Multi part Ship

[Crashonaut]

I've been trying to build a multi part interplanetary ship, yet I can't seem to make it strong enough. when I start a burn it breaks apart at the docking ports. how can I make it stronger?

[3mon]

You mean you are assembling it in orbit? If not, what you need are more struts!

If you are trying to assemble it in orbit, theres not much you can do to add strength to those docking ports... I think there are mods like KAS that allow you to add struts with kerbals on EVA, but havent tested myself...

[celem]

Yes, KAS is the strut-on-eva mod. I find it very effective. And it's probably the best solution, docking ports are very flexy.

Alternatives that dont involve a mod: Very very gentle thrusts, when moving my station I tend to get it moving using rcs thrust (h) before I light the engines (at maybe 4%), just to take the G-shock down a bit.

Look into ion propulsion too perhaps, it will take forever for a big station/craft, but its a non-violent method to start your move.

Also try and keep any docking clamps on the centre of thrust, docks off-centre with more deadweight beyond them causes severe flexing.

Lastly, docking port snr. to snr. seems to be the most solid. Using adaptors to go from thick-body rockets down to regular clamps and then back up to thick again is very wobbly

Remember to disable SAS when moving stations or big multi-part ships (always even, sas and lots of clamps dont mix), it's compensation can often rip you to bits.

Edited November 18, 2013 by celem

[Kasuha]

According to my experience, docking ports themselves are not the weak point but their connection to the rest of the part is. You may try to put some struts between your ports and the part to which they are attached.

Also if you use multiport connections, some ports may not dock, making a weak point.

[celem]

Also if you use multiport connections, some ports may not dock, making a weak point.

Cant find the exact link, but recently saw this mentioned by a staff member. Good point. Multi-point docking doesnt work like you think, the game only actually 'docks' one of the ports regardless, the other connection points may click together but dont get the strength boost.

[Starwhip]

What are you doing with these ports? Lateral connections are usually incredibly strong, but horizontal are fairly weak. And are you using the big, medium, or small ports? If you're using small, forget about it. the medium are iffy, but the big ones you should have no trouble with.

One final note: is your ship *perfectly* symmetrical? If it isn't, your CoT (Center of Thrust) is not going to be inline with your CoM (Center of Mass), and the connections will break.

[DrMonte]

Cant find the exact link, but recently saw this mentioned by a staff member. Good point. Multi-point docking doesnt work like you think, the game only actually 'docks' one of the ports regardless, the other connection points may click together but dont get the strength boost.

I didn't try multidocking myself but saw a lot of videos. It definitely prevents wobbling which in case is the main problem. As you can easily push the ship without docking at all.

Should run some tests on the ground.

[Crashonaut]

assembly in orbit. My ports are always lined up with my CoM and CoT, i'll try with the Sr.s but usually my acc doesn't go over 1 m/s2 and it still flexes and breaks. anyway thanks

[Richy teh space man]

Are you pulling or pushing the payload with your engines? From my experience, pulling a payload is the safest way to move things around.

[Seret]

Can you throw up a screenshot of the vehicle that you're having trouble with Crashonaut? Maybe someone can spot the problem.