Recently I put together a vacuum bagging system for gluing up the composite sandwich braces in the ABG. You can see pictures of the process in the web album.

I’ve also built a vacuum press for gluing the braces on the top - stay tuned for that.

Luthierie/Guitar Building, Acoustic Bass Guitars, Workshop | 1 Comment »

Because the bracing of the new basses is so experimental, I need to load test the top to test deflection under string tension. To do this, I made a dummy top out of the real material, braced it, and mounted it in a frame that simulates the perimeter of the body and neck block.

I also had to make a bridge, because the bridge adds stiffness to the top and distributes the load of the strings. I made this from a scrap of really nice birdseye maple from Warmoth’s wood trailer. A little bright against the top, but I like it. I think it will look good once it has a saddle and strings on it.

Instruments, Luthierie/Guitar Building, Acoustic Bass Guitars | No Comments »

Have a question or comment? Then hop on over to the new BW Bass Forum!

Of course nothing beats Talkbass for general bass discussion, but I hate to spam their board talking about my own stuff.

Enjoy!

Edit:

I scrapped the ABG forum when I found that another good ABG-only forum already exists at The Dudepit.

Meta | 10 Comments »

I’ve got the laminate materials for the first three basses, and I’ve settled on a bracing design for the tops. The next step will be to start building the body mold and side template so I can start making some sawdust. I’ve been holding off on this step for a while because I really wanted to make the master patterns for these parts on one of the CNC’s at work, and I had to get a couple of other work projects out of the way first.

Now things are looking good to make the patterns this week. I’ll update the comments with more progress info as it happens.

Also, be sure and check out the new links page, as well as the pictures I took on vacation of Rick Turner’s Renaissance Guitar Company and Gryphon Strings.

Instruments, Acoustic Bass Guitars | 1 Comment »

One of the best characteristics of a brace for an acoustic guitar top is a high stiffness-to-weight ratio. The less mass the top and braces have, the easier it is for the string’s energy to set it in motion and create sound. At the same time, the top and braces need to be strong enough to withstand the 150 so pounds of string tension without collapsing.

In the Big Red ABG, I used braces with a sandwich of graphite and balsa (at far right in the picture above). This design was very stiff and light, but because I used standard 1/2″ square balsa struts, with the grain running lengthwise, they were prone to splitting top-to-bottom and required quite a bit of reinforcement at the ends. More recently I tried end-grain balsa sandwiched between layers of phenolic laminate. This was light and resistant to splitting, but not quite as stiff as I wanted.

Finally, I came up with a 5-layer sandwich for the braces in the new acoustic bass guitars: Phenolic laminate, carbon fiber tissue, aluminum honeycomb, more carbon tissue, and unidirectional carbon fiber. This combination is very stiff, stable and light. A nice benefit of this design is that the top layer of the sandwich is the top of the instrument itself, so the mass added by the braces is just that of the honeycomb and carbon fiber on the bottom of the sandwich!

Instruments, Luthierie/Guitar Building, Acoustic Bass Guitars | 3 Comments »