I have been using a 7/16” cold roll rod system that I made for many many years, and I am very happy with them; however, I am always willing to try something new, and I bought some fiberglass rods. I am going to make some kind of top end and bottom stop for them. I have a full machine shop, so if it can be made with a lathe, knee mill, welding, etc, I can make it.
I do have a few ideas of ways to do it, but wondering if anyone else has any slick ways that worked well, or even principles to share. Like how much pressure can the rods take before they crush, how well do they stand being drilled through the rod (like for a pin), can I put the rod in a lathe and drill into the end of the rod and thread it, that kind of stuff. I guess I just have never messed with much fiberglass in general, and never messed with these rods at all. They are the good rods from Minnesota if that helps (seems like they were sold as Geotek rods?).
Basically I am looking for any advice or tips on making the top end hardware and working with the fiberglass rods.
I have seen the commercially available ends, but I want to make my own.
Thanks for any help.

I use rebar and fiberglass. On the rebar, I slip a nut on the end and weld in place and on the top, weld the nut so a T-bar can be slipped through to secure the top.

Simplest I can think of is a couple ss screw clamps over a loop of cable for the top, and another clamp or two for the bottom to stop your slider....

Simplest thing is to just buy the hagz system.

I have experimented with threading the rods. Just not sure how well the threads will hold up over time.

My rods from Rally just have a wire loop wrapped on top and a stop screw at the bottom.

Another thing you can do is weld your attachment points to a piece of conduit then slip that over the rod and smash bind the conduit onto rod

X2

X2 Hagz system.

That's what I have. Like them better than metal rods.

Thanks for the advice. Of course the simplest is to buy the hagz system! But I enjoy making my own stuff. I even stated that I was aware of the commercially available ends, but I wanted to make my own.
Just for the record, the hagz ends are top quality equipment and well done, and if I did not have a machine shop I would definitely buy the hagz!
What I am looking for is advice/information on how others have made their own hardware, and the properties of the fiberglass rods in general so I have an idea of “what I can get away with” doing to the rods.

With your resources, I'd make sleeves out of thick (stainless if you have it) pipe that just fit the rods and put a couple set screws on the side of each weld a ring on the end of one, leave the other as is for the bottom. You could also put a T on the end of some and cut your rebar shorter and install the T to hold the top of the drowner. You could also use epoxy on them for added insurance if you never intend to take them apart.

Not an answer to your question, but a bit of caution: don't run a bare hand down the fiberglass rod. I used the green fiberglass rods from Home Depot and had slivers of fiberglass in my hand.

I like that idea on the set screws. Thanks ADC. I also had thoughts of drilling the rod and putting pins or macine screws through. But I have no idea ho the fiberglass will react to drilling.

I'd loc-tite those set screws for sure.

We're those the concrete reinforcement fiberglass rods? I don't think those have have the coating that prevents thatoke on regular fiberglass rods. Even the regular rods will get that if you're beating them in with a hammer.

All those FB rods break down in the sun and give splinters.

my white ones have shown no sign of breaking down.