VCP Users

[stevem]

Any of you using VCP I wonder if you can tell me how to enter the CG of a rocket?

It appears that there is a function where you can simply tell VCP where the CG is so you can compare to VCP calculated CP.

 

[quickburst]

I use VCP for every rocket I build. All of mine are scratch built. VCP tells me where the CP is. The bench is for CG, ie .... balancing the actual build.

This is what I do anyway, works for me.

 

[stevem]

thanks David,
yeah that's how I've been doing it - just looks to me like VCP can do this, but I sure could be wrong.

 

[atticus]

If you are in CP/CG CALC MODE (under options) and enter each component's mass and mass distribution (from aft of component) VCP will calculate CG and margin. I don't see how it figures airframe mass, I guess you could enter a mass object figure at its midpoint. You need to enter all internal non-aerodynamic mass items (parachute,MMT, motor, etcetera). Still I would rely on a bench balance. I have built some rockets that came out much heavier in actuality than rocksims figures (I tend to overdo on MMT adhesive, fillets and paint.)

If rocket is built and loaded, you can enter a single mass object at your determined balance point in CP/CG SPEC MODE and indivual aerodynamic mass figures are ignored.

 

[jjnodice]

Originally posted by ATTICUS
If rocket is built and loaded, you can enter a single mass object at your determined balance point in CP/CG SPEC MODE and indivual aerodynamic mass figures are ignored.

That's how I have done it also. Works well!

VCP is a member of this forum. Perhaps he'll see this thread or you can PM him.

Jason

 

[vcp]

Originally posted by ATTICUS
If rocket is built and loaded, you can enter a single mass object at your determined balance point in CP/CG SPEC MODE and indivual aerodynamic mass figures are ignored.

Sounds good to me. I know its sad, but I'm probably the last person to tell you how to operate it; I've rarly even started it up in the past few years.

GC