RAVENFORGE

Prototype Development Log

From Concept to Buildable Geometry

Superstrat / ASKR / EMBLA — CAD Iterations, Failure Cases, and Design Lessons

1. What This Research Log Documents

When I first drew the initial sketches, the first things that stood out were the exterior shapes of the body and headstock. However, as I repeatedly revised the production drawings, the priorities completely shifted. Before finalizing the instrument’s silhouette, I had to establish the scale, nut, fret positions, functional reference points for the bridge, string path, neck joint, and routing envelope.

The three projects varied in difficulty. With the 24-fret Superstrat, I mastered the basic rules of CAD and production drawings; with the ASKR, I encountered issues where changing a single part had a cascading effect on the entire geometry due to the 37–34-inch multiscale design and complex electronics. For the EMBLA, while using a more traditional 34-inch platform, I had to integrate the headstock, neck feel, and option compatibility into a single design framework.

2. Superstrat — Reorganizing the Design Process While Learning CAD

The first production drawing was for a Superstrat based on a 25.5-inch scale, 24 frets, a 6-inline headstock, and a Gotoh 510-series tremolo with an HSH pickup configuration. Initially, I approached the design by placing the exterior shape and component images, but as I began comparing the actual hardware measurements with the front and back views, it repeatedly became clear that even if the drawing looked correct, it could still be incorrect by manufacturing standards.

2.1 Tuners: The Posts and Screws, Not the “Shape,” Were the Criteria

The initial layout for the SG381-07 MGT began by projecting the hardware shapes onto the front and rear views. At this stage, the tuner’s exterior shape and the orientation of the buttons were clearly visible, but the post center, fixing screw center, and the left-right reversal of the rear housing—which were actually critical—were not sufficiently controlled.

Figure 1. Initial headstock projection design. A stage where attempts to align the front and rear views simultaneously led to unclear reference points for the housing and fixing screw orientations.

Instead of trying to “neatly” align the front and rear views as separate drawings, I reorganized the design so that they share the same post center and only the rear housing is mirrored to match the view’s reference.

2.2 The deep tenon and front pickup required the same space

While reviewing a deep-tenon-style structure to position the front pickup as close as possible to the edge of the fingerboard and simultaneously increase the neck’s joint area, a spatial conflict arose. We wanted the neck wood to extend all the way under the pickup, but routing the pickup required removing that same area.

Figure 4. Review of the boundary between the front pickup and the neck pocket/tenon. As the pickup is moved forward, the effective length of the neck wood decreases.

RavenForge_Superstrat_24F_REV-N_front_tenon_detail.png

2.3 Clearance and load paths were more important than the number of bolts

We also considered increasing the number of bolts to reinforce the neck joint, but due to the rear tremolo cavity, spring clamps, and front pickup routing, areas that appeared to be “empty space” were often actually unusable. The clearance check below is a verification step where the bolt arrangement and the neck-pocket envelope were overlaid separately.

Figure 5. Rear clearance check. A stage in which the body/neck-pocket boundary and machining allowance were verified first, rather than the 6-bolt arrangement itself.

REV-J_rear_clearance_check.png

2.4 If the file won’t open, it’s not a drawing—even if the geometry is correct

During Superstrat work, we repeatedly encountered issues where not only geometry errors but also the DXF structure itself was rejected by AutoCAD. In one instance, a group code not allowed in an R12 table caused the entire drawing to be discarded; later, we also encountered issues with duplicate handles and entity class separators.

Subsequently, prioritizing compatibility, we conservatively revised our file creation rules to adhere to the AutoCAD R12 ASCII structure, use simple LINE/CIRCLE/TEXT entities, perform explicit layer registration, and remove unnecessary handles and polylines.

3. ASKR — Multiscale Reveals Dependencies Between Parts

The ASKR was designed with a 37–34-inch 5-string multiscale, bridge-mounted pickups, an 18V electrical system, and expansion options in mind. Problems that were resolved around the centerline in the Superstrat became intertwined in the ASKR, involving each string’s scale line, pickup angle, bridge segment, string path, control cavity, and even battery packaging.

In particular, although the battery box appeared to be a small component, it was one of the elements that required the most repositioning. This was because it had to avoid the neck pocket, body contour, tummy cut, control cavity, and the future 3-pickup keep-out area.

3.1 As soon as we added 3-pickup expandability, the battery location became an issue again

Figure 6. Front view review after adding the 3rd pickup keep-out. It became clear that independent placement of the battery, bolts, pickups, and bridge was impossible.

RavenForge_ASKR_REV_AF_front_battery_3pickup_keepout.png

3.2 Every time the BB-04W was repositioned, a different problem arose

Moving the battery box closer to the center of the body caused conflicts with the neck/heel and wiring, while moving it toward the outer edge encroached on the belly/tummy contour and the body outline. The image below shows the steps leading to a layout that was ultimately discarded.

Figure 7. REV-AH. A layout where the battery box is too close to the lower/waist contour envelope, resulting in insufficient machining clearance.

RavenForge_ASKR_REV_AH_rear_BB04W.png

Figure 8. REV-AI. A discarded design where the box was moved to the lower bout, but the clearance between the box’s outer edge and the body contour remained unstable.

RavenForge_ASKR_REV_AI_rear_BB04W_lower_bout.png

Figure 9. REV-AJ. A relatively stable candidate design in which the components have been separated and repositioned to avoid the tummy contour.

RavenForge_ASKR_REV_AJ_rear_split_BB04_tummy_safe.png

3.3 The headstock also had to be included within the housing envelope

The headstock design wasn’t complete just by aligning the post holes. When we incorporated the HB6 series and added the actual physical envelopes of the rear housing and the key, the clearances between the headstock perimeter, the adjacent tuners, and the string path changed again.

Figure 10. HB6Y housing-safe review. This stage involves positioning not only the post center but also the actual housing envelope and string path together.

RavenForge_ASKR_REV_HB6Y_front_head_housing_safe.png

4. EMBLA — Even the “traditional 34-inch” model was not simple

Although EMBLA is a more traditional 34-inch 5-string platform than the ASKR, a different kind of trial and error arose in the process of simultaneously achieving the desired playing feel, headstock design, physical hardware, and expandability options. In particular, even when using a specific brand’s neck feel as a reference, the dimensions could not be copied directly if the number of frets, heel width, fingerboard radius, or joint method differed.

4.1 We had to map out the nut-to-post string path first

Initially, we focused on whether the tuners were balanced within the headstock’s outer perimeter. However, in practice, the priority was determining the angle at which each string traveled from the nut witness point to the post center. The thick B and E strings could not be treated with the same aesthetic symmetry as the thin D and G strings.

Figure 11. REV-I nut/string study. The actual nut-to-post path is highlighted with a cyan line to re-examine the straight pull and post placement.

RavenForge_EMBLA_002_REV_I_nut_strings.png

4.2 Tuner Bank Orientation and Rear-View Mirror Issue

Figure 12. REV-K. The stage where the geometry of each post and string line was recreated. Since some reference geometry was flipped, the bank orientation was reworked in a subsequent revision.

RavenForge_EMBLA_002_REV_K_head_tuner_geometry.png

Figure 13. REV-M rear tuner layout. We specified the “mirror rule” stating that the 2+3 bank, as seen from the playing face, appears on the opposite side in the rear view.

RavenForge_EMBLA_002_REV_M_rear_tuners.png

5. Recurring Patterns of Failure Across Three Projects

Although the projects differed, the causes of failure were surprisingly consistent. Most began with the assumption that “if I put parts that fit independently into a single instrument, the whole thing will fit.” In reality, the position of a single part required changes to the surrounding machining, the structure on the opposite side, and even the work sequence.

6. Reasons for Separating Production Drawings and Work Templates

Initially, we attempted to include all information in a single master drawing. However, router templates do not require wiring plans, and head templates do not require information on the rear control cavity. A drawing is not necessarily better simply because it contains more information; a drawing that retains only the information necessary for each work stage is safer.

• Master Drawing — Manages overall reference geometry and relationships between parts
• Neck / Head Template — Focus on outline, nut, tuners, and truss/reinforcement centers
• Body Routing Template — Focus on the neck pocket, pickup routing, and bridge reference
• Rear Template — Focus on the cavity, tremolo/spring, or battery route
• Pickguard Template — Retains only the actual cutting outline and openings
• 1:1 Print Template — Verify print scale, tile overlap, and crop marks separately

7. Current Conclusion — A drawing is a hypothesis, not an answer

Even if all interferences are eliminated in CAD, it cannot be assumed that actual production will be successful. Variations in wood, tolerances of router bits and jigs, manufacturing deviations in hardware, and assembly accessibility can only be verified on an actual prototype. Therefore, the current drawing is not the final answer but rather the most refined hypothesis established prior to production.

In the next verification phase, we measure the actual neck-pocket fit, bridge/string alignment, tuner clearance, reinforcement operating range, pickup routing depth, cavity wall thickness, battery accessibility, center of gravity, and workability, and incorporate these findings into the drawing revision.

“The drawing is not the instrument.
It is a hypothesis about the instrument.
The prototype is the experiment.”