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I have a can of silicon spray I use, just give it a squirt down the tube and everything goes in pretty easy. One thing I learned long ago is don't push on the nozzle to get the motor in the last few inches. Use a spacer! Two failures I have attributed to pushing on the nozzle:
110.jpg

144.jpg
 
Per the directions.....

"The o-rings are pre-lubricated at the factory, but we recommended that you apply a light film of silicone o-ring lubricant to the inside edge of the motor casing
where the reload kit will be inserted. This will make installation and removal of the reload kit much easier!"

I also use silicone spray as it then slides easily.
 
Wayco said:
I have a can of silicon spray I use, just give it a squirt down the tube and everything goes in pretty easy. One thing I learned long ago is don't push on the nozzle to get the motor in the last few inches. Use a spacer! :/QUOTE]

+1 on this. The silicon spray is very useful, especially on bigger motors. Somewhere I remember CTI recommending this. Definitely helps get the big motor in the casing. If you have to push, use the spacers.

On a slightly different topic, I am thinking that an L935 in a Punisher that wasn't overbuilt might be testing the waiver for TCC.
Click to expand...
 
Speaking of O-rings; What size does it come with?
The ones that came with mine are tiny

I just put one together, that was from late 2009.
I see there are 2 sets of o-ring grooves on the nozzle and forward closure.
My best guess is; this so they can use the closures and nozzles for different hardware.


I hope to fly this motor in my 3.0" Wildman DD at LDRS.


JD
 
JDcluster said:
Speaking of O-rings; What size does it come with?
The ones that came with mine are tiny

I just put one together, that was from late 2009.
I see there are 2 sets of o-ring grooves on the nozzle and forward closure.
My best guess is; this so they can use the closures and nozzles for different hardware.


I hope to fly this motor in my 3.0" Wildman DD at LDRS.


JD
Click to expand...

Hi JD,

Mine is sealed up and I'm heading out of town in an hour or so. I will check when I get back in about two weeks if no one else gets back to you. Thanks.
 
4kids49 said:
CJ hit 12,668 ft on a CTI K815 skid in Australia. 14 k might be doable with an L935 depending on your build.
Click to expand...

Yikes! My 9800 feet observed is way off. I will try to verify via GPS but I definitely had a ton of arcing after what looked like trans sonic wiggle. I might rebuild the front end a little longer if I try a motor this crazy again.

For the record, I left all grains concave side forward, flat side aft, and the motor appeared to work perfectly. It was an amazing sight even if I did not get the altitude I wanted.
 
watermelonman said:
Yikes! My 9800 feet observed is way off. I will try to verify via GPS but I definitely had a ton of arcing after what looked like trans sonic wiggle. I might rebuild the front end a little longer if I try a motor this crazy again.

For the record, I left all grains concave side forward, flat side aft, and the motor appeared to work perfectly. It was an amazing sight even if I did not get the altitude I wanted.
Click to expand...

Congratulations. You sent up an awesome rocket on an awesome motor.
 
The ROC guys had a drag race last weekend using Punishers and a K1440. The guys that added ballast and used tailcone retainers got the highest altitudes. To me it sounds like yours could probably use some nose weight over added length. Unfortunately I didn't arrive early enough to see your flight.
 
I was so excited about flying and getting the video back I completely forgot to remove the spent reload from the case. Now it is totally stuck.

Any advice or tips? The nozzle was no problem, and the forward plug has some play, but the liner does not budge. Would acetone make it better or worse?
 
I have an 18" wooden dowel that fits snugly into the top of the forward plug. I hold the casing in one hand and the dowel in the other, then pound them into the cement floor. Once it starts moving, you can usually push it out with a longer dowel. Wear gloves! It takes some skill to keep everything aligned, but this works for me.
Did you grease the liner? If you didn't do that, better start looking for a new case....
 
Wayco said:
I have an 18" wooden dowel that fits snugly into the top of the forward plug. I hold the casing in one hand and the dowel in the other, then pound them into the cement floor. Once it starts moving, you can usually push it out with a longer dowel. Wear gloves! It takes some skill to keep everything aligned, but this works for me.
Did you grease the liner? If you didn't do that, better start looking for a new case....
Click to expand...

+1 ^
 
I did grease. My 54mm5G burn came out no problem, but this is something else entirely. I am bashing the whole assembly on concrete, plug end first, and no movement yet. Yikes! I would think there is some kind of solvent or tool to help, but it could be a lost cause. Or, maybe it comes out, if I simply keep trying.
 
watermelonman said:
I did grease. My 54mm5G burn came out no problem, but this is something else entirely. I am bashing the whole assembly on concrete, plug end first, and no movement yet. Yikes! I would think there is some kind of solvent or tool to help, but it could be a lost cause. Or, maybe it comes out, if I simply keep trying.
Click to expand...

there is no such thing as a "lost cause" when it come to this. You can heat the thing back up to the same state it was in when the motor had just burned. I would get a thick wooden rod (just thinner then the forward opening) and with brute force strength, pound that sucker out. If you give up, send it to me before you send it off to waste management......I'll get it!!! If you are going to LDRS, bring it there C/J will be there and he can give you some guidance and most likely even has a "beater stick"
 
GRIFFIN said:
there is no such thing as a "lost cause" when it come to this. You can heat the thing back up to the same state it was in when the motor had just burned. I would get a thick wooden rod (just thinner then the forward opening) and with brute force strength, pound that sucker out. If you give up, send it to me before you send it off to waste management......I'll get it!!! If you are going to LDRS, bring it there C/J will be there and he can give you some guidance and most likely even has a "beater stick"
Click to expand...

Now that you mention it, I have a heat gun at the office. Thanks for the encouragement!
 
JDcluster said:
Speaking of O-rings; What size does it come with?
The ones that came with mine are tiny

I just put one together, that was from late 2009.
I see there are 2 sets of o-ring grooves on the nozzle and forward closure.
My best guess is; this so they can use the closures and nozzles for different hardware.


I hope to fly this motor in my 3.0" Wildman DD at LDRS.


JD
Click to expand...

Hi JD,

I looked at the plugged forward end of an opened L1030 that I have. The most forward groove did not have and O-ring, and looked to be made for a thicker O-Ring. The more aft groove (second groove from forward end) was narrower and had a much narrower O-Ring in it. I will pull out the whole motor and can try to measure it tomorrow. I hope that this helps.
 
To the original post:

1) It IS! Fantastic motor--one of those, afterward, where it's like: "Wait.. that was a 54?"
2) Flat back, concave forward. When the propellant lights, the flame is to ignite the core as well as the grain ends--so they burn from the inside out, as well as from the ends in. The equal concave fronts on each grain provide identical surface area for burning on each grain, where a flat-on-flat will not, as you'll get areas of low flame (flat on flat), and high flame (concave on concave)... which might lead to boomage. The grain closest to the nozzle uses the nozzle's concave front for its aft end.
3) The "forward closure" on these is the same as the rest of the small CTI line: plastic housing set into the liner, which mates up with the rolled end of the casing. This is a plugged motor. Regarding threading/threaded forward closures in 54mm... this thread: https://www.rocketryforum.com/showthread.php?69010-CTI-54mm-Tapped-forward-closure-question covers it pretty well.
4) Silicone spray.


Later!

--Coop
 
I flew this motor at LDRS and it was spectacular!
The only problem; it was not recovered :(

JD
 

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