38mm stuck half way inside motor mount. No what?

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Five

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I got a I175 stuck half way inside my 3in diameter rocket and its not budging in either direction. I tried putting a little Vaseline to ease it in and that didn’t have any effect. Im wonder if it would be safe without damaging the motor to hit it in place with a rubber mallet. Im not even sure if that would set it off. That doesn’t sound like a good idea but Ive tried everything. Any suggestions?
 

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mtnmanak

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I got a I175 stuck half way inside my 3in diameter rocket and its not budging in either direction. I tried putting a little Vaseline to ease it in and that didn’t have any effect. Im wonder if it would be safe without damaging the motor to hit it in place with a rubber mallet. Im not even sure if that would set it off. That doesn’t sound like a good idea but Ive tried everything. Any suggestions?
Take a length of PVC pipe that is a bit longer than the booster section and of a diameter that fits inside the MMT. Feed it from the nose end, turn the whole thing upside down and bang it down on a concrete/paved surface until the motor pops back out. Then figure out why it got stuck and fix the issue.
 

cls

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if you want to try twisting it, get a rubber strap wrench at the auto parts store. (ask for oil filter wrenches.) that happened to me, with a 54/1706, it was stuck for a year but eventually came free! easy does it.
 

Bat-mite

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Hitting it will not light it unless you make sparks. This isn't nitro glycerin. :)
 

boomtube-mk2

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You might try applying one of the low viscosity lubricants WD40, LPS3 etc. around the seem between the motor case and motor tube which might seep down and unstick things.
 

Donnager

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I'd have already graduated to strap wrench (or really large vise grips) and a hammer.

If I could get a good hold on the back of the motor, I'd knock it back. You may need some cloth to prevent gouging the motor case.
 

GlueckAuf

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Take a length of PVC pipe that is a bit longer than the booster section and of a diameter that fits inside the MMT. Feed it from the nose end, turn the whole thing upside down and bang it down on a concrete/paved surface until the motor pops back out. Then figure out why it got stuck and fix the issue.
That's exactly how I've removed stuck lengths of coupler I insert in each end of a rocket being painted so that I can "rotisserie" them between two cardboard boxes horizontally in the paint tent. Sometimes a coupler may get stuck if I've have to build up its diameter with masking tape to make it fit snugly, or if paint has gotten into the seam.

I place a 1/4" plywood tube bulkhead atop the coupler end inside the rocket, then slide in the rod--maybe a stout, 1" dowel or a broomstick handle--and try pushing first against the bulkhead, or up the ante to hammering if that fails. It has always worked to free a stuck tube...eventually.
 

Five

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if you want to try twisting it, get a rubber strap wrench at the auto parts store. (ask for oil filter wrenches.) that happened to me, with a 54/1706, it was stuck for a year but eventually came free! easy does it.
Twisting it helped for about an inch then thats when it really got stuck
 

Five

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I got a rubber mallet and tapped it into place. After I launch it i can stick something through the other end and push it out without damaging it. Now im just worried about the motor sitting in the rocket unattended.
Is that safe. No one smokes in my house so it wont be around any kind of heat. That kinda stuff always has me paranoid though.
 

dvdsnyd

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I got a rubber mallet and tapped it into place. After I launch it i can stick something through the other end and push it out without damaging it. Now im just worried about the motor sitting in the rocket unattended.
Is that safe. No one smokes in my house so it wont be around any kind of heat. That kinda stuff always has me paranoid though.
It will be fine.
 

MJW

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I've never encountered this with a DMS before so this is just a question asked from ignorance... Odds on a CATO for this flight are what?
 

Five

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I've never encountered this with a DMS before so this is just a question asked from ignorance... Odds on a CATO for this flight are what?
Just because you have never encountered it before doesn’t mean its never happened.
 

Five

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Pretty sure the label got bunched up. And then when you twisted it it made it worse. If you just push them straight back out, usually works. Then just scrape off the label.
Thats what had happened on a couple motors in in the past. Probably this one too.
 

MJW

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Just because you have never encountered it before doesn’t mean its never happened.
Absolutely true. That's why I never considered a label that peeled back while loading and clearly stated I was asking out of ignorance. My mind went to a bloated casing instead of a sticky label backing.
 

GlueckAuf

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In the "ounce of prevention" vein, this tendency for motors--especially labeled, single-use motors--to stick in the motor tube is often caused by ejection charge soot from short motors being deposited over time in the top of the motor tube. Forcibly inserting a longer-than-usual motor can then cause a very tight fit, especially, as others here have noted, if the label peels back and wedges itself between tube and motor casing even more tightly.

It's good practice to swab out the motor tube from time to time with a vinegar-dampened paper towel, rag, or even one of Vince's Sham-WOW microfiber towels.

1632928048803.png
 

cls

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Twisting it helped for about an inch then thats when it really got stuck
Ouch! Yeah, I have done that too. Labels on the motor, masking tape, etc.

Don't give up.
 

CoyoteNumber2

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Sort of related - I worked on a group project where the 5-inch by 8-foot casing got stuck halfway in, so we had to repeatedly lift and slam down the rocket to hammer the motor the rest of the way in. Of course this made removal pretty much impossible. Fortunately, the forward end of the motor mount tube had been capped with a bulkhead, so we drilled and tapped it to accept an air hose quick-connect fitting. Then we packed the casing with dry ice to make it contract, and fired up the air compressor. Little by little we worked it loose...until we got to the end, and it shot the rest of the way out like a cannon.
 

Voyager1

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Pretty sure the label got bunched up. And then when you twisted it it made it worse. If you just push them straight back out, usually works. Then just scrape off the label.
Yes, this happened to me once a few years ago with a single use motor. Since then I’ve always removed the labels prior to installing.
 

Ez2cDave

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Shoot video, as you attempt to extract the motor . . . LOL !

Dave F.
 
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