TRex 700 Dampers

[Steve]

I've had a feel of those new red dampers as well.
Definitely not as firm as the blacks
Still firm-ish though.

We will have stock very soon.
Cheers,
Rob

Phew, at least now I know they are genuine parts.

[Steve]

Just got around to fitting the new dampers. They are certainly no softer than the black ones I took out, and almost feel harder (the black ones have been well used though). But, they slide into the head hub a lot easier and the spindle slides through them a lot easier which suggest that are an ever-so-slightly smaller outside diameter which will allow for more spindle movement and give the softer damping.

The mechanics makes sense, so we'll see how they go once the weather warms up enough to allow my YS engine to run (while I was doing the swap, I have also re-routed my crankcase pressure line to plonk the check valve next to the engine and keep it warm rather than out in the open air).

[trillian]

'Just curious Steve, have you done any mods to the Rotorhead to change to zero delta, or change the flybar ratio etc.? I was just reading a thread by Nick Maxwell about flipping the grips and adding longer ball link standoffs.

I am about to try a flybarred Trex 700 head on a Raptor 90 airframe ('long story but I had this 700 head for another project and then discovered it wouldn't work for that).

[Steve]

'Just curious Steve, have you done any mods to the Rotorhead to change to zero delta, or change the flybar ratio etc.? I was just reading a thread by Nick Maxwell about flipping the grips and adding longer ball link standoffs.

I am about to try a flybarred Trex 700 head on a Raptor 90 airframe ('long story but I had this 700 head for another project and then discovered it wouldn't work for that).

Yes I have.

I tried the zero delta mod with 9mm spaces on the blade grip balls and it made zero difference so went back to standard balls.

I've currently got the G-Force mixing arm set on which can increase or decrease the flybar ratio and I've got it set to maximum effect (i.e. opposite way around to 3D) and this is a significant improvement.

I've also run the heli with the Radix FAI (very heavy) blades and they worked a treat at reducing the floating up and down in the hover. Currently got an old set of SAB white 710s on it which are quite a wide chord and they work quite well too, even though they aren't anyway as near as heavy as the Radix FAIs.

I've got JR Vibe 90 flybar weights on half way along the exposed flybar section and the stock Align white paddles.

For a while I tried a big flat horizontal carbon fin from a Hirobo Freya as this supposed to improve the forward flight and rolling characteristics, but I couldn't tell much difference that I couldn't attribute to my thumbs, so have gone back to the stock Align fin.

I've got the Hatori 995 (or is 955) pipe on the engine and this made a good improvement over the previous SB19 in the hover, and I've got one extra shim in the engine head - this engine has always been a tad jumpy in the hover from new, and at the moment is working quite nicely with this shim, fuel (MT Coptamix 20%), pipe and plug (Enya No4).

One thing I've never messed with on this heli is the C/G. I've had this heli for about 15 months now and have never stripped a main gear, never had a ball link break, never shed a tail hub or shaft and it has generally been a trouble-free ride. I did recently re-glue and pin the tail boom supports and have changed the dampers a couple of times before today.

Looking forward to trying these dampers

[Steve]

Tried the new red dampers today and the damping is harder than the original black ones! They felt harder in the fingers but also slightly smaller so I guess they would be an improvement. Sadly, no. Pointless exercise!

But at least my SDX damping experiment was a success.

[GIXERMAN]

Align tw say red dampers 80 and black dampers harder 90

regards

[Steve]

Like I said, the 'new' red ones were physically harder than the 'used' black ones when squashed between the fingers. In flight, the heli wobbled all over the place at low head speed with the new ones fitted, much more so than with the old black ones. Maybe they'll bed in?