1 reply to this topic

[GBthriller]

So the other night, I was trying to test a shell. Three times the rocket motors blew the nozzle out. the motors are:

1) E9-4 was stored outside through the winter.
1) E9-4 stored inside.
1) D12-0 stored outside for an extended time.

I feel that it must be something I did to cause three to fail that way, as it has never happened to me before, and I dont know anyone that has ever had that happen either.

The only clues are; we use fuse instead of electric igniters, and we cram a small wad of masking tape in the nozzle to hold the fuse. The tape is wadded sticky side out.

Also worth mentioning; the rockets lift-off normally and about 1/4 to 1/2 second after firing they spit the nozzle. The E9-4's didnt even fire the eject charge upward, saving the shell. Not so with the D12-0, she blew on the ground.

Anyone else have a guess or experience with this? It is very disheartening. You should be able to bank on something in this hobby.

Thanks for the help.

Edit: I hot glue the motors to cat-tails, if thats any clue.

Edited by GBthriller, 28 March 2006 - 10:20 PM.

[Painter]

So the other night, I was trying to test a shell. Three times the rocket motors blew the nozzle out. the motors are:

1) E9-4 was stored outside through the winter.
1) E9-4 stored inside.
1) D12-0 stored outside for an extended time.

I feel that it must be something I did to cause three to fail that way, as it has never happened to me before, and I dont know anyone that has ever had that happen either.

The only clues are; we use fuse instead of electric igniters, and we cram a small wad of masking tape in the nozzle to hold the fuse. The tape is wadded sticky side out.

Also worth mentioning; the rockets lift-off normally and about 1/4 to 1/2 second after firing they spit the nozzle. The E9-4's didnt even fire the eject charge upward, saving the shell. Not so with the D12-0, she blew on the ground.

Anyone else have a guess or experience with this? It is very disheartening. You should be able to bank on something in this hobby.


Thanks for the help.

Edit: I hot glue the motors to cat-tails, if thats any clue.

I've used small Estes rockets without a problem.
I've used Visco and homemade Black Match to light them, but it possibly may be the tape messing you
up!
Try just putting some tissue paper in the nozzle after putting the fuse in.
The stickt tape may be blocking the nozzle too much!
Hope this helps.