Back Plate Center Stripe

[hawthorn1213]

Quick question for my current build regarding the center stripe on the back plate:

Is it better to sandwich a thin strip of wood between the two plates while gluing, or glue the two plates and route a channel for the center stripe?

It would seem that a routed channel would yield a stronger joint (and be easier to fabricate, at least for me.) What are your thoughts?

[Paul Busman]

I'm not a luthier but for my two cents, I'd imagine that a lot would depend on what wood the stripe was made of. If it was as strong or stronger than the back,and is a species that takes glue well, gluing it in first might be OK. It would look cool through the sound hole(s) too.
In making wooden penny whistles, I've discovered a LOT of species that I wouldn't trust. All in all it might be better to route a channel and glue in the strip.

[buckhorn]

I would be concerned with loss of strength if routed in an already shaped back plate. That carved plate is pretty thin when carved. My choice would be to put the strip in when glueing the two halfs together. I do this with 3pc necks and works out great for me.

[pops1]

Guitars have a center seam inlay most often and are usually routed in. They are thin wood, but it doesn't have to be deep.

[sunburst]

Traditionally, guitar back strips are glued between the back halves, not inlaid in a channel. Perhaps many current builders inlay the back strip, but in either case, the back joint is usually reinforced with a graft inside so the loss of strength from the center strip (whether inlaid or "sandwiched") is not too significant.
The OP didn't say that this is an carved back plate so I assume it is a flat back, but if it is an arched back, installing a graft is not practical, so perhaps a center strip needs some consideration. If it is flat, depending on what the center strip is; a solid piece of wood, a length of veneer, a marquetry strip, or other, that would probably determine how I would proceed.
I have seen center joints in upright bases that are reinforced with a series of diamond cleats for the full length.

[Timbofood]

I would be concerned with loss of strength if routed in an already shaped back plate. That carved plate is pretty thin when carved. My choice would be to put the strip in when glueing the two halfs together. I do this with 3pc necks and works out great for me.

Wouldn’t those be three and five piece necks (not counting the “ears” of course.)? I’d think the contrasting strips count as well but, I’m a bit of a nit picker.

[buckhorn]

I just posted a quick pic of how I handle a three piece neck with a center strip. And that would probably be how I would handle a strip through the back plate. Trying to route a groove through an arched, carved plate would be a real trial in craftsmanship.. Thickness in the center is at most .20 and less and less as you go to the recurve. I'm not wanting to retract anything from the original post...Just saying what I would choose.....

[hawthorn1213]

Thanks everyone, I appreciate the input! The will be for a flat top.