Open Source, Open Baffle Part II - Drivers, Baffles, Wire
The baffles arrived for my project the other day. My good friend and all around man who can do anything cut and drilled them for me, leaving me to sand them a bit and put two coats of wipe on polyurethane.
To bolt the baffles to the frames requires longer bolts than what was used to put the frame together. There are 24 bolts total.
To mount the baffles to the frames I used a lower profile screw, copper washers, and 80/20 m6 threaded T-Nuts for the aluminum channel. You will need 24 of each.
- 24 copper washers - McMaster-Carr $7.72 for a box of 25
- 24 M6-1 30mm long Alloy Steel Flanged Button Head Screws McMaster-Carr
- 24 80/20 m6 threaded T-Nuts
The washers go underneath the screw head between the screw and the baffle. Why copper? Copper has a pleasant sounding resonance frequency and I thought it couldn't hurt. I like it better than brass. For now, I let the back of the baffles have direct contact with the aluminum frame. This could change as I might add some vibration damping material between the baffle and frame later. It could be in the form of washers to go around the bolts, or a strip of material that would sit between the top and bottom bolts, on the back of the baffle.
For the drivers, each woofer requires 8 bolts, and each full range driver requires 6, so 44 bolts total to mount the drivers to the baffles. Unfortunately the full range drivers have a smaller mounting hole, so they will need smaller mounting bolts and T-nuts.
First the drivers. You will need the following bolts and T nuts:
- 32 M6-1, 16mm long socket cap screws from McMaster-Carr. They come in packs of 50 for $8.24. I used the left overs from the frame build. They will work, but if you have to order, you could go up to 20mm in length.
- 32 M6 T-nut inserts for wood, also at McMaster-Carrr. A Pack of 50 is $9.50
- 12 M4 T-Nut inserts for wood - a pack of 100 is $13.60. You might be better off finding these at a local hardware store.
- 12 M4 20mm long socket cap screws - A box of 100 is $14.12 from McMaster Carr. You might be better off finding these at a local hardware store.
Close up view of the back side of the baffle. The T-nuts are hammered into the mounting holes. The bolt goes into the front side, and the two are pulled towards each other when tightened. It works very well for securing the drivers.
The back side of the baffle with the Eminence Alpha 15A mounted
Three baffles with mounted drivers. Damn I wish I had all the parts to mount these today...
The frame to which the baffles will be mounted.