AT 54mm ejection charge question.

Hello

At my last club launch there seemed to be some different opinions on this so I thought I would post here for some advice. Does the standard ejection charge that comes with a AT 54mm J540R have enough black powder to reliably open a rocket with a 7.6 inch diameter like the LOC Bruiser for example? Some said it should be no problem others were saying that if you didn't add some more black powder it would be at risk of not coming apart. So what does everyone here think?

Thanks in advance

No, I don't think the standard amount supplied by AT would be enough. Especially for a kit like the LOC Bruiser, that is a lot of large diameter tubing that would need to be pressurized. I would think you'd need to add at least a couple grams of FFFFg powder to be 100% sure it's enough for reliable ejection/separation. I would definitely ground test to make sure you get a large enough amount in there; that would be a mighty big, bad lawn dart if the amount wasn't enough. :/

-Joe

Depends on how much internal area you have to actually pressurize. I used to do this alot, and what I did is before you put the paper disk on(I would can the big red plastic cap) wrap some 1 inch tape around the knurled end, fill with BP and pinch the tape closed. Worked every time.

Depends on how large of a compartment you have. Ground testing would be a good idea if you're not sure...


Later!

--Coop

Coop said:

Depends on how large of a compartment you have. Ground testing would be a good idea if you're not sure...


Later!

--Coop

Click to expand...

How would you go about ground testing a motor deployment charge...?

Plug up the motor tube with a casing. Make a charge equal to the published amount for that particular motor, and see if it works. Adjust as necessary.


Later!

--Coop

Spicer007 said:

How would you go about ground testing a motor deployment charge...?

Click to expand...

Parts needed for ground testing motor deployment charge.
1: Black powder
2: quest motor starters
3: rubber glove or sandwich bag
4: at least 15' of power wire
5: a 9 volt battery
First cut off a finger tip of the glove or corner of sandwich bag, measure out BP and put in glove tip or sandwich bag corner, put in the quest motor starter and tape it all together so no BP falls out, prepare rocket for launch and put empty motor case in to motor mount. This rocket will have a 1/8" vent hole which you can run the 15' power wire through and hook up the separation charge
When ready touch battery to the power wire.
I hope this helps, if you need photos I can post them for you