Aerotech Strong Arm - How to remove the spring clip?

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bytesiz

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So I picked up a used Aerotech Strong Arm that was built completely stock with the baffle, thrust ring, and spring clip retention. I'll like to use my 29mm 3G CTI case on this rocket, so I need to remove that crap.

Baffle is easy enough to remove, so is the thrust ring. But how about the spring clip? I can cut the aft end, but I'll need to remove the forward portion as well. Anyone have any ideas or neat tricks to get rid of it?

Assuming I'm able to remove the spring clip, what should I use for retention? I think I coud get an Aeropack retainer on there, but not sure I want to part with the $ for one (the retainer will cost almost as much as I paid for the rocket). Friction fit maybe?
 
So I picked up a used Aerotech Strong Arm that was built completely stock with the baffle, thrust ring, and spring clip retention. I'll like to use my 29mm 3G CTI case on this rocket, so I need to remove that crap.

Baffle is easy enough to remove, so is the thrust ring. But how about the spring clip? I can cut the aft end, but I'll need to remove the forward portion as well. Anyone have any ideas or neat tricks to get rid of it?

Assuming I'm able to remove the spring clip, what should I use for retention? I think I coud get an Aeropack retainer on there, but not sure I want to part with the $ for one (the retainer will cost almost as much as I paid for the rocket). Friction fit maybe?

you can cut a hole in the BT, right above the top of the engine clip and get the clip that way, then patch the hole with fiberglass for cardboard. You can either do that, or spend some time and file it out.
Hopfully,, Upscaler will explain how he did it.

As for the retainer, use a PVC 3/4in Compression fitting, EMRR has a tip on how to do use it.
 
I did had to do the same thing with my arreaux. I just used elbow greese and a small metal saw. It took a while and my elbow was very sore afterwards, but it worked. I put an aropack retainer on mine.
 
Okay, I'd like to try this, but how exactly is it done? I would like to see a picture of motor installed this way.

You're kidding right? Pictures? Just put a piece of tape on the motor,usually near aft end. The more tape the tighter the fit. Use common sense as to how tight you want the motor. It dont have to be so tight that you cant get it back out. I usually go 1/2 to 3/4 wrap, and if I need more, I just double it up.I have flown a Vulcan L750 with just take friction fit.
 
You're kidding right? Pictures? Just put a piece of tape on the motor,usually near aft end. The more tape the tighter the fit. Use common sense as to how tight you want the motor. It dont have to be so tight that you cant get it back out. I usually go 1/2 to 3/4 wrap, and if I need more, I just double it up.I have flown a Vulcan L750 with just take friction fit.

Well, no I'm not kidding. I've never seen it done. But your description seems simple enough. I always presumeed there was some tape over the aft closure and motor tube, but I see this isn't nessesary.
 
Well, no I'm not kidding. I've never seen it done. But your description seems simple enough. I always presumeed there was some tape over the aft closure and motor tube, but I see this isn't nessesary.

jimzcatz is right, just wrap some tape on the motor until it fits tight.

You're also right, you can tape the motors in place. If the motor tube is exposed, a wrap of tape covering the motor tube and the aft closure of the motor will also work. I've use this on my hobbyline cases where the outside of the aft closure is smooth. I don't know how well it would work on the knurled surfaces of the HP closures.

Your best bet might be to friction fit and tape them in.
 
So I picked up a used Aerotech Strong Arm that was built completely stock with the baffle, thrust ring, and spring clip retention. I'll like to use my 29mm 3G CTI case on this rocket, so I need to remove that crap.

Baffle is easy enough to remove, so is the thrust ring. But how about the spring clip? I can cut the aft end, but I'll need to remove the forward portion as well. Anyone have any ideas or neat tricks to get rid of it?

Assuming I'm able to remove the spring clip, what should I use for retention? I think I coud get an Aeropack retainer on there, but not sure I want to part with the $ for one (the retainer will cost almost as much as I paid for the rocket). Friction fit maybe?

Cut a square hole in the body tube above the engine hook, and then simply pull the end of the hook out of the tube, bend it straight with pliers, then seal the hole with cardstock, and re paint it. That's what I did with my Aerotech ARCAS, which I no longer have. As a matter of fact, the reason AKSrockets did such a great job describing it was because I sold that rocket to him :grin:

as for taking out the motor block, put the case in the motor tube, and tap it with a rubber mallet until the motor block gives out. I've done it a couple times...



Braden
 
You're kidding right? Pictures? Just put a piece of tape on the motor,usually near aft end. The more tape the tighter the fit. Use common sense as to how tight you want the motor. It dont have to be so tight that you cant get it back out. I usually go 1/2 to 3/4 wrap, and if I need more, I just double it up.I have flown a Vulcan L750 with just take friction fit.

Jim, I know. It is basic model rocketry 101 (especially for guys like me who were flying them back in the 60's), but now we have a lot of people in the hobby who either:

1. never built anything but modern Estes rockets which all have clips or plastic retainers, or

2. never built model rockets at all, starting with larger modern midpower and high power rockets that all have some sort of active retention.

I see people building and flying rockets that have no concept of some of the basic foundations of the hobby.
 
Jim, I know. It is basic model rocketry 101 (especially for guys like me who were flying them back in the 60's), but now we have a lot of people in the hobby who either:

1. never built anything but modern Estes rockets which all have clips or plastic retainers, or

2. never built model rockets at all, starting with larger modern midpower and high power rockets that all have some sort of active retention.

I see people building and flying rockets that have no concept of some of the basic foundations of the hobby.

Or someone that has only built 2 MPR rockets in their entire life and has gone to a total of 2 lanuches. Did you not have beginners in the 60's?
 
If you want to learn about friction-fitting motors, try the Apogee Blue Streak or Aspire, or the Estes Wizard. The Blue Streak or Wizard will work with the tape around the body tube/motor joint as well.
 
Or someone that has only built 2 MPR rockets in their entire life and has gone to a total of 2 lanuches. Did you not have beginners in the 60's?

Point taken, but I was going by your post count and assumed you weren't that new.
 
Well, that was easy. It took Upscaler's advice and used a dowel ( instead of a motor casing) to tap out the thrust ring. That worked great.. It turned in the tube 90 degrees so I could grab it and pull it out.

The spring clip was cut flush with the aft centering ring with a dremel and a cut off wheel. Then I thought I would use that same dowel and tap on the other part of the spring clip that was up in the motor tube. A couple of good wacks and it broke off at the bend and flush with the tube! Easy!
 
I know this won't help you now, but check on my web site for an engine hook that swings out of the way if you chose not to use it, and allows any length motor to fit.

Andrew
 
Yea, we had begginers back in the 60's. That was people like me and the other gentlemen on this site that are over 50. We burned fingers, learned the hard way so people like some youngsters could learn from our mistakes and not to repeat them.

Most of us old timers have forgotten more about rocketry that some youngsters will ever learn.

Andrew
 
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