| Engine Installation:
On the DL-50, all screws used to attach the standoffs, muffler, and
propeller are 5mm (with a .8 thread pitch).
I used a set of the new DL supplied aluminum standoffs. If you substitute
different length 5mm bolts, please note that the DL standoffs are not
threaded throughout. There is about 18mm of threads on each end.
I created a template. Be sure standoffs are bolted onto engine securely
(there is some play so try to get them centered). Lay the mounted engine on the
paper and trace around the standoffs (so you can find and mark their
centers with cross-hairs). I usually draw on larger holes (that stay behind on the surface as a guide) than I drill
and just visually keep all the hole centers the same. Draw 1/4" (6.5mm) holes
on the template and cut out (I used a paper hole punch). Carefully hold engine and place template on back of engine/standoffs and verify the holes line up perfectly.
On template, draw long horizontal and vertical intersecting lines half-way in-between both sets of holes.
Tape on template (aligning with the pre-drawn thrust lines) and mark 1/4"
holes with fine Sharpie. Take off template and hold up engine one last time
to verify everything is lined up before drilling your holes (the ole'
measure 4 times ... drill once :-)
Drill 3/32" pilot holes (directly in the middle of the 1/4" marked
holes) and then finally drill the 13/64" holes.
Drill perpendicular to front of firewall.
Directly behind carb. (in center of thrust lines) drilled 7/8" hole through firewall so carb.
can breathe (as recommended by DL).
Properly gap supplied spark-plug and install per. DL's instructions. |
| Engine Mounting Notes:
First, just looking at the engine, you will observe that the large back main carb. air hole is directly behind the crank-shaft (and they have the same centers).
When you attach the DL supplied aluminum
standoffs to the engine, two invisible diagonal lines drawn between
all 4 near the back would also intersect
at that same point.
The standoffs are
68mm (2-11/16") long. The measurement from the back of the
standoffs to the front prop. hub is 6-11/16" (GP's pick, the Fuji-43ei comes in at 6-3/4").
Should work fine.
|
|
Attached (flipped-over) blue HiTec aluminum servo arm with 2-56 hardware (2-56x5/16" cap head screw and nylon insert lock nut) and 4-40x1/4" cap head screw (with lock washer) to engine's throttle arm to extend (this procedure adapted from this website). Drill 2-56 hole with 3/32" drill bit.
Installed throttle servo (in existing first back slot) with a 5 hole servo arm. Drilled 13/64" pushrod hole in firewall and again behind through middle of tank bracing ply (be sure pushrod will barely clear tank ... see next picture). Installed nylon semi-flexable push-rods with 2-56 ball-links on both ends (in outer arm holes). Replaced normal nuts supplied with ball-links with nylon-insert nuts to lock. Installed plywood brace (with a proper 13/64" hole in it) to anchor outer pushrod tube rear servo. Drilled 3/8" hole in firewall for future choke pushrod setup (currently undetermined). Pictured receiver only dropped in for testing.
Drilled prop. and spinner and installed. For DL-50 10mm main shaft use 13/32" bit. For 5mm bolts use 13/64" drill bit. Test fit JTec muffler with DL supplied nylon gasket.
Mounted DL ignition module on right of engine box (high enough to barely allow access to right cowl mounting screw ... but not touching cowl at top outer edge) with soft Velcro underneath. Drill a single small hole (lower) and loosely attach a tie-wrap. Also notice how far forward it is. Then, 4.8v ignition battery on left side with foam underneath. These locations are compatible with cowl-ring mounting system. Installed MPi emergency manual ignition kill switch on right side of fuse (just behind wing leading edge).
When building tank ... solder on 3 outer Dubro brass barbs with tubes not installed in stopper (avoid soldering in stopper when possible). Install tubes in stopper and be sure to install the 2 metal stopper plates. Soldering on the final 2 inner barbs and (carefully, slowly, evenly) bend the vent line, being careful not to crease it.
Leave muffler off to cut initial hole (for cylinder head) for completion of cowl ring installation steps. Then (with the cowl off) install the muffler on the engine and make a template out of heavy card paper. Transfer this template to the cowl (lining up the original hole for the head) and trace the new boundaries for the larger hole to include the muffler. Pictured here with JTec wrap-around Pitts style muffler (custom ... with 3 inch exhaust stacks). |
|
I left the rudder servo for last (to see where it would balance without it and then decide about placement). Surprise! ... tail heavy! Temporarily placed rudder servo mid-ship behind throttle servo (eventual pull-pull setup). Temporarily strapped in or taped on the few remaining items (pilot, all batteries, fuel tubing, switches, tail wheel assembly, etc.). Preliminary balance looks to be at 5-5/8" (middle of wing tube) with about 6 ounces of weight added to the firewall. The manual's suggested CG is 5-1/8" (leading edge of 1" dia. wing tube).
Use caution if you don't have a real "CG Machine" either and use my idea of a ladder instead. The ladder will collapse and plane WILL CRASH TO FLOOR if not secured, ladder is old and wobbly, or just generally not done properly. If your braces don't lock-into-place good, secure them. Use a chair or box to catch the tail. Rubber-band or tape foam rubber over feet. Cover front cross-brace to prevent a scratched cowl. Works fine for me but you have been warned. |
|
Install the rudder servo as per. manual. I used the rear-most slot behind the throttle servo. Depending on the orientation of the nearby throttle servo, you might have to put the servos shaft toward the back of the plane to avoid the arms hitting each other. If using HiTec servos, you will have to modify the large black wheel or the supplied metal servo arm. I choose to install the arm on top of the wheel instead of on bottom. I carefully ground-down the ridge on the top of the black wheel (so it would lay flat), and drilled the 4 smaller 3/32" holes. Use the supplied 2-56 screws and washers and screwed them in from underneath and into the control arm tightly. Instead of Loctite and cutting the screws (since they are on top with plenty of clearance), I finished it off with (4) 2-56 nylon insert lock nuts. This picture is not quite right any more ... Instead of using the outer holes in the metal servo arm, use the next set inward (which ends up matching 3" distance used in back) They must be equal.
On the rudder, hold the supplied black control horn in place to get an idea of where your hole goes and to find the plywood on both sides. Drill a small guide hole (close to but avoid actually hitting hinge-point tip inside rudder) straight through the rudder plywood (as per. directions on 8-32 hardware package ... 3/4" away from hinge, etc.). Be sure it went straight through, and if not, compensate when drilling the real larger hole. I choose not to cut the length of the 8-32 threaded rod until I have everything working (or maybe not at all :-). Slightly enlarge wire exit slots in fuselage if they are binding. Black rudder control arms "centers" are about 3" apart. Be careful not to over exercise rudder when testing. Max. travel is 4 inches (Use radio to program new end-points).
Cut a special triangular piece of hardwood, plywood, (or something like Spruce) about 3" long. Epoxy into rear of opening so new landing rear has a mounting area, along with some tri-stock or hardwood support rails underneath. Spring operation works best when the tailgear's tiller-arm is even with the rudder hinge-line (pivot point). The screws that come with the tailgear are very thin diameter (like servo screws) so I used some better/heavier self-tapping screws. Re-drilled an old pair of nylon aileron control horns, tapped for 8-32, and screwed on. Found some slightly stiffer springs than what came with the tailgear. Bent some "S" hooks from some stiff wire (so there would be less spring). Covered hole and exposed wood with white MonoKote (inside tail can later be accessed by just removing this piece of covering).
In addition to re-making the control arms for the elevators and ailerons, I also swapped out the servo control arms. This was done to be able to hit a more realistic "high rate" surface throw with better servo resolution. Use the bottom hole on the shorter blue aluminum Hitec arms, and bring the clevis down to the bottom hole on the surface side. While this setup might not be able to hit the "3D Rates" in the manual, they will reach 75% of them (which I plan to use as my "high rates"). So my High Rates will be using 90-100% of most of the servos travel resolution. I plan to use the manual's recommended Low Rates, and with this modified setup, even they don't have to be programmed down as much.
You can barely tell in the picture at the right, but be sure to seal your surface hinge gaps. You just do the bottoms and one side of the rudder. I used clear on the 2 ailerons and rudder, and white on the 2 elevators. |
|
New Elevator and Aileron Control Rods:
Some of the older pictures don't reflect it, but I re-made the 4 external control rods.
The rod is made from a one solid (properly sized) piece of 4-40 threaded rod. The 6-32 Carbon Fiber rod is slightly shorter and easily slips over the whole metal threaded rod. Epoxy or J-B weld the CF tube in place, and secure in place with nuts on both ends.
On the servo end, I installed a Dubro 4-40 ball link. The blue aluminum Hitec servo arm was 4-40 tapped in the bottom hole.
|
|
