A REVIEW OF THE 3D HOBBY SHOP Extra 300 SHP
by Hal Marshall
SPECIFICATIONS
PLANE: Extra 300 SHP
MANUFACTURER & DISTRIBUTOR: Extreme Precision \ 3D Hobby Shop
TYPE: Aerobatic 3D
FOR: Intermediate to advanced
WINGSPAN: 47.25"
WING AREA: 646 sq. inches
WEIGHT: 37 – 41 ounces
LENGTH: 44"
RADIO: Spektrum DX7 with AR6000 receiver
POWER SYSTEM: Hacker 30/16M, Castle Creations 35 ESC, EVO 2170 3s Battery, APC 12x6
FLIGHT DURATION: 8 – 10 minutes
MINIMAL FLYING AREA: Baseball field
COMPONENTS NEEDED TO COMPLETE: 4 HiTec 65HB Servos, 2 6" servo extensions, 2 4" servo extensions, CA, Epoxy and typical building tools and related items.
PRICE: $149.00
SUMMARY
If you’re looking for a ‘sized right’ 3D capable performer, with curb appeal, the 300SHP is just the plane. Ease of assembly, removable wings, and top-notch performance makes this the perfect plane for that quick trip to the field during lunch or lazy afternoons. With a wide CG range and performance from mild to wild, the 300SHP is sure to please the aspiring 3D pilot as well as the seasoned 3D vet.
INTRODUCTION
In recent years, the selection of 3D capable electric sport aircraft has increased immensely, which can make selecting quality aircraft a daunting task. One of my favorite vendors is internet-based 3D Hobby Shop. They have a great selection, pricing within my budget, the aircraft are of very good quality and their service is outstanding as well. The 300SHP is my second aircraft from 3DHS, the first being the 47" Katana, a very satisfying aircraft. There is also a 300 SHP thread on rcgroups.com where you can get your questions answered by the planes’ designer and 3DHS representatives. The 300 SHP is designed by Scott Stoops. Scott is an ATP rated airline pilot who competes in full scale International Aerobatics with his Yak-55, and is author of Mastering Radio Controlled Flight. He currently designs, tests and reviews kits. The 300 SHP features Stoops designed light wing loading and thin airfoil section making it a very capable plane in all 3D maneuvers.
PACKAGING, CONSTRUCTION, AND SETUP
All 3DHS planes arrive triple-boxed. Three heavy duty boxes at that! All the pieces are wrapped in plastic as well, with the ends taped instead of stapled. A helpful touch if you’ve ever hooked a staple on covering removing it from the bag. The kit comes completes with all the necessary hardware, which is of good quality, needed to complete control linkages, landing gear, etc.. Two nice sheets of decals are also included. The construction manual is spiral bound and well illustrated. Also included is an addendum describing some slight modifications that have been incorporated into the plane since it first release, such as the spring loaded canopy. The manual also offers helpful construction tips covering such areas as hinge sealing as well as how to fly some of the more common 3D maneuvers.
PACKAGING, CONSTRUCTION, AND SETUP continued;
A quick inventory/inspection showed all the pieces were present and the covering in good condition with minimal wrinkles. The kit is built up balsa and ply, with carbon wing tube and gear struts. The manual also includes an addendum describing some slight modifications that have been incorporated into the plane since it first release. My first step was to open the areas for servos, wing tubes, vents and so forth, then seal the edges. I also applied a thinned mix of 30-minute epoxy and alcohol, painted on the gear, firewall and battery tray area. From here I moved on to wing assembly, which was pretty straightforward. The servos dropped in without problem and a bit of 30-minute epoxy seated the control horns firmly. After curing the hinges were gap sealed using Hanger 9 transparent Ultracote. The installation of the horizontal stab was a bit more difficult, as it wasn’t aligning with the wing tube correctly. This took a bit of sanding and shimming to correct. Since it uses a joiner wire to connect the elevators, they required some adjustment as well to properly line up with the stab. A bit of care had to be used in bending them to the correct position for a level fit. In the end I couldn’t get both elevators exactly flush with the stab, off by about 1/16th. During trim I split the difference between them to 1/32, which is certainly acceptable on this type and size plane. Some care also needs to be used when attaching the control horn to the elevator, as too much pressure inserting it might force it through the other side. Before hooking up the linkage I gap sealed the elevator with 3M Blendurm tape.
Next step was installation of the rudder and tail wheel. Again this was pretty straightforward. (The kit also includes hardware and mounting area for a pull-pull system if that method is desired. For this build I positioned the servo at the rear). The only additional work was a bit of sanding on the bottom of the rudder and aircraft, where the wire for the tail wheel spans. This was needed to get the wire on the rudder flush with the metal bracket securing it to the airplane. Instead of using the supplied wheel collar to secure the wheel, I used the bottom portion of a Dubro easy connector, which fit the wire perfectly, secured with a slight dab of 5-minute epoxy. Centering the servos and installing the linkage completed this portion.
The motor installation was seamless. The Hacker 30/16M bolted directly to the preinstalled blind nuts, and required no standoffs. Per 3DHS, the blind nut arrangement is designed for the Torque series of motors, so choice of another engine, such as an e-flite Power series, would require some drilling and modification to the firewall, though it’s not a show stopper. Hacker and Torque happen to have the same pattern. There is so much room on the engine mount and battery compartment that the ESC can be mounted just about anywhere. The location I choose gave me the perfect place based on the length of the ESC connectors. It’s out of the way and everything is reachable. Next was completion of gear assembly and installation of the struts, both without issue. The plane comes with wheel pants; I’m just not a wheel pants guy so they weren’t installed. Using the method of marking the cowl screw locations with folded paper, the cowl installation was pretty straight forward, with a nice secure fit.
For installation of the receiver, I added a small ply tray to the back end of the battery tray. This positioned the receiver where it’s centralized and within comfortable reach of the wiring. Fitting the wings and adding decals rounded out the assembly. The CG should be 3.25 – 3.75 inches from the wing root. I used Scott’s recommendation as a starting point, and balanced it at 3.5. Another nice feature… the battery tray is huge! The best I’ve seen in an electric. Regardless of the battery pack used, you can find a wide range of CG‘s on this tray. No more tight-fisted cramped quarters here! Overall, the whole process took 3 evenings. This would have been shorter if not for the trouble with horizontal stab alignment. Still not bad, considering I’m a pretty slow builder. The following radio settings are used as a starting point, again these are Scott’s recommendations;
Low Rate
Aileron 15 degrees .75" 30% Expo
Elevator 13 degrees 1.25" 30% Expo
Rudder 45 degrees 3.5" 75% Expo
High Rate
Aileron 28 degrees 1.25" 75% Expo
Elevator 45 degrees 3" 85% Expo
Rudder 45 degrees 3.5" 75% Expo
FLIGHT REPORT
Weather for the maiden was clear sky, a crosswind steady at 5 gusting to a bit more. This flight was flown on low rates. Takeoff was uneventful and the 300 climbed out effortlessly to vertical. My first pass to check trim was surprising, it didn’t need any! Check of CG showed it to be slightly nose heavy, which is fine, lots of room to move the battery around. Stalls are very clean with minimal recovery effort. Knife-edge tucked to the gear, but not much. An easy mix will take care of that. Since I’m not good at hovering, an attempt 3 mistakes high leads me to think it would perform it without problem, even at low rates. It did not feel sloppy at all. The plane really shined in Harrier. Has a nice locked in feel with very little to no wing rock. Rolls were very smooth. A few more runs around the pattern and it was time to land. Even with a bit of crosswind I felt very comfortable with it. It slows down nicely and with a bit of throttle modulation it does a nice almost harrier landing. Did not work with inverted attitudes except to check CG. Throughout the flight, the plane felt solid. At no point did it feel squirrelly or like it was going to get away from me. I can’t imagine how this plane will perform on high rates!
CONCLUSION
Good size, easy to build, outstanding performance and outstanding customer service. What’s not to like? Everything about this plane is as advertised. While I’m certainly no 3D or Sport plane Pro, I can’t think of anything about it I would change. For my money, I believe the 300 SHP is tough to beat in costs and quality of 3D planes in this scale. So if you’re looking for a quick-build, easy to transport and certainly fun to fly 3D electric, give the 3D Hobby Shop 300 SHP a go!
LINKS
3D Hobby Shop 300 SHP http://www.3dhobbyshop.com/detail.aspx?ID=1996
RCGroups Review http://www.rcgroups.com/forums/showthread.php?t=646127
Hacker Motors http://www.hackerbrushless.com/
Castle Creations http://www.castlecreations.com/
Spektrum Products http://www.spektrumrc.com/
