A 1/4-20 threaded rod is good to several thousand pounds. You could try putting a stack of large fender washers on a threaded rod, but I don't know how quickly that would add up to 3 pounds.What is the 1/4" rod attached to? How much weight do you need to add? Just off the cuff I'd be concerned about the 1/4" rod snapping under some duress and 1lb weights free falling from that point.
If you're still entertaining ideas, here's a link to a solution that I came up with help from the TRF gang. PM with any questions!HI, I am looking to add weight to nose. does anyone know if someone makes 1lb weights that will screw onto a 1/4" rod. please let me know.
You may want to consider adding the shot to the epoxy first and then pouring into the nosecone. The epoxy coating is more robust that way.I added about 38oz of weight to a 7 12 Hawk by pouring lead shot into the nosecone, then pouring finishing epoxy over that. Next some 2 part foam and a bulkhead. I also added 29mm motor tubing into the foamed area through the bulkhead where I can add some additional weight. The weights also were made of tubing with lead shot epoxied inside. A cover plate and bolt on the bulkhead would hold in place tho I've not flown a smaller motor to need to use that yet.
I've added weight to plastic nosecones in the past. Epoxy generally doesn't stick well to those nosecones, but I did find one that does work well.
1. drill a hole in the base of the nosecone just large enough to drop in ball bearings.
2. add bearings to desired weight.
3. squirt the epoxy into the nosecone to cover the bearings and lock them in.
4. you can leave the hole open if you want in case you want to add more weight in the future.
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