How do you find the spine on a 4, 5 or 6 piece.

The method I use is to bend slightly the section and find its point of resistance by rolling in the palm of my hand.

Since a multiple piece has shorter sections which are stiffer and harder to flex like this how can I find the spine?

Do all factory blanks come marked with the spine as Sage does?

Sage blanks are not marked for spine. They are marked for straightest axis.

The spine is not the plane that offers the greatest resistance to bending. It is the outside of the bend you find when you have it in a position where it offers the least resistance to bending.

The FAQs page explains what you can do when working with short sections that are difficult to flex.

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according to the data I've read guides should be marked on the spine or 180 degrees opposite. I find this and actually put my guides on the spine.

I used Art schecks method.

There are a lot of various ways to do this - none are necessarily right or wrong, however...

You have to decide what you want the effective spine to do for you. Do you want it working for you in the plane of the cast? If so, putting the guides on the spine may put the spine at 90 degrees to the casting plane, particularly if we're talking about a bait casting rod.

The spine cannot be used to make a rod stable - only guide placement can do that.

The stiffest axis is generally neither on nor opposite the spine.

These are just some thoughts you can consider when determining where you want your spine located.

The FAQs page contains the 3 most popular placements for the spine and what you can expect from each.

Art is a fine editor (much better than I am) but as he's told me more than once, he's not a serious rod builder. His information on locating the spine is 100% incorrect. What he is locating is the stiffest axis, which is not the spine nor opposite the spine. Of course, you can use the stiffest axis if you wish. Again, consult the FAQs page for more info.

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