Is there a structural need to cut ribs at lower block?

[Will Turner]

When I have the opportunity for cutting my rib material long enough, I prefer to not cut at the bottom block.   Instead I bend the entire lower bout in one go.

Is there a structural need to cut ribs at the lower block?   All the making materials has that, but I dislike my knife cuts so avoid it.

Anyone else do a complete lower bout in one bending?

Edited March 12, 2025 by Will Turner
Added image

[Don Noon]

No, there is no need to have the lower ribs into pieces, except for a visual symmetry. One piece would be structurally better, since it avoids a joint.

[jacobsaunders]

There is no “need” to make a bottom rib in two pieces, if you are using an inside mould, unless your piece of wood is to short. In fact, if the wood is long enough, you would have to be quite a head-banger to cut it in half and then join it again. The “need” comes if you are making the ribs “on the back” without a mould with pre-fabricated ribs, also with some forms of outside mould (for instance as described by Herron-Allen)

[Davide Sora]

Mr. Stradivari and the other Cremonese of the company did it, it is part of the traditional Cremonese method.

I do it too, when I have long enough pieces. Both the upper and lower ribs. For the upper rib it was used to reinforce the block where they planted the 4 nails to fix the neck, now it wouldn't be needed, but while I'm at it...

[Will Turner]

@Davide Sora, @Don Noon and @jacobsaunders thank you!

Appreciate your information!

[David Beard]

Uncut was the Cremona way.

[match]

Is the cut not made for the reason to have the connection to the same direction of the flames on the back if you have a two part back?

[Will Turner]

11 minutes ago, match said:

Is the cut not made for the reason to have the connection to the same direction of the flames on the back if you have a two part back?

If so, I didn't follow that on my last build.

Single Rib lower bout and single upper.  

Camera glare makes it look like varnish damage, lesson learned?  Turn off the flash.

My upper bout does have the flames more perpendicular, I don't notice a clash on the other side.

[match]

If the flaming of the ribs is perpendicular, it doesn’t matter, of course. If everything is perpendicular, it doesn’t matter either. Stradivari and Guarneri didn’t care at all - often, the direction of the flaming on all three bouts is different. I don’t really care either, but that’s how I learned it… And no there is no structural need

[Hempel]

Is the tear-out (and apparent kinks) on the lower rib at the bass corner in the OP anything to be worried about?

[Will Turner]

No kinks,  however it will have a scraper run over it once lined.   I used a smaller plane that wasn’t full width of the rib, so perhaps that is what you see.

[Andreas Preuss]

If you think of structural needs for long term use there are many things which are not optimised

[Will Turner]

2 hours ago, Will Turner said:

No kinks,  however it will have a scraper run over it once lined.   I used a smaller plane that wasn’t full width of the rib, so perhaps that is what you see.

Also there is a dark grain I am pointing to, could look like a tear out.

top view shows no kinks.   I do see that the figure of the maple looks like a kink face on at about the same pencil point.

does not show on inside.

[Hempel]

3 hours ago, Will Turner said:

Also there is a dark grain I am pointing to, could look like a tear out.

top view shows no kinks.   I do see that the figure of the maple looks like a kink face on at about the same pencil point.

does not show on inside.

 

At the left corner block there are definitely two distinct kinks very visible in the plan view.  Something (like a plane blade) has cut deep into the rib in two separate places.

I'm reminded of a scene from "Breaking Bad:" 

 

[Will Turner]

2 hours ago, Hempel said:

At the left corner block there are definitely two distinct kinks very visible in the plan view.  Something (like a plane blade) has cut deep into the rib in two separate places.

I'm reminded of a scene from "Breaking Bad:" 

Thanks, I had dismissed it as a concern and was focused on the bottom block.   Guess I am a blockhead to have missed what you had seen in first post.
I  remember looking at it before gluing it and realizing it is not full length, it’s like one started and about 3mm or less deep at that part.  Fortunately doesn’t extend further.  And I have not table sanded the garland down yet.  Was going to finish the top and reduce it down from ~34mm to 30mm top and 32mm C bouts and down.   I will post it when I get to that point.  Should be removed with the amount of material to remove.

Apparently I had pressed it at an angle to the iron to have it happen?  I definitely need more practice making sure I press straight onto the iron and go slow.

Well figured ribs needs just a little bit more skill than I thought I have.  My first violin, this is my third, was almost no flame.   Didn’t want to waste the good wood on my very first try.   

[Will Turner]

 

Ribs removed from inner mold.   Still need to chamfer and clean up the interior.   I also provided a closeup of the corner block where there was a concern about kinks to the rib.   Fortunately the issue was just the first 3mm which was trimmed off when I reduced the width at the block to 32mm.

 

bottom block view

top block view (had enough to keep it continuous as well)

left bottom corner originally of concern.

c bout to show corner trimmings.