How do I create new parts, especially engines, specifically for use in Realism Overhaul?

[Grant Exploit]

The stock of engines and other parts available to me in my build of KSP RSS RO RP-0 (still 1.1.3, can anyone help me out here?) has become boring. Engine mods provide many of the real engines, but more obscure engines (e.g. the HM4, MGM-5 Corporal engine, Wasserfall engine, AJ-260, et cetera) are nowhere to be found, and I want to make fictional engines for my spaceflight-related fictional universes and alternate histories (like engines burning supercooled 100% ethanol and liquid oxygen, hydrofluor, et cetera).

I am also bored of the non-editable historical probes, thermophobic RCS, and the lack of generic heat shields beyond Lunar-rated, though not as much as I am about the engines. 

I have no intention (currently…) to develop mods for other people. I also have no intention to create new models, animations, plumes, or sound effects, just to use those already in existence scaled according to size.

[Phineas Freak]

For existing rocket engines/solid rocket motors you can start by browsing the webz about their physical and mechanical properties (inert/gross mass, diameter, ASL/VAC Isp and Thrust) using the name of the engine. Do not expect a lot of info for very old/not extensively used/experimental engines.

Example for the HM4 engine:

• Inert Mass: 200 Kg (per engine)
• ASL Thrust: N/A
• VAC Thrust: 40 kN (per chamber)
• ASL Isp: N/A
• VAC Isp: 412 s
• Throttle: N/A
• O/F Ratio: 5
• Diameter: ~0.9 m (per nozzle)

You then create Module Manager patches that will clone and convert an existing engine part into your own engine. The MM thread has various examples on how to manipulate the part configs for your own purposes.

For fictional engines, there is only one route: Rocket Propulsion Analysis. You decide what the propellants are, the physical properties of the chamber and nozzle for your application (booster or orbital engine) and it will provide you with the thrust and Isp values. The mass values will be up to you to balance though (can be fudged by using info from other engines with similar properties). Then, you create again an MM patch to make the actual engine part that KSP will use.

Note: all the above are just a quick reference. There are a lot of steps missing (how to setup the engine config, how to clone and convert an engine part config, how to set the actual engine model and scale, how to make plume configs and more). Some of them are documented in the RO wiki (e.g. Adding a Plume to an Engine) but for others you will have to start from existing RO MM configs and work your way up.

Edited August 6, 2017 by Phineas Freak
Typo

[Grant Exploit]

Thanks @Phineas Freak!

[Scotskerb]

I have the same question. With my case, I'm trying to create an engine that, instead of using ignitions, uses electricity. Basically, when you throttle up, it instantaneously consumes an insane amount of energy. After the initial ignition, it generates electricity instead of consuming it. This is a concept of my own where an artificial mini-supernova (mininova?) propels the craft by shooting matter out of the nozzle at relativistic speeds (which, as it may sound, would be extremely efficient).

[Next_Star_Industries]

46 minutes ago, Scotskerb said:

I have the same question. With my case, I'm trying to create an engine that, instead of using ignitions, uses electricity. Basically, when you throttle up, it instantaneously consumes an insane amount of energy. After the initial ignition, it generates electricity instead of consuming it. This is a concept of my own where an artificial mini-supernova (mininova?) propels the craft by shooting matter out of the nozzle at relativistic speeds (which, as it may sound, would be extremely efficient).

 

On 8/4/2017 at 9:15 PM, Grant Exploit said:

The stock of engines and other parts available to me in my build of KSP RSS RO RP-0 (still 1.1.3, can anyone help me out here?) has become boring. Engine mods provide many of the real engines, but more obscure engines (e.g. the HM4, MGM-5 Corporal engine, Wasserfall engine, AJ-260, et cetera) are nowhere to be found, and I want to make fictional engines for my spaceflight-related fictional universes and alternate histories (like engines burning supercooled 100% ethanol and liquid oxygen, hydrofluor, et cetera).

I am also bored of the non-editable historical probes, thermophobic RCS, and the lack of generic heat shields beyond Lunar-rated, though not as much as I am about the engines. 

I have no intention (currently…) to develop mods for other people. I also have no intention to create new models, animations, plumes, or sound effects, just to use those already in existence scaled according to size.

You can do this and lots more with just the config file of an engine.

Edited August 21, 2017 by Next_Star_Industries

[Scotskerb]

1 hour ago, Next_Star_Industries said:

 

You can do this and lots more with just the config file of an engine.

Right, but how? I'm better with planets than parts.

[Next_Star_Industries]

1 hour ago, Scotskerb said:

Right, but how? I'm better with planets than parts.

This will get you started:

https://wiki.kerbalspaceprogram.com/wiki/CFG_File_Documentation

[Benjamin Kerman]

Also just look at other people's config files. It helps a lot if you dont know what something does, seeing it in context can really help.