Thrust Plate construction issue.

[Ifandbut]

This is a cross post from Reddit because I thought it might more eyes here.

I discovered Thrust Plates the other day and watched Allmhuran's video (

) on the construction. I thought I did everything correctly to make a small plate setup but I keep having the same issue no mater what I do.

https://imgur.com/XvyxkXW

The center tank stack gets a strange physics problem. It appears to not be connected to the decopuler and plate, but at the same time it does not fall right to the ground. When I am launching it with the other tanks in place the center tank bounces up and through all the elements and just looks like it is on a spring.

It appears to happen for outer columns as well. It looks like something changed with the physics and thrust plates are not as stable any more. That, or I am missing something. https://imgur.com/eXmmyTa [3]

I uploaded my craft file to dropbox: https://dl.dropboxusercontent.com/u/30067887/Duna%20Retreival%20-%20Lander%20-%20No%20Mod.craft

I think I removed any mod parts I was using so you should be able to load it into any game. If you go full thrust strait up you will see the outside stack start to bend the i-beams and plates up.

Edited April 16, 2015 by Ifandbut

[Deutherius]

Might be unrelated, but have you tried using a bigger decoupler? I don't think that the TR-2V is designed to handle 42 tons of hanging mass

Also, that video is very old, I seem to recall that thrust plates are obsolete now, at least for that purpose - the radial decouplers + few struts are more than enough to handle big boosters.

[Alshain]

Yeah, that method is obsolete. Just use radial decouplers.

[Ifandbut]

Might be unrelated, but have you tried using a bigger decoupler? I don't think that the TR-2V is designed to handle 42 tons of hanging mass

Same issue but to a smaller extent. It looks like the connection between the decoupler and plate is not sticking completly.

Also, that video is very old, I seem to recall that thrust plates are obsolete now, at least for that purpose - the radial decouplers + few struts are more than enough to handle big boosters.

God damit son of a ...... I'v put 130+hrs into KSP and I FINALLY find a scalable rocket platform that lets me lift crazy things...and it does not work any more. Just my luck.

Yeah, that method is obsolete. Just use radial decouplers.

Which radial decouplers are you talking about? There are at least 3 different versions.

Edit: The cool thing about thrust plates is (as demonstrated in the video) is that you can strut from the lift stage to the payload stage and the struts will remain the whole time. If you just use radical decouplers then as you discard stages you lose stability and could start to "banana" quickly.

Edited April 15, 2015 by Ifandbut

[Alshain]

Which radial decouplers are you talking about? There are at least 3 different versions.

Any of them, it doesn't matter.

Edit: The cool thing about thrust plates is (as demonstrated in the video) is that you can strut from the lift stage to the payload stage and the struts will remain the whole time. If you just use radical decouplers then as you discard stages you lose stability and could start to "banana" quickly.

But then you are carrying more mass throughout the entire flight and worse, in 1.0 it's going to be terrible aerodynamics. As for the payload strutting, I don't see why you wouldn't be able to strut from the payload to the lift stage. I do it all the time. Again, in 1.0 you will be wrapping that payload in a fairing anyway.

I know 1.0 isn't here yet, but you are trying to perfect a skill that is not only obsolete now, but is going to be very obsolete in just a week or two.

[Deutherius]

God damit son of a ...... I'v put 130+hrs into KSP and I FINALLY find a scalable rocket platform that lets me lift crazy things...and it does not work any more. Just my luck.

Well, there are ways to lift crazy things even now... Redirection to Whackjob's starting youtube series, if I may. Not sure if it's what you need, but many crazy things should be expected indeed.

Which radial decouplers are you talking about? There are at least 3 different versions.

I personally like to use the TT-70 most, mainly because of the extra clearance they provide.

"banana"

Haha, banana Anyway, nothing prevents you from putting the elongated structural parts on the payload stage and strutting down to the lifter stage from there. They can even be made disposable by radial decouplers. (Please note that the upcoming KSP 1.0 aerodynamics overhaul will likely end that as well)

[Ifandbut]

As for the payload strutting, I don't see why you wouldn't be able to strut from the payload to the lift stage. I do it all the time.

Dont you have issues when lifting really large odd things? I was thinking of lifting a skeleton of girder segments similar to this picture I saw: http://s3.postimg.org/qwb484o1f/2013_05_28_00004.jpg and I can see that whole segmet going banana as the outer stages fall away just getting it into LKO, let alone Minmus orbit.

Again, in 1.0 you will be wrapping that payload in a fairing anyway.

I know 1.0 isn't here yet, but you are trying to perfect a skill that is not only obsolete now, but is going to be very obsolete in just a week or two.

I didn't realize 1.0 was so close. Maybe I should just shelve everything then and not play until 1.0 is out and mods are updated. If you are right about the aerodynamics then it sounds like 90% of construction techniques will be out of date.

- - - Updated - - -

Well, there are ways to lift crazy things even now... Redirection to Whackjob's starting youtube series, if I may. Not sure if it's what you need, but many crazy things should be expected indeed.

That does not seen physically possible. I figured bypassing the part clipping would cause instant explosions.

[Deutherius]

That does not seen physically possible. I figured bypassing the part clipping would cause instant explosions.

Well, no, they don't, unless you get things wrong and clip the nozzles into other parts completely. That can cause the other parts to overheat and explode.

But I meant the part after 20 minutes, where he demonstrates a real, viable building technique.

[jake9039]

need struts

[Kerbart]

need struts

And boosters. Don't forget the boosters.

[Ifandbut]

But I meant the part after 20 minutes, where he demonstrates a real, viable building technique.

OK, finished the video. That truss cage does look really good. I'm still not sure how to stabilize a payload to prevent the banana but I guess the only answer to that is "struts".

[Alshain]

I didn't realize 1.0 was so close. Maybe I should just shelve everything then and not play until 1.0 is out and mods are updated. If you are right about the aerodynamics then it sounds like 90% of construction techniques will be out of date.

Just to be clear, we don't know the release date, but based on the fact they went to experiamentals most people are guessing that the first week of May will be the absolute latest we see it. But that is just guessing.

[Norcalplanner]

If you're looking to loft heavy loads, there is a trifecta of mods which work extremely well together - SpaceY, Kerbal Joint Reinforcement, and Claw's Stock Bug Fixes. With those three in place you can loft some serious payloads with only a handful of struts. I used these in my Last Hurrah for Stock Aero thread -http://forum.kerbalspaceprogram.com/threads/115629-A-Last-Hurrah-for-Stock-Aero

[cybersol]

I'm just coming back to KSP after a long hiatus, so I can't speak to whether thrust plates are obsolete or not. However, I have used thrust plates on big lifters in the long past, and even then you needed a pair of struts between the top of each tank and plate because the decouplers would sway and break otherwise.

Overall, I imagine they will be less needed due to the larger S3 type parts and engines that were not stock then.

Cheers,

CyberSoul

[Ifandbut]

However, I have used thrust plates on big lifters in the long past, and even then you needed a pair of struts between the top of each tank and plate because the decouplers would sway and break otherwise.

Humm...maybe it is just as simple as adding one strut between the tank and plate. I'll give it a try later.