Manufacturing Thor: Part 1

I promised to keep you all updated on Thor while we are producing the first batch. There’s just so much on my plate these days that I find it hard to find time to write. But hey, better late than never. It’s about time to take action! There’s a lot I’d like to share that, given the unique, non-traditional construction techniques used, may be of interest to many. And, I’m quite proud of it! There’s just nothing like it.

Prototyping is one thing and manufacturing is another thing. There are design decisions that must be made in order to simplify manufacturing and achieve consistent, high-quality results. Thor evolved over the years from the Alpha prototype a decade ago, which was never intended for mass production. For manufacturing, some aspects needed to be redesigned. Here’s a retrospective review of what has transpired, as well as a log of incoming updates as they happen, including successes and mistakes.

Here’s the first of a multipart series.

Part 1: The Back Cover

The back cover is made from 3 layers of Grade A 3K 200gsm Carbon Fiber Twill.

Here’s the original Thor prototype:

The back cover spans the entire body and is held in place by powerful magnets. Strong magnets ensure that the back cover does not easily come off.

We lay up carbon-fiber using our trusted body fiber glass mold. A huge advantage to using molds, compared to traditional guitar construction methods, is that you get consistent, repeatable results every time. I suppose the same can be said of CNC’d wooden bodies.

Side note: Reviewing this picture below, perhaps it’s time to make a new mold! But, hey, it’s still doing its job quite admirably.

Using 2-part clear epoxy, the first two carbon-fiber layers are laid-up over the mold. We used to vacuum bag the carbon-fiber laminate during the lay-up process to remove unwanted voids and bubbles. Vacuum clamps down the carbon fiber fabric to properly hug the mold. Later on, as we gained more proficiency using carbon-fiber, we skipped the vacuum bagging step. Instead, after mixing the two-part epoxy, we wait until the resin is suitably tacky before laying-up the first layer. Timing and speed are essential, so I suppose this technique is not applicable to large or elaborate constructions that require a lot of time to complete. But for our specific case, we’ve had excellent results.

After trimming the edges, we have these nice back covers:

Carbon-fiber strips reinforce the back cover for added rigidity and to ensure that the bottom is completely flat where it needs to be. Carbon-fiber tubes hold magnets in place. The third and final layer of carbon fiber is laid-up up on the underside, completely covering the protruding carbon-fiber tubes.