CTI Pro29 Stuck

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Moon Knight

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Hey Folks!
I have a 29mm CTI 3 grain casing but I left the last reload in it about a year ago. Now it is stuck. I can’t unscrew it. I tried using pliers with a cloth underneath but I can not get a good grip on the aluminum case. I have not tried pliers on the case, as I do not want to dent it.
Any suggestions?
 
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Can't you just use a wooden dowel ram rod from the fore- end, and use that to clear it out?
 
+1 on the submerge technique mentioned above, it worked well with an Aerotech reload that wouldn't come out when cleaning (24 hours after launch...)
 
Ramming it out is not an option as it is screwewd into the casing.
I think your first post had people confused as to what was stuck, typo said you can unscrew it. Boil to dissolve any gunk stuck in there and a strap wrench as mentioned would be the best bet. Or if you can drill a neat fitting hole that case size in a block of wood and cut it in half you have a handy insert for a vice that can grip without damaging it. Still hold as softly as you can without it turning to be safe and near the far end would be best as it should be more resistant to crushing there.

Sent from my SM-G950F using Tapatalk
 
Soak closure end in small cap of WD40 for a day, works every time.
if it's been a while it may have eaten away at the case.
if it's too late then remember this experience and never repeat it.
 
I think your first post had people confused as to what was stuck, typo said you can unscrew it. Boil to dissolve any gunk stuck in there and a strap wrench as mentioned would be the best bet. Or if you can drill a neat fitting hole that case size in a block of wood and cut it in half you have a handy insert for a vice that can grip without damaging it. Still hold as softly as you can without it turning to be safe and near the far end would be best as it should be more resistant to crushing there.

Sent from my SM-G950F using Tapatalk

Right, the original post said he could unscrew it. If you can't unscrew it, you can also try submerging it in boiling water for 5-10 minutes, and then (using a cloth to handle the metal parts and protect the casing), use a strap wrench or a hands to unscrew it. Some combination of dunking in hot water, dunking in cold water, to get the case and rear closure to expand & contract should work, it will just take patience.
 
Did you get it unstuck yet??????? I'd dig a hole and point motor nozzle towards sky then burn the propellant. Then you could wrestle with the casing and inert rocket burnt crud however you need too. I don't like the fact you got live fuel in it that could ignite and a stuck rear closure.

You could also get a big fuzzy cloth, a bench vice, another cloth for threaded rear closure, and another vice then get a real long cheater bar and apply more torque but do it ultra slowly after the lubricants soak in. More torque works for the most stubborn stuck car bolts real well up until the point you snap the bolt head off, then well more words than I can type are used... If you got brass tools those don't spark.
 
If you have an unused reload in it, I would fly it in the rocket you intended to fly it in last year. I assume the delay was set correct.

After the flight, try to unscrew it again....

If it doesn't come loose then, try Liquid Wrench on the threads. Follow the directions, apply the Liquid Wrench and then lightly tap on the closure with a small hammer. Not enough to damage the closure, but enough to work the Liquid Wrench in. It should unscrew pretty easily.

The reason I know Liquid Wrench works better then WD-40 for loosening things is I watch my neighbor pounding on a pressed in ball joint in his F-150 with a 24 oz hammer. He was using WD-40. When I got back home an hour later he was trying to use a sledge hammer and it still hadn't budged. I took my Liquid Wrench over, squirted it on and began tapping around the ball joint with a 12 oz hammer. By the time I worked around the ball joint two time it fell out of the A-Arm. The stuff is amazing...
 
Had a machine shop class we threaded rods on lathes. The shop foreman had forgotten to run a thread die over the workpiece before threading an actual nut onto it. There was a nut stuck on the threaded workpiece for good we thought. Some other tech emptied and entire can of liquid wrench and that stuff saved the day. PB Blaster is also another brand I've used on stuck suspension bolts on a Volvo.
 
I used the WD-40 soaking method. After a day I still couldn’t get it to budge even with two sets of vise grips. I brought it to my buddy’s place and after looking it over and talking for a bit I picked it up and unscrewed it by hand! Maybe some of the spray worked into the grooves as we held it upside down?
Tomorrow I will work on getting the load and spacers out.
Thanks for the help everyone.
 
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