Spline Loft Sculpture

ZooHead said:
What are the standard plywood thicknesses in Germany?

I'm wondering if the thin vertical fin could be one piece of plywood.
If so some of the UVs are not needed.
Click to expand...
I will use a thickness of 3mm, that is pretty standard. One plate is around 2x3m if u buy them at a big wood shop, they can cut it down to the size the laser cutter can handle, but that size I have to check when everthing is ready. A common size would be 60x80cm.

If I make that fin of solid plywood it would be very heavy what I want to avoid under any circumstances (for structural reasons and reasons like transport or mounting) and it would bend over time, maybe.

If that thin fin is only 10mm, it should be made at least 16mm (2x3mm hdf + 10mm carbon rod). I thought you said earlier it has a thickness of somehing like 2,25cm. ;)
 
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Thin fin at 0.16 scaled x10 = 1.6 cm = 16mm.

Thin Fin Adjust 02.jpg
 
Great Eric,
let‘s just use 29mm, 23mm, and 16mm… it will be a compromise for structural reasons, but should be good. Thanks :)
 
btw. you can just use round everything to full mm. so, 0,2228=0,223=22mm… if that makes working and scaling easier to work with.
 
I made them 16, 23 and 29. For this I used Normal Move in the Polygon
menu and have a great deal of accuracy with it, 5 or 6 decimal places.

There's also the benefit of keeping the same thickness the entire length.
When the zigzaggy panels/fins where scaled in one direction, it introduced
variations in the thickness of the panel because of the varying angles.

Normal Move moves polygons perpendicular to there surfaces so all
the vertical fins should have equal thickness for their entire length.
 
I realized I was wrong to use Normal Move and Shell to try to keep
the fin thickness consistent for thickness for the entire length.

I was over thinking things.

The important measurement is at the joint between sections, where the splines where.
So to make the fin I made a copy of one side, and flipped the Normals.

To get the copied side to move horizontally the distance I want I used the
Transform Tool Panel to add or subtract the dimension in the proper field.

I will show this tomorrow when my eyes aren't so blurry. :sleep:
 
I'm going to try and show as many basic operations as
I can here so Gerald can learn as much as possible.

To make these GIFs as small as possible I have to limit the colors on the screen.
That means no interface, instead I'll indicate in text the Tool, Modifier Key
and the Mode Cheetah is set to either Polygon, Edge or Point.

To rebuild the "fins" I first have to delete everything but one side of each fin.

finremake01.gif
 
Now I simply copy and paste, Flip Normals and then I type -0.19 into the proper field in the Transform Tool panel.

Then I finish up by using the Bridge Tool.

finremake02.gif
 
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The traditional joining method for laser cutting is to make tabs and notches.
I wanted to see if I could use Cheetah 3D to make them and
avoid the nightmare step of making them in Illustrator.

For a form with everything square and perpendicular it's no problem
but introduce any angles and it's a whole different tedious method.

But it looks like it's possible. The gif shows the required 3mm panels.

Bonus Notches.jpg


bonusnotches.gif
 
Hi Eric,
yes, I want to use these method, if this is possible to do in Cheetah3D, that would great, of course. From my experience there should be more tabs/notches... like tabs/notches with 10-20cm. But this whole topic is not easy to do before talking to the laser cut service... I can remember that I had to add something like 0,2mm to the tabs to have a tight joint. If it's only a little to big it wont fit, if it is too small it is totally loose.

I think the tabs should be done after I have talked with a laser cut service, and therefore it would be best to have all the cutting pdfs... I think I have to talk to different services because I think the cutting price will be very different, years ago it was a to good thing to do a small test cut just for the tabs/notches.

Thanks a lot.
 
GS089 said:
Hi Eric,
yes, I want to use these method, if this is possible to do in Cheetah3D, that would great, of course. From my experience there should be more tabs/notches... like tabs/notches with 10-20cm. But this whole topic is not easy to do before talking to the laser cut service... I can remember that I had to add something like 0,2mm to the tabs to have a tight joint. If it's only a little to big it wont fit, if it is too small it is totally loose.

I think the tabs should be done after I have talked with a laser cut service, and therefore it would be best to have all the cutting pdfs... I think I have to talk to different services because I think the cutting price will be very different, years ago it was a to good thing to do a small test cut just for the tabs/notches.

Thanks a lot.
Click to expand...
I agree, more tabs are needed. I was just doing my first test and simpler is better.

It would make sense to me for the laser cutter to be able to
shift the laser to cut inside, outside or on the vector line.
 
Helmut said:
:unsure: I would assume that those tabs & notches will be a major problem when laser cutting the curved elements. However, I can´t quite recall the geometry of these sails (they are shown as splines only in posting #1 by ZooHead) and I can´t find the original thread, which, (I dimly recall) goes back to a model proposed - or even built - 100 years ago (possibly even in Wilhelminic II times or early Weimar Republic) to represent a musical composition.
* I remember looking that up (and even finding some reference) but I simply forget the query parameters.
Click to expand...
I'm trying to ignore the curved pieces for now. ;)
 
While we wait to see what the laser cutter services can do, I'll build a version designed for rendering.
I'm not going to make it look like the laser cut version with the tabs and notches.

The obvious thing I have to do is give the Bridge/Element 2 object some thickness.
The other change is to give any hard edges some degree of radius.
This catches the light and highlights an edge.
 
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