AT 24mm RMS ?

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stevem

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I tried to load an E18-4W in my new 24mm RMS casing. When I went to put the grain insulator tube into the casing it went hard. I should have stopped right there but I went ahead and forced it as far as I could. It stopped with about 1/16" still sticking out one end. I could not budge the thing one way or the other. I wound up having to rip it to shreds to get it out of the casing. I had one more reload left so this time I peeled a layer of paper off of the grain insulator tube before I put it in the casing. Much better fit but am I compromising anything by removing layers of paper?

Is this common with these reloads?

Does Aerotech sell just the grain insulator tubes as spare parts?
 
It happens pretty often that I have to take a layer of paper off to get things to fit. Doesn't really seem to effect anything.

Loopy
 
Correct. You have to peal a layer off the liner, and greasing it up helps a lot to. Ask Aerotech for a new liner to replace the one you chewed up.
 
I never grease the liner and have not noticed that in the instructions , what does it do exactly?
 
it's my understanding that it helps keep the outer case temperature down as the grain burns.
 
I don't think it helps with the temperature; in some cases it makes it worse. Read this related article.

Grease makes it easier to get the liner in, and helps prevent the liner from glueing itself to the case after the motor fires. So, it makes it easier to clean the case.
 
It's quite common for 24mm reload grain insulators to be tight. Just peel off a thin layer until it will go in.
 
Hey Steve,
Sorry to hear you had to ruin a reload. I've never had one that tight but close. I do grease my liners also, it sure helps get them out afterwards. The advise on peeling a layer of paper off is just what you do. Hope you find your other lost case also.....Larry
 
n3tjm, I didn't read the question close enough - I thought stymye was referring to the paper tube itself.
sorry for my confusion - its a way of life!
 
yes he's saying grease the liner

...I follow the instuctions provided and do not grease the liner ..I have burned about 30 ,24mm loads and have not had the liner get stuck in the case.. and it greatly increases your chance of getting grease on the grain and ''bonus delay"or "prang" not the best advice for someone new to 24mm reloads. the grease is for the O rings.
If you do grease it ,be very carefull about getting it on anything else

with the bigger cases it might be worthwhile.I haven't tried that either so I can't say.
 
usually it is not a issue getting the grease on the delay element because at that stage of the motor construction, the delay element is already in the forward closure. The propellant is not an issue either because you apply the grease after you insert the grains... and a little grease fingerprint on the propellant won't hurt it. Then when the propellant assembly is in the casing, the insulator ring seperates the propellant section from the delay section. Not an issue.

The only time that the grease becomes an issue is if you have to dismental the motor... then you have a sticky mess.... Thats why I wait till I am sure there is a good chance of having a launch before I load my motors... the grease makes it so much easier...
 
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