Two axis bent leg, how to make it?

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Hi everybody.
This thing is driving me nuts, I have designed a table that has curved legs on two axis.
I have designed it in my CAD software in 3D and generated the ortographic views of on leg to figure out how I should build it.
First thing that I see is that in order not to waste wood I should make them laminated. What I have not clear is how I should proceed.
I figure out that I should make a mold with the curvature of the side view and laminate stripes of the maximum width of the front view until I had achieved the thickness of the side view.
Once dry draw the profile of the front view on the piece and cut it on the band saw.
Here come the doubts:
As far as I understand the front view as it is an ortographic projection will not be valid to be drawn onto the curved piece and it should be drawn in it true magnitude, I mean as a developed surface (see schematics).
Not only that, but also I think that the mold should have an inclined rebate to position the strips as if they were cut of the maximum size of the ortographic projection, but with the length of the true magnitude profile isn’t it.
I don’t know if I conveyed my ideas and problem properly. Any suggestions or comments will be appreciated.
esquemas.jpg
 
My solution to not trusting a drawing to tell me what I think I want to know is to make a cardboard mock up. Take your front profile and make a corrugated cardboard pattern of fit. Make enough pieces to glue them together (lamination) and then mark out your side view on them. (paste paper over the corrugated eges so you have a surface to draw on.) See how it looks. Make adjustments, then cut on the band saw. Now you have a cardboard model and you have learn a lot of hands on information. And you have a pattern to transfer to the wood later.
 
Hi Carol.
I'm not sure to follow you correctly. Do you mean to make a block of corrugated board of the dimensions marked of 480 x 175 x 553 mm (see sketch) draw the front and side views on it and cut them on the band saw?
That would give me a mockup of the leg of course but I cannot follow that procedure in wood, hence my question about laminating it.
esquemas 2.jpg

Or what you mean is obtaining the profile in true magnitude by that procedure?
 
Toni, I hope this will assist you with your project. I did this to make the legs on this table.
P3300007.JPG

I started by gluing up four boards ... and matched up the grain as best I could:
PA250011.JPG

I then jointed, planed and cut them to length:
PA250013.JPG

Then I put a pattern on each side and traced the outline:
PA250015.JPG

Then I cut on the band saw:
PA250016.JPG PA250019.JPG

Hope this helps you. Looking forward to seeing your finished table.

Then I taped the cutoffs back onto the leg, rotated the leg 90 degrees and then cut on the band saw again:
PA250020.JPG

I ended up with this:
PA250022.JPG PA250023.JPG
 
Toni, what Robert did, only in cardboard first.

I think trying to laminate in both planes, especially at the same time, is way more difficult and maybe not really doable. If you laminated in one plane and try to cut in the other, you need to consider how to support your piece through the saw. Robert covered that by taping on the cutoff from teh first cut to make the second. Hope that helps.
 
Toni, what Robert did, only in cardboard first.

I think trying to laminate in both planes, especially at the same time, is way more difficult and maybe not really doable. If you laminated in one plane and try to cut in the other, you need to consider how to support your piece through the saw. Robert covered that by taping on the cutoff from teh first cut to make the second. Hope that helps.
 
¿You are asking "where is the 'plane' that I have to bend the lamination along in order to match both curves simultaneously"?

Well... not exactly what I am asking is wether my approach is the right one or not, and if not how should I make it.
The idea is to bend/laminate on curve and get the other one on the band saw, doing what Carol and Robert suggest.

Carol, I'm not trying to laminate on both planes, just one to save wood. If you look at the position and length of the side view vs the front view the amount of wood to use is outrageous as well as the amount of waste, if I made it out of a block of wood because its measures should be the ones I mentioned.
 
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The issue wll be to support the curved first plane for the bandsaw cut of the second plane. Maybe you can hot glue supports on for teh ride through the bandsaw.
 
If you look at the 3D drawings you'll see that cutting the leg from a block of wood is out of question, so I thought about laminating following the side view profile and cut the front view profile from it. But as you can see the front view profile cannot be drawn direcly onto the curved surface or side of the laminated part because it is not drawn in its true magnitude ( I don't know if you use this expresion) because it is an ortographic projection; so its length does not match the length of the curved surface.

Imagine that I cut a carboard template out of that front view, how could I transfer the profile onto the curved surface of the laminated part? I cannot, hence my question about everything.

esquema 1.jpg
 
Well... not exactly what I am asking is wether my approach is the right one or not, and if not how should I make it.
The idea is to bend/laminate on curve and get the other one on the band saw, doing what Carol and Robert suggest.

Carol, I'm not trying to laminate on both planes, just one to save wood. If you look at the position and length of the side view vs the front view the amount of wood to use is outrageous as well as the amount of waste, if I made it out of a block of wood because its measures should be the ones I mentioned.

If you were to cut the part as drawn: 1) you would waste a lot of wood; 2) the grain would run across the part so would be weak.

If you were to rotate the part to be as close to following the grain as possible, in both planes (my hint above), there would be less waste and the measurement problem should disappear.
 
I think I've found why it is so difficult to make this leg. The section of the leg it is not square as I presumed but it is trapezoidal. As the top of the table is going to be glass, I found that it woud be good that the top of the leg would be square as seen on top view. As I drew the 3d leg from side and front views the leg section is not square, but trapezoidal, but it becomes square when cut by a plane parallel to the ground.
So it would ve very difficult to cut this leg on the band saw as the angles of the trapezoid change along the curvature of the leg because thickness changes. So I think that in order to obtain the square section on top, I will have to cut the side view (bottom left) and then draw on each sides of it the two sections ( front & back) and shave them with a spokeshave or with a rasp.

I have included three legs the original, the same with the cutting plane and the resultant one with the trapezoidal section showing. If you look at the bottom right view all of them look the same in ortographic projection. So if I wan to make the leg on the band saw, either I make them almost by hand or I put up with having a trapezoidal section shown under the glass if I make the leg of square section to cut it easily on the band saw.

I include a drawing to show how the table will look but this is not by far the design, it is just to show you how the legs will be respect the top of the table. The design will remain secret until I make it having solved all problems.

Geez this project is making me think a lot.!!!!!
esquema 2.jpg esquema 3.jpg
 
In a word, Prototype.

Buy some cheap solid wood, pine, whatever, try making one, fail, learn something, try again.

Thats how guys did it for a very long time before we got computers to spend time on :D
 
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