Securing e-bay to airframe on larger projects...

[threelapfancy]

Hi all. I have a 5" and 6" project going right now. Looking for ways of securing the e-bay to the upper airframe (main will be coming out of the nose)

I have thought about just epoxying nuts to the inside of the e-bay and then securing through the airframe tubing with screws. Another idea I had was cutting pieces of wood, gluing them to the inside of the e-bay and then installing threaded inserts.

I think gluing in nuts would be the easiest and take up the least amount of space, but would like to hear what others are doing.

This is a basic dual deploy set up. The rockets consist of the lower airframe, e-bay between the lower and upper airframe, and then to top it off the nose cone.

Thanks
Steve

 

[uwish]

for my L3, I have screwed right into my top and bottom bulk plates of my electronics bay. I think that is the most secure as I always overbuild my bulk plates.

 

[cobra1336]

I still use those reusable plastic rivets on my 8" Patriot. Have 4 that snap around the airframe

 

[Warthog]

Hi all. I have a 5" and 6" project going right now. Looking for ways of securing the e-bay to the upper airframe (main will be coming out of the nose)

I used to epoxy hex nuts inside my electronics bay and use six #8 screws equally spaced for a 5.38" body tube. But on a few occasions the nuts came loose. I have since replaced them with tee nuts. The tee nuts have more surface area on the flanges for the epoxy to bond to. So far so good. The body of the tee nut was a little too long but I just ground them off flush with the outside of the electronics bay. I also roughen the tee nut flanges so that the epoxy has something to grab.

 

[kramer714]

I use floating nut plates that are attached to the Ebay and countersunk screws. The e-bay slides in place and the screws come in from the outside. Using floating nut plates makes lining things up VERY easy.

The picture shows the E-bay The floating nut plates rivet in place (see the rivet heads on the sides of the hole). The rivets are really small ones just there to hold the plate in place and keep it from spinning. I use the frequently at work, never have them spin out.

https://www.pegasusautoracing.com/bigpicture.asp?RecID=2603 for a picture of a nut plate. I can walk you thru installation if you need, takes me about 2 minutes a nut plate to drill and install one.

 

[TWRackers]

I used threaded inserts into the edges of the e-bay's two bulkheads, and 100-degree flathead screws with countersunk washers through the Dyna-Wind airframe into the inserts. I used my e-bay to join the upper and lower tubes of the airframe, since my main chute was also to come out the top of the rocket. There are pictures of the same hardware attaching my rocket's nose to its payload section in my original build thread here: https://www.rocketryforumarchive.com/showthread.php?t=47306

The screws and washers together protrude very little above the surface, and yet spread the stresses over enough area around the holes that there's little chance of a screw pulling through. The same hardware is used to hold composite panels on the airframes of some aircraft; in fact, I got them from Aircraft Spruce.

 

[Handeman]

On my L2 rocket, I glued a small pieces of oak inside the e-bay. I put enough tape on the e-bay coupler to get a tight fit and two #6 1/2 inch oval head screws go into the oak and hold just fine. Both BTs are attached to the e-bay because I built the fin can zipperless.

On my L1, I used thicker bulkheads on the e-bay, didn't know then what I know now, and just used #6 wood screws directly into the edge of the bulkhead.