I bought two (2) Lamiglas obsolete blanks at the Orlando Conclave this past fall. GBT 821 H, 6'4", tip 5/32" tight 10, OD .875, pretty of butt. I want to build 2 rods for use with Penn 4/0 electric to fish in 150 to 200 foot max for grouper, spiral or conventional with roller tip. Can someone give me some advice as to a good rod length, I currently use 6'6" Lamiglas C-527, 10"butt and 13" foregrip, and am very happy with the results. But untested in the greater depths and heavier fish. Thanks, Dan

A shorter rod will give the fish less advantage over you. Any load at the tip will be reduced as you shorten the rod. However, you need to be careful that you have enough length to clear the gunwhale and be able to do whatever it is you may need to do with that rod.

I would definitely spiral wrap the rod. This will make it much, much, much easier to fight large fish up from those depths as well as hold the rod while retrieving heavy bottom fishing rigs and weights.

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In the UK we find that longer rods are easier to use (7-8ft) The additional leverage against the angler is minimal and it makes life easier when handling/releasing large fish such as conger eeel at the side of the boat.

here in alaska most of our fishing is at those depth or deeper. the rod length should be pair with the size of the boat.a skiff sixteen or under should be a short rod. the long rods do well on larger boats where one can walk around. as for the roller tip grouper are not that fast to require a roller but to each is own.
C.P.
rod buildewr for 25yrs and alaskan charter capt amd guide for twenty

Actually, the difference in length makes a truly huge difference in the amount of load placed on the angler. For the same load placed on the end of a 6 versus a 7 foot rod, you'll find a noticeble difference in the effort required by the angler. Not that this means that a shorter rod is the ticket for what you want to do, but it's worth considering once you determine where and how you determine you're going to fish the rod.

And, in terms of cushioning shock, a longer rod is usually more capable.

If you want to play with numbers, remember that the load times its distance from the fulcrum (rod butt end) is equal to the effort times its distance from the fulcrum.

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would the fulcrum point be different if the rod were fished from a gimbal or under the arm?

The fulcrum on a fishing rod will be the last point of support. In a gimbal nock, that would be the rod butt end. Stuck in your gut, that would be the rod butt end. Stuck under your arm, it will be the point under your arm where the rod is supported.

Typically, the rod tip moves. The point of effort moves (where you raise and lower the rod with your hand/s). But the rod butt end, stays put/pivots.

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Dan,
You posted you were going to pair the rod with an electric reel? Well, then I guess it's also a big question as to the line weight you plan on using, the drag rpessure of the reel you're going to use, and the max cranking pressure the elctric can produce with said drag pressure. Also, the angle at which the rod will be placed as most of the time when I've seen guys use electric reels, the rod is in a rod holder the entire time. If you don't place the rod more than 90 degrees from the vertical plane, and leave it facing dea into the horizon, I see very littel way the rod will fail unless a big fish nails your bait near the surface and runs under the boat and out the other side with the rod still in the holder at max drag. That's near 180 degree angle depending on the length of rod, etc.! With all things considered and you take care not to abuse the rod too badly when deploying the weight to reach said depths, I think you'll be just fine. I've used 6'6" rods for bottom fishing quite a bit and have had no problems. Cheers!

Dan, I don't do as much salt water fishing as I do river fishing. So I'm not sure how well the following method is known. But on the few times a year when I venture out to the Cook Inlet up here in Alaska, I use Spiderwire and other similar type lines as the first 100 feet of line to minimize drag against the tremendous currents of the inlet, which is supposed to have the fastest currents on earth. That helps me stay with a 6-6 rod and lighter weight, which at depths of 80 or 180 feet, helps in the retrieval process. And the fish we go for go anywhere from 45 pounds to 400.

Patrick Vernacchio