Rudy, can you dig up the ImpAct article or plans? The system looks good to me. I would not be at all opposed to putting a plywood platform on the fuselage and putting 4 bolts through it into the stab. The fin would have to bolt to the stab at the front, and perhaps an aluminum tube spar/socket at the rudderpost, with another screw (forward) to anchor that. Removeable hinge pins is the way to go, IMO.

Let us know how that Sullivan springy thingy works for you, 'cause I think it might be good for a couple of flights...    I wouldn't do it!  Servos are not as quick as our "flickadawrist", so the control loads are much softer for RC. Well, you wanted our opinions. I would use...a ball link and a brand new elastic lock nut each time I reassembled the model. They're cheap in a box of 100...and real cheap insurance.  Steve

Hi Steve and Matt,

Thanks for your input.

Steve,

Good suggestion RE: the Impact. I have looked at the plans. If I was starting from scratch that is not a bad way to go. I like Wayne Ulury's KIS method he uses on the 1/3 Laser. I have owned three of them and I really like his design. I am able to hold/remove the whole tail, both stab/EL and vertical fin/RD, from my 1/3 Laser with only three 4-40 bolts. Wooden dowels take most of the stress.

Of course the best way is the method we use in almost all of our RC planes, from our small 11 lb. planes to our 40+ lb. planes. That is sliding the stabs on to a CF tube, just like the wings. If I was not so lazy I would make a CLPA plane just like one of my modern, beautiful RC planes, using CF tubing on both the wings and the stab. ..... But I will leave that to you, Bob Hunt, and other building experts. :-)

The Score is already close to a take apart tail. It can easily be done by making the bottom brace removeable with two more screws. This would then require a total of 12 screws to remove the tail. Which really means 24 screws are needed because at least 12 will get lost in the grass during the "screwing" process!  ..... I just wanted to see if anyone had found a way to make it more "KIS", with less screwing going on.

RE: the springy things, I have never used them on my 30+ lb. planes, but I have used them on my 11 lb. plane with a Saito 1.80 for power. There is no stress on the spring part, it only captures the ball link.

But, with that said, you do make a good point about getting 100 nuts and using a new one each time with the tried and true bolted ball link system that I have been using, trouble free, for >30 years. I think I will take your good advice of caution and try it out on my ARF Flight Streak "test bed" 1st. 

RE: our servo speed Vs hand speed. My new digital 200 oz. servos on 6 Volts are very very fast, I don't think our hands could beat them moving the EL to 15 degrees. And I can't imagine the CL forces being any higher than the ones on my Elevator while doing a blender, or a high speed snap roll with a 30+ lb. plane. We also pull pretty hard and fast at pylon #1 at over 150 mph with our pylon racers. .... But I could be wrong, it has happened before. 

Matt,

Your right about the wing being removeable. It uses the basic method used on small RC planes that works very well for our CL size planes. The tail is not made to be removeable, but it is close as is. (please see my note to Steve above).

I want to have it take apart so that it fits into my "Sport tube" for shipping by UPS or to use on the airlines.

Thanks again for your inputs.

Regards,   

I took many photos of mine when doing the "mods" to make it fully take-apart, but almost none of the tail. I plan to tear it down for a check up and cleaning in a few weeks and will take some then.

On the Score, the easiest way to make the tail take-apart is to NOT glue either hatch on and to make the elevators and elevator horn removable. I used 1/4 scale pinned and barreled nylon hinges (Sig XX hinges). They are probably overkill and added to the weight. Standard size Du-Bro or Goldberg hinges should be OK.

Use a continuous wire for each elevator (largest diameter that will pass through the hinge hole). Carefully cut neat recesses (about 1/2 inch long) in the elevator tips to receive L-bends in the wires. If desired, you can make a 2nd L-bend 1/4 to 1/2" long that presses into the wood. I did, but it's probably not needed. Bend and trim the wires accordingly. I use 3M Decorative clear vinyl tape to hold the wires in place. Fold a corner of the tape over on itself to make a pull tab for easier removal. Use new tape every time it's reassembled.

A snug fitting wire helps align the hinges during gluing. I Dremel the end of the wire to a point. That makes it easier to pass through the hinge barrels (and to poke myself with-keep it away from your eyes!). Thirty minute epoxy is the best hinge glue. Remove excess with lacquer thinner. Once the hinges are in place, oil the wires and run them through the barrels to remove any glue. I do it in stages and "baby" the assemblies until the glue sets up. If the end result is stiffer than you like, replace the original "set up" wire with the next smaller diameter. Now the control surface will be "really free". But avoid a "sloppy loose" surface. It could vibrate and cause problems.

For the horn, I find a piece of aluminum tubing that will accept the horn wire, then open up the holes in the elevators to accept the tubing. Soak the holes with thinned 30 minute epoxy, rough up the tubes with 320 grit paper and glue them in. Break the fuzy end off a Q-tip, soak it in thinner and use it to dig out any glue that may have creaped into the tubes. When cured, open up the tubes slightly with a rat tail file, so the horn makes a snug fit, but can be installed and removed without sticking. Now the horn holes in the elevator are fully fuel proofed and will not "egg out" over time.

I used a Dave Brown fiberglass pushrod with 3/32" wire and "L" bends at the end. It's held in place by stock internal fuselage structure, together with a balsa bumper at the flap horn. A Sullivan Gold clevis could be used, but I have "clevis phobia"!

I use the stock metric bolts to hold the stab in, but add a drop of temporary thread lock. These are the only 2 take-apart bolts that are not easily checked for tightness at the field. I rub epoxy or Sigment into the holes where wood screws for the hatches thread in, otherwise they will get fuel soaked and not hold the screws. 

Two problems I had with my stab: I perceived a negative incidence in the stab saddle (actually a fuselage issue) and spent time with a Dremel Tool, reshaping the front of the saddle to raise the stab leading edge. Another problem involved the dowels in the stab for the mount bolts. One was soft and crushed when the bolt was tightened. I found a carbon fiber rod with the smallest ID that would accept the bolts, then opened up the stab holes to accept the rod. I cut 2 short lengths and epoxied them in. The result is very strong hard point pillars that will not crush. I used the same method to reinforce the motor mount holes in an ARF Flite Streak.

If I were building from a kit or scratch and wanted a take-apart stab, I'd do it in a very different way (probably the "Impact Way"). But I wanted to keep the kit's take-apart features as stock as possible and just make them stronger in certain areas. Regards, EWP
     

Well Rudy, now you've shamed me into doing a video of my Score like I promised a week or so ago. Tomorrow in the daylight I will do a Flip Video of the tail removal. It uses the same two stock mounting bolts. All I did was make the hatch opening longer towards the rear to allow the stab/elev to slide out with the elev drooped about 45 degrees after the pushrod bolt is removed from the horn. Very simple and no sign of problems after maybe 200 flights. I also added an alum plate on the bottom of the fuse-wing joint at the front to tie the parts together and provide a tension path from nose to tail along the bottom of the fuse. Otherwise it relies on the shallow top fuselage section to carry ALL the tension and torsion load from engine to tail. One picture is worth at least a thousand words here. I can email or post to YouTube the videos and stills this amazing little camera produces.

I finally disassembled my 5 pound Score for a late summer overall and took more photos of the components. Here are 12 of the tail area. As stated in a previous post, if building from a kit or scratch I'd use a different method (tail plug vs. hatches-see gallery photos of the ARF Nobler). I didn't see anything terribly wrong with the basic design of the Score's tail so my goal was to add modifications, rather than cut up or replace the stock kit parts. Pictures of other components might appear in later postings. These are the changes I made at the tail end:

1) The hard points in the stab where the anchor bolts go were reinforced with pillars cut from a CF tube. The ID is just large enough for the bolts to pass through. Stock holes in the stab were bored out so the tubes made a snug fit. They were glued in place with 30 minute epoxy. One of the stock hardpoints was too soft and crushed when the bolt was tightened, so this mod was needed. The tubes are not flush with the top of the stab. They extend about 1/8 inch beyond the top and contact the plywood platform that holds the blind nuts. They support the load when the bolts are tightened, so the stab is not crushed into the saddle of the fuselage. The white trapezoid piece in between the CF posts was an attempt to add more torque resistance to the stab in the yaw axis. It's not needed and did not work out as intended. I'd remove it, but it's easier to leave alone! The stab bolts are coated with a medium/temporary grade of thread lock, which keeps them from loosening during flights. They are not easily checked for tightness at the field, so thread lock is a good idea here.

2) I perceived a lot of negative incidence in the stab (leading edge cocked down), so I ground out the upper fuselage saddle until it "looked about right" (see the gap below the stab LE). The plane tracks OK, but so do stock Scores I've seen (and flown), where no change in stab incidence was made. If the stab is removable and you suspect an incidence problem, it could be tweaked after the model is flown.

3) I fuel proofed the inner fuselage at the tail by bringing the trim colors around to the inside with Monokote. Fuel proof paint or thinned epoxy would likely be easier. Fuel residue does get in this area. Lately I've become a Monokote fanatic and try to do impractical things with it. By the way, approx. 95% of the seams and trim colors have been sealed with straight or curved lengths of clear Monokote. The few places that were not are developing issues and will get nailed down with clear Monokote during this overall.

4) The hatches are covered on the inside with clear Monokote. The outboard hatch is grooved to clear the elevator pushrod. I used a Dave Brown fiberglass pushrod with 3/32 inch music wire ends from the flap to elevator horn. The stock formers (plus a balsa bumper at the flap end) hold the rod in place. The rod is heavy (24 grams), but does not flex at all and is very strong.

5) I'm using the stock elevator horn, bored out to make a snug fit with the 3/32 inch rod end. The horn looks like brass, so I did not add a bushing. There is no evidence of it getting "egged out" after approx. 100 flights. I'm using the center hole which gives a lot of travel, but I like it. I also set up the elevators to use a clevis friendly Tom Dixon horn. Each horn hole in the elevators is lined with aluminum tubing and soaked with thinned epoxy for fuel proofing. I made up a CF pushrod from Central Hobbies. It weights only 13 grams, complete with titanium ends, Sullivan clevises, JB Weld, Dacron line exterior wrap and epoxy soaking. I have "clevis phobia" and will probably never use it, at least not on something this heavy. With that thought in mind, I decided to fill the extra horn holes in the elevators with silicone. The empty holes do fill with oil during flying sessions.

6) Instead of the stock tab style hinges, I used Sig XX pinned and barreled nylon hinges (3 per elevator). A continuous wire holds each elevator in place. The wires lock into a recess at the stab tips and are held in place with 3M clear decorative vinyl tape. When peeled off, it does not take the covering with it. I use new tape every time these parts are reassembled. Folding the tape over on itself at a corner creates a pull-tab making it easier to remove. The recesses are fuel proofed with epoxy or Monokote. All Hinge pockets are dressed up with small pieces of Monokote and "flooded" with 30 minute epoxy for both strength and fuel proofing. The flap and elevator hinge lines are a "magnet" for fuel residue. I did not "peg" the hinges with toothpicks, but did precoat the pockets and flooded them with epoxy when installing the hinges. This is done in stages, not all at once. Lacquer thinner and TLC are used to wash excess glue out of the hinge barrels. The controls are very free with no binding through about 50 degrees of travel.

7) I used the stock tail wheel, but bent a new gear from approx. 5/64 inch music wire. I used 2 metal clips to anchor it to the fuselage instead of one nylon clip. The screw holes are soaked with epoxy. A short piece of brass tubing (flanged eyelet) is soldered on the outboard side of the wire. This acts as a bushing for the wheel, but more importantly locks in the line connector I use for a stooge anchor. The wheel is held on by a collar and set screw, but if it comes loose during a launch the line connector will stay put.

8) A removable and adjustable rudder was hinged to the fin via the wire and tubing method. I had to peel away some covering from the fin and replace it with Monokote. The aluminum tubes are glued in place with CA then reinforced with epoxy and strips of silk or 1/2 oz. fiberglass cloth. The stock trim scheme was carried over to the rudder with Monokote. Colors are a close match except for the red which is a shade or 2 off. Small nylon horns, a 2-56 threaded rod and a nylon clevis hold the rudder to the desired offset ( between 1/8 and 3/16 inch). I added the rudder after reading reports of a Score chasing it's pilot during an attempted reverse wingover! I have not yet flown it without the rudder.

The heavy duty hinges, hinge wires and removable rudder added tail weight, which necessitated more nose weight. I'm reluctant to remove the rudder, as it creates a warm and fuzzy feeling during the reverse wing over, vertical and overhead maneuvers. With some thought and effort I could probably shave an ounce off the tail, while still retaining it's current features and strength.  Regards, EWP