I wanted to run a question by the pros on this board. I have the opportunity to build on a pretty unique S-glass blank for crankbaits and spinnerbaits. It's extremely light and the action is moderate yet strong. I will be building it with Fuji Concept Alconites spiral wrapped. I've been reading alot about blank construction and the effective spine. My question is this. Would it make sense to build this rod with the effective spine down towards the water instead of on top. My thinking is this. With the spine down it would lend power to the cast. The rod would be inherently stable under load due to the SW so I'm not worried about torsional problems. It's going to be a bass rod so fish fighting is not an issue either. So with this being a moderate action blank I figure by buidling with spine down it will lend power to the cast. Any thoughts on this?

The spine cannot lend any additional power to the cast, the spine is the least powerful axis and the opposite of the spine, is NOT the most powerful axis. These two axis's can vary between 45 to 170 degrees apart. On occasion, they are opposite, but only rarely.

But putting the spine on the bottom will help the rod track better on the forward cast and as you say, the spiral wrap will keep the rod stable both on the backcast and while under load. That position is highly favored by many builders and I would be surprised if you did not like it.

I do want to add that strength is always the same regardless of where you put the spine. Stiffness, of course, can vary a bit depending upon the particular plane the rod is in, but overall strenth is the same no matter what.

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Tom, I guess I did understand that but again use the wrong choice of words. I think that is the one problem in our craft I find difficult putting the right words on descriptions. In this case power being relative to increased casting distance and efficency. To clarify, the blank will naturally, under load try to rotate to where the spine is on top, like it would in a spine finder. This natural rotation is why under heavy fish fighting loads it's better to put the spine on top. But with the SW this natural rotation is easily overcome because the rod is dynamically stable under load. So if we put the spine on the bottom this natural state the blank wants to be in would work to our advantage in the cast being stable in the backcast and and not necesarily a hidrence in for forecast due to the weight of the guides. Did I say that right?

Yes, but you still must understand that the line also seeks the direction of load on the backcast and once again the spine is easily overcome and the rod will try to twist in that scenario as well. Thus, the idea is to use the lowest frame guides possible near the mid and tip areas to reduce this torque effect as much as possible and allow the rod to track without twisting, if possible.

Most of the time, with the spine on the bottom and the use of low frame guides and the fact that the rod is not heavily loaded on the cast, you can get by with this placement and achieve good tracking on the cast.

One last thing to consider - put the rod/reel set-up in your hand as if you were preparing to cast it. Do you rotate your wrist at all? If so, you may want to locate spine in that axis, and not simply on the bottom of where the rod will be oriented when fishing.

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I turn my hand almost 90 degrees when I cast which puts the reel's handle pointing UP. So I put my spine in that axis so the rod tracks during the cast. I really like the way it performs. I always use a spiral wrap so rod twist is not a concern.

Thanks Tom, good info. I do keep my hand reletively straight. I appreciate your input. Dan

Dan,

I really like the idea of this rod.

"I have the opportunity to build on a pretty unique S-glass blank for crankbaits and spinnerbaits. It's extremely light and the action is moderate yet strong. I will be building it with Fuji Concept Alconites
spiral wrapped."

What blank are you using? And maybe a little advice on how you are placing the guides? Sorry about the questions but I have only built fly rods so far.

Thanks,
Shawn Smith