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LOC 5.5" V2

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Bravo52

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Just started working on a LOC 5.5" V2 and am at the point of attaching the fins through the tail cone. There does seem to be a fit problem with the Fins. Logically, I can trim the fin to fit the tail cone by using a scribe. That would make the joint better but might change the geometry a little. The max gap is about 3/16 of an inch, however, the lower tab fits the motor mount square. Again, I have no problem making it pretty, just wondering if I should. Thoughts are the gap might be to allow extra glue in the joint or to keep the right fin profile. What do you think?

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DAllen

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I think the extra gap is because someone at LOC didn't cut the tabs right. ;) IMHO I would think that you'd need to sand the tabs down to get the fin flush with the transition and body tube. I've never seen a manufacturer leave a gap like that for glue purposes that I can recall.

I would find a grinding wheel and grind little bits at a time on the tab until you get a good fit. Heck, give LOC a call and ask whats up with it. I've never dealt with them but they have a reputation of great customer service.

-DAllen
 

Pem Tech

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With the variability between some parts we intentionally leave the TTW fin tabs a bit longer than is needed on our Mid and High power kits. It is up to the builder to sand, grind, carve or chew them down to the right length. With a belt sander you can knock off a bit at a time and keep the proper fin/motor mount alignment.
 

DAllen

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With the variability between some parts we intentionally leave the TTW fin tabs a bit longer than is needed on our Mid and High power kits. It is up to the builder to sand, grind, carve or chew them down to the right length. With a belt sander you can knock off a bit at a time and keep the proper fin/motor mount alignment.
That makes a lot of sense. I would sooo much rather have my fin tabs 1/8" too long rather than 1/16" too short.

-DAllen
 

REAPER

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Just started working on a LOC 5.5" V2 and am at the point of attaching the fins through the tail cone. There does seem to be a fit problem with the Fins. Logically, I can trim the fin to fit the tail cone by using a scribe. That would make the joint better but might change the geometry a little. The max gap is about 3/16 of an inch, however, the lower tab fits the motor mount square. Again, I have no problem making it pretty, just wondering if I should. Thoughts are the gap might be to allow extra glue in the joint or to keep the right fin profile. What do you think?
Bravo52
My 4" LOC V-2 was the same way. I had to modify the fins somewhat anyway because I used a Slimine 38mm retainer on mine. As I recall the instructions said something about there being a gap and just to fill it in with epoxy. Since I was modifying the lower tab to mate to the retainer,I went ahead and worked on the rest of the fin for a better fit. The fit was much better after I was done,but there was still a small gap. Just make sure you rough-up the boat-tail for good adhesion. Good luck on your build!!
 

Bravo52

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This is an awesome kit. I am also using an Aeropac retainer and will modify the lower tab to accept. I am going to go ahead and trim the tabs to improve the fit. Thanks for the inputs.

I'll post a build thread as I am taking pictures along the way.
 

Feckless Counsel

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Bravo52,

Is your plan glue or otherwise attach the lowest, external fin tab to the Aeropack retainer?

Feckless Counsel
 

GRIFFIN

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I had the same issue with my build. I contacted LOC and Barry told me it was designed that way and not to modify it by cutting down the fins. When it was all done, The external fillet filled in the gap with NO problem. I used this rocket for my L2 and have flown it about a dozen times with no issues.

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