Thursday, April 26, 2007

Canopy Mod

Did the canopy mod to prevent it from slipping out on backward flights. Item needed - 10mm long M3 cap screw.

Drill a hole on the canopy clip big enough to for the M3 cap screw to go through.
Put the canopy on n mark out where the screw should be. Screw it in place.
The canopy should clip on nicely to the cap screw, this will prevent it from slipping.

Main needle screw loose

On a flight on the titan few days back, the engine started to sound funny, n heli started to wobble alot. I landed and found that the high end needle was loose! It got unscrewed while in flight probably due to all the vibrations. The black clip was not pressing onto the needle tight enough. Those using TT50 engine may want to take note. Unscrewed the high end needle out and bend the black clip to tighten the hold on the needle.

Adiós trex

Sold off my Trex a few days back. It has served well for the last 6months, hope it will serve its new owner just as well. But seems like the trex is getting out of fashion now, had to reduce my selling price quite abit to get people interested. The in thing now is tt's mini titan, everyone is ditching their trex to get it.

I say hold your horses first. Trex is a tried n tested, proven platform that has gone through many revisions and improvements. As i mentioned before it is a good heli to start on, with cheap spares aplenty. The mini titan is still new and there are some issues yet to be iron out. Moreover spares are quite limited.

One last tribute to trex

Wednesday, April 18, 2007


Recently, around past one year or so, the RC scene in SG seems to have pick up abit. More people are getting interested and taking up this hobby despite the lack of open spaces in land scarce SG.

The availability of cheaper RC products especially those made in China has lowered the cost of entry into this hobby and the convenience of electric flight have certainly paved the way for many to fulfill their childhood dream of flying a radio control aircraft. Quite a few enterprising hobbyist have set up shops to cater to this increased demand.

Today visited a newly open LHS during lunch. Located at beauty world plaza, the shop seems like a one man show,being a subsidiary of Taiwanese hobby distributor The parent company is one of the sponser for 3DX to be held here later this year in Oct. Owner is quite a nice chap, offered us drinks while we chat abit. He said they set up a small store here to test local market first.

He stocks mostly heli stuff catering to the nitro crowd at the moment.He brought in brands like Model Avionics, NHP, Quick UK, Zimmermann which were locally not available previously. The prices of most of the accessories under the RCT brand are cheaper than rotor's excellence. The items were neatly displayed on shelves.

Some good deals like a pair of oem wood blades for trex going for only 10 bucks, the prolux manual fuel hand pump is half price of rotor's. Arghh, I could have save quite abit buying the nitro accessories from here.
Here's what i bought today. Tail support bridge for the titan and Triflow , oil with teflon for lubrication of the main shaft and tail shaft after flights.

With so many RC suppliers now in the local market carrying a wide variety of stuff, the prices have become fairly competitive. There were already a few price wars, the winners will be us hobbyists. Well, i definitely will be visiting there again, its only 10mins from my place. Ho ho ho. Now if only they stock up Coolpower fuel, it will be prefect...

Sunday, April 15, 2007

BR field , TBP weekend

Went back to the east during the weekend for some funflys. Had a fun time chatting with the BR gang whom i haven flown with for awhile. Seems like the planes there have been all UPSIZED like mac's evm. LOL. They all flying much bigger planes now compared to last time, made my filton extra looked really tiny. ahaha.

Sunday evening met up with some flyers at tampines bike park to fly heli. Mostly raptors and an evo. Got to see some nice 3D action close up from one of the young talented flyers. He executed his moves very low to the ground, tats 3D. Good to fly with people flying similar machines, get to learn alot from them.

Br gang
New AM
DIY plane with a cute pilotExtra KE
Kel with his huge ass motor and huge ass plane.
WY hovering

Yellow seems like a favourite colour
Root bear anyone?Need to get one of these

Really smokey with so many helis flying at the same time, some more they use 20% n 30% nitro!Pitch screw servo came loose, lucky he managed to land

Thursday, April 12, 2007

Madien flight

After 3 weeks of assembling and setting up, finally madien the raptor titan last weekend with help from CKS. Thanks!. Change the lipo to a bigger one, 3s1800mah to get the correct C.G.
I started at 3.5 turns out on the high speed needle and 3 turns on the low. We could not get the engine to start and i was getting anxious. Slowly trimmed open the throttle to around 30% and lean the low speed needle 1/4 turn before it got started. Quite a bit of fuel was splitting out from the exhaust at idle indicating a rich setting. The new engine needs the piston and ring to seal properly so the extra lubricant would help wash away any debris.
I let the engine idle for awhile before proceeding to hover the heli slightly above ground. After awhile i realized i forgot to remove the glow starter. Didnt know as the canopy wasn't on. lol. Landed the heli and removed the starter. Wah it was hot, n prob burnt out the battery indicator on the glow starter.

Went on to hover the heli for 30seconds then idle again for 30seconds, repeating the cycle for the first tank. The sound of the nitro engine was intimidating and smoke was plentiful, made me almost forget that im in control. As the heli idle, i touch the back plate to test the temperature. It was cool to touch.
The first tank of fuel finished fairly fast. I let the engine cool down before refueling. Ah as i refuel, i forgot to clip the fuel line to carburetor and fuel started leaking out of the engine. First time on nitro, dont know the SOPs yet. Quickly stopped, clipped the line and resume refueling.

I proceed to crank start the heli but it wouldnt start. At first i thought was engine flooded due to the refueling. Later found out the fan has dislodged from the engine and got stuck at the clutch bell. Dam no more flying for that day. Had to borrow a crank locking tool to tightly secure the fan down.
Went back to run in the engine the next day. Repeat the hovering and idling cycle for the next 4 tanks , gradually prolonging the hovering period. Next 4 tanks started to do abit of flying around. Slowly getting use to the size and noise. So far it feels more stable and far more easier to orientate. Finished nearly a gallon now. Fun!

Sunday, April 08, 2007


With so many servos, plus the gyro and bec, the wiring can be quite a mess. The wirings should be kept neatly to prevent interference and for easy serviceability. I planned to keep it simple and spent quite abit of time arranging the wires.

Zip ties are great for bundling the wires together but the edges are quite sharp and with so much vibrations on the heli, they may cut into the wires. A simple solution is to use some fuel tubing as cushion.
Tidy up the gyro wires and zip tie them to the hole at the back of the frame.
The wires from those servos in the servo frame are bundle together and 2 small holes are made in the back of the servo frame to fastened them down. Some of the wires were too long so loop them around the gaps at the back of the servo frame. The BEC is installed in the empty servo space in the frame. The gyro wire and bec wire were bundled together.
Lastly the antenna is routed out of the receiver strong box through fuel tubing into the antenna tube at the bottom of the skid. The end of the tube is zip tied to the alum support rod.
Finished up the canopy and its good to go.

Friday, April 06, 2007

Extra time?

Something unheard of, something i think never happened before. Winds is blowing from NE again after 1 month and we are sloping in April. Weird. Seasons normally end by march. This year it ended in early march, and so we thought. Strangely enough, the winds picked up again this week and it was almost peak conditions winds , hitting 13knots yesterday. Crazy weather.

Went down today, winds was quite consistent although fairly light. The usual suspects were there lol. Great to see them again, flew abit, chit chat abit more, most of them were pleasantly surprised by the winds, some managed to madien their gliders that were meant for next season. Be it due to global warming, wind god taking pity for the short season, no one is complaining about the extra slope time. Its a bonus, take it and fly...

Usual suspects
The guy with the biggest planes was flying the smallest and he flew it thermal scale style. lol.
Look where the bug ended up

Wednesday, April 04, 2007

Setting up

Servos installation and setup. This is the most critical part of the built IMHO. It will determined how well or bad the heli will fly. A poorly setup bird will be hard to trim later on. A comprehensive setup can be found at raptortechnique, i did some adjustments as mine was a titan with push-pulls.

The servos were first installed as per manual and the push-pull links setup to the recommended lengths but not snapped on yet so that adjustments can be made later on.

The goal here was to work from the swash up and make sure that at half stick, the swash plate is level, then the wash out arms are level, followed by mixing arms level and then lastly the blade grips at 0 pitch. Make sure radio is at half stick at the start of setup! I use the throttle curve to ensure it to be digitally half stick.

To level the swash , i used 2 pieces of balsa with equal height as a guide. Started with the elevator since the A-shaped elevator control arms are fixed. Level the swash with the balsa pieces.
Fix the servo horn slanted at an angle on to the servo. Adjust the length of push-pull linkage rods so that they can snap on to the ball links on the control horn. The important part here is make sure both the push-pull linkage rod are equal length else it will cause binding. Use sub-trim to finish off keeping the swash level.
Next do the aileron. Again level the swash, keep the aileron linkage rods equal and aileron push-pull rods equal length.
The ball link on linkage rod A has the thunder tiger wordings facing inside the swash, while that on B is facing out to ensure both are same length.

For the pitch, adjust the collective control arm such that the washout arms are level. Then adjust the length of the vertical connecting linkage rod so that it can be 90 degrees to the pitch push-pull subassembly. This is to get same amount of movement up and down pitch,prevent differentials. The push-pull subassembly will be slight slanted when setup properly and not perfectly horizontal.Next adjust the mixing arms' long linkage rods to make them level. Then the short linkage rods to get blade at 0 pitch.
For the rudder setup, the best position for tail centering is to adjust the rudder link so that you have 4.5mm between the pitch slider and the tail rotor casing. This is to get around 15 degree of tail pitch built in to counter main rotor torque. Then use a horn with a hole far enough such that the linkage rod can be as close to 90 degree as possible to the horn. Finish up by CAing the 3 rod guides to the tail boom. Set up the gyro as per normal.
For throttle, use the ATVs and adjust the linkage rods to ensure no binding at both ends before snapping on the links.