This an Issue.??

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Sluggo

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I just finished building a LOC 2.6 Patriot. It looks fantastic though I didn't go all scale with the decals.(see pictures) There is one issue I need to address here.....

Take a look at the fin joints. 2 of the fins, right at the join, are lined up properly. Do not blame the camera angle or anything other than the alignment. Could it be the tube cut-outs are defective.?? I used gridlines in photoshop to make everything straight. You can see the left fin is perfectly straight. The right fin is Not On Plane and glued in just slightly crooked. The joints are off by the thickness of the plywood fin.

Is this okay to fly.?? I noticed the issue right away when I epoxied the fins. I carried on with the build. Comments please..... I love this rocket as is, but......
 

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I've had them worse than that and they fly fine. When I first started building I didn't know what a fin jig was and would glue them on one at a time.
 
The most likely explanation is that the fins aren't quite perpendicular to the body. It will fly fine, go for it.

It's not the fins, it's a bad slotting job. I've seen it on LOC, Madcow, and the worst one was SBR.
 
Yes. Exactly. The slots aren't on the same plane. Thanks Arsenal78.!!
 
A fin guide might have made it noticeable that the slot was mis…..slotted :)

Rocket looks nice , btw

-Bob
 
You are correct. The fins wouldn't fit in the jig. Ding ding.......
 
I have the same rocket with the same issue. Fly it. Mine's been on a G-80 a couple of times.

I will, however, suggest you be diligent with your checks on your center of mass. Mine took a significant amount of weight to be able to fly big G's (or baby H's). If that's not your plan, then disregard. The fins are not very big.
 
You will have to add the larger tube sizes (3", 4" etc)
[/QUOTE]
As was mentioned earlier in the thread..... It's not about fin alignment at all. I too use an angle matte but that solve this this issue. The slots were cut wrong. 2 of the fins are not on the same plane. Understand.?? Its NOT fin alignment.
 
Sorry for the typos. It's not an angle thing so the angle guide you posted will NOT correct the issue. Read the thread and you'll understand.
 
Sorry for the typos. It's not an angle thing so the angle guide you posted will NOT correct the issue. Read the thread and you'll understand.

Fully understood, but if you use the angle guide during assembly, it would have highlighted the problem early enough to address the issue and make necessary modifications.

To answer your original question - no, it will not be an issue. Slight plane offset on two fins will make no difference.
 
It won't help you on this build, but for the future, you may want to get a center finder tool. Very cheap on Amazon. It finds the center of many shapes of objects, but for this application, I always use it when I dry fit everything to make sure things line up. By using this tool and extending the lines down the body tube, you will know immediately if any of the fins slots are in the wrong spot or misaligned. If they are egregiously offset, you can go back to the kit manufacturer to get a new tube before you glue fins in place. You should obviously do this check before you glue the MMT in as well. Later, the marks you make act as additional guides in making sure your fins are straight.

PXL_20201022_024832902.jpg
 
Th
It won't help you on this build, but for the future, you may want to get a center finder tool. Very cheap on Amazon. It finds the center of many shapes of objects, but for this application, I always use it when I dry fit everything to make sure things line up. By using this tool and extending the lines down the body tube, you will know immediately if any of the fins slots are in the wrong spot or misaligned. If they are egregiously offset, you can go back to the kit manufacturer to get a new tube before you glue fins in place. You should obviously do this check before you glue the MMT in as well. Later, the marks you make act as additional guides in making sure your fins are straight.

View attachment 444477
Thanks for that tip. I always dry fit the motor mount tube into the airframe or booster section. LOC uses a company name of..... LOC Precision. Apparently they are not very precise at times. That said, I love their kits.
 
Thanks for that tip. I always dry fit the motor mount tube into the airframe or booster section. LOC uses a company name of..... LOC Precision. Apparently they are not very precise at times. That said, I love their kits.

It is just the law of averages, every once in a while, a tube is going to come out of the slot cutter with something wrong and that is going to happen to every manufacturer. I do love LOC kits as well, but they have taken a lot of heat in the past couple years for shipping some shoddy tubes with their kits.

Regardless of where you get the tube/kit, just check the fin slot alignment. Takes 5 minutes with a simple tool like the center finder and saves you a bunch of potential issues. You really are fine for this build, but if this was a bird you were going to fly with large motors (K and above) or at supersonic speeds, it would be a bigger deal.
 
With rocket kits that come with both airframe and mmt slots for fins, I mark them and spin them around to see which of the three or four (usually) alignments is best. Invariably, one is closest to having all the fins aligned well.

Don't know why it is, just the way I've found them. I'm sure somebody out there probably has an explanation involving the jig the manufacturer uses for cutting slots? Maybe?

Brad
 
Thanks Brad. My experience over the last few weeks has matched yours. I'm noticing now that there is always one fin that isn't 'perfect.' Just the way it is I guess. After reading here I am no longer spooked by it. We'll see how they fly sometime soon I hope.
 
I just finished building a LOC 2.6 Patriot. It looks fantastic though I didn't go all scale with the decals.(see pictures) There is one issue I need to address here.....

Take a look at the fin joints. 2 of the fins, right at the join, are lined up properly. Do not blame the camera angle or anything other than the alignment. Could it be the tube cut-outs are defective.?? I used gridlines in photoshop to make everything straight. You can see the left fin is perfectly straight. The right fin is Not On Plane and glued in just slightly crooked. The joints are off by the thickness of the plywood fin.

Is this okay to fly.?? I noticed the issue right away when I epoxied the fins. I carried on with the build. Comments please..... I love this rocket as is, but......
Guys are right fly fine and yes could be the tube slot..........had this issue with Estes Python...one side of a slot was higher than other.. I guess paper tube flex out differently. Fine.
 
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