moding a 700n to 700 f3c spec

[choppertastic]

I currently have a 700N but as i am wanting to head down the sportsmans route i am interested is the 700 F3C.

what i am trying to find out is it a simple case of changing the mixing arms and washout arms plus a bigger tail fin? i have already softened up the head with o-rings.

thanks for your advice in advance.

james

[Johnda]

Have a look here Align just announced a 700E F3C heli... - Page 7 - RunRyder RC Helicopter , page 7 second post down.

[Steve]

In no particular order......

• Soften the damping with the new red Align F3C dampers that are supplied with the 700E FAI kit (I'm not convinced by these yet, but haven't been out for yonks to fly).
• Increase the flybar ratio using the Align mixing arms from the same kit.
• Try some different paddles - Hirobo Freya ones are a great option as they have variable weights inside and don't break the bank.
• Fit a broad horizontal fin with no holes in it - Carbon Hirobo Freya one from Quick UK is a good option.
• Slightly shorten the boom supports to bring the horizontal fin a bit closer to the fuselage.
• Add loads of weight to the inside of the canopy up front to get the model just slightly nose heavy with a full tank of fuel.
• Make sure you're not using a 3D pipe on the engine - get a dedicated FAI one.

Things that are talked about on various sites which I've tried but don't seem to make any difference, so I went back to stock settings:

• You can change the ratio on the washout arms but I found it made little difference to the flying so I went back to stock.
• You can centralise the Delta Offset with a 9mm spacer behind the main blade grip balls but it makes little to no difference, so I went back to stock settings.

[choppertastic]

I've already softened the head with o-rings and i'm running Robbe Cuatro paddles which i think have made a huge difference

[Steve]

Also, use heavy blades like the Radix FAI 710s @ 230g or the SAB 705s @210g (I think)

[choppertastic]

Also, use heavy blades like the Radix FAI 710s @ 230g or the SAB 705s @210g (I think)

Will give that a go. Currently running NHP Razor 710s. Not sure of their weight

[Steve]

I've tried most of the above so far on mine at different times, some of which I've put back to standard settings. My 700 is quite stable and tame these days and tracks well through the air. My setup is:

Radix 710mm FAI main blades.
Radix 105mm tail blades.
YS91SR + Hatori 995 pipe.
Standard white Align paddles with JR Vibe 90 flybar weights all the way out at the paddles.
+/-10.5 degrees collective pitch with +12.5 in throttle hold.
Cyclic pitch around 5 deg with swash mix settings down around the 35 mark on the Tx.
New red Align dampers.
Increased flybar ratio with G Force mixing arms - these are an expensive option - the same result can now be achieved using the Align mixing arms from the 700E FAI kit, but these have only recently come out.
Spartan DS760 gyro with Futaba 9256 servo.

The blades, pipe and top mixing arms will make the biggest improvement. If you're building a model from scratch, then choosing the right blades and pipe is easy from day one and saves having to splash additional cash later.

As a thoroughbred 3D helicopter, de-tuning the 700 to FAI standards is a bit of a challenge, but achievable without much expense. I've recently added a chunk of expo to the cyclic and rudder controls (don't generally use it) to try to remove unwanted elevator inputs (from my dumb thumbs) during rolling moves etc.

I've tried the big flat horizontal tail fin, the neutral Delta Offset and the different washout mixing options, all with limited (if any) improvements. However, my heli still doesn't slow piro very well so I should probably look at the c/g again when I get around to it.