Ground Charge Testing

[cdma77]

When you test your rocket for the proper BP charge size do you guys just aim to blow the nose cone off or is your goal to blow the whole parachute out with the noze cone ?

Thanks,

Jeff

 

[Johnnie]

The charge must empty the body tube. It does not have to run to the extents of the shock cord, but the chute must eject when testing.

 

[Rocketmaniac]

Along the same lines.... Is there a program, chart or formula to figure out the right size of ejection charge to use?

 

[wyldbill]

Using Estes igniters is lot cheaper for this than e-matches. Save your matches for flight or maybe a final test. Run your launch controller through a vent port and connect to the back side of your charge holder.

 

[cdma77]

Originally posted by wyldbill
Using Estes igniters is lot cheaper for this than e-matches. Save your matches for flight or maybe a final test. Run your launch controller through a vent port and connect to the back side of your charge holder.

I don't use e-matches for testing. I use x-mass bulbs with the tops cut off. I glue straws on and fill with BP as needed.

 

[bobkrech]

The purpose of a ground test is to test the entire recovery system as it will be flown to insure it will work when flown.

If you are going to use an e-match in flight, then you should use an e-match in your ground test.

Saving a dollar or two is not worth it compared to a several hundred dollar rocket.

Bob Krech

 

[cdma77]

Originally posted by bobkrech
The purpose of a ground test is to test the entire recovery system as it will be flown to insure it will work when flown.

If you are going to use an e-match in flight, then you should use an e-match in your ground test.

Saving a dollar or two is not worth it compared to a several hundred dollar rocket.

Bob Krech

Bob,

I only use the lightbulb charge to "zero" in on the charge size. Once I have the proper size I test it with an e-match. Again, test with something inexpensive, verify with an Oxral and fly with an Oxral !

Jeff