Swash leveling: use subtim or adjust links?

[Keratos]

I have read that when leveling the Swashplate, all servo arms should be at 90 deg at midstick, 0deg pitch (throttle curves etc. set) and subtrims at neutral.

Some recommend when adjusting swash level, resize links as needed. But this means the throw of the servo is not equal and it should be.

Others recommend ensuring the links are sized to spec (per manual) then adjust using subtrims, but then this is potentially masking poor mechanical setup and servos would not be at their neutral position at midstick 0 degress.

What is the correct procedure and does anyone know where i can get hold of an underplate swash leveling tool (circular that clips on the shaft under the swash - no need to remove the head)



Thanks

[cjcj1949]

There are different standards that people use. In practice and certainly for learning there is no need to be that fussy. Get the arms as close as you can. The splines stop you getting very close. Then adjust using ordinary trim or subtrim. To get the swash level. When beginning it is important to get the swash level, but many people can get it close enough by eye. It is more important to get someone to test hover and make sure the trim is dead on and no basic mistakes have been made. Also use expo and 70% rates. You have more time than you think when learning. Don't try to hover to begin with, just get it to almost takeoff and get used to the feeling.

[nobbycopter]

I have read that when leveling the Swashplate, all servo arms should be at 90 deg at midstick, 0deg pitch (throttle curves etc. set) and subtrims at neutral.

Some recommend when adjusting swash level, resize links as needed. But this means the throw of the servo is not equal and it should be.

The servo throw will be the same regardless of link length, just because it's longer doesn't mean it will have more movement. This is the method I use, have you seen finless bob's videos on head setup (for the 450 but applies to all FB heads)

Others recommend ensuring the links are sized to spec (per manual) then adjust using subtrims, but then this is potentially masking poor mechanical setup and servos would not be at their neutral position at midstick 0 degress.

The manual lengths should be used as a starting guide. IMO

What is the correct procedure and does anyone know where i can get hold of an underplate swash leveling tool (circular that clips on the shaft under the swash - no need to remove the head)



Thanks

Taking the head off is only one Jesus bolt and undoing 4 ball links on the swash so no real hardship. You can get magnetic ones with mini spirit levels on them, FL do them I know sure all others do too

[Keratos]

EDIT: Just read Neils post.

So Neil, to confirm, servo arms at 90deg/horizontal, then links to manual specs, then adjust swash level using links. Keep subtrims as close to neutral but may need tiny amount of adjustment to compensate for tiny discrepancies in final link adjustments. Also who is "FL" for the magnetic leveler?



So which one is correct, and why?

There are different standards that people use. In practice and certainly for learning there is no need to be that fussy. Get the arms as close as you can. The splines stop you getting very close. Then adjust using ordinary trim or subtrim. To get the swash level. When beginning it is important to get the swash level, but many people can get it close enough by eye. It is more important to get someone to test hover and make sure the trim is dead on and no basic mistakes have been made. Also use expo and 70% rates. You have more time than you think when learning. Don't try to hover to begin with, just get it to almost takeoff and get used to the feeling.

[Keratos]

p.s. I am FBL not FB

[nobbycopter]

Mate...to set up a head you start from the bottom up. Get your servo horns 90 deg or as near as humanly possible, then get the swash to 90 deg by adjusting the links, then move up the head making sure all is at 90deg or level. Then you have to set the servo throws to check for binding etc...after that you'll probably have to adjust the links again to get 90 deg. Might have to doubt a couple of times till it's right.

Watch Finless Bob's video over on the freak, they're excellent!

[nobbycopter]

p.s. I am FBL not FB

Same difference, less links

[jimmyhorns]

I always start at the start, as errors here get more difficult to iron out as you go up. Assuming a flybarred head:

Take off your head, and swashplate.
Set your servo arms to 90 degree to the direction of movement (this isnt always the same as the case of the servo).

Adjust any links from the servo arm to bell crank or equivalent so that the bell crank output arm is at 90 degrees to its direction of travel.

Reconnect your Swash. Level your swash at 0 degrees collective (mid stick, to do this I just set the whole pitch curve to 50%, so that wherever the collective is, its bang on.) You can do this with a swash leveling tool, by eye, or with an allen key cable tied to the main shaft. The important bit is that it is level to the main shaft. The allen key method I have found just as reliable as swash leveling tools.

Check your swash is still level at full positive and full negative pitch, and adjust in transmitter with ATV/travel adjust.

Put on your head. Make sure that your flybar control links are set equally. set the pitch of the blades to 0 degrees with the swashplate centred at 50%.

Double check all bolt tightness, and then you are pretty much done.

It takes about an hour to do all in when you are starting off, and I think its a good habit to get into.

Provided you have the servo arms and bell cranks at 90, the travel of the swash should be equal all round, adjusting links thereafter wont throw your servos out of line.

If you want, you can take a look at finless bobs setup videos. I think they are awful, mostly because he says everything about 12 times and talks really slowly, but usually the basic principles are usually correct.

[jimmyhorns]

Just seen that you are FBL, so the method is good all the way up to after the swash.

[Keratos]

Thanks Neil.
I'm FBL so Finless Bob vid confused me slightly. Although I have downloaded and watched all the vids. Great guy.
I understand now. principles are the same, just less links.

Mate...to set up a head you start from the bottom up. Get your servo horns 90 deg or as near as humanly possible, then get the swash to 90 deg by adjusting the links, then move up the head making sure all is at 90deg or level. Then you have to set the servo throws to check for binding etc...after that you'll probably have to adjust the links again to get 90 deg. Might have to doubt a couple of times till it's right.

Watch Finless Bob's video over on the freak, they're excellent!

[jimmyhorns]

Its always worth remembering that the link lengths in the manual are a starting point, to get you in the right area, and then you adjust from there.

[nobbycopter]

Excellent, you'll find that after you've done it once, crashed, done it again you'll be a master at it

FL was Fast Lad

[Keratos]

Hehe
very good

Excellent, you'll find that after you've done it once, crashed, done it again you'll be a master at it

FL was Fast Lad

[Keratos]

One more supplementary if I can please...
So if check level at 0deg, adjust links etc., then check level at max and min pitch, would i not need to adjust links again and therefore undo the adjustments made at 0deg.
??

[jimmyhorns]

One more supplementary if I can please...
So if check level at 0deg, adjust links etc., then check level at max and min pitch, would i not need to adjust links again and therefore undo the adjustments made at 0deg.
??

The critical adjustment with links is at 0 degrees.

All things being equal and perfect, you would have a level swash at full +ve and full -ve pitch, but it is rarely that simple (though it is on my 600, just by chance (smuglook).

If the full +ve or full -ve are not level, you shouldnt change any of the links, but instead adjust either within the FBL software, or if you had a flybarred head, within the transmitter menus. The exact method will depends on which FBL controller you are using.....