How do you stop long rockets from wobbling uncontrollably?

[sekachsiF]

All of this, despite a few thousand bloody struts to hold it straight. For example, built a Saturn V using stockalike parts from the BlueDog mod and it wobbles like mad.

[Jupiter3927]

Turn your SAS off and your wings should keep it stable, assuming you put wings on the bottom.

It really sounds like your reaction wheels are too strong and they're causing a feedback loop of sorts by trying to correct their overcorrections.
Autostrut can help prevent this too but your excessive use of struts already covered that.

[sekachsiF]

But I cannot fully turn SAS off? Only gives pilot or SAS only options, which is a pain.

[Ogre420]

Hope this helps...

In the newest versions of the game high speeds and hard turns in atmo equals crashes.
NOTE: This applies to re-entry also.

For improved stability from launches in Ver. 1.0.+....

Add fins to BOTTOM centerline of EACH stage of your rocket that you expect to be firing below 45k.
(Make sure that they are NOT AIR BLOCKED by fairings or other stuff above.)
Fins on booster stages or fins that are NOT centerline are OK also, but remember that the fins drop off with the boosters.

Turn OFF all thrust vectoring from any firing engine in each stage that is NOT dead center (can be done in VAB)

If you are seeing MACH EFFECTS (The white speed lines around the rocket) throttle back if you can until they disappear.

The nav ball has a flying "V" with a DOT dead center that shows where the rocket is POINTED.
The PROgrade marker (Circle with 3 lines around the outside in a cross pattern) shows where the craft is GOING.
To be safe make sure that the DOT in the flying "V" does NOT go past the ends of those lines on the outside of the PROgrade marker during your grav turn.

SAS and RCS can help keep the craft stable durring the grav turn, extra SAS units can be added (and dropped) with booster stages. If you add RCS JUST for the stability assist during launch, place the monoprop tanks/RCS thrusters where they can be ditched as you reach orbit.

If you are launching with solid rockets as your main boosters around a liquid engine, add a bit more fuel and have the liquid engine firing at low throttle for the thrust vectoring during the SRB's burn.

All rockets and launches are different but as a rule of thumb...
Get to 150 m/s as fast as possible then a slow throttle up to 200 m/s at 10k.
From 10k to 20k a slow throttle up to 350 m/s.
From 20k to 30k a slow throttle up to 500 m/s.
After 30k it's usually safe to floor it and go max throttle.

As you leave the launch pad you will want to start your gravity turn.
If you DIDN'T rotate your control part in the VAB, then that means pressing the "D" key for a zero degree (Equatorial) orbit.

For beginers I suggest a 5 degree turn per 1k meters of altitude until you get to 45 deg. angle.

0k-1k 90 deg. (Straight up . Get to 150 m/s as fast as possible)
1k-2k 85 deg.
2k-3k 80 deg.
3k-4k 75 deg.
4k-5k 70 deg.
5k-6k 65 deg.
6k-7k 60 deg.
7k-8k 55 deg.
8k-9k 50 deg.
9k-10k 45 deg. (200 m/s accelerating to 350 m/s)

At 30k continue turning until the prograde marker is sitting on the horizon line of the nav ball.

NOTE: most people will say that these speeds/altitudes are off, these numbers are just to get you started in the new version, as you gain experiance with the new versions adjust to your own playing style.

[Kletterhase]

i don't know what the community thinks about this (whether this could be considered... uh... cheating... uh... ) but i use the KerbalJointReinforcement mod. No more space noodles :)

[koimeiji]

Originally posted by RoofCatA:

Originally posted by Kletterhase:

i don't know what the community thinks about this (whether this could be considered... uh... cheating... uh... ) but i use the KerbalJointReinforcement mod. No more space noodles :)

isn't that mod slightly redundant since the addition of rigid attachment and autostrut?

KJR stiffens the joints like autostrut/rigid attachment, yeah, but it also slowly ramps up the physics on load along with some launch clamp changes.

So, y'know, when you load your behemoth it doesn't collapse in on itself until after you launch.

KJR also does this all automatically so you don't need to worry about doing it to every part.

[maj.solo]

I dunno ... in what way is it wobbling? Is it the structure that is bending
top and bottom left waist right then
topand botom right waist left
back and forth .... or is it just the rocket tumbling out of control?

[Chibbity]

Originally posted by Roki Vulović:

How do you stop long rockets from wobbling uncontrollably?

I just wear tighter fitting underwear for more support.

[sekachsiF]

How does one enable autostrut? Also have the issue with large modular wings in spaceplanes!

[Jupiter3927]

Autostrut is an advanced tweakable thingy you can enable from the main menu game options.
It's just like struts but doesn't have the same limitations or mass as struts.