Head Dampers

[mrivers]

Abrupt cyclic inputs cause my heli to wobble pretty bad. Anyone else here think the head dampers are too soft? Ideas for replacements?

[rotorhead58d]

my head block is way too big. i think the spindle shaft wore it out...reemed it. new head block for me. there was a guy on rc groups that did a mod with a headblock. he put a spacer inside the block, and drilled the head out to 5mm

[mrivers]

I don't see how it's possible to ream out the head block. The spindle can only move up and down on each end.

Anyhow, I found a solution, taken from the Trex450 forum. RC fuel tubing. I replaced both dampers with 5OD x 2.5ID (mm) fuel tubing that I had laying around from my rc car days.

Holy cow!!! The wobbly goblin is gone! I just tried a couple tic tocs (in gusty wind), and the heli was smooth as glass at each end. Before, I felt uncomfortable doing them as the heli would wobble badly.

I rate this mod: Kick Ass!!! :thumbup:

[rotorhead58d]

I don't see how it's possible to ream out the head block. The spindle can only move up and down on each end.

Anyhow, I found a solution, taken from the Trex450 forum. RC fuel tubing. I replaced both dampers with 5OD x 2.5ID (mm) fuel tubing that I had laying around from my rc car days.

Holy cow!!! The wobbly goblin is gone! I just tried a couple tic tocs (in gusty wind), and the heli was smooth as glass at each end. Before, I felt uncomfortable doing them as the heli would wobble badly.

I rate this mod: Kick Ass!!! :thumbup:


finally! someone finds the fix for the head. you have my total respect.:noteworthy

[stoatnchips]

....been looking into this a little this evening and and its really down to the material used in the dampers. The standard ones are 3.0mm x 1.0mm Nitrile O-Rings.. i think, so there are 2 ways of going:
First is mrivers' solution, which is to replace them with way oversized rings, in this case fule tubing - if its silicone, it will work great, but wear away very quickly.
The second route is to replace the stock ones with something like Urethane ones which have a MUCH better wear resistance and are stiffer than the stock Nitrile rings.Its a bit over techie and i'm not holding my breath on an answer, but does anyone have a clue what the Trueblood Damper elastomer is? Can't see its gunna be too hard to source 3.0mmx1.0mm Urethane O-Rings if its that!

[psindrup]

I don't see how it's possible to ream out the head block. The spindle can only move up and down on each end.

Anyhow, I found a solution, taken from the Trex450 forum. RC fuel tubing. I replaced both dampers with 5OD x 2.5ID (mm) fuel tubing that I had laying around from my rc car days.

Holy cow!!! The wobbly goblin is gone! I just tried a couple tic tocs (in gusty wind), and the heli was smooth as glass at each end. Before, I felt uncomfortable doing them as the heli would wobble badly.

I rate this mod: Kick Ass!!! :thumbup:

Cool

What material is that fuel tube made of? Silicone?

Is it "hard" or "soft"?

Peter

[mrivers]

No idea what it's made from, but it seems considerably stiffer than silicone tubing (not RC related).

I attached a picture of it:

[rotorhead58d]

hey, whatever works. i'm getting some fuel tubing and giving it a shot. i will bend grip screws enough to check it often. lol

[choppersuey]

Hey Guys, I was wondering what the Deal with so called Replacement dampers ?

if you ask me the " 203311 Damper Rubbers Pack Gaui Hurricane 200" is the Canopy Grommets . not dampers for the Head . the ones in the head are O rings not Grommets.

BTW I was thinking Tygon tubing used in labs might work because it is Polyurethane based . problem getting correct size can only get close but not perfect. US Plastic sells it for about 0.10 a foot (US)

The fuel tubing is usually Silicone (very soft) so might not last very long .

Thanks for any comments on the 203311.

Hope i did not hijack this thread.
http://www.readyheli.com/v/vspfiles/templates/1/images/clear1x1.gif

[stoatnchips]

You're right, they are just "Vibration Dampers" for the Canopy :roll:
I've Not heard of Tygon tubing... but if its urethane based then i guess its a good match! is this like the tubing used in fish tanks... clear but stiff, if so it will probably work.

[jimgrant]

found this, maybe if we all got an order in for some, they would supply us


http://www.aberdeenseals.co.uk/orings.html

[rotorhead58d]

found this, maybe if we all got an order in for some, they would supply us


http://www.aberdeenseals.co.uk/orings.html

put me down for 20 of them if you order them.:thumbup:

[mrivers]

Can we just fill the head with hot glue? :)

[Gr4yb3ard]

Yeah, hot glue, JB Weld.... Rotor and I were just discussing epoxying a head. Hot glue sounds like a worthwhile experiment, seriously... (even easier to un-do).

Other forums have pretty much <solidified> thier heads with good results. The last 3d item I heard about on CP's was using ball bearing units in place of the o-ring dampers. I'd say that's a bit more solid...

I'm nowhere good, but I <like> tightening up the head. Flybar weights and goosy dampers are starting to get tossed, am I learning? or listening to gossip?

This stuff does feel better though, a sloppy head seems to be the A-ticket to a crash for me, FWIW.

Hokay, the fuel tubing has worked on other heli's for some time, I'd say I suspect so will just about any pliable material, given the correct damping characteristics and loading.

But if using fuel tubing, I get the diameter and wall thickness, but how long do you cut the section to get good results???

Anybody pre-loading dampers with shims?

Gr4yb3ard

[rotorhead58d]

Yeah, hot glue, JB Weld.... Rotor and I were just discussing epoxying a head. Hot glue sounds like a worthwhile experiment, seriously... (even easier to un-do).

Other forums have pretty much <solidified> thier heads with good results. The last 3d item I heard about on CP's was using ball bearing units in place of the o-ring dampers. I'd say that's a bit more solid...

I'm nowhere good, but I <like> tightening up the head. Flybar weights and goosy dampers are starting to get tossed, am I learning? or listening to gossip?

This stuff does feel better though, a sloppy head seems to be the A-ticket to a crash for me, FWIW.

Hokay, the fuel tubing has worked on other heli's for some time, I'd say I suspect so will just about any pliable material, given the correct damping characteristics and loading.

But if using fuel tubing, I get the diameter and wall thickness, but how long do you cut the section to get good results???

Anybody pre-loading dampers with shims?

Gr4yb3ard

lot's of ideas in that post. take note kids.

[mrivers]

I cut it a little thicker than the original oring. I wedged it into the head as best I could, and then smashed it in with the brass bushing/blade grips. A little excess has squeezed out, but it's not an issue.

[choppersuey]

http://www.gaui.com.tw/images/ps/203850.jpg

NOt sure if this old or New but hope helps someone.

[rotorhead58d]

http://www.gaui.com.tw/images/ps/203850.jpg

NOt sure if this old or New but hope helps someone.

i think you may have just solved the great mystery. there it was in front of us in black and white. tisk, tisk.:thumbup:

[choppersuey]

now to find those stickers :Slap

[rotorhead58d]

funny, i was just trying to figure out how to cut a sticker to that size. lol

[rotorhead58d]

as a last desperate attempt to find the missing stickers, i looked in the box my gaui came in, and low and behold!































they weren't there. back to the drawing board:arggg:

[choppersuey]

well your blade grip bearing's that is.

:arggg: its been bothering me why one blade grip is sluggish and one is stiffer . this will also cause the flybar to not dribble between your fingers. (yes both have the tiny brass washer , between spindle and first bearing).

anyway I toke a real good look at the edge were bearing is suppose to butt up against in blade holder(blade grip) internal hub side. one had a tiny gap the other did not . so then I had to figure out how to measure . so toke a long brass fly bar weight slide it into blade holder (little step toward blade) then used a dial caliper . sure enough one was out more then the other .


I popped Bearings out . cleaned blade grip with Q'tip . cleaned bearings with a brush (under mag glass as always) . then reassembled . measured, both the same now .also no Gap.

then put the Blade grips back on (make sure tiny brass washer is there). BINGO !!! both grip super slippery even with bolt tighten. :clappp

later ill have to put Green Loctite on bearings mating surface and inside blade holder like a Trex(use a q'tip to apply don't get in races).

I am starting to wonder if this causes heli to sometimes fly great and other times fly terrible. the blade holders might be floating back and forth and if dirt gets in there the blade holder rubs against hub or the brass(stepped) O'ring retainer.

the spindle is now more predictable when you check dampener by rocking blade grips.

I left green locktite off for now, because I am still checking assembly.

Figured i would mention my findings .

BTW just dawned on me the .04MM Sicker is only .0016" thick Dam that is thin! (one grey hair) ;)

[brandon_8]

well your blade grip bearing's that is.

:arggg: its been bothering me why one blade grip is sluggish and one is stiffer . this will also cause the flybar to not dribble between your fingers. (yes both have the tiny brass washer , between spindle and first bearing).

I've noticed this happens on mine too. One of the blade grips moves just fine when the pitch changes but the other is slow with less range of movement. (at least I think this is what your describing)

I thought something was probably bent but when I got a min to look it over, I couldn't really see anything tweaked or noticably bent. I'll check for that gap you are talking about when I get home tonight. Nice find and thanks for the post!

[choppersuey]

if you disconnect links to blade grip it should fall by its own weight if it stays something is wrong.

[rotorhead58d]

i'm sending the head and blade grips to trueblood on monday. we will finally have dampers that are worth a damn.:thumbup:

i will let you guys know when he sends the parts back to me.:banana