Removing waterlogged and stuck motor

[smstachwick]

Two days after splashing down with my Hi-Flier XL, the spent D12-5 motor remains as firmly stuck in the motor mount as ever. Thus far my attempts to remove it have only managed to remove the entire motor mount from the rest of the airframe, and I’d like to avoid damaging the mount if I can. Gripping the spent casing with pliers, either just on one edge or two, has failed to budge it.

So far I’ve left it to dry until the forward centering ring was stiff again. The adapter ring appears to be dry as well.

Is there something I’m missing, a trick to it, perhaps? Could the forward end of the motor still be damp and swollen and I just can’t see it? Is it possible that some of the adhesives holding the paper layers together have leached out and glued the motor to the mount tube and I’ll end up having to cut it/toss it regardless?

I’ve never managed to recover a water landing before so this is all new to me.

 

[neil_w]

This is a difficult situation, without a guaranteed successful outcome.

Try gouging out the nozzle, and then peel the Inner layers of motor casing inward, using pliers.

 

[smstachwick]

This is a difficult situation, without a guaranteed successful outcome.

Try gouging out the nozzle, and then peel the Inner layers of motor casing inward, using pliers.

Alright I’ll give that a go when I get home this evening. The nozzle popped out a while ago, so the rest shouldn’t be prohibitively difficult.

 

[Grant_Edwards]

I removed a pretty securely stuck 18mm engine a while back by chiseling out the nozzle with a screwdriver. Then I used a small file to cut a notch in the inside of the motor casing. As you cut the notch, you can peel out layers of engine's casing with needle-nosed pliers. It's a slow, frustrating, process. Eventually, the engine's casing will be weak enough that you can grab it with pliers, and when you give it a twist it will crumple and come out.

 

[afadeev]

Thus far my attempts to remove it have only managed to remove the entire motor mount from the rest of the airframe, and I’d like to avoid damaging the mount if I can. Gripping the spent casing with pliers, either just on one edge or two, has failed to budge it.
[....]The nozzle popped out a while ago, so the rest shouldn’t be prohibitively difficult.

At this point, I would just go to town on the motor mount tube (MMT) / casing with all the tools you have handy.
Worst case - you damage the MMT, which is very easy to reconstruct. The centering rings should be easy to remove and reuse, and the spare MM tubes should be in every man's inventory (and/or are very inexpensive to obtain from places like www.erockets.biz or www.balsamachining.com)

HTH,
a

 

[smstachwick]

At this point, I would just go to town on the casing with all the tools you have handy.
Worst case - you damage the motor mount tube (MMT), which is very easy to reconstruct. The centering rings should be easy to remove and reuse, and the spare MM tubes should be in every man's inventory (and/or are very inexpensive to obtain from places like www.erockets.biz or www.balsamachining.com)

This will likely be my second option. Thanks for the reality check, motor mounts can be pretty cheap.

 

[heada]

If you let it fully dry, it should shrink and fall out. The drying process can take weeks on an Estes 24mm paper case.

Best thing would be to build a new motor mount.

 

[smstachwick]

If you let it fully dry, it should shrink and fall out. The drying process can take weeks on an Estes 24mm paper case.

Best thing would be to build a new motor mount.

Ick, I don’t have that kind of time. I’m hoping to use up the last of my E12s at Holtville Havoc.

 

[K'Tesh]

+1 with Neil's suggestion

Welcome to the Goldfish Club!!!

 

[kuririn]

I would just build a new mount.
I wonder if compressed paper products , when wet, will return to their original size and strength after drying? I doubt it. Look at particle board after it gets wet. After drying it's still swollen and crumbly.
And much weaker.
I would salvage the engine hook and chuck everything else.
You may even have the rest of the parts in your leftover parts stash. If not they can be purchased quite cheaply. For the engine hook retainer ring you can sub vinyl electrical tape.
For the amount of time spent trying to Macgyver the casing out you could build a new mount in half the time.
As the saying goes, "Penny wise, Pound foolish."

 

[KenECoyote]

I had a few with motors that got stuck since I launch off a frozen lake some winters and sometimes there are puddles. If you get to it quick enough, it's not so bad, but after that the motor swells up. For me what worked was what was said before....chisel/drill out the center stuff, then grab an inside edge of the cardboard with pliers and twist...however I'll add that you should use needle nose pliers and to do a continual rotation to rip and peel away the cardboard from the inside...it's a wind!

If the rest of the rocket has been wet, it may be very hard to restore it. My TLP Maverick landed in a river and I couldn't get to it for 10 minutes...I let everything dry and got the motor out, but later the body tube shrank to the point the nose cone wouldn't fit anymore. I very, very slowly expanded that area using pieces of paper while also jamming the nose cone and it took a very long time to finally get the nose cone to fit. I don't know if it was really worth it. YMMV

 

[Back_at_it]

The Hi Flier XL has those crummy paper centering rings. While unwinding the motor casing is your best option, don't be surprised if the entire mount comes out in your hand.

If that happens, look at i as an opportunity to build it stronger.

 

[smstachwick]

The Hi Flier XL has those crummy paper centering rings. While unwinding the motor casing is your best option, don't be surprised if the entire mount comes out in your hand.

If that happens, look at i as an opportunity to build it stronger.

The mount has already come out of the body tube. I have no intention of making a new one at this time, but I might if the fit turns out to be less than secure.

If the rest of the rocket has been wet, it may be very hard to restore it. My TLP Maverick landed in a river and I couldn't get to it for 10 minutes...I let everything dry and got the motor out, but later the body tube shrank to the point the nose cone wouldn't fit anymore. I very, very slowly expanded that area using pieces of paper while also jamming the nose cone and it took a very long time to finally get the nose cone to fit. I don't know if it was really worth it. YMMV

For what it’s worth, the body tubes have held up to the abuse surprisingly well. By putting the nose back in soon after getting it to shore, it would appear that I’ve headed off the worst of the fitting problems. But I haven’t inspected it particularly closely so I’ll be sure to do that before putting anything back together.

 

[smstachwick]

This is a difficult situation, without a guaranteed successful outcome.

Try gouging out the nozzle, and then peel the Inner layers of motor casing inward, using pliers.

You know how they say that everything leaves a paper trail? Well….

Here’s my trick: with the nozzle already having fallen out, I grabbed about half of the layers at once with a good set of needle-nose pliers. After freeing a ring of layers around the base, I twisted the pliers, almost as if screwing them in. This eventually loosened the next layer, at which point I just pulled, basically disemboweling the thing in one go.

The last layer is paper-thin, easy enough to just grab and pull out of the mount.

I did make one additional repair to the mount by taping the hook down. I had bent it out of the way when I was just trying to muscle the casing out of there, and it didn’t want to go back to being perfectly straight.

I’ll probably end up epoxying the mount back in. The tubes don’t look too bad, and only the centering rings are questionable. One way or another, I’ll definitely find out how suitable they are when Holtville Havoc rolls around.

 

[Ez2cDave]

To be on the safe side, just build a new engine mount.

Dave F.

 

[Ronz Rocketz]

Take sand paper and wrap it around a dowel to get the remainder of the glue out of the BT so the MM slides in easier.

I once had an Exocet in a tree for a couple weeks. It had a baffle and when I pulled the MM out, a bunch of rainwater poured out on my lap that had collected between the motor and the baffle. Yuck...

We have a canal around the park that seems to attract rockets like Charlie Brown kites to a tree. I waded through the canal to retrieve a Patriot. It wasn't worth it.