3D printed waveguides

[augerpro]

Ok, here are the 8" waveguides for the T34B. Also included a new 6.5" elliptical mouth with a higher aspect ration (1:.83). Also included a new 6" elliptical waveguide for the T25B (used my new family of speakers). I've decided to revisit the circular mouth on the SB26 family. The first is a 6.5" model, and it looks good, I'll move on to the other sizes when I have time. I've updated my website to include the new designs.















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[Dirk]

5.10.

The setting is under Experimental->Fuzzy Skin

As to layer lines, I'm on my second printer, and thinking about my third. I have seen enough prints with shallow gradients to know that there'd be plenty of stair stepping. The filament's natural glossiness just exaggerates it for me and bothers my inner fussbutt. Does anybody make a truly matte charcoal grey filament? That isn't filled with actual carbon fiber? LOL

I'll be doing at least one more. I'll skip the fuzz on the next one and report back. Whichever one I like...I'll reprint a 3rd. They really don't take a lot of filament. If I choose the "unfuzzed" texture, it'll be because I'm just gonna resin coat them. I'm also thinking about not completely tearing out the supports on the next ones, to resin fill from the back.

[aarond]

Brandon, you're a good egg. Thank you for expanding the state of our hobby.

Cura has some neat new features. One is a slight random jitter added to the outer perimeter. The magnitude of which is tunable, and I think it could be slightly reduced in this case. The OTHER feature that's super cool is variable layer height. The bottom of this model was printed at .3mm, and the top finished at .1, allowing the whole print to complete in about 16hr at a 72mm/s print speed. I'm going to a.) be enabling this setting quite often and b.) installing a larger nozzle to really make the most of it.

Is it better than skim coating & sanding? Nnnno, but the two features added together go a long way to reducing that "obviously 3D printed" look that all 3D printed parts have. They pass the "arms length" test nicely.

Now I just need to find time to get some test baffles cut!

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Have you done a complete print at .1 and .3 layer heights to compare the difference on the top layers? With PLA and a .4 nozzle I did a similar part both .2 and the default "dynamic quality" of .16. Other than the longer run time I didn't notice much if any difference where it should've counted the most.

Regarding "jitter" I did a quick google search to see what you are might be talking about. Is this the z seam alignment randomization or something else?

Which version of Cura are you using?

Aaron

[Dirk]

Brandon, you're a good egg. Thank you for expanding the state of our hobby.

Cura has some neat new features. One is a slight random jitter added to the outer perimeter. The magnitude of which is tunable, and I think it could be slightly reduced in this case. The OTHER feature that's super cool is variable layer height. The bottom of this model was printed at .3mm, and the top finished at .1, allowing the whole print to complete in about 16hr at a 72mm/s print speed. I'm going to a.) be enabling this setting quite often and b.) installing a larger nozzle to really make the most of it.

Is it better than skim coating & sanding? Nnnno, but the two features added together go a long way to reducing that "obviously 3D printed" look that all 3D printed parts have. They pass the "arms length" test nicely.

Now I just need to find time to get some test baffles cut!

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[augerpro]

I just updated the files and added a routing template you might find handy.

[Dirk]

Thanks, my dude!

I have a pair of RST28F sitting on the shelf, and been trying to find a WG to fit them. Thought I'd see how good of a print I could produce. ;-)

While I'm thinking of it, here's the recess guide I made recently for the SB H225. Similarly printed in 4 pieces, with interlocking tabs and small ears for more options to affix clamps that won't be in the path of the router.

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[augerpro]

The RST28 waveguides were the only ones I didn't update to prevent this, didn't think anyone was using them. I'll try to update the files today. I'll post here when I do.

[Dirk]

Hi Brandon!

Your RST28 vB noPS model is one of those with a gap that extends through the entire top plate (in the below image, it's the green arc). Cura is usually pretty good at detecting and closing these sorts of issues, but no luck this time.

Any guess whether that'd be an easy fix? Meshmixer terrifies me. Or barring that, I think Cura can open a .3MF. Perhaps it'd have better luck.

[augerpro]

Bliesma T34B fans, rejoice! Here are the results of two 6.5" waveguides. One has a circular mouth and the other elliptical. Now that I have a basis for further designs, I'll be doing a 8" and maybe 7.25". You can download the files here: https://www.somasonus.net/bliesma-t34b

[augerpro]

FYI, I ended up going with .stl over 3mf. When I tested a couple vendors, some don't recognize 3mf yet. This is a bummer because 3mf allowed including the engineering units in the file, so there would be no more confusion over metric vs standard. Also, weird internal faces throwing errors were supposed to be reduced because 3mf has a better storage format. Oh well.




On an upnote, wow have prices come down for printing! i.materialise.com quoted me $25 for nylon SLS (my favorite) on one of my 5" waveguides! Now I just have to understand their finishing options, I'm not sure you can "polish" SLS, at least without removing a lot of material.

[augerpro]

I've finally added router templates for elliptical waveguides to my website! You'll need 5/16" OD and 1" OD template guide bushings to use them. There are holes that will accept #4 sheetmetal screws, or you can use a finish nailer, or double-sided tape to attach them. https://www.somasonus.net/waveguides

[jhollander]

I like the blue tape on both pieces with CA glue in between. Small marks at the bottom of the template hole makes it easier to align the template. The router bushing rides higher than the marks or rides over any indentations.

[PWR RYD]

I'd rotate the SB woofer 90 degrees counter-clockwise

[a4eaudio]

Do a search for blue tape and super glue method or blue tape and CA glue method.
Also, maybe try a different double sided tape. The most recent stuff i got from Menards was way too sticky and would actually pull up the mdf. I settled on a compromise and used the blue tape with the overly sticky double sided tape in between.

[augerpro]

'm making a test cabinet to do some research on edges before I start final designs on a family of speakers. This gave me a chance tonight to try my routing template. Worked as expected, so I'll get them posted on the website soon. This will require changing all of the waveguides a bit, so if you are relying on using the routing template, I would hold off on downloading any waveguide files right now. You'll know when you can download them when the template files are available, and I always have a revision log at the top of every page where I note updates.



I tried using double-sided tape to hold the template in place, but it didn't stick well. I ended up using a finish nailer to attach. I thought about integrating screw holes into the design, but I like that the finish nail leaves a tiny mark that is easy to fill. Any other ideas for attaching them before I do a final template design?