I just completed my 4th ARF Nobler and felt like posting some text and photos. The Nobler was the first ".40 size" C/L ARF to hit the market around summer of 2002. Its features, benefits and short comings have been hashed and rehashed (in what some might consider nauseating detail) over the past 10 years. Therefore, I totally understand if the moderators decide to dump this post to save space on the server or wherever forum data is stored. Nevertheless, I feel everyone who assembles one or more of these kits usually has new and interesting experiences to share.
I started on Nobler # 4 in the winter of 2003 so I probably hold the endurance record for length of time to "build" an ARF. It was flown about 4 dozen times late last season with no color trim or decals. Final dry weight is now 49.5 ounces. The box says "ready to fly in 4 to 6 hours". It had been so long since I disassembled it to add the trim, that I forgot how it went back together! The reassembly process took several days!
This one is fully take apart and uses my favorite methods. A reinforced plywood bulkhead ("F-3"), 1/8" plywood plate and stock 1/4" dowel anchor the wing in front. Blind nuts are installed for two 4-40 bolts that screw in from the rear of the tank area. These are optional. I have flown without them, but they do provide an added measure of security. The rear of the wing attaches with two 6-32 bolts and threaded inserts that are screwed and epoxied into maple blocks. The blocks are epoxied to the stock plywood crutch the ARF fuselage is built around. The kit comes with a "semi-take apart" wing and fuselage. Its mainly for alignment purposes when setting the wing up for gluing. I would never depend on it to hold the model together in flight.
The stab is held in place with two 4-40 bolts and blind nuts in a plywood plate between the fuselage sides. The rudder, fin and part of the rear fuselage form a plug that attaches with one 4-40 bolt. Since I stooge launch 99% of the time, I bent my own tail gear from 1/16" music wire. It is permanently epoxied in place between the rudder and tail post. A line clip serves as the hookup for the stooge release pin and a soldered washer isolates it from the tail wheel. I could loose the tail wheel but would not loose the clip.
The flaps and elevators attach with long lengths of thin music wire and are removable. I made a shallow groove between the hinge halves on the flap LE and stab TE and Monokoted over the groove to hide the wires. A bend in the wire for the outboard flap traps it at the nylon hinge nearest the fuselage, so I don't have to tape it. The wire for the inboard flap has a more complex double bend at one end that fits into a groove in the tip of the flap. The elevators attach with a single wire similar to the inboard flap. A double bend at one end fits in a groove on the inboard stabilizer tip. There is no interference between the wire and elevator horn. 3M clear vinyl tape is normally used to hold these 2 wires in place, but I could probably get away without it. Centrifugal force, combined with a snug fit, should be enough.
The stock hinges are not nylon (or its a low quality nylon) and are prone to breaking. All were replaced with Sig or Du-Bro nylon hinges dyed blue with Rite Dye. There is very little gap along the hinge line. This somewhat limits the control travel, but I wanted to see how narrow I could make the gap and get away with it. I don't like the idea of taping the hinge line. I've checked out other models with taped hinge lines. The controls felt a little stiff. I was told it needs to be redone periodically. I may give it a try sometime, but for now I'll pass. If I planned to use tape, I'd opt for a wider hinge line gap.
Of the 4 ARF Noblers I did, this is the only one that uses the stock bell crank. I've read some negative comments about It, but it "looks" fine to me. I've seen a photo of one that wore out in a short time. After several dozen flights I'm not seeing any wear or slop in mine. I installed my own lead outs (Sig .027" cable) and bushed them at the bellcrank holes with brass tubing. The ends are wrapped with copper wire and epoxied. I don't use crimps. I used the stock metric bolt, but replaced the gummy nut with a blind nut. This creates the option of loosening the bellcrank and repositioning the pushrod to a different hole to change control sensitivity. I can also replace the bellcrank if the need ever arises. The bell crank to flap pushrod is 3/32" music wire with an "L" bend at the bellcrank that is trapped in place by the plywood floor. A "Z" bend at the opposite end attaches it to the flap horn.
The long pushrod is a carbon fiber tube with titanium ends glued in place with slow cure JB Weld, then wrapped with 1/2A flying line soaked in epoxy. A gold Sullivan 4-40 clevis screws onto each end with a jam nut only at the flap end. Its my "theory" (feel free to debunk it) that one end of the 2-clevis rod should be free to rotate. This prevents the development of alignment issues that might occur as the controls travel through their range of motion. A jam nut on both ends limits rotation. If alignment issues developed, that would put a strain (torque) on the clevis pin and yoke, possibly causing a dreaded "clevis failure". I've been told a jam nut prevents the clevis from pulling off the end of the threaded rod. It hasn't happened to me yet.
Both control horns are removable. They could be used in other models without destroying this one. The flap horn is a Tom Dixon unit with steel upright (his horns are "clevis friendly"). The elevator horn is stock with a brass upright. I soaked silver solder into the joint between the wire and vertical part. I did not bush the clevis hole in the elevator horn, but did in the steel flap horn (with a very short length of tiny brass tubing). Since I have complete access to all control system components, I can check and replace each clevis about every 100 flights (or every 500 if I'm feeling lucky)! When doing so I have not noticed much wear on the pin, or any other issues. These are tough little parts!
Nobler #4 uses the LA .46 (currently my favorite stunt engine) as does Nobler #2. A rear exhaust lite case Stalker .40 was used in Noblers #1 and #3. The last time I flew Nobler # 4 (probably October 2011) I used an old Tornado 10 X 6 nylon 3 blade prop. It looks wicked and works surprisingly well (Nobler #2 is flying with a higher time LA .46 and 11 X 5 Zinger prop). The tank in all 4 Noblers is a 4.5 oz. Brodak medium wedge. This is the only commercially available metal tank I could find (ten years ago) that fit inside the ARF's narrow fuselage. Run time varies with conditions, but its enough for the pattern with a few laps to spare.
The engine mounts on 1/8" steel pads and the motor mounts are recessed 1/8 inch in the tank compartment to allow height adjustments. I removed most of the front former (F-1) and added a horizontal former that traps various shims to hold the tank in place. One shim is 1/32" plywood and 3 are 1/16" balsa. All are Monokoted to prevent fuel soaking. One shim is 1/4" styrene foam covered with tape. Their positions can be shuffled to adjust tank height as needed to equalize the engine run upright and inverted.
I use a Sig GP003 plug and blend Sig 50/50 Klotz & Castor fuel to get 7.5% nitro. In the heat of mid summer I sometimes combine all Castor with 50/50 fuel to get a Castor rich blend and may boost the nitro to 8.5%. I don't go to 10% because it takes seconds off the run time, which is already tight. In any case, I don't need the power of 10% fuel and sometimes use only 5% in the fall and spring. Initial flights were with an OS model 843 muffler. It was quiet but too heavy. I quickly switched to a tongue muffler with Du-Bro pressure fitting. The Hayes fuel filter is my favorite. I sometimes buy them in bulk with extra gaskets and screens.
Lines are .015" diameter cable 61 to 62 feet long eyelet to eyelet (Tom Morris Lines from Control Line Central). I sold all my handles with cable leads and now use the Brodak hard point adjustable handle (small for the Noblers and large for the Score). I use a Tru-Turn 1.75" diameter spinner with a Tru-Turn coupling nut, washer and bolt. These parts cost about 1/3 as much as the kit, but its the best spinner I ever used. The prop stays tight for many flights and (baring a crash) they should last forever.
I left most of the original Sapphire blue Monokote covering in place, but did remove some in the white and yellow trim areas at the wing leading edge. That reduced the bubbles and saved a few grams. The entire inside of the fuselage back to the wing trailing edge is covered with Monokote. Normally its easier to paint this area, but I wanted to see how far I could go with film. I found that where I can get a hot trim tool to go, I can Monokote it. The white, yellow and gray trim and AMA numbers are all Monokote. The decals are Mylar and vinyl stick-ons. Most won't last, but they are easily replaced.
Some Lustrekote paint was sprayed into the rear fuselage at the wing trailing edge, in the stab area, inside the tail plug and any place I could not reach with the trim tool. If you make it take apart, oil residue will eventually collect on the inside. I added lots of paint to the cowl, which comes nearly devoid of resin or paint on the inside. If not completely fuel proof it will quickly deteriorate.
Only 12 photos are attached. I have many more, but don't want to bog down the forum. If there is interest I can post more (or email me directly: stuntcl@windstream.net). This will probably be the last ARF Nobler I do. At this point I'm pretty much "Noblered out", but have not completely ruled out doing another. The design is "take apart friendly" (as are many others). If you are interested in having a take apart stunter, the ARF Nobler is a good place to start.
Whether you completely rework it or nail it together "stock", its still a bargain at the current price of around $120 or less. Even with all the substituted hardware, engine and accoutrements needed to complete it, you would be hard pressed to put more than $300 into one of these (unless you opted for one of the more expensive engines and/or stripped off all the covering and finished it with silkspan and dope). Regards, EWP
Topic: Last ARF Nobler (Read 2757 times)