Anybody have any experience modelling waveguides and getting them CNC milled into wood? I'm thinking multiple sheets of plywood stuck together for the depth.
I've seen the oblate spheroidal equation, how would one go about putting this through a CAD program? I've got sketchup....
How about a non-axisymmetric profile? Like the 18sound XT1086 but bigger to match bigger woofer...
Ta
I've seen the oblate spheroidal equation, how would one go about putting this through a CAD program? I've got sketchup....
How about a non-axisymmetric profile? Like the 18sound XT1086 but bigger to match bigger woofer...
Ta
Yes, I'm doing exactly that. I'm actually waiting to put my motorcycle engine back together before starting to cut a 320hz LeCleac'h horn. Sawdust in the crankcase = no good.
The details of drawing a curve like that in a Cad system vary with the system, but typically you'd draw enough points to describe the curve and then fit a spline through them. In my very limited experience with it, Sketchup is not what you want - it is for sketching, not for accurate technical models. That said, if it can export IGES or STL files, you might be able to make something useable with it but I would definitely check that first. Personally I use Pro/E or Autocad. Other packages to look at would be Solidworks, Unigraphics, Catia, etc. Solidworks is probably your best bet. The others are expensive. I haven't used the latest version of AutoCAD, but in the older ones (just a few years), you can't draw something like an elliptical horn as a solid model.
Another thing to watch out for is what CAM software your CNC shop has. If they don't have something moderately complex, they won't be able to cut out 3D shapes like this - well, they won't be able to import a 3D model and from that program the cutting paths for the shapes. A lot of shops with operators who are more experienced with the machining side and less with the computer and cad side don't have the necessary software in my experience, as this software is also not cheap.
The details of drawing a curve like that in a Cad system vary with the system, but typically you'd draw enough points to describe the curve and then fit a spline through them. In my very limited experience with it, Sketchup is not what you want - it is for sketching, not for accurate technical models. That said, if it can export IGES or STL files, you might be able to make something useable with it but I would definitely check that first. Personally I use Pro/E or Autocad. Other packages to look at would be Solidworks, Unigraphics, Catia, etc. Solidworks is probably your best bet. The others are expensive. I haven't used the latest version of AutoCAD, but in the older ones (just a few years), you can't draw something like an elliptical horn as a solid model.
Another thing to watch out for is what CAM software your CNC shop has. If they don't have something moderately complex, they won't be able to cut out 3D shapes like this - well, they won't be able to import a 3D model and from that program the cutting paths for the shapes. A lot of shops with operators who are more experienced with the machining side and less with the computer and cad side don't have the necessary software in my experience, as this software is also not cheap.
Cool, I'll check out solidworks...
Is this true of all woods? How bad is it? What about when painted/sealed? (I obviously have no experience here) I notice people building Gedde's kits painting the waveguides, but I'm not sure if that's all the way into the throat.
Are there any other materials suitable for this sort of thing? I'm only building 2... These aren't for prototypes, and they'll get used outdoors sometimes.
Does anyone have equations for an elliptical waveguide?
Thanks,
Is this true of all woods? How bad is it? What about when painted/sealed? (I obviously have no experience here
) I notice people building Gedde's kits painting the waveguides, but I'm not sure if that's all the way into the throat.Are there any other materials suitable for this sort of thing? I'm only building 2... These aren't for prototypes, and they'll get used outdoors sometimes.
Does anyone have equations for an elliptical waveguide?
Thanks,
The oblate spheriodal waveguide contour is public domain and is desribed in the thread mentioned above. But the elliptical version has never been defined - publicly. Here is a picture of the one that I had cut. Way too expensive to do as an actual device. The costs only make sense if you can mass produce them.
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Re: Waveguide milling
Uh, CNC doesn't come cheap!! Its several thousand to do what you see.
Sure its easy if you have the machine, the machine does the work! Are you saying thta you will do CNC work for me for free? I WOULD take you up on that!!
Any form of glass is time consuming and costly and ends up with only an average product. I wil never use glass again.
fb said:
Uh, CNC doesn't come cheap!! Its several thousand to do what you see.
optichammer said:
Sure its easy if you have the machine, the machine does the work! Are you saying thta you will do CNC work for me for free? I WOULD take you up on that!!
Any form of glass is time consuming and costly and ends up with only an average product. I wil never use glass again.
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