AV Bay - The 1'' band and the internal bands is CA okay then epoxy

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Pyropetepete

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Sorry for the questions but i was always told if you don't know then ask!

I have an ARR Blue Tube 2.0 AV bay in 4'' dia. https://www.alwaysreadyrocketry.com/product/blue-tube-electronic-bays/

I have a 1'' external band to fit on to the coupler. The instructions call for this to be epoxied but i feel this is going to get rather messy quicky. Can i not use some thin CA to fit this band? I'm bolting the air frame both sides with a total of 4 M6 stainless steel bolts ether side (8 total). Align it in place, CA to tack then a ring of CA both sides till it stops sucking it in.

Also the 2 internal rings call to be epoxied inside, 1/4'' from the end (thickness of the bulkhead plate). Again can i not CA these in the apply a filet and use my finger (JC if you see this hope you like) on the back inside of this ring to then make a seal and the strength?

Thanks for putting up with all my silly questions
 
First, epoxying an external band onto a coupler is pretty simple and not that messy. I assume that blue tube is more like a fiberglassed tube and that CA makes for poor joints other than for tacking purposes.

1. Put the vent band on your coupler where you want it to end up.
2. Mark the coupler on both ends of the vent band, tracing the circumference of of the AV bay.
3. Remove vent band. On one side, put a piece of masking tape around the coupler where you marked.
4. Make up a dime-sized blob of 5 min 1:1 epoxy (2-5 gr if you measure).
5. Use a Popsicle stick to smear the epoxy around the coupler between the 2 lines you drew, trying to be a little closer to the one without the tape.
6. Take the vent band and slowly push it on while twisting to spread the epoxy under the entire band. Whatever excess you have will be pushed onto the tape.
7. Wait 2-3 minutes until the epoxy starts to set, remove the tape. You should not have any epoxy on the coupler other than what is holding the vent band on.
8. If you didn't get the tape on straight or you had a runaway while removing the tape, get some acetone or alcohol and wipe off the offending epoxy before it cures (or be prepared to sand or chip it off later).

Second, I am not sure why you are going to bolt both sides of the AV bay to the airframe. Quite possibly you are doing something that isn't going to be an issue but bolting both airframes to the AV bay is a non-traditional design in my world.

Third, If you truly are going to bolt in both airframes in I would agree that you don't have to epoxy the band on. However, CA is a "brittle" non joint-filling glue. Any force applied to the glue joint and it will break, in this case the vent band will separate from the coupler. If the vent band separates there is a possibility that your sampling holes will be covered up. Since applying the band on with epoxy is so easy I would not take that risk, personally.

The same applies for the internal rings - epoxying them in isn't difficult. If you get some glue on the 1/4" of open coupler, just wipe it off with acetone or build up your sanding muscles later. Again, I don't think that you want those to move.

Hope this helps!
 
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CA is not noted for its' sheer strength. using it where sheer strength is needed might not be the best idea. you'll only need about 2g of epoxy(if that) applied to av bay in a thin bead at one edge of the 1" area, then slide the external band in place. cleaning up the excess epoxy is fairly easy with a rag and alcohol, however tis your rocket.
Rex
 
First, epoxying an external band onto a coupler is pretty simple and not that messy. I assume that blue tube is more like a fiberglassed tube and that CA makes for poor joints other than for tacking purposes.

1. Put the vent band on your coupler where you want it to end up.
2. Mark the coupler on both ends of the vent band, tracing the circumference of of the AV bay.
3. Remove vent band. On one side, put a piece of masking tape around the coupler where you marked.
4. Make up a dime-sized blob of 5 min 1:1 epoxy (2-5 gr if you measure).
5. Use a Popsicle stick to smear the epoxy around the coupler between the 2 lines you drew, trying to be a little closer to the one without the tape.
6. Take the vent band and slowly push it on while twisting to spread the epoxy under the entire band. Whatever excess you have will be pushed onto the tape.
7. Wait 2-3 minutes until the epoxy starts to set, remove the tape. You should not have any epoxy on the coupler other than what is holding the vent band on.
8. If you didn't get the tape on straight or you had a runaway while removing the tape, get some acetone or alcohol and wipe off the offending epoxy before it cures (or be prepared to sand or chip it off later).

Second, I am not sure why you are going to bolt both sides of the AV bay to the airframe. Quite possibly you are doing something that isn't going to be an issue but bolting both airframes to the AV bay is a non-traditional design in my world.

Third, If you truly are going to bolt in both airframes in I would agree that you don't have to epoxy the band on. However, CA is a "brittle" non joint-filling glue. Any force applied to the glue joint and it will break, in this case the vent band will separate from the coupler. If the vent band separates there is a possibility that your sampling holes will be covered up. Since applying the band on with epoxy is so easy I would not take that risk, personally.

The same applies for the internal rings - epoxying them in isn't difficult. If you get some glue on the 1/4" of open coupler, just wipe it off with acetone or build up your sanding muscles later. Again, I don't think that you want those to move.

Hope this helps!

I feel a right tool now I've read your steps and it's reminded me a little of how the Loc AV bay tells you to be built. Thank you. I will do this method exactly.

So my AV bay sits in the middle ether side of 2x 20'' long airframes. There is then a booster of 30'' for the motor. Right side is the main and the left is the drouge for example, this is not yet set in stone. Pic here to show

https://i1169.photobucket.com/album...ckets Redliner/dualdeployment_zps6f9bbb00.jpg

These internal rings i will semi apply the same method as above.

Thank you everyone for help on this. Feel so dumb!
 
Gotcha. A picture is worth 1,000 words.

Personally, I like being able to rely on the motor as a backup ejection charge - just don't drill the delay and you at least separate the rocket at some point. A late drogue deployed during descent can prevent a very dangerous lawn dart from an altimeter issue. However, that is just me and there are 1000 different ways of doing this none are better than the other (having lawn darted and realizing how dangerous that can be I'm cautious)

Good luck and don't feel dumb! The only stupid question is the one unasked.
 
Gotcha. A picture is worth 1,000 words.

Personally, I like being able to rely on the motor as a backup ejection charge - just don't drill the delay and you at least separate the rocket at some point. A late drogue deployed during descent can prevent a very dangerous lawn dart from an altimeter issue. However, that is just me and there are 1000 different ways of doing this none are better than the other (having lawn darted and realizing how dangerous that can be I'm cautious)

Good luck and don't feel dumb! The only stupid question is the one unasked.

Thanks for the support and advice. Have printed what you posted on how to do this. Have no laminated it as will use it as a crib sheet with the kids.

So AV band bonding, inner ring bonding, tube marking and drilling then sanding sealer coating.
 
So following jsargevt and as per his title ''Master of the Obvious'' his way worked perfectly!

I made sure i have everything to hand on the table, i took my time and used a stop watch to keep eye on cure time. The AV band went on with no issues. I did panic as it ozzed but i twisted and twisted then did as you said.

The inner AV bands, 1st was not the best but it's in and clean enough. The 2nd i didn't bother with tape this time and once the ring was in gave my finger a good dip in IPA and ran it round, wow never done that before and amazing result! I'm at work now but will post photos once home

Need to drill vent holes now
 
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