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7K views 64 replies 26 participants last post by  JoeLyddon 
#1 ·
First Steps

My son was searching for unusual speakers on the web and he found a nautilus seashell style that he liked similar to this one. Most were molded with some type of plastic. The one shown below was 3D printed except for one which was made of plywood.

Ammonoidea Organism Nautilus Chambered nautilus Symmetry


Art Wood Automotive design Sculpture Automotive wheel system


Here is the only plywood on the net as far as I know. there was no construction information available for this one, so I had to figure out how to make it myself. It was made by James Meacham at this website.

Furniture Wood Natural material Table Flooring


My son asked me if I could make him a pair of small similar speakers. Being somewhat innocent and naive I said sure, no problem. Now I just had to figure out a way to do it. Initially it didn't seem so challenging. Here are some of the things I would need.

A flat drawing with the segments drawn in like this

Wood Font Art Tints and shades Circle


3/4" baltic birch plywood wedges cut to the exact size and angle of each separate segment like these

Wood Hardwood Engineering Tool Table


My son did the outline shape and printed it out for me then I drew in the segments. There are at least 11 different radiuses involved, so the inside thickness of each segment was slightly different creating different angles, but I was able to keep several radiuses the same before changing as needed. This did however require just eyeing them in a bit off and on to compensate, otherwise the wedges would become distorted and throw the proportions out of whack and the shape would not consistently curl into the middle.

Each segment would have to be first cut into flat square shapes to the appropriate sizes. Then those squares would have to be cut into wedge shapes as in the drawing. After that, they could then be scroll sawed round and with a hole in the middle to make the eventual shell shape hollow.

In theory this seemed fairly straight forward, but the devil is in the details as they say. After 4 attempts I finally worked out the wrinkles. My next blog in this series will discuss the problems I encountered with the different elements of the work and how I eventually solved them.

I will admit that my reasoning powers are not as keen as some of you, so it will be interesting to hear of any better ways out there to do this work. I am not intending to make any more of these myself, but it might benefit others who wish to give it a go.

Thanks for reading and I hope you will enjoy this series.
 

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#38 ·
Cutting the Wedges to fit the pattern

Here is a teaser so you can get an idea of the size of the horns. Keep in mind that there will be trumpet like ends attached to the horns. I will be making these end pieces with plywood rings similar to segmented turnings and turn them on my lathe.

Wood Tire Automotive tire Tread Serpent


Once the individual segments were cut, they needed to be cut into wedges so that they would form the curl in the horns. The outside thickness (or top) of the segment squares would remain the same. The inside edge, (or bottom) of each square would vary from about 3mm or 3/32" to 5mm or slightly less than 1/4".

Perhaps the biggest challenge of the whole project was finding a way to cut these wedges dead accurate leaving a very flat surface on the cut side that would glue-up without any gaps. The dimensions were taken directly from the pattern for each segment as shown below.

Product Wood Brush Table Paint brush


After several failures I finally came up with a procedure that worked. This required the following:

  1. A clearly marked cut line. This was accomplished by gluing white paper to the top of each square before marking. 1st photo below
  2. A hefty woodblock to manually hold the workpieces firmly against the miter saw fence. Each workpiece was stuck to the woodblock with double sided tape. I was able to cut two wedges with one piece of tape before replacing with fresh tape 2nd and 3rd photo below

Wood Flooring Publication Rectangle Floor


Table Wood Rectangle Wood stain Hardwood


Automotive tire Wood Automotive design Motor vehicle Gas


After cutting all the wedges they looked like this photo below

Plant Table Wood Flooring Hardwood


I ran into a lot of problems cutting these wedges before coming up with procedure outlined above. I tried several methods of cutting them which failed. I first tried to do it with my bandsaw because I couldn't come up with a safe way to hold the on-edge workpieces in the miter saw. The cuts were not perfectly flat or particularly accurate and the changing angles required continual adjustment to the table angle, which is not the easiest to do with my bandsaw. Here is a picture of that failed set-up below

Wood Flooring Floor Hardwood Composite material


The other problem was making a clearly marked cut-line which was eventually solved with the papered edges.

My next blog in this series will cover additional necessary markings, cutting to round on the scroll saw and glue-up.

Thank you for following along. Please let me know if you have any questions or need to clear up any of my wordy explanations. You may have better ways to do some of the operations outlined above and if you do please share them.
 

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#39 ·
Cutting the Wedges to fit the pattern

Here is a teaser so you can get an idea of the size of the horns. Keep in mind that there will be trumpet like ends attached to the horns. I will be making these end pieces with plywood rings similar to segmented turnings and turn them on my lathe.

Wood Tire Automotive tire Tread Serpent


Once the individual segments were cut, they needed to be cut into wedges so that they would form the curl in the horns. The outside thickness (or top) of the segment squares would remain the same. The inside edge, (or bottom) of each square would vary from about 3mm or 3/32" to 5mm or slightly less than 1/4".

Perhaps the biggest challenge of the whole project was finding a way to cut these wedges dead accurate leaving a very flat surface on the cut side that would glue-up without any gaps. The dimensions were taken directly from the pattern for each segment as shown below.

Product Wood Brush Table Paint brush


After several failures I finally came up with a procedure that worked. This required the following:

  1. A clearly marked cut line. This was accomplished by gluing white paper to the top of each square before marking. 1st photo below
  2. A hefty woodblock to manually hold the workpieces firmly against the miter saw fence. Each workpiece was stuck to the woodblock with double sided tape. I was able to cut two wedges with one piece of tape before replacing with fresh tape 2nd and 3rd photo below

Wood Flooring Publication Rectangle Floor


Table Wood Rectangle Wood stain Hardwood


Automotive tire Wood Automotive design Motor vehicle Gas


After cutting all the wedges they looked like this photo below

Plant Table Wood Flooring Hardwood


I ran into a lot of problems cutting these wedges before coming up with procedure outlined above. I tried several methods of cutting them which failed. I first tried to do it with my bandsaw because I couldn't come up with a safe way to hold the on-edge workpieces in the miter saw. The cuts were not perfectly flat or particularly accurate and the changing angles required continual adjustment to the table angle, which is not the easiest to do with my bandsaw. Here is a picture of that failed set-up below

Wood Flooring Floor Hardwood Composite material


The other problem was making a clearly marked cut-line which was eventually solved with the papered edges.

My next blog in this series will cover additional necessary markings, cutting to round on the scroll saw and glue-up.

Thank you for following along. Please let me know if you have any questions or need to clear up any of my wordy explanations. You may have better ways to do some of the operations outlined above and if you do please share them.
This is quite an interesting blog to follow!
 

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#51 ·
Marking and more Cutting

This is one of the two 90% finished horns being made.

Wood Serpent Tire Automotive tire Wool


Last time the square segments were marked out and cut into wedges according to the pattern.

Now it's time to mark out for cutting in the scroll saw. This marking was for an earlier failed rendition and the inside diameters were enlarged for the final horns.

Wood Rectangle Material property Art Tints and shades


After cutting the the segment round and hollow now a centerline on the thick top edge and the same on the bottom thin edge was marked out. This is to aid the correct alignment of the segments during glue-up. I learned later (too late) that it would have been even better to mark the centers on all four edges, but it worked out fairly well anyway with only two marks. I didn't get any photos of this, but it is pretty self-explanatory anyway.

With most of the 112 pieces cut, the next task was to start gluing up. The 1st photo shows a horn loose assembled before glue-up and the 2nd photo shows how the glue-up proceeded first in small sections to keep it all manageable. Both of these photos were of an earlier failed version with thinner walls, but they illustrate how it was done.

Wood Ammonoidea Adhesive Nerve Automotive tire


Wood Flooring Hardwood Wool Plywood


After gluing up the sections I wound up with the horn shown in the 1st photo above. The 2nd horn is still in sections awaiting final assembly and gluing. I plan to do that and also complete the final pieces in the center of the curls. The final job will be the sanding and then I can move on to the trumpet style tips seen in the pattern. These will be like bowls without a bottom and turned on my lathe.

I will continue this blog to the end so you can see the entire project carried out. Not sure how soon that will be as my health has been keeping me out of the shop lately, but not before after the holidays for sure.

Once again, thanks for following with and I hope you and your families have a very Merry Christmas and a Happy New Year!
 

Attachments

#52 ·
Marking and more Cutting

This is one of the two 90% finished horns being made.

Wood Serpent Tire Automotive tire Wool


Last time the square segments were marked out and cut into wedges according to the pattern.

Now it's time to mark out for cutting in the scroll saw. This marking was for an earlier failed rendition and the inside diameters were enlarged for the final horns.

Wood Rectangle Material property Art Tints and shades


After cutting the the segment round and hollow now a centerline on the thick top edge and the same on the bottom thin edge was marked out. This is to aid the correct alignment of the segments during glue-up. I learned later (too late) that it would have been even better to mark the centers on all four edges, but it worked out fairly well anyway with only two marks. I didn't get any photos of this, but it is pretty self-explanatory anyway.

With most of the 112 pieces cut, the next task was to start gluing up. The 1st photo shows a horn loose assembled before glue-up and the 2nd photo shows how the glue-up proceeded first in small sections to keep it all manageable. Both of these photos were of an earlier failed version with thinner walls, but they illustrate how it was done.

Wood Ammonoidea Adhesive Nerve Automotive tire


Wood Flooring Hardwood Wool Plywood


After gluing up the sections I wound up with the horn shown in the 1st photo above. The 2nd horn is still in sections awaiting final assembly and gluing. I plan to do that and also complete the final pieces in the center of the curls. The final job will be the sanding and then I can move on to the trumpet style tips seen in the pattern. These will be like bowls without a bottom and turned on my lathe.

I will continue this blog to the end so you can see the entire project carried out. Not sure how soon that will be as my health has been keeping me out of the shop lately, but not before after the holidays for sure.

Once again, thanks for following with and I hope you and your families have a very Merry Christmas and a Happy New Year!
Best of the season to you Mike. You take care of yourself first, .... please.
Great project and blog.
 

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