Hawk owners. Poll.

[marked23]

I didn't glue my drive-wire guide tube into the boom. I just slid it in there and it seemed snug enough to stay put.

I broke two drive wires in two months. So I'm thinking this missed step is the culprit.

Agree?

[bighands3d]

I'm not sure about that I never glued mine when I was flying them. The only thing that i did glue is the white inserts that go on the brass tube they need to be glued in place.

If you running a 401 or some heading hold gyro I recomend the SS tube drive. it will stop the breakage of the wire drive. what happens with the wire drive on the HH gyros is that it winds up and then breaks. The upgrade TT will sovle this.

and make the tail feel more solid.

[ThBrtmn]

I didnt at first but then I could hear the tail boom rattling so I put some JBWeld on the ends and it quit. I never had a prob with the drive.

[rstacy]

Glue the tube in place. You don't want it walking around the boom.

There is no doubt that upgrading to the TT drive will solve the problem but that takes away from the attractive $159.00 price.

I converted to the larger drive wire per Steve H and it worked very well.
Total cost 15 cents and about 30 minutes time.

The biggest problem with the conversion and using a HH gyro is that the tail rotor pinion likes to clean the teeth off of the main gear. I haven't found a fix for this yet.

[ThBrtmn]

Ray...
With the upgrade from steve your maingear got stripped? Thats weird...

[rstacy]

I'm not surprised. There isnt any front pinion support. The stronger wire with the faster gyro and servo gives the pinion the required force to jump up on the main gear and clean the teeth off.

[ThBrtmn]

I see your theory and I will raise you a question?
If the stronger wire is causing it to jump... Why then wouldnt the TT, which is stronger than the wire,cause it to jump as well? What servo were you running before and after the upgrade?

[rstacy]

My guess is that the thinner wire with wind-up was absorbing the shock of a faster servo.
The heavier wire does not absorb the shock but instead transfers it to the next weakest link which is the pinion to main gear connection.
When HH gyros first came out, MA and Bergen were coming up with front pinion supports to help solve this problem. Back then it was easy to strip an Xcell main gear. Even today I see that there is a pinion gear support available for the Vigor to help with the same problem.
I havent looked into the Hawk problem yet. Making the pinion to main gear tighter may help but is not the correct fix.

I dont remember what servo I had on there before.
Now I have a CSM Micro 560 and 8700G servo.

[SteveH]

Guys,

Here is a copy of a post I put up a while back on "the other site" about the stock drive wire problems. This is the cause and the solution to the problem of the wire breaking.

The most important thing to making the wire drive live a long life is to properly align it during installation. By alignment I mean to check the runout of the wire in the tail rotor box input shaft after tightening the set screws. If there is any runout after tightening the set screws, go back and adjust the two screws until it runs true with no "wobble" at the joint between the wire and the input shaft.

If this is done properly, the wire drive gives little or no troubles, and if it is not done properly, I guarantee you it will break as well as cause vibration problems.

You can also go to the larger wire and that works even better. Almost as durable as the torque tube and not near the cost. As a mater of fact, I will not build a heli with a wire drive without installing the larger music wire from the get-go.

Sorry I haven't been around here much lately,but I'll try to do better.

[SteveH]

One more thing concerning the guide tube, if you don't install the wire correctly, with little to no runout, I guarantee you no matter what type of glue you use or how much of it you use installing the guide tube, the glue will break loose and the guide tube will move. This will be followed shortly by the drive wire breaking.

So again, the most important part of installing the drive wire, is getting the runout at the juction of the tail rotor input shaft to a minimum.

[ThBrtmn]

So why doesnt the TT strip out the gears? Does it have some sort of absorbing mechanism that I'm not getting/seeing? :dontknow

[SteveH]

Bart,

IMHO the stripping of gears has nothing to do with tail rotor drive media, no matter which it is. Gear stripping is caused by installation of the gears with improper lash (too much lash), or tunning the tail rotor in something other than air. :wink:

[rstacy]

Bart,

IMHO the stripping of gears has nothing to do with tail rotor drive media, no matter which it is. Gear stripping is caused by installation of the gears with improper lash (too much lash), or tunning the tail rotor in something other than air. :wink:

I think we will agree to disagree on that.
I don't even know if the mesh is adjustable but both of the Hawks that we have here in our group like to strip the main gears.
It comes assembled and other than changing the gear, I haven't spent a lot of time there.
I am also certain the the tail drive meadia has a great impact on the stripping of the gears.
As I said, the wind up and slower tail rotor servos will cushion the blow.
Speed up the servo, cure the wind up and something has to give.
I'm not griping here. It is what it is.
Anyone that has been around for a few years will remember that this was a problem when TTs and HH gyros first came out.
I cant comment on the TT. I have never had one but I would think it is the same.

[SteveH]

Ray,

I know we will disagree on this one, but the fact of the matter is, the Falcon and the Raven 50, which I am currently flying, do not have a crown gear stripping problem and that is with a torque tube, 401 gyro, digital servo, OS 50 engine, and 95mm tail rotor blades.

Now, if there is no problem with the gear, the same gears mind you, in this application, why would there be a problem with the Hawk Sport? :wink:

[rstacy]

Dont know. Just my luck I guess... :(

I dont know enough about all three machines to know if the design is identical, fit is the same, or the gear ratios are the same.

[ThBrtmn]

Ray...
I'm flying the 9253/401 combo on my hawk. Is this slower than what you are flying?
Just for general knowlege...
Last week I was searching for a "pitching up" problem. Replaced the Swashplate(which fixed it) and put the heli in a "factory settings" model so I didnt screw up my current program...Anyhow I was verifythat the swash was level and pitch was good at 50% 0 degrees. Sooooo. I forgot to change models back, R/L cyclic was reversed, tried to corred the right direction(wich was over correcting in the Rvrsd servo) and over she went about a foot high. Broke my vert tail fin OBVIOUSLY :roll: bent spindle and broke a blade...everything else was cool. LEARNING MOMENT :mrgreen:
Verticle fin was in half ...continued to fly it this week without putting a new one on....
...here comes my point... Set it down once earlier this week and my MAH CF(gift) tail blades caught some earth. It happened again today( I wasnt flying it) BEFORE I finally put a good fin on it. Anyhow, I checked the teeth on the main gear and on the tail gear...everything looked fine. If my servo/gyro combo is slower with the TT I can see your point... But with the TT, Hard CF tail Fins plowing the earth with no damage, I dont see where the gear hungry drive gets its appetite from... What is causing that thing to eat the gears?