Well, a very large box arrived today, Tuesday 20th June!!! Be aware that the 3m models are not shipped in crappy cardboard kit boxes, oh no!!
They arrive in full-on wooden crates!!! The only downside is their weight - mine weigh 47kg with the pallets the shipping company had attached it to!!!
Anyway, to the building....
The very first task is to protect the fuselage and the quickest way to do this is to fit the gear and this is easily done. Simply mark the hole positions as per the picture in the manual and drill. With the holes in the positions shown, you may need to remove some of the fuselage skin to the front of the u/c leg slots - this is easily done with a small file. I ended up removing about 10mm. You could minimise this by moving the u/c mounting holes slightly forward - maybe a few mm but don't go too far. It is better to remove a little of the fuselage skin that weaken the u/c legs by drilling too near the front edges.
Once you have drilled one leg BE SURE YOU DO NOT DRILL TWO LEFT OR RIGHT LEGS!
The legs are simply bolted in place through the pre-cut holes in the underside of the fuselage using the supplied 6mm bolts. Be sure to apply some loctite to these bolts to avoid them backing out with vibration.
Start by drilling the two 6mm holes in the u/c legs where indicated by the 'dimples'. Next drill an 8mm hole in the outside of the spat where the 'dimple' is and another 8mm directly opposite this. Take the plywood U shaped piece and a 6mm captive nut. Open up the hole in the U shaped piece so that the captive nut will push through and protrude by about 1mm - the teeth of the captive nut will just bite into the ply. Mix up a thick batch of epoxy/microballons and glue the captive nut in place. When dry, epoxy the U shaped piece on the inside of the spat making sure it is in line with the carbon leg. Hold everything in place with a spare short 6mm bolt whilst it dries. Once dry, drill a 3mm hole through the u/c leg, spat and U shape ply piece about 20-25mm above the axle bolt. Remove the spat and open the hole in the spat and plywood only so the 3mm captive nut can be glued in place - this will hold the spat in place and stop it rotating.
Fitting the wheels works great if you use the Dubro 5" wheels. Push the bolt through the outside 8mm hole and place one of the supplied wheel collars on the bolt followed by three of the washers. Place the wheel on the bolt followed by a washer and another wheel collar before screwing the bolt into the captive nut. When the bolt is tightened right up, you'll come to the end of the thread, you should find that the spacers allow for the wheel to spin freely but only move side to side by 1-2mm. Finally, fit a washer and the 6mm locknut and you're done - your 260 should now be sitting proudly on its "feet"!
Start by taping the lower cowl half in position aligning any paintwork as best as possible. When happy, use a 3mm drill bit and drill 3 equally spaced bolt holes through the cowl and fuselage. My holes were 7mm from the back edge of the cowling. Temporarily fit the captive nuts in place to securely hold the cowl. Now fit the upper cowl half and tape exactly in place.
Drill the holes for the upper/lower cowl joining bolts. I drilled my holes 6mm up from the cowl joint line - this worked out nicely. My rearmost cowl joining bolt was 25mm from the back edge of the cowl and the rest of the bolts were spaced 11.5cm apart.
You may find that some of holes fall in awkward places i.e the captive nuts don't sit flush because of the step between the composite foam and the fibreglass dome. This happened to me on the two top cowl mounting bolts. A very simple fix is to just dremel away the little bit of foam and the captive nuts fit perfectly OK. You may also find that the top bolt of the 3 lower half cowl bolts is in a position that means the u/c former does not allow the captive nut to fit. You have 2 options here. Firstly, move this top bolt forward by about 10mm. Alternatively, if you have already drilled the hole or you want your bolts to be in line, you can simply cut off the top 10-12mm of the u/c former to allow the captive nut to fit - this was what I did.
You will also need to drill a 10mm hole in the fuselage engine dome to allow the rearmost cowl joining captive nut to fit into otherwise the cowl will not sit flush.
Once everything looks good, coat all the bolts in some grease then apply a good blob of aeropoxy on the back of the captive nuts and bolt everything back in place to dry overnight. In the morning the grease on the bolts should allow their easy removal even if there was some wayward glue. You won't be able to glue the captive nuts in place for the 2 rearmost cowl joining bolts but these can be don afterwards with the cowl off of the model. Simply bolt the two halves together and the glue the last 4 bolts in place. Oh, and did I mention it was a BIG cowl!!!
Start by locating all the parts to build the rudder tray. Press fit everything together and secure with cyano. Cut 8 servo bearing strips from the supplied lengths of 3mm ply but don't glue them on yet! Check that your servo fits in the servo bay recesses. You may find that the slightly larger servos such as the 8611 rather than the 8411 won't fit without opening up the bay slightly. Once done, glue the ply rails in place. Doing it in this order saves the hassle of having to open up the slots with the ply rails glued in place! Finally, run some epoxy/microballon mix along all the joints for added strength.
Next, install the servos as centrally and in-line as you can and drill the holes for the servo screws. Screw the servos in place. At this point I had servo leads dangling everywhere so I chose to tidy them up. I attached 4 60cm extension leads and secured them with heat shrink tubing over the connectors. So as to ensure all the servo leads ended in the same place despite the staggered position of the servos I tie wrapped and spiral wrapped the leads so that the extension leads all started from the front of the rudder tray.
The leads were then spiral wrapped and secured to the mounting former ready for installation.
Next up was the ganging of all the servos.
First thing I did was to elongate the slots in the elevator false balsa leading edges. This was to allow the maximum amount of movement for 3D deflections by giving more space for the phenolic horns. This cannot be done at the factory as the milling machine would break the balsa if it slotted very close to the edges. A small file and about 10mins did both sides and allowed for loads of movement!
To hinge the elevators simply align the phenolic hinges and slide the 4mm aluminium tube through them. Do not push to hard as you may damage the phenolic hinge arms or bend the ali tube. Once in place, get one end of the tube about 0.5mm from being flush with the stab and mark the tube at the other end where it exits. Slide the tube back out a little and cut the tube about 2mm inside the mark. Slide the tube back in so that it is about 0.5mm 'inside' the stab. This will allow you to place some good quality clear tape over the ends of the holes to retain the tube with it pressing against the tape.