Adjustable noseweight

[Reed Goodwin]

I am working on a large project where having adjustable noseweight will be nice, to say the least. I've seen in the past where people will epoxy some all-thread into the tip of the nosecone, and then adjustable weights can be added and then secured with a nut or two on the all-thread. To improve the anchorage strength, a washer can be locked into place on the thread and anchored in the epoxy. My question is about how well the epoxy will hold in the nosecone? I've looked in the archive some and saw some methods for using tubes to fix the weights in place. Can anyone elaborate on these methods?
Thanks,
Reed

 

[troj]

Plastic or fiberglass nosecone?

If it's plastic, it may pop loose at some point. If it's fiberglass, all the nosecones I've seen have more than enough exposed weave on the inside to provide a very solid anchor.

What I do is run a nut on, drop on a washer, then another nut. I adjust the position of the nuts and washer until I can just get the allthread to touch the tip of the nosecone. I then put the nosecone down in a cup of water and pour in enough epoxy to cover all three parts.

This results in allthread that's very securely anchored into the nosecone.

-Kevin

 

[Gillard]

i usually use a reversed bolt that sits into the tip if the nose cone and then use a thread joiner. i glue the bolt into the joiner and attach the other end of the joiner to the treaded bar (without glue). The bolt is then sunk into a bed of epoxy. after the epoxy cures, the threaded bar can be removed easily so extra mass can added. i used penny washers. i i let the epoxy cure with the nosecone resting in a bucket of water.

 

[Reed Goodwin]

Thanks for the tips (hah, hah, hah ). Kevin, It'll be a fiberglass nosecone, but I hadn't considered exposed weave being there, but it makes sense. And thanks for the tip about curing it in a bucket of water!
Reed

 

[Sailorbill]

Here is how I did my 6" fiberglass NC.
Started with a length of 5/16 - 18 all thread slightly longer than the distance from the tip to the aft bulk plate. From the tip it was nut, std washer, nut, space , nut , fender washer, nut, more space, nut, fender washer, 3" bulkplate, std washer, nut.
I prepped the inside of the nose cone I washed it with hot soap and water, rinsed and repeated. When it was dry I poured in some alcohol sloshed it around then dumped it. I did this to remove what looked like mold release on the inside of the cone.
Next I mixed up my epoxy with some kevlar pulp and dumped it in the NC, inserted my all thread, and buried it in the epoxy. I used a bulk plate to keep it centered while curing.
I placed the tip of the NC in a pail of water to keep it cool as the epoxy cured.
I inserted a length of 3" tube and epoxied that to the 3" bulkplate. I used a centering ring in the coupler hold it centered.
When that had setup I pulled the centering ring, applied epoxy and slid it back into the coupler setting it 1/4" in from the aft end of the coupler.
After everything had set up I added a removeable 6" X 1/4" bulkplate held on by a fender washer and eye nut. To prevent the eye nut from turning and possibly detaching from the all thread I drilled a hole through the all thread and installed a hairpin clip.

 

[highpowerrocket]

Check out the nose cone design at https://home.roadrunner.com/~highpowerrocket/. This design works very well for me in 4" diameter rockets.

 

[bsexton]

Check out the nose cone design at https://home.roadrunner.com/~highpowerrocket/. This design works very well for me in 4" diameter rockets.

Interesting design -- I may "borrow" the idea.

 

[highpowerrocket]

Of course, that's why it's out there. Good luck and happy flying.

 

[Stymye]

I usually drill holes into the cone and insert rods/or dowels thru the holes.
when the epoxy sets the load is anchored to the cone....submerging a washer and nuts on the rod makes it even stronger