Not sure how you were planning to make your connections but, if you epoxy the coupler into the extension tube and then attach the extension tube to your booster with Pem-Nuts, you would be able to revert back to your original configuration anytime you wanted to also. Like previously mentioned, watch out for snagging of your drogue, cover the Pem-Nuts with some strips of electrical tape, or build up some tapered transitions around them with JB Weld.
I had considered doing this, but will likely just epoxy the extension in. The weight from it is minimal, and I like the sleek slender look that the extra length gives it. Thanks for the suggestion though.
I was searching for a thread like that, thanks. There's some good ideas and great innuendo in there.
Don't be offended but it doesn't sound like you have built many high power rockets.
There is no need to extend the motor tube. It does not have to be longer than the motor casing. High power rockets do not use a motor block inside the motor tube, so the motor can extend beyond the motor tube. In a high power rocket, the motor has a lip on the aft nozzle flange that prevent the motor from sliding forward thru the motor tube. You should be using positive motor retention so the motor will not kick out when the ejection charge fires. The stock fin can is 31" long and the e-bay coupler is 9" long. Depending on how you configure the e-bay, you should be able to use a motor casing that is ~22" long. That would be an AT RMS 54/2560 (6G) or CTI Pro54-6G case.
This is my first L2 level rocket. I've built a few fiberglass 29mm before, but this is by far the largest most complicated build that I've undertaken, and the first with electronics. As was mentioned below, I'm not extending the motor mount, but the body tube so that I can fit a larger motor in the airframe. For motor retention, I'm using and Aeropack retainer ring.
I didn't read the post as extending the MMT, the OP was asking about extending the bottom or booster airframe tube, indicating that a longer motor would hit the bottom of his E-bay and push it up out of the booster section or just not leave enough room to pack his apogee recovery gear By extending the booster airframe 12" or making a removable additional 12" section for the booster, he will be able to load and fly longer motors into the rocket.
This is exactly the case. As the kit was built, the largest motor I can fit and have room for the drouge and harness is a 4 grain CTI case. I extended it so that I can fit a 6 grain and have room for the recovery equipment.
He may have the 75mm Super Striker.
Nope, this is 54mm. My next will be a 75mm in pursuit of my L3
Thanks everyone for the advice and suggestions. One of the great things about where I live is that Madcow is a half hour drive away. I called them this morning, and they were in the shop and had no problem with me coming down to pick up the pieces. They cut exactly what I needed for me, gave my kids some stickers, and had some great conversation. I can't say enough good things about Madcow, I've never had anything but a great experience dealing with them.
Here is the rocket with the extension already in place, just not epoxied in yet.