Calculating Stages/Segment sizing.

[John Legg]

With my cognitive decline issues, I can’t think this through so that it makes sense. Help is welcome. I’m having difficulty describing the issue so bear with me. This should be applicable to Staves or Segments.

While designing a vessel using staves, how does one calculate or account for the veneer thickness added between the staves, when determining the width to cut the staves? It’s a brain fog as I try to think this through.

I get the concept if I were use solid pieces. But, when I through the process of including the veneers, I can’t see it in my mind what to do.

Thanks ahead of time.
John

 

[Brian Gustin]

With my cognitive decline issues, I can’t think this through so that it makes sense. Help is welcome. I’m having difficulty describing the issue so bear with me. This should be applicable to Staves or Segments.

While designing a vessel using staves, how does one calculate or account for the veneer thickness added between the staves, when determining the width to cut the staves? It’s a brain fog as I try to think this through.

I get the concept if I were use solid pieces. But, when I through the process of including the veneers, I can’t see it in my mind what to do.

Thanks ahead of time.
John

subtraction - whatever it takes to add all angles up to 360 degrees - Example - Solid wood 10 staves: 360 degrees divided by 10 = 36, However to get each SIDE of the stave, you want half that angle, so, you'd make 18 degree angle cuts (2 x 18 x 10 = 360) Now assuming you wanted to add veneers in between each stave (one either side), you'd have essentially 10 more staves , so you'd actually be doing 20 staves , thus 360 divided by 20 = 18 , half that is 9 degree cuts each side of the stave... (20 x 2 x 9 = 360) You'd just use PI to get the total circumference (diameter /2 = radius , then radius x 3.14 = circumference) if you want 10 pieces of veneer at 1/8 inch thick, subtract 10/8 inch (or 1-1/4 inch) from the circumference, then divide the remainder by the remaining 10 staves to get the stave width?

 

[Glen Crandall]

While designing a vessel using staves, how does one calculate or account for the veneer thickness added between the staves, when determining the width to cut the staves? It’s a brain fog as I try to think this through.

Adding veneer between the staves would increase the diameter of the project. To keep the diameter of the project as calculated, simply reduce the width of each stave by the thickness of one piece of veneer. The stave angles will not change.

 

[hockenbery]

get the concept if I were use solid pieces. But, when I through the process of including the veneers, I can’t see it in my mind what to do.

Think of the veneers as a thick glue line. The glue lines have thickness not much but they have it.
If you put veneers between each stave it doesn’t change the angles of the staves.
It will make the diameter a bit larger. Not by much for thin veneer.

As @Glen Crandall said for thicker pieces of veneer you need to change the segment size to keep the diameter.

 

[John Legg]

subtraction - whatever it takes to add all angles up to 360 degrees - Example - Solid wood 10 staves: 360 degrees divided by 10 = 36, However to get each SIDE of the stave, you want half that angle, so, you'd make 18 degree angle cuts (2 x 18 x 10 = 360) Now assuming you wanted to add veneers in between each stave (one either side), you'd have essentially 10 more staves , so you'd actually be doing 20 staves , thus 360 divided by 20 = 18 , half that is 9 degree cuts each side of the stave... (20 x 2 x 9 = 360) You'd just use PI to get the total circumference (diameter /2 = radius , then radius x 3.14 = circumference) if you want 10 pieces of veneer at 1/8 inch thick, subtract 10/8 inch (or 1-1/4 inch) from the circumference, then divide the remainder by the remaining 10 staves to get the stave width?

This makes sense. I appreciate it.

 

[Glen Crandall]

subtraction - whatever it takes to add all angles up to 360 degrees - Example - Solid wood 10 staves: 360 degrees divided by 10 = 36, However to get each SIDE of the stave, you want half that angle, so, you'd make 18 degree angle cuts (2 x 18 x 10 = 360). That is the well accepted math. Now assuming you wanted to add veneers in between each stave (one either side), you'd have essentially 10 more staves , so you'd actually be doing 20 staves , thus 360 divided by 20 = 18 , half that is 9 degree cuts each side of the stave... (20 x 2 x 9 = 360). I believe this is totally incorrect. Veneers will not be thick enough to support cutting angles. So adding veneers will only change the diameter of the project, not the stave angles. You'd just use PI to get the total circumference (diameter /2 = radius , then radius x 3.14 = circumference) if you want 10 pieces of veneer at 1/8 inch thick, subtract 10/8 inch (or 1-1/4 inch) from the circumference, then divide the remainder by the remaining 10 staves to get the stave width? I do agree with this last statement.

See my comments inserted above.

 

[Brian Gustin]

Veneers will not be thick enough to support cutting angles. So adding veneers will only change the diameter of the project, not the stave angles.

Good point... I hadn't considered "too thin" - however Veneers can be relatively thick depending on their sources, and I have seen segment wedges cut as thin as 1/8 inch (or less) Since I have yet to start experimenting with more complex segmenting, I would have to confess ignorance as to thin veneers changing the fitment of wedges or staves, or not... (However, I Can indeed see how it would work, once I had to think about it!)

 

[Paul May]

Adding rectangular strips between compound angled cut staves does not alter the geometry of the vessel; just the diameter. Stave calculators exist that can save you some math headaches. I recommend Wood Turner Pro as a great tool for this. It will provide you with all of the calculations you need to make the entire vessel.

 

[Don Wattenhofer]

Some examples of staved construction with accent pieces, which can be anywhere from 20 thousands inch to half inch or more. Notice all of the angle is made on the primary wood in this case walnut. The accent pieces have parallel faces so like others have already said only affects the diameter and any adjustments to the angle is done to the primary wood.

 

[John Legg]

Adding rectangular strips between compound angled cut staves does not alter the geometry of the vessel; just the diameter. Stave calculators exist that can save you some math headaches. I recommend Wood Turner Pro as a great tool for this. It will provide you with all of the calculations you need to make the entire vessel.
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Thank you Paul. I would like to use Wood Turner Pro but I do not have a Windows based machine (required). Only iMac and an iPad. It looks very complicated to run the program in a Mac OS environment. I will look into it further however. Your samples are exactly what I'm trying to accomplish.