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AfterBurners

AfterBurners

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I'm finishing up my SUMO and looking to install a retainer on it. I was considering going with AP, but was looking at the MADCOW retainers. Installation looks relatively easy and they are pretty cheap compared to AP. The rocket is already built, so not sure how much of a hassle it might be to install? I know I should have done it before.The reason I'm considering going this route on this build is because I think it would look better. You know I built the AFT section stock and there's that 1-2" gap from the AFT center ring to the aft end of the MMT. I usually like using the AP retainers when they can butt flush against the AFT center ring. I know it doesn't really matter, but it does look more appealing.


With the MADCOW retainers you have a plate that holds the engine in place and is secured with a couple hex screws and their counter sunk parts.

https://www.madcowrocketry.com/motor-retainer-29mm/

Also if I CATO a rocket with the retainer on I'm not out anything. I can still save the plate and the screws. I know that you can also save the AP retainers. My last rocket that crashed and burned I just cut off the retainer and soaked it in Acetone and it loosen up nicely. There's still some JB Weld on the threaded area that mounts to the MMT, but it can probably be cleaned with a wire wheel on a Dremel.

Anyway just throwing it out there...I know there's a lot of positive retention systems some very simple. Nuts, washers and bolts work well too. I really like the AP retainers, but if I can keep the cost down on some of the smaller builds I will. I think they look great and even better on something that has a boat tail, where you are somewhat limited with what you can use for retention.

Suggestions please ...Thanks!!
 
Last edited:
If you built it per the directions the Estes retainer works perfect and is cheap. You can even install it "under" the engine hook if you put that in there.
 
jsargevt said:
If you built it per the directions the Estes retainer works perfect and is cheap. You can even install it "under" the engine hook if you put that in there.
Click to expand...

I left the hook off. Do they hold up pretty well without melting?? The only thing that I need to consider is the OD on my tube. Not sure what OD the ESTES retainer will fit?? Are they designed for their standard MMT or something thicker??
 
Last edited:
It fit fine on mine.

I have yet to hear of any heat-related issues wth the Estes retainers. The plastic is pretty durable.
 
AfterBurners said:
So it will fit the thicker walled MMT? Did you use it on a Aerotech kit?
Click to expand...

I don't know how I can be any clearer: I installed it on my Sumo and it fit. I can't remember if I had to sand it down or not. If I did have to sand it down it couldn't have been that hard since I am pretty lazy.
 
jsargevt said:
It fit fine on mine.

I have yet to hear of any heat-related issues wth the Estes retainers. The plastic is pretty durable.
Click to expand...

Yes you shouldn't have a problem with heat because there is not any actual contact with hot components. The only thing that is in contact with it would be the aft closure or thrust ring and that doesn't become hot.


Sent from my iPod touch using Rocketry Forum
 
Haven't had a problem with the Madcow (or similar) retainers with AT reloads. However, I am now looking at having to go AP or something different if I am going to start using Loki hardware.
 
conman13 said:
Yes you shouldn't have a problem with heat because there is not any actual contact with hot components. The only thing that is in contact with it would be the aft closure or thrust ring and that doesn't become hot.


Sent from my iPod touch using Rocketry Forum
Click to expand...


The only problem folks have with melting them is if their rocket is too close to the blast plate on the pad. Just make sure it isn't sitting on the plate!


Jerome
 
AfterBurners said:
I'm finishing up my SUMO and looking to install a retainer on it. I was considering going with AP, but was looking at the MADCOW retainers. Installation looks relatively easy and they are pretty cheap compared to AP. The rocket is already built, so not sure how much of a hassle it might be to install? I know I should have done it before.The reason I'm considering going this route on this build is because I think it would look better. You know I built the AFT section stock and there's that 1-2" gap from the AFT center ring to the aft end of the MMT. I usually like using the AP retainers when they can butt flush against the AFT center ring. I know it doesn't really matter, but it does look more appealing.


With the MADCOW retainers you have a plate that holds the engine in place and is secured with a couple hex screws and their counter sunk parts.

https://www.madcowrocketry.com/motor-retainer-29mm/

Also if I CATO a rocket with the retainer on I'm not out anything. I can still save the plate and the screws. I know that you can also save the AP retainers. My last rocket that crashed and burned I just cut off the retainer and soaked it in Acetone and it loosen up nicely. There's still some JB Weld on the threaded area that mounts to the MMT, but it can probably be cleaned with a wire wheel on a Dremel.

Anyway just throwing it out there...I know there's a lot of positive retention systems some very simple. Nuts, washers and bolts work well too. I really like the AP retainers, but if I can keep the cost down on some of the smaller builds I will. I think they look great and even better on something that has a boat tail, where you are somewhat limited with what you can use for retention.

Suggestions please ...Thanks!!
Click to expand...

I like the Aeropack also..have almost the entire fleet outfitted with them.

Pricewise a bitter pill upfront. . but have not been sorry yet. Have started to do estes on estes for 29 and 24mm and do aeropack bases only now to keep the costs down. Also have a couple of caps in the sizes now .

Depending on conditions almost always reaching for the adapter to drop it down..easy - no tape involved.

Kenny
 
AfterBurners said:
I'm finishing up my SUMO and looking to install a retainer on it. I was considering going with AP, but was looking at the MADCOW retainers. Installation looks relatively easy and they are pretty cheap compared to AP. The rocket is already built, so not sure how much of a hassle it might be to install? I know I should have done it before.The reason I'm considering going this route on this build is because I think it would look better. You know I built the AFT section stock and there's that 1-2" gap from the AFT center ring to the aft end of the MMT. I usually like using the AP retainers when they can butt flush against the AFT center ring. I know it doesn't really matter, but it does look more appealing.


With the MADCOW retainers you have a plate that holds the engine in place and is secured with a couple hex screws and their counter sunk parts.

https://www.madcowrocketry.com/motor-retainer-29mm/

Also if I CATO a rocket with the retainer on I'm not out anything. I can still save the plate and the screws. I know that you can also save the AP retainers. My last rocket that crashed and burned I just cut off the retainer and soaked it in Acetone and it loosen up nicely. There's still some JB Weld on the threaded area that mounts to the MMT, but it can probably be cleaned with a wire wheel on a Dremel.

Anyway just throwing it out there...I know there's a lot of positive retention systems some very simple. Nuts, washers and bolts work well too. I really like the AP retainers, but if I can keep the cost down on some of the smaller builds I will. I think they look great and even better on something that has a boat tail, where you are somewhat limited with what you can use for retention.

Suggestions please ...Thanks!!
Click to expand...

If you built it stock I am assuming the motor hook is still attached? I retrofit my single deploy Arreaux, same MMT but a lot less to glue the retainer onto. I used the Aeropack L2 and just sanded a bit off as it's tight or you can use the P model and add a bit of tape 1/4 wide 120 degrees apart. Having said that this retainer on the Arreaux was a mistake because I had nothing to grip onto so I had to sacrifice a pair of old needle nose pliers and bend the tips to use to get into the BT and screw the retainer off an on. Removing the engine hook was another storey but I was able to grind off the forward stop inside the MMT, very carfeully, all the way even with the MMT then I pulled it out and there was almost no damage.

I much prefer the Giant Leap Qwik-Lok Slimline retainer as it has more depth for securing onto the MMT and protrudes out further for an easier grip. I used it on my Arreaux DD, and the only downside is that you need to add a few layers of blue tape about 1/4 inch wide 120 apart as it's a sloppy fit but it is on there really well.

BTW the Demel 80 grit flap wheel fits perfectly down a 29mm MMT and you can use the snake attachment taped to a dowel to get right up there. The only thing you need to do is to remove every 3rd sanding flap, which is pretty easy to do with a sharpe blade. Once this is done it fits down the tube and will clean it right up.
 

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