New thread on DML's as a Full Range Speaker started here:
http://www.diyaudio.com/forums/full-range/272576-study-dmls-full-range-speaker.html
http://www.diyaudio.com/forums/full-range/272576-study-dmls-full-range-speaker.html
0.4x Karlsonator Score and Fold Method Plans
Finally! I have gotten far enough in my build to verify accuracy of my plans. I re-did the plans because I wanted to do the score and fold method and there were no plans for that. I made my model starting with the 0.4x Karlsonator scaling (detailed in the attached plans) and then I modeled the folded sections as sheet metal in SolidWorks. SolidWorks will "unfold" sheet metal parts, I just told it to apply zero stretching of the material on the outer radius of the bends. This way SolidWorks calculates the cut length and bend lines automatically. I have made the cuts and bends as shown in my plans and they work great.
I also included the aperture profile to scale so it can be used as a template. The aperture starts at a 3/16" width and the curve was calculated from the equation given by XRK (I can't find the post right now, but I think it's earlier in this thread).
As far as units go, I like to work with decimal inches but I know most people don't have decimal inch rulers (I have machinist rules I use). Most rulers/tape measures that are 30 inches long have 1/16 inch increments so I included dimensions on the cut diagrams to the nearest 1/32. That way people (in the USA at least) don't need special equipment or lots of work calculating to use these plans, you just need to be able to estimate half way between 1/16 inch marks. If there is a desire for a metric plan I can easily change the units (easy as making a selection from a drop down menu), so let me know.
I did not include my suggested brace from the modal analysis. I don't have a measurement microphone (yet) and I didn't want to show plans including something that's untested.
I tried to give all applicable credit on the first page. If there needs to be any corrections please let me know.
I hope others find these useful!
Finally! I have gotten far enough in my build to verify accuracy of my plans. I re-did the plans because I wanted to do the score and fold method and there were no plans for that. I made my model starting with the 0.4x Karlsonator scaling (detailed in the attached plans) and then I modeled the folded sections as sheet metal in SolidWorks. SolidWorks will "unfold" sheet metal parts, I just told it to apply zero stretching of the material on the outer radius of the bends. This way SolidWorks calculates the cut length and bend lines automatically. I have made the cuts and bends as shown in my plans and they work great.
I also included the aperture profile to scale so it can be used as a template. The aperture starts at a 3/16" width and the curve was calculated from the equation given by XRK (I can't find the post right now, but I think it's earlier in this thread).
As far as units go, I like to work with decimal inches but I know most people don't have decimal inch rulers (I have machinist rules I use). Most rulers/tape measures that are 30 inches long have 1/16 inch increments so I included dimensions on the cut diagrams to the nearest 1/32. That way people (in the USA at least) don't need special equipment or lots of work calculating to use these plans, you just need to be able to estimate half way between 1/16 inch marks. If there is a desire for a metric plan I can easily change the units (easy as making a selection from a drop down menu), so let me know.
I did not include my suggested brace from the modal analysis. I don't have a measurement microphone (yet) and I didn't want to show plans including something that's untested.
I tried to give all applicable credit on the first page. If there needs to be any corrections please let me know.
I hope others find these useful!
Mudjester: Thank you for an excellent set of plans for the 0.40x K'nator! 
I just updated Post#1 with the link so people can find it easily. I have used the sheet metal unfold method in SW too - works great. I used it to make the 2d cut plan for the curved wall tractrix horn.
For those in Europe or elsewhere without access to $1 dollar store foam core - corrugated white cardboard works very well too as long as it is about 3/16in (circa 5mm) thick. Why white color? The brown stuff is too ugly to make a speaker with
I just updated Post#1 with the link so people can find it easily. I have used the sheet metal unfold method in SW too - works great. I used it to make the 2d cut plan for the curved wall tractrix horn.
For those in Europe or elsewhere without access to $1 dollar store foam core - corrugated white cardboard works very well too as long as it is about 3/16in (circa 5mm) thick. Why white color? The brown stuff is too ugly to make a speaker with
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Mudjester: Thank you for an excellent set of plans for the 0.40x K'nator!
I just updated Post#1 with the link so people can find it easily. I have used the sheet metal unfold method in SW too - works great. I used it to make the 2d cut plan for the curved wall tractrix horn.
For those in Europe or elsewhere without access to $1 dollar store foam core - corrugated white cardboard works very well too as long as it is about 3/16in (circa 5mm) thick. Why white color? The brown stuff is too ugly to make a speaker with
Thank you! I'm very happy you like it!
I find it very odd how much I like making proper documentation.
It didn't occur to me about the difference in thickness of available materials. I can easily update the drawing with a new thickness. I constrained the model in such a way that it would be easy to update, but getting the bend radius right might be difficult. If someone can give me the outer radius of a bend with a desired material I'll create a new set of drawings for it.
That's really cool Muddjester.
I'd imagine coroplast would be another good material to try, as it is essentially plastic corrugated cardboard, and it comes in lots of colors.
Brown cardboard is cool xrk
Thanks Greg!
I think I know the material you're talking about, but isn't it usually kinda flimsy?Maybe that's just after the first bend. I don't know where to find it, but if someone wants a drawing for it, just let me know thickness and outer radius after a score and bend.
You're welcome!
Please let me know if you find any faults or would like some improvements. I'm hoping to document all my work to this level and it'd be great to know what works, what doesn't, and improvements that can be made.
Just ordered a pair of TC9FDs from PE. This will be a fun project. Love amazing non-audiophool friends with projects such as this.
When my old (redundant) friend from college first heard the transformation undergone by a 40-1197 going from free air to an enclosure, he exclaimed, "It's like turning water into wine." Can't wait to get his reaction when FC is involved.
Thank you xrk971 for the thread and Muddjester for the plans.
When my old (redundant) friend from college first heard the transformation undergone by a 40-1197 going from free air to an enclosure, he exclaimed, "It's like turning water into wine." Can't wait to get his reaction when FC is involved.
Thank you xrk971 for the thread and Muddjester for the plans.
Regarding Mudjester's excellent plans, for which I'm very grateful, in the process of making patterns from posterboard prior to transferring to FC, I have 2 questions.
First, there seems to be no part "I." Perhaps skipping from "H" to "J" is a convention of which I'm unaware. It would make sense. Is there a part "I"? If so, what is it?
Second, part "J," which is horizontal support for the K-slot board, seems to block the upper portion of the slot. Intuitively that seems problematic. Am I reading the plan incorrectly?
First, there seems to be no part "I." Perhaps skipping from "H" to "J" is a convention of which I'm unaware. It would make sense. Is there a part "I"? If so, what is it?
Second, part "J," which is horizontal support for the K-slot board, seems to block the upper portion of the slot. Intuitively that seems problematic. Am I reading the plan incorrectly?
with regular K made of plywood or particleboard, its helpful to use either wood dowel rod or steel allthread. Acoustic and other's little K employed 3/8" allthread. I've seen unbraced wings on Ultra Fidelity and klam deflect > 1/4" peak to peak on drum pulses including very fast tabla passages. K15 has a handy "shelf" which works well with wood dowel rods.
An externally hosted image should be here but it was not working when we last tested it.
Way cool! Karlson tech is the number 1 way to go - (I learned that some years ago but am not in good enough shape to build)
its more elegant and petite than my scrap K5
XRK971 Karlsonator 4
freddy rough K5
An externally hosted image should be here but it was not working when we last tested it.
Looks great, I will build this in 12mm hardwood for office speakers.