Best way to remove a spent RMS liner and o-rings after flight?

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RalPh8

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I got a RMS 29/40-120 casing that I fly G motors on and I consistently have issues trying to remove the spent motor, o rings and liner after the flight. What's the best way to do this? Someone suggested greasing the liner before flight but this didn't make it any easier. Thoughts?

Thank you!
 
Is there a sticker on the liner- if so peel this off.

Grease the liner, grease the case. Push out and clean when still warm.

What grease are you using?
 
Greasing liners is messy so a long time ago I started greasing my cases using spray Superlube. I see on their web page that they have switched to a low VOC version so it may perform differently now.
 
One thing, before you assemble the motor make sure the liner fits in the motor case. Like Mark said, peel off any labels. Sometimes, people have had to peel the outside of the liner to get it to go in.


[emoji1010] Steve Shannon [emoji1010]
 
I use a a THIN layer of Superlube on the liners, and try to remove everything while still warm. As mentioned, usually pushing on the nozzle gets it all the way out. Delay liners can be a little more stubborn and sometimes requires a pair of pliers to get them out.

I've yet to have had a liner stick on me in my 24, 29, or 38mm cases...knock on wood.
 
I cut off a piece of old broom handle about 12-14" long. As long as will fit in my range box. (I use an old drum stick for 24mm). Place the stick vertically on a table, or other solid surface, and place the nozzle against the stick. Push down on the motor, and the casing pops right out.
 
Ok thanks for all the replies. I think my main issue is waiting till it's cold to try and get it out and then I've also not been using the nozzle to try and push it out.
 
Yes as soon as it's cool enough to handle, do it. Also baby wipes for cleaning right after and you'll be reusing boosters faster than Elon Musk!
 
Ok thanks for all the replies. I think my main issue is waiting till it's cold to try and get it out and then I've also not been using the nozzle to try and push it out.

Yep, if you wait until it is completely cool, it will probably take a little more effort to get the liner out. I didn't clean my 29/180 case from yesterday's launch until this morning and I had to get a dowel to force the liner out with the nozzle. Usually they just slide right out.
 
Or if you wait a month like me, you might have to peel it out with a pair of needle nose pliers. Get a little bit pried away from the case insert pliers, then twist and roll the paper liner up on to the pliers.

Other methods are strongly preferred, but when you get lazy . . .
 
I had all sorts of trouble too until I did two things
1) make sure the liner is an easy fit in the case - not super loose, but if it takes any effort at all to slide it in, I peel off layer(s) of carboard until goes in easy.
2) grease the outside of the liner and the sides of the delay well (NOT the end of the delay well)

It all comes out easier still warm, but even cool, things slide out pretty easily using a wooden dowel as long as it is well greased. In the field I try to wipe out the case and delay well with a wet wipe or wet paper towel ASAP after firing.
 
Or if you wait a month like me, you might have to peel it out with a pair of needle nose pliers. Get a little bit pried away from the case insert pliers, then twist and roll the paper liner up on to the pliers.

Other methods are strongly preferred, but when you get lazy . . .

LOL Kevin - brave of you to admit this, I do too as it happens!!! :cool:

I've got one proven and one theoretical method; Proven = get someone else to do it, always cleaner! Theoretical = I reckon one of those handheld steam cleaners would be great for cleaning cases and closures/removing liners etc. Next time we need to clean the oven at home, I'm going to suggest to my wife we get one - then take it out to the shed and try it!
 
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I got out of the hobby before re-loads became as popular as they are now, so I'm spending a lot of time reading the forums and trying build my knowledge level before I purchase my first cases (probably Aerotech at this point). What are y'all using as your preferred high-temp grease?
 
I got out of the hobby before re-loads became as popular as they are now, so I'm spending a lot of time reading the forums and trying build my knowledge level before I purchase my first cases (probably Aerotech at this point). What are y'all using as your preferred high-temp grease?

Super Lube. I think it is what Aerotech includes with their hobby line cases when you buy one new. It only takes a very small amount on the o-rings and liner.

To be honest, there isn't much of a learning curve with reloadable motors. Key points are to lay out all of your parts and follow the instructions each and every time. After you assemble them a few times you'll get the basic routine down, but still use the instructions as a checklist just to make sure nothing is left out.
 
Yeah reloads are easy. AT just need to pay attention to the O-rings. The thicker one is sometimes the forward, sometimes the aft, sometimes they are the same size. Otherwise, they are pretty much the same except the seal disc (longer motors) vs. no seal disc.
 
I found using this board when I first started and even now to be very helpful.
Regretfully, I do no know that they are still available.
Good product for AT or Apogee or someone.
Ken Weaver
29mm-AT-ReloadStation.jpg
 

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Just my experience, but I've found that if it slides easily (not loose) before assembly, it does the same afterwards. Even when I wait a couple of days to clean it.

I have a new cleaning method. Towels called "Scrubs in a Bucket". Water based citrus cleaner on a durable, lightly textured towel. We use them at work to clean adhesives off glass and cars. Easiest cleaning I've ever done.
 
Just my experience, but I've found that if it slides easily (not loose) before assembly, it does the same afterwards. Even when I wait a couple of days to clean it.

I have a new cleaning method. Towels called "Scrubs in a Bucket". Water based citrus cleaner on a durable, lightly textured towel. We use them at work to clean adhesives off glass and cars. Easiest cleaning I've ever done.

Those scrub wipes along with a "ramrod" (just like used in a cannon) that fits the motor casing will allow much easier cleaning in longer cases. I also tend to put as much Super Lube grease (not the dry film) on the liner and case as I can get away with and not get any on the important parts like delays and propellant, usually I push from the nozzle end of the liner (using the nozzle of course) out the forward end of the casing. I also try and do all this just as soon as the motor is cool enough to disassemble.
 
For the removal of O-rings, I use a toothpick. For stubborn liner removal, I will use a wooden dowel that just fits inside the case that will push the liner.

Greg
 
As several others suggested, remove the spent liner and o-rings as soon as it's cool enough to handle. +1 for the baby-wipe suggestion jeff_j_black. I think that works the best too.

A few times, I forgot about it until the next day (or week....) and it was really stuck. A friend suggested throwing the casing in the oven. I put it in at 300 degrees for about 10-15 minutes, then held it with a hot pad and used a dowel rod to push the liner right out. The aluminum expands with heat slightly, which made all the difference.
 
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