or similar) servos
*4A to 6A ESC with JST connector
*7x350mA NiMH or 2S LiPo battery pack

<b>That's it, the kit is that complete!</b>

!Assembly

!!The First Evening
I came home on afternoon, and discovered that my Lil' Rascal had arrived. After eating dinner, playing with the kids, and putting them down for the night, I headed down to the basement at 9:30pm. I quickly scanned the manual, collected the servos, receiver, and ESC and dove in.

The first order of business was to go over the covering with a warm iron. Changing humidity levels can cause balsa to shrink and expand, causing the covering to wrinkle a bit. My kit had a few wrinkles and only took a few minutes to tighten thing up. The elevator had a bit of a warp to it, but it was easily straightened out with a warm iron.

@907127:Two HS-55 servos fit perfectly into the servo tray. Notice the blind nut for the wing hold-down bolt. There were z-bends on the pre-installed control rods and they are hooked up to the servos.
@907128:The stabilizer was glued in place with 5 minute epoxy. I took a few seconds to trim the covering on the bottom of the stabilizer back to the edge of the fuselage to give a larger gluing area.

The manual called for the elevator CA hinges to be permanently attached, but after tugging quite hard on the elevator I realized that Sig had already done this for me.

<b>HINT:</b>I suggest that you punch some pin holes in the covering around the control horns so the glue can bond with the wood. Similarly, harden the pre-drilled holes for the landing gear wtih thin CA.

@907129:The pre-assembled ABS wheel pants were held in place with clear plastic pieces.
@907130:The landing gear came with two aluminum mounting tabs installed and is screwed to the bottom of the fuselage.

While the stab mounting epoxy set up, I skipped ahead in the manual and assembled the landing gear and wheel pants. All I had to do was thread the wheels and pants on to the wire landing gear. They were secured in place by gluing two pieces of clear plastic over the wire -- simple, but effective.

By now the stabilizer epoxy had set up, and I could glue the fin in place. The fin was keyed to fit into the stabilizer and had a slight bend in the bottom edge that matched the angle between the fuse and stabilized perfectly. I trimmed the covering back from the key, and used CA rather than epoxy to glue it in place.

@907131:The radio compartment is not roomy, but everything fit fine.
@907132:I used a Micro Lite antenna from E Cubed, and taped it to the underside of one of the wing panels to keep it away from the metal pushrods.

The receiver installed in front of the servos and was held in place with some Velcro. The servo and ESC leads were routed through a hole in the compartment floor. The manual described how to make a "bobbin" out of some balsa to shorten the receiver antenna. Rather than mess around with this, I ordered a Micro Lite antenna from Azarr at <a href=http://www.ecubedrc.com>E Cubed</a> and installed it on my receiver.

@907133:The ESC just "floats" in the battery compartment.
@907134:A Speed 180 motor/gearbox came pre-installed.

!!Battery Selection
I soldered on a JST connector to an ElectriFly C-10 ESC and plugged it into the motor. I had a 2S Kokam 1020mAhr pack available and it fit perfectly in the battery compartment. I used the supplied Velcro to secure it to the compartment cover. Sig called for a 7x350mAh NiMH pack, but just about any two cell LiPo pack is a good substitute. I would caution against using a three cell LiPo pack because you risk burning up the motor.

<img src="http://static.rcgroups.com/articles/ezonemag/2004/apr/lilrascal/clock2.gif">
At this point I had one and a half hours into the project and called it quits for the night.

!!Day Two
@907135:The push rods were bent at the tail and used plastic keepers.

The next day at work, I used a sharp hobby knife to cut out the decals. When I got home I ran downstairs and started to bend up the push rods, making sure I put on the plastic keepers first. A 6x4 propeller was included in the kit along with a collet type spinner.

<img src="http://static.rcgroups.com/articles/ezonemag/2004/apr/lilrascal/clock2.gif">
The Lil' Rascal was ready for it's maiden flight in less than 2 hours from opening the box! I did not need to add any hardware, or feel the need to replace any of the hardware supplied.

@907136:The decals really dress up this model.
@907137:Only two hours from box to this point!

The decals were added later that night after the kids went to bed. The decals really dressed this little bird as a possible home built. There were Continental labels for the motor, fuel filler caps, a door outline, a storage hatch, and NO PUSH/LIFT HERE labels.

@907138:Classic looks...
@907121:from any angle...
@907139:Possible home-built?

The final weight of mine was 9.6 oz. which is slightly over the 9.5 oz. range specified on the box. I could easily get it under this weight by removing the receiver cover, or using a newer micro receiver.

!!CG and Throws
The battery compartment is basically under the C.G. and there is plenty of room fore and aft to balance the model. The wing is built with the spar on the balance point, so it is easy to check the C.G. before each flight.

I programmed the control throws in my radio, setting them to the recommended 1/2" in all directions.

!!What About Wing Assembly?
Did I forget to mention the wing assembly? That's because there is none other than tightening up the covering and bolting it on the fuselage.

!Flying

The maiden flight took place on a cool, breezy day after work in my front yard. Gusts earlier in the day had been in the 20mph range, but were now down to around 10mph. I did a quick range check and some taxi tests. With the fixed tail skid, it is not recommended to try and R.O.G. It can be done, but it takes some skill.

I am not the most coordinated guy when it comes to hand-launching models, but I couldn't wait to try it out. I throttled up the Lil' Rascal and gave it a running toss into the wind. It climbed out with authority and handled the breeze with no problem. The Lil' Rascal really cooks along and is much faster than other park flyers that I've seen.

After adjusting the trims and a quick stall test, I cruised around, getting a feel for it. Like most R/C pilots these days, I learned with an aileron trainer, so figuring out some of the rudder/elevator maneuvers took some practice.

It is very easy to keep it in a small area (my front yard is about 400' wide and 200' deep) and you can bank and yank it all day. If slowed down too much it can snap out of a turn, but all you have to do is get a little speed back up and pull out.

For landing, I started to reduce the throttle once on final and kept the speed up until touch down. I learned not to slow it down too much or it can stop flying, but the springy landing gear can take a beating. On the first landing, one of the clear plastic wheel plates popped of, but a few more drops of CA put it back in action. After any landing on anything but pavement, the Lil' Rascal usually ended up in a three point position (two wing tips and the tail), but it is a tough bird. I pile drove it from 20' after a botched snap roll and just picked it up and tossed it back in the air.

!!Aerobatics
On the subsequent days I proceeded to ring it out. The Lil' Rascal will loop from level flight, but they are prettier with a shallow dive leading into them. Rolls take some practice, and make sure not to put in full down when inverted or the roll will stop. Snap rolls are quick and it takes good timing to stop them upright. It prefers stall turns to the left, probably due to the p-factor of the relatively large propeller. Spins are wicked and the recovery is instant. Shooting touch and goes on the street is cool. The Lil' Rascal is simply a ball to fly. About the only thing lacking is the climb rate, which is not as good as I would like, but is not a big deal. Two friends of mine have added a third cell to their Lil' Rascals and have improved the climb rate. However, one has burned up the stock motor and the other uses full throttle <b>very</b> judiciously.

I have changed out the propeller to a APC electric 7x5, and this gave slightly better performance than the stock propeller. The gearbox is a bit on the noisy side, and after one flight I noticed the motor seemed loose. Upon closer inspection, one of the screws mating the gearbox to the motor was missing. These screws are Philips head and the way the gearbox is built it is hard to tighten them fully. I replaced them with some 2mm hex head screws and added some Lock-tite for good measure. Other than that, I have had no problems with the Lil' Rascal.

!!Run Time
The 1020mAh pack is overkill for this model. I have put in 10 to 12 minute flights and only had to add about 500mAh's back into the pack. This boils down to an average current of 3 Amps in flight. While there is a cooling inlet into the battery compartment, there is no outlet. However, at these current levels, the pack comes out just warm to the touch and it is not stressing the cells.

I would not recommend this model to a beginner, due to the "snappy" nature of the design. However, this is what can make this model a blast for a pilot with a couple of planes under their belt.

!Flight Video

+907141:I took the Lil' Rascal up to the Pontiac Miniature Aircraft Club fun fly over the weekend, and was able to shoot some video of it in action with Keith Shaw at the controls. Lots of fun aerobatics!

!Conclusion

Sig has hit the mark with the Lil' Rascal. This is one of the few ARF electrics that I've seen where you don't have to hop up the power system to enjoy the model. The stock power system is more than adequate, and as you can see on the video it is capable of just about any rudder/elevator maneuver. To me, the balsa construction is a big plus if you end up needing to repair it. While some may shy away from a rudder/elevator model, I look at it as a new challenge to learn some new tricks and relive the early days of radio control flight. Get yourself a Lil' Rascal and have a ball!

Otay, Spanky! (Sorry I couldn't resist!)

@907140:Here's my Lil' Rascal with my new park flyer.

jperch
Aug 13, 2004, 10:15 AM
Jim,

Well done on the article. I agree with most of what you said. I really like my lil'Rascal. However, in my case at least, I felt the power system was slightly lacking. I thought perhaps it was due to the fact I was using a 2s lipo pack instead of 7 cell NiMH. In addition, my unit came in at 8.8oz AUW. Don't get me wrong, it flew very well on the stock system. But, I am not used to having to actually push an airplane on launch. I usually just give it a slight toss to get me hand out of the way. I also could not really loop from level flight. It took a pretty good dive to get enough speed to keep it from falling out at the top.

Anyhow, I recently replaced my stock motor with a small CD rom motor from LensRC. I use the same 2s TP 730 lipoly pack as before. Now the motor draws 4.5 amps and generates about 9.5oz of thrust. Also, the AUW dropped from 8.8oz to 8.4. I did not intend to make the Lil'Rascal a huge powerhouse. But the extra power is comforting to have. I just wish I had added a little more down thrust as she climbs when you add power.

Thanks again for the great article.

Joe

Jim Young
Aug 13, 2004, 02:33 PM
Hi Joe,

Glad you liked the article. As I said in the article, the stock motor is not bad. I'm running the 2S 1020 Kokams and a gental toss get's in the air and it will loop from level flight. The climb rate is a bit lacking, and it takes a few circuits of the field to gain some altitude for spins.

I have tried one flight with a 3S pack and the power increase is significant, but the motor comes out hot.

One more note on the gearbox. Many complain about the noise, but the other night I had it out of the plane and I was fooling around with the gear mesh, this box runs very smooth and quiet. Once you put it back into the model, the balsa structure acts like a guitar box and the noise resonates through the fuselage structure. I guess that's the price you pay for having a repairable structure.

Spins are really cool with this model, you just need to keep some power on to make the rudder effective.

-Jim

jperch
Aug 13, 2004, 02:47 PM
I know what you mean. I used cells that were a bit lighter than yours but I still could not quite loop from level and a launch was a significant push. Just to give it that little bit of extra speed. But, now mine spins and snaps very well. Climb rate is also...spectacular. Anyhow, thanks again for the article. I look forward to others from you.

Joe

Doug Sipprell
Aug 17, 2004, 08:20 PM
Jim:

Good article, very complete, well documented with photo's, etc. I am enjoying my Lil Rascal immensely. However, I did make two major changes, one as a matter of personal preference, the other as a necessary performance upgrade. The performance upgrade was the APC 7x5E prop, originally suggested by Don "Bayou Boy". It definitely made for a better flying model, at least in the case of my plane. Secondly, I decided I could not really enjoy the noisy gearbox. Mess adjustments and other tweaks aside, I decided to go the route of a direct drive brushless motor, in this instance the AstroFlight 010. MAJOR change in personality and performance of the plane, and boy is it quiet! However, this is a big change to make. The plane is now a "pocket rocket", or a little racer. I use a 500 mAh 8 cell AAA NiMH pack, good for a solid 10-12 minute flight. Hope to try LiPolys later on, when I get a charger for same. What hasn't changed is the shear beauty or "cutenesss" of this model. It really looks and flys great. Sig has a winner here, all of your comments fully verified. I could not build it as nice as Sig has presented it to the RC public as an ARF.

Good luck with your Lil Rascal and thanks again for a great, informative review of this model.

RD

Jim Young
Aug 18, 2004, 05:43 AM
Doug,

I'm glad you liked the article. I always worry about giving a "glowing " review for a product for fear of appearing to be salesman for whoever, but in this case I really think that Sig did an excellent job of designing and producing this model.

The Lil' Rascal has become my traveling buddy and is in my car right now. I now have a plane that I can sneak out of work for a quick flight at lunch or after dinner in the front yard.

The gearbox is the one fly in the ointment, but my experience is that it is not the gearbox but the balsa construction. I have the same problem in my Little Extra and that is running an Astro 020 and a Superbox. The balsa fuselage sides resonate like you wouldn't believe, just like in the Lil' Rascal.

-Jim