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AT Mirage Question

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DynaSoar

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I want to build my Mirage with a tail cone and Slimline retainer. To do so, I need to move the fin-locks forward a ways on the motor tube. How much depends on (1) how long my tail cone is and (2) how far the motor tube is recessed from the aft end of the main tube, when it's built stock.

Does anyone out there have a stock built Mirage they can measure for me, and tell me exactly how far the motor tube is recessed?
 

Batman

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I don't have a mirage but why can't you just dry fit the motor mount in stock configuration and measure it?
 

DynaSoar

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Originally posted by Batman
I don't have a mirage but why can't you just dry fit the motor mount in stock configuration and measure it?
Because AT motor mounts include the brackets to hold the fins, and those are enormously difficult to get on the tube. Moving them after is nearly impossible without risking crimping the tube.
 

Initiator001

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Originally posted by DynaSoar
Because AT motor mounts include the brackets to hold the fins, and those are enormously difficult to get on the tube. Moving them after is nearly impossible without risking crimping the tube.
I always sand the inside of the FIN-LOK rings before sliding them on to the motor mount tube. I don't have to worry about crimping the tube and I can slide the rings without concern after doing this.
 

Batman

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Me too. I always sand them so that they are still a snug fit, but not at risk of damaging the motor tube. I always use epoxy on my motor mounts even in AT kits so it shouldn't be a problem to loosen them up a bit.
 

DynaSoar

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Originally posted by jcrocket
End MMT inside BT 11/16"
End of MMT from centering ring 7/8"

Joel. phx

Take an exacto and scrape a bevel into the end of the tube-locks. Light sand inside. Slides on real easy after that. I've used CA on all AT kits (5,.. 6?), but the G-force, which I built as the pre-cursor to my level 1. I'd format a FAQ for AT kits if there were a place to put it.
Thanks Joel.

I hesitate to make the rings slide easily, because they're not supposed to. Part of the engineering of the design was that these were load bearing and so were to be a tight fit. Glue is supposed to keep them in place while the fit carries the load, not serve as a substitute.

There is a place to put something about AT kits: EMRR (rocketreviews.com). Submit a review of their FinLok system in general, or add tips onto the existing reviews for various kits.
 

Stymye

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darn those rings

as long as the ring is in contact with the tube(no gap) it will do the job as designed.. the bottom line is they are way too small and have to be sanded

a crush fit doesn't add anything to the strength

In my line of work, if I made a ring for a customer with that type of fit ...it would be sent back as rejected...a press fit is no more than a couple thousands..even plastic
 
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