K'Tesh's OpenRocket Tutorials

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I'm designing a rocket that has a nosecone that is larger in diameter than the body tube, so I need standoffs for the launch lugs. I created 2 short trapazoidal fins and positioned them where the launch lugs are, but I can't figure out how to move them up off the body tube to the top of the standoff. What's the trick? o_O
 
I should probably clarify. If your goal is to come with something that really *looks* like the Kraken, you're out of luck. If you just want to simulate its flight characteristics and don't care so much what it looks like, then you can probably get a reasonable approximation but just putting in standard tube fins with length equal to the "average" length of the Kraken tubes.
 
K'Tesh, I'm trying to create a ork file of the Kraken. Making tube fins is easy but how does one alter the shape of a tube fin? Can it be done?

I should probably clarify. If your goal is to come with something that really *looks* like the Kraken, you're out of luck. If you just want to simulate its flight characteristics and don't care so much what it looks like, then you can probably get a reasonable approximation but just putting in standard tube fins with length equal to the "average" length of the Kraken tubes.

Neil is correct. the only thing I could think of would be to "fake" the sloped cuts with a "decal", I was also thinking that if OR could be made to allow for transparent sections to accept decals with transparent sections it could also be faked, but for now... It's not possible.
 
I should probably clarify. If your goal is to come with something that really *looks* like the Kraken, you're out of luck. If you just want to simulate its flight characteristics and don't care so much what it looks like, then you can probably get a reasonable approximation but just putting in standard tube fins with length equal to the "average" length of the Kraken tubes.

Yes, I'm wanting to see the flight sims of the Kraken & not so much the exact look. What's you best guess on the average length? They are 7" long at the body tube and 1.5" at the top. I'm guessing around 2.5" - 3".
 
Yes, I'm wanting to see the flight sims of the Kraken & not so much the exact look. What's you best guess on the average length? They are 7" long at the body tube and 1.5" at the top. I'm guessing around 2.5" - 3".
If you happen to do this sim, try also putting on four sets of three fins, each the shape of the kraken fin seen from the side. I'd be curious how well either method squares with real life.
 
Perhaps it's now a good time to spin the Kraken tangent off into its own thread?
 
Yes, I'm wanting to see the flight sims of the Kraken & not so much the exact look. What's you best guess on the average length? They are 7" long at the body tube and 1.5" at the top. I'm guessing around 2.5" - 3".

I did a build thread of my Kraken some time ago. Snkrl posted a helpful tip that will work for you (Here).
 
Here's a trick that you might help you spice things up... You might call it "folding space". When doing engine mounts, I often want to move the centering rings to be children of the engine tube. However, moving them from the body tube to the motor tube may cause them to shift location (a PITA). By changing their "Position relative to: tip of the nose cone", they're physical location is locked, and I can move the component to whatever parent component I want, and they'll stay put. No more having to move the part back to its proper physical location again.

Oh, and if you turn off "Automatic" OD/ID size options and your workload gets even more reduced, as you won't have to undo those changes in diameter.
 
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Making things easy for yourself... (Why reinvent the wheel... Er... Rocket?)

Ok... I've got an new rocket I'm simulating, and there's a common part from another rocket that I've got on my computer... Can I copy and paste the common part from .ork to the other? In a word... Yes!

When I say copy/paste, I'm referring to the common commands for copying and pasting objects from one file to the next using a PC. I don't have an Apple computer, so I don't know what the commands are for them. With that said... Let's get started.

Here's my new rocket...

1631989985869.png

And my old rocket...

1631990056504.png

The new rocket will have the same nosecone, parachute, shock cord, forward body tube, engine mount, and fins as the old, but not the extra length of body tube as the old. OK... EASY!!! And if you wanted to change the nosecone with another one the steps are practically the same. Copy from the old, and paste into the new. First the nosecone. In the old file, you click only once on it from the menu (you want to highlight it, not open the component window).

1631990392537.png

Now, you have two options, you could click on the Edit menu, or just hit the control (Ctrl) and the "C" keys...

1631990500713.png

Now in the new rocket file, you click on the part it's attached to (in this case, the Sustainer)

1631990643603.png

Then you could go to the "Edit" menu and click "Paste" or just hit the "Ctrl" and the "V" keys to paste it.

(NOTE: I resized the different windows to maximize readability and build area)
1631990812596.png

Now for the rest of the nosecone, I copy (click once to highlight the part, then Ctrl+C) the transition that makes up the rest from the old file...


1631991031661.png

then paste it into the new rocket (click on the parent part, then Ctrl+V).

1631991190978.png

As you can see above, this grabbed everything that was part of that part (in this case the subassembly of the base of the nosecone and the screw eye).
 
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Repeat this process for the body tube you want in the new rocket... Copy and pasting as needed...

Copy...

1631991358270.png


And paste by clicking the "parent" part (in this case the nosecone's Aft Transition Detail)

1631991511016.png

and then Ctrl+V

1631991648062.png

Copy the Engine mount...

1631991702790.png

And paste...

1631991866414.png

Oops...Maybe I should use another engine mount... to delete it, you could do a Ctrl+Z, or click on the part once (to highlight it) and then hit the delete button (or key on your keyboard)...

1631992006568.png

I'll use the one from the Omega instead...

Copy...
1631992161757.png

And paste...
1631992237374.png

Now the fins...
Copy...
1631992294997.png

And paste...
1631992383749.png

Next we'll get the engine hook... (from the Omega)
 
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In this case, we'll copy the PBT from the Omega...

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And paste...
1631992619087.png

From here, you'd want to reposition the engine hook to zero degrees.
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Now you need to fix, or move the launch lug (it was imported from the old file), or add another... Let's move it, and add a second one...

1631993052413.png

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(note: I've moved the paint detail too)
 
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Now, you copy, paste, rename and reposition the forward launch lug... Let's put it at 5/8" down from the top of the body tube.

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Save the rocket now with the name you want, and then you can add your motor configurations, and change your cosmetic details (if desired). Let's look at the new rocket in 3D...
1631993589734.png

It won't win any beauty pageants, but that was not the point... This was for a tutorial...

And... since this spanned several posts... I'll toss a link to the top of this topic.
 

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Another angle on things... (Creating the illusion of edges.)

One of the things that OR regrettably doesn't do is wedge edges on fins. But wouldn't it be nice if it did. What if I told you that you could fake it?

A prime example of this is the Honest John Missile.... Here's what its fins would look like in the average sim... (Mind you this is a work in progress... So, don't freak out about the spin rockets color, location, and shape).

1632754892458.png

The trick is to (if they aren't "broken" already) break the fins into separate parts. In this case, these fins are actually made from two parts, with a joint (barely visible in the image above). You could make them different colors... OR (the easy way) change the level of shine (gloss) on a part of them. The ones above are at Shine: 50% (as is the rest of the sim).

1632755228611.png


Now, let's look at shine at 100%.

1632755577756.png

See... Easy...

BTW, the green I used is RGB 71,90,40.
 
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Color on the inside... Beauty is more than skin deep...

So, you have a rocket where the inside of one (or more) of the body tubes is very visible... Say one with tube fins*...

1635912084462.png

You apply color to the body tube(s) and you get this as a result.

1635912162597.png

Despite using the appearance tab, and selecting the color, you still have the "bare" cardboard appearance on the inside. So, how do we fix this? If you guessed internal body tubes of zero thickness and mass, you're right.

1635912369001.png

After adding your inner tube, set its inner and outer diameter to the diameter of the tube it's going into... in this case 1.595" and its length to the area you want "covered".

1635912556105.png


Now you could try to use an image, or a single color... Let's try the color first...

1635912645321.png

We can copy this and paste it... (I've also renamed it too)(oops... It should be the "Tube Fin's Inner Tube (Black)")

1635912786546.png

Now you could adjust the radial position of the tube you want to be inside the tube fin...

1635912877376.png

and you get this...

1635912991135.png

Now let's try the other tube fin... with an image... (copy, paste, adjust radial position, appearance from file, and you get...

1635913312007.png

And that's how it's done.

*This works with launch lugs too.
 
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