Clutch issues

[buster1]

Not sure if this is the right place to post - but in reading over on the RR board - I have heard there are some clutch/clutch liner reliability problems. Guys either breaking or burning up clutch.

I am in the market for a 700, but wanted to know what the story with this is?? Or anything else one should know before buying this bird,

Thanks - much appreciated,
Jeff

[HELINHAWAII]

I have had no problems with mine. I think most that are having problems are due to the clutch being out of balance, clutch shoes breaking off (I'd bet due to alignment issues), clutch liners wearing down prematurely and/or clutch liners being too thin.

I'm no expert heli mechanic... but during the build, check your clutch and liner carefully. Your clutch should fit just barely inside the clutch bell and liner meaning that you have enough liner. At that point also, you should be able to see if one clutch shoe is bent a little too far in or out.

Also... Align has stated that some frames may have been drilled incorrectly leading to improper gear mesh. As a fix, re-drill the clutch block holes allowing the to builder to move that block back or forward as needed. I would think you'd just elongate the holes by a hair to get better gear mesh and center the clutch bell over the clutch if need be.

[MrMel]

Two clutches broken. I dialed indicated clutch and replaced the bell since that was not running true, didnt help..

The clutch is just too soft.

[Mercuriell]

My clutch disintegrated on about the 4th flight but no problems in the subsequent 30 and I have seen one go misaligned - I agree with Mr Mel - the shoes are just too soft

[Gscott]

It's definately an issue with the clutch itself. I have a brand new one that I just installed and I can squeeze the shoes together with my fingers. Hopefully Quick UK or Kasama can offer a solution since Align seems happy to keep selling $20 clutches every 20 or 30 flights.

[buster1]

yes, they seem happy doing that,
I am surpised thought - so many top guys flying this heli. - I guess they have someone changing the clutches for them,
The 700 looks like a great heli., but there are just too many people mentioning they have clutch problems - this is obviously a real issue.
I will wait for a while and see if they come up with a fix before I get one,
Thanks for info.,
Jeff

[tcast305]

yes, they seem happy doing that,
I am surpised thought - so many top guys flying this heli. - I guess they have someone changing the clutches for them,
The 700 looks like a great heli., but there are just too many people mentioning they have clutch problems - this is obviously a real issue.
I will wait for a while and see if they come up with a fix before I get one,
Thanks for info.,
Jeff

Buster1,

What you have to remember too is that there is alot more people that haven't had issues with their clutches. The online forums are a great resource of information, but they seem to make a problem more widespeed than it is. However, I'm not saying there is not a problem.

I have 2 Trex 700's. One has over 140 flights with no issues (that kit was from a early batch), and the other has 40 or so flights with no issues with the clutch either (that kit was from the 3rd batch).

Thanks.

[buster1]

Well, that is good to hear. I am just doing some research, not trying to bash the 700 - I really want to buy one!
I just hate taking them apart, unless for routine maintenance or the dreaded crash,
Thanks,
Jeff

[Gscott]

tcast,

The problem with that analogy (it's posted all the time whenever there is a problem) is only a small fraction of 700 owners post online. If the info posted on RR is to be believed then over 1000 700n's have been sold yet the "owners thread" is just over 150. So if 150 active 700n users are actually posting online then roughly 10% are having clutch issues. That's way too many. Also, many who have had issues with their clutches assume it was something they did and was normal. Read some of the threads and notice how many will say "my clutch lasted 20 flights but I assumed it was because of my 1 hotstart".

The clutch material is too soft. No question about it. If you want to see for yourself go to your LHS and squeeze the 700 clutch. You can almost touch the shoes it's so soft. Now go try this on a Raptor, Hirobo, or JR clutch.

[tcast305]

Gscott,

I understand what you are saying, but people post more when they have problems that when everything is good. I been keeping up on RR topic on the clutch issue, I counted 9 people and thats including the "people at their field".

I haven't picked up a replacement clutch yet so I can't comment on how soft it is. Maybe a bad batch of clutches? We just went thru with that with the ball links.

Thanks.

[Mercuriell]

As always it's a balance of price vs quality - Align offer a good product at cut price - MA offer a superb product but at twice the cost :roll:

[Stricker22]

I just burned out my clutch and am about to replace the clutch liner.. Does everyone just CA the new liner in place or is there a different way to get this replaced?

[Mercuriell]

Many people have used CA or 5 min epoxy - I like long setting epoxy as it seems less heat labile than the shorter setting stuff. JBWeld also got a following.

[4cyclic]

JB weld quick is good if you're in a hurry.

[cbdane]

JB weld quick is good if you're in a hurry.

Interesting. I've always found JB weld to be of a slow-setting formula, taking at least 24 hours to completely cure. Has your experience been different?

[HeliSmith]

I can testify to 30 minute epoxy gives it plenty of time to setup and clean off a bit don't be in a hurry. :thumbup: I will take mine out and have a look I like working on it anyway.

What are the signs of a clutch failing in the air? I have never had the pleasure. Only electric motors with the pinion slipping. I would assume it to be like that with the motor going high rpm.

[Gscott]

Luckily both of mine failed on the ground. What I noticed is the clutch will start grabbing very hard at idle. On my first one it was grabbing so bad the engine would start backward.

[4cyclic]

Interesting. I've always found JB weld to be of a slow-setting formula, taking at least 24 hours to completely cure. Has your experience been different?

JB Weld regular and JB Weld Kwik, about 60 minutes instead of 12-24 hours.

[cbdane]

JB Weld regular and JB Weld Kwik, about 60 minutes instead of 12-24 hours.

Ah, cool. I wasn't familiar with the "quick" flavor.

[djspark]

Mine broke after 21 flights.

[erniefritz]

50+ flights on mine and still going strong.

[dr.vision]

Yeah mine went aftern about 10 flights. havent had any problems since

[davo705]

Yes my links are developing some slop (is easy to fix).
Canopy could be stronger/ reinforced more at mounting points.
Nicer paint job too!

### BUTT we need a QUICK UK CLUTCH FOR THE TREX 700 PLEASE! ###

I know when clutch is going off as the drag on head builds up at idle!
Leave it too long and hard to start!
Any longer and it'll break.....

The quick uk clutches work magic on my rappy90 and the old rappy50!!

regards,

[Rototerrier]

Luckily both of mine failed on the ground. What I noticed is the clutch will start grabbing very hard at idle. On my first one it was grabbing so bad the engine would start backward.

Mine finally broke yesterday. 30 flights. It was grabbing just like Gscott says. I held onto the head and...bang crakle pop pop crackle...oh..that's not good...kill switch!

Damn thing was seated so hard into the fan hub I almost couldn't get it out. Boogered up the fan hub pretty bad, going to just replace it too. The little notches you use as leverage with the screwdriver are pretty much gone and I'm afraid, without them, I won't be able to get the next clutch off...in 30 more flights.

My buddy has a couple MA clutches that dwarf this thing. He had never seen my clutch until I had it out last night. He was absolutly shocked that it was so thin. I have to agree...it is about the same as the 600. I am pretty peed off about it.

$45.98 + shipping at GrandRC (the only place carrying the fan hub). If I have to do this every 30 flights I am going to be very bummed.

I don't think this particular issue is isolated. That clutch is too damn thin. This is a defect, right there with the crooked ball links and out of whack boom.

Edit: I want to add, I wouldn't let any of this stop me from purchasing a 700. This thing rocks when it's in the air! A few growing pains are expected. I am sure they, or someone else, will resolve this rather quickly.

[HeliSmith]

Yes Quick UK, Kasama, anyone? :DOH

I have to agree the 700n flies like an absolute dream. Well on 8v anyway never tried at on 6. :) Mad pitch and cyclic capability I am at 13/13 + 9 it could go more I think, due to this shim vs a main shaft collar idea is great.

Heres hope mine doesn't let go in the air... :thumbup:

Mike