60x40 HF-Horn

a couple thoughts after a second look…
is there a reason why your "ribs" are so short? making them longer like xt1464 could improve rigidity but maybe also help keeping the halves straight in the printing process.

another question, the termination seems a bit sudden compare to the flare, did you try and sim a shallower terminus, or a rounded one like again xt1464?

I know one has to design between constrains so maybe i was not possible.

Any way good pattern control for pa usable frequencies!

bob4 wrote: That print looks very good! On diyaudio.com someone else was 3d printing horns and had a lot more problems with cracks and warping...... If you oversize the print to have a bit of extra waste material at the edge, you could sand the edges of the two halves flat on a stone or glass slab with sandpaper glued onto it, to get a perfect fit without gaps. But i suppose fiberglass will be much stronger in the end.

Thanks for your input :) Since i have not enough filament left, my partner in crime prints another horn as one piece...but its just for the fun of it. I already made a plaster mold from my print (which was its whole purpose from the beginning)
I will keep you updated when i have more to show :)

odc04r wrote: I think is the DIYaudio thread you might be thinking of, a very large 2 part print for a unity horn mid-high segment, there's discussion of how some issues due to print bed induced warping etc were fixed due to the size of the prints https://www.diyaudio.com/forums/multi-way/312414-3d-printed-3-unity-waveguide-home-audio-speaker.html I've always wanted to do something similar, and I have access to an ultimaker with a decent bed size. But there is always something else first, it's quite far down the project list. Nice work though, always enjoy seeing designs come through simulation then a CAD/CAM workflow to reality.

Thank you :) i would say just go for it and print something....i mean what could go wrong? If you would like to print my design for testing or just for fun, i can give you the STL-File ;)

ARR_PG wrote: Did you use "subdomain modelling" in ABEC?

Yes i used subdomains in ABEC if that is what you where asking. Maybe you can elaborate your question a bit more so i can give you a better answer :) 

ARR_PG wrote: Cool. Ok. Just when you said you simmed without the IB Plane. I thought maybe you did not have subdomains.  I have this in most solving scripts.  Subdomain_Properties "Exterior"   Subdomain=4    ElType=Exterior    IBPlane=Pos;

Mine looks like this (depending of the simulation i want to do i just turn on or off the IB and Exterior)

JulianDA wrote: And now without the IB just because i did my measurements without any baffle (and yes, i know they look horrendous :D ): Directivity horizontal in 6dB steps Directivity vertical in 6dB steps

I have an quite exciting new update for you guys ;)
In the last few days i had enough time to finish my first try at molding the horn out of fibreglass and it worked better than i thought.

But first, this is the plaster mold i used:



I started with a layer of epoxy without the fibreglass (since i forgot to buy the gelcoat )



Then i added i piece of wood with the "flange mold" routered into (or out of?) it. Aswell as the first layers of fibreglass.



After that i did 4-5 additional layers of fibreglass and released the "flange mold" for easier acces to the rest of the horn. The result looked promising.



After a little bit more work i had the quite horrendous task to seperate the horn from the mold. But apparently the two liked each other so much, that they would not come apart without quite a fight (or i screwed up the measurement of the hardener in the first layer so it stayed tacky...we will never know ) The result was a damaged mold, but a somewhat presentable horn.



After a bit of cleaning it looked like this.




And this is the final result after a bit of sanding, some drilling, and a few layers of sprayed clear coat...and i have to say, i'm quite pleased with it for a first try and my second time ever working with fibreglass 





The next task is to take some more measurements and see if it works like i want it to. But since i am probably the slowest person on this site when it comes to working on projects, this may take a while.....again