Thrust ring question

[Anonymous]

Guys, I was wondering if someone with a set of calipers could pull a thrust ring off a 75mm AMW case and give me and OD and an ID of the thrust ring? Additionally, I need the specs on the width of the groove that the rings sits in.

I’m writing because I have a minimum diameter project I’m working on, and I’m trying to order a ring with a reduced width so it will not hang out in the airstream during the boost.

I understand there are a few of these for 54mm floating around in the club… I need the 75mm specs. If I can track some down, I’ll order a few extras.

MANY THANKS

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JW

[Mike Bennett]

Sorry John I don’t have an AMW case to check but I think you may want to clarify what you are asking for since there are a couple of different manufactures that make spring rings with different cross widths in which AMW used at least two different ones and second that you want the OD of the actual spring ring groove and the OD of the ring when it is installed since the ID and OD of the spring ring will change once it is installed hence the name “spring” ring. Just wanted to let you know in case you are trying to do some special motor retention with tight clearances.

[Anonymous]

Mike, indeed you are correct. I talked to the good folks at http://www.smalley.com today and have some samples coming… will keep y’all posted.

I was a bit stunned when all my good work seemed to be for naught as the stock ring hung *way* out into the airstream. One of two things must now transpire:

a.) one of the candidates http://www.smalley.com is sending will work

b.) I have to grind a stock one down

The latter is not good, insomuch as the strength, etc. can be modified. Hopefully something will be in stock and I can use that?

[Mike Bennett]

So what about just taking the thrust ring out totally and doing a bulkhead with all thread and just screw the motor in with a wrap of tape to help hold it in place?

[Anonymous]

Mike, I am using the motor as a coupler 🙂 similar to my H and I rockets (if you have ever seen them up close?) so I can’t do as you suggest…

[Mike Bennett]

Just a thought, but yes…I remember now. Still cleaning dirt out from between the ears if you know what I mean.

[Anonymous]

Mike, I hung around for SPONGE BOB and it was worth the wait! Very, very nice. I’d say it was in the top 1-3 flights of the entire event? JS’s L3 with the M650 was very cool, too… you get extra credit for EX and all those airstarts. Both shots were epic blasts…

[elviss_boy]

Okay, Im guessing you want the thrust ring so your motor doesn’t fly through your rocket. I would suggest taking the thrust ring off, and putting a two inch coupler piece glued in right above the motor so it cant go up and the motor will sit right behind it. With that much service area the motor will stay put.

[SCOTT EVANS]

Mike, I hung around for SPONGE BOB and it was worth the wait! Very, very nice. I’d say it was in the top 1-3 flights of the entire event? JS’s L3 with the M650 was very cool, too… you get extra credit for EX and all those airstarts. Both shots were epic blasts…

YES!!!!!

[Mike Bennett]

Mike, I hung around for SPONGE BOB and it was worth the wait! Very, very nice. I’d say it was in the top 1-3 flights of the entire event? JS’s L3 with the M650 was very cool, too… you get extra credit for EX and all those airstarts. Both shots were epic blasts…

Why thank you John, thanks for sticking around and delaying your trip back home just to watch SB. I was a little more unprepared than I thought so it took a bit longer to prep. My wife kept having to tell me to slow down since I was so nervous.

Good luck on your thrust ring quest.

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