I used Tractrix _V1.4b to design a 185 Hz horn using Inlow sounds .inlowsound.com method of making a mold and building the cones out of paper mache. I am not connected to them in any sense. I have never communicated with him either. Although it probably would have been a good idea. I did just finish and pulled the second horn off the mold. I do not have storage space for the mold and am willing to make someone a terrific deal. It has a 55mm throat and is 610mm in length and 594mm diameter mouth. It is painted with catalyzed urethane automotive paint. Sanded smooth with 2000 grit and polished. I am using Dynaudio D54af for drivers but a low frequency 2" compression driver would be better. I hate to take a hammer to my covid 19 lock down work, but it has to go soon. I have learned a few things and can pass that along as well. I am located on the Southwest coast of Florida. I will part with it for the price of the paint $125.00
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the horn mold is too big to ship and i am too far away. But I am interested in knowing your thoughts and experiences in both building the mold and the paper horn. Do you have a thread on this or have some details to share?
It really looks good and wish i could take it from you.
It really looks good and wish i could take it from you.
Making the mold was pretty interesting. I had everything except the paint in my garage. Automotive paint is not safe to work with. I have the PPE for it. Isocyanates are bad for your health. Took me about 40 hours labor for the mold. Each horn took about 25 hours of paper mache and bracket building. Total of 90 to 100 hours. I was stuck at home so I had not much else to do.
Tips. Read everything at Inlow sound carefully. Use small but good casters, I used 6. Cover inside and outside of mold with epoxy resin after you attach the wire. I used 3 plywood disks to attach the wire to. More might be better. 2 layers of wire minimum. I used a 1/2 inch threaded rod instead of 3/4". I put my 1/2" drill on top and used my variac to adjust the speed for sanding. Drill gets hot FAST so watch for that. Sanding this way makes it very round and uniform. Hardening drywall compound is cheap and sands easy. Paint mold with epoxy resin that is thickened after you have the drywall compound to exact size. After you epoxy it sand smooth, and prime with catalyzed high fill epoxy primer. It is like sanding a brick. Fill imperfections with bondo, re-primer, repeat until you say F*** this. Then sand with 600 grit and paint. After the paint is dry, sand with 2000 grit, and buff. Then apply 3 coats of Meguiars wax.
Use 100% cotton paper! Don't go cheap like I did. Glue tint is the color of the exterior.
Tips. Read everything at Inlow sound carefully. Use small but good casters, I used 6. Cover inside and outside of mold with epoxy resin after you attach the wire. I used 3 plywood disks to attach the wire to. More might be better. 2 layers of wire minimum. I used a 1/2 inch threaded rod instead of 3/4". I put my 1/2" drill on top and used my variac to adjust the speed for sanding. Drill gets hot FAST so watch for that. Sanding this way makes it very round and uniform. Hardening drywall compound is cheap and sands easy. Paint mold with epoxy resin that is thickened after you have the drywall compound to exact size. After you epoxy it sand smooth, and prime with catalyzed high fill epoxy primer. It is like sanding a brick. Fill imperfections with bondo, re-primer, repeat until you say F*** this. Then sand with 600 grit and paint. After the paint is dry, sand with 2000 grit, and buff. Then apply 3 coats of Meguiars wax.
Use 100% cotton paper! Don't go cheap like I did. Glue tint is the color of the exterior.
Thank you for posting the tips. I have gone through the site and was planning to attempt it...
Do you have any pictures of the bracket? I am not sure how to get a smooth transition from the throat to bracket and if that would affect anything?
Any pictures or threads of the complete system?
Do you have any pictures of the bracket? I am not sure how to get a smooth transition from the throat to bracket and if that would affect anything?
Any pictures or threads of the complete system?
So sad...
I come here occasionally looking for exactly this - someone who built a mold and wants to share or sell it. So sad, i would have been happy to store it and make it available to others (after i built my own).
I come here occasionally looking for exactly this - someone who built a mold and wants to share or sell it. So sad, i would have been happy to store it and make it available to others (after i built my own).