RunRyder RC
WATCH
 1 page 2089 views POST REPLY
HomeAircraftHelicopterAlignT-REX 700N › Clutch adjustment on 700n?
10-22-2013 09:31 PM  4 years agoPost 1
meowguy

rrVeteran

Saco, ME

My Posts: All  Forum  Topic

The clutch on my 700 nitro grabs too early and I want to adjust the spacing between the bell and the clutch lining. Am I correct that the only way I can do this is to chuck the bell in an engine lathe and turn it down a few thousandths of an inch? I am running a Quick UK clutch with the stock bell and this was not the happiest marriage.

Obviously if I still owned a lathe, I would just pull it out and do it. But no longer having one, I would appreciate your ideas.

"Sweet dreams and flying machines in pieces on the ground." J. Taylor

PM  EMAIL  GALLERY  Attn:RR  Quote
10-22-2013 09:41 PM  4 years agoPost 2
dchekas

rrKey Veteran

Farmington, CT

My Posts: All  Forum  Topic

Is it grabbing at idle?

Chocking it up in a lathe would be the best method of course.

I've carefully and slowly sanded a slightly dragging liner down by hand as well, frequently reinstalling and checking the bell over the clutch until no drag was felt on some machines.

You could also have a friend hold the rotor head and bump the throttle up and "wear it in" slightly as well.

You want that clutch gap to be as small as possible, allowing the engine to idle without dragging the blades, but engaging quickly as you accelerate out of idle. This will help clutch life tremendously. Too large of a gap will result in premature clutch failure.

Team Align, Team Futaba, Team Byron Fuels, Team Thunder Power

PM  EMAIL  GALLERY  Attn:RR  Quote
10-22-2013 10:10 PM  4 years agoPost 3
meowguy

rrVeteran

Saco, ME

My Posts: All  Forum  Topic

Is it grabbing at idle?
Yes. It's kind of an alligator wrestling match to get it out to the flight line.

Do you think the hold and accelerate method could give the clearance needed?

"Sweet dreams and flying machines in pieces on the ground." J. Taylor

PM  EMAIL  GALLERY  Attn:RR  Quote
10-22-2013 10:33 PM  4 years agoPost 4
dchekas

rrKey Veteran

Farmington, CT

My Posts: All  Forum  Topic

Done carefully, I've seen it work OK on machines that had some excessive drag.

Before you proceed, it's fair to assume this is a fresh clutch/liner that you've installed and you're seeing it drag?

If the machine has been fine, and suddenly it's dragging, your clutch has likely broken.

On a new assembly, a little bit of drag at is normal. This will wear in after 20-30 flights, and you'll have essentially the perfect gap.

It sounds to me like this is more than a little drag though.

Team Align, Team Futaba, Team Byron Fuels, Team Thunder Power

PM  EMAIL  GALLERY  Attn:RR  Quote
10-22-2013 10:56 PM  4 years agoPost 5
meowguy

rrVeteran

Saco, ME

My Posts: All  Forum  Topic

I will give the hold method a try but if it doesn't settle in quickly it's all coming out and off to the machine shop. Thanks for your help.

"Sweet dreams and flying machines in pieces on the ground." J. Taylor

PM  EMAIL  GALLERY  Attn:RR  Quote
10-23-2013 12:30 AM  4 years agoPost 6
jschenck

rrProfessor

La Vista, NE.

My Posts: All  Forum  Topic

Something to check if you do pull it apart is the runout of the clutch. If it's off center then the gap might be right but it'll still grab on one side.

Measure the bell and the clutch. I look for a measured gap of .008" - that works well for me.

Two ways to get a bit of clearance if the parts are in your hand:

1. Just use sand paper and take off a little from the liner in the bell. Not a clean and accurate as a lathe but I've done that for minor clearance.

2. Put the clutch and starter shaft into the bell and hook up a high speed hand drill to the starter shaft. You can use this as a way to cut off the high spots without risking getting clutch liner inside your engine. I've even put a small piece of like 250 grit sand paper caught into the edge of teh clutch ears to run around in the bell.

The only issue I have with the bumping the engine while it's running is the thought that the engine is sucking in clutch liner dust - which is harsh stuff for the engine. Having said that I have done this before and it'll work if it's close but just a bit tight.

PM  EMAIL  GALLERY  Attn:RR  Quote
10-23-2013 04:10 AM  4 years agoPost 7
Glenn Goodlett

rrApprentice

California

My Posts: All  Forum  Topic

Just run it. About the time it seems just right, it will break.

PM  EMAIL  GALLERY  Attn:RR  Quote
10-23-2013 04:13 AM  4 years agoPost 8
jschenck

rrProfessor

La Vista, NE.

My Posts: All  Forum  Topic

been flying 700n since 2009, never broke a clutch - I have seen them break but I've haven't broken one. For me what has worked is using the blue liner, I was using Raptor 90 liner material - and making sure the gap is very close to .008" and runout is .001" or less.

PM  EMAIL  GALLERY  Attn:RR  Quote
10-23-2013 11:00 AM  4 years agoPost 9
meowguy

rrVeteran

Saco, ME

My Posts: All  Forum  Topic

All good ideas. Thanks for the help.

"Sweet dreams and flying machines in pieces on the ground." J. Taylor

PM  EMAIL  GALLERY  Attn:RR  Quote
10-23-2013 01:46 PM  4 years agoPost 10
Four Stroker

rrElite Veteran

Atlanta

My Posts: All  Forum  Topic

Consider the liner WORN OUT when it reaches 0.012" gap and replace it. I have ancient clutches with over 1000 flights.

PM  EMAIL  GALLERY  Attn:RR  Quote
10-23-2013 05:37 PM  4 years agoPost 11
meowguy

rrVeteran

Saco, ME

My Posts: All  Forum  Topic

Consider the liner WORN OUT when it reaches 0.012" gap and replace it. I have ancient clutches with over 1000 flights.
My problem is not that it is too loose. Mine is to tight. The clutch grabs at idle. Thanks.

"Sweet dreams and flying machines in pieces on the ground." J. Taylor

PM  EMAIL  GALLERY  Attn:RR  Quote
10-23-2013 06:06 PM  4 years agoPost 12
Four Stroker

rrElite Veteran

Atlanta

My Posts: All  Forum  Topic

jshenck and I understood that. We are saying that 0.008~0.012" is a usable clearance and if you are grabbing you have a cracked clutch OR excessive runout.

PM  EMAIL  GALLERY  Attn:RR  Quote
10-28-2013 10:14 AM  4 years agoPost 13
darren heaver

rrApprentice

rochester, kent, england.

My Posts: All  Forum  Topic

The quick uk clutch is known to have a lower bit point due to the larger heavier shoes. I would wear it in by holding the head and raising the revs slightly but not allowing the clutch to get too hot and it will be fine :-). I match all my clutch shoes and bells by machining on a Lathe and still playing to get the perfect gap so it does not grab too much. I have found that 8-9 thou can still be a bit tight will a quick uk and a lynx gasser clutch. Hope this helps.

" one day I will learn to fly till then I will just hover"

PM  EMAIL  GALLERY  Attn:RR  Quote
11-04-2013 11:27 PM  4 years agoPost 14
meowguy

rrVeteran

Saco, ME

My Posts: All  Forum  Topic

Update on my clutch adjustment...the club in Gorham, ME closed the field last Sunday for the winter, so it was time to strip down this 700 and see what was going on. It was ugly let me tell you. The outside diameter of the clutch shoes was 1.918". The inside diameter of the clutch bell was 1.921. Way, way too tight and no amount of flying it would ever break in that much. So I took it to my local machinist and he took .010 off of the bell (.010 on each side). So it now measures 1.938". Should make a world of difference in getting out to the flight line and stopping at the end of a flight.

The OEM Align 700n clutch shoes measure 1.911, The UK 1.918 Therein lies the problem with the UK Clutch, it's just too big.

"Sweet dreams and flying machines in pieces on the ground." J. Taylor

PM  EMAIL  GALLERY  Attn:RR  Quote
11-05-2013 01:14 PM  4 years agoPost 15
Four Stroker

rrElite Veteran

Atlanta

My Posts: All  Forum  Topic

I hope you meant the the machinist bored out the bell with liner installed to 1.938". This type of thing happens. The Lynx 600N clutch is 0.020" smaller in diameter than the stock Align ? The Align clutch is known to have way too much clearance.

Always measure the clutch diameter on the other side of the flex joint from the shoe tip. You don't want to measure how much the shoes have sprung. If there is much difference in diameter all the way around get a new clutch.

Question: Is the Quick UK 600N clutch heavier than the Align ?

PM  EMAIL  GALLERY  Attn:RR  Quote
11-06-2013 02:15 PM  4 years agoPost 16
meowguy

rrVeteran

Saco, ME

My Posts: All  Forum  Topic

I hope you meant the the machinist bored out the bell with liner installed to 1.938". This type of thing happens. The Lynx 600N clutch is 0.020" smaller in diameter than the stock Align ? The Align clutch is known to have way too much clearance.

Always measure the clutch diameter on the other side of the flex joint from the shoe tip. You don't want to measure how much the shoes have sprung. If there is much difference in diameter all the way around get a new clutch.

Question: Is the Quick UK 600N clutch heavier than the Align ?
Yes, the inside of the clutch bell was turned out with the liner installed. The clutch shoes were measured as you described. When finished, using the now famous electrical tape test, the UK Clutch with a single layer of electrical tape around the shoes, fits nicely inside the bell. The electrical tape is .007" thick. Before the machine work the clutch with tape on it would not go into the bell. Without the tape on the shoes, it slid in with contact inside the bell all around. I did not remove the bell when I changed the clutch last year. This was a big mistake. I see now in retrospect I should have checked the fit off of the bird.

The UK Clutch for the 700 seems much beefier than the Align and it certainly is larger diameter. I only changed mine in the first place last season because I was having so much trouble getting the OWB to grab for starting, otherwise I would have run it stock.

As bad a fit as it was previously, I could still get the machine started and get out to the flight line. It was just such a hassle.

"Sweet dreams and flying machines in pieces on the ground." J. Taylor

PM  EMAIL  GALLERY  Attn:RR  Quote
11-06-2013 04:02 PM  4 years agoPost 17
knightofcarnage

rrElite Veteran

chicago

My Posts: All  Forum  Topic

The UK Clutch for the 700 seems much beefier than the Align
I guess its beefier when it cracks into 2 pices. I had 2 fail the same way. Waste of money. Aligns might stretch over time but i never had one break in pieces. I will try to find a picture of it.

PM  EMAIL  GALLERY  Attn:RR  Quote
11-06-2013 05:25 PM  4 years agoPost 18
meowguy

rrVeteran

Saco, ME

My Posts: All  Forum  Topic

I get the picture. I never would have changed if the OEM had not been giving me fits with starting the motor. You cannot fly if you can't start the thing.

Now that I am finally requiring the shoes to actually open some I will just have to see how long it holds up. Did you perhaps have too much clearance between the bell and shoes?

Thanks for the heads up.

"Sweet dreams and flying machines in pieces on the ground." J. Taylor

PM  EMAIL  GALLERY  Attn:RR  Quote
WATCH
 1 page 2089 views POST REPLY
HomeAircraftHelicopterAlignT-REX 700N › Clutch adjustment on 700n?
 Print TOPIC  Make Suggestion 

 3  Topic Subscribe

Friday, July 20 - 3:57 am - Copyright © 2000-2018 RunRyder   EMAILEnable Cookies

Login Here
 New Subscriptions 
 Buddies Online