Rocksim Sub-Assemblies

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Well-Known Member
Jan 17, 2009
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Has anyone worked with sub-assemblies in Rocksim? It seems like a very cool but under utilized feature of Rocksim. After reading the Apogee Newsletter #118, I wanted to try my hand at creating a useable sub-assembly. Here is my first effort. It represents the Fliskit EMK3-24-70R cluster motor mount. I incorporated a number of Fliskits parts into the Rocksim parts database as part of this exercise. Let me know what you think.
Here is the sub-assembly file.

(Please note, TRF only permits certain file extensions to be uploaded. Please rename EMK3-24-70R.RSA.TXT to just EMK3-24-70R.RSA)
Here's a Rocksim sub-assembly for the Fliskits EMK3-24-70 (with the BT-69 sleeve tube.)

Note: BT-69 was added to Rocksim parts database.
Here is the EMK3-24-70 sub-assembly file.

(Please note, TRF only permits certain file extensions to be uploaded. Please rename EMK3-24-70.RSA.TXT to just EMK3-24-70.RSA)
After getting the hang of it, sub-assembly files make designing so much easier. Lately, I spend more time making the subs than full rocket designs. ;)
These look good, why not send them to Jim Flis so he can put them up on his website!

BTW; Are the weights correct for these sub assemblies, 25.5 grams for EMK3-24-70 and 23 grams for EMK3-24-70?

Bruce S. Levison, NAR #69055

Thanks! That means alot coming from you! The weights are close, but do not exactly match those posted on the Fliskit web site. All other dimensions were taken directly from this source. I tried the mass override option, but you then also need to supply parts CG manually.

I need to update the materials data base to include details on fiber parts (i.e. centering rings), as well as, multiple paper densities. I believe Rocksim is using this information to automatically calculate the parts mass.

After developing these 2 sub-assemblies as a self teaching exercise, I thought there may be some interest from the many smaller kit manufacturers to have both their parts and parts kits (i.e. cluster mounts) available within Rocksim.
That would be an idea for the next version update, perhaps a bank of standard assemblies used by a large number of designs, for example "standard construction" 18-24 mm motor mounts (BT-20 inside BT-50), 24-29 mm mounts, etc etc., standard chute and shock cord mounts (lol... the never-ending debate of Kevlar vs. Elastic... ;) )

I know of course there is variation on how everyone builds their mounts, but not very much, it would be cool to just be able to click on a file "18-24 Mount" and bingo, it's in the rocket. Oh well, guess I'll just keep hacking away at my own subassembly library...