FEATURED CASE STUDY / MANUFACTURING & TOOLING
Multicam tool fork: redesigning a part that kept breaking
The original part kept breaking. I rebuilt its geometry in Fusion, changed the material to TPU, and put the printed replacement to work in the machine it was made for.
The problem
Brittle original tool forks, recurring breakage, and a reported replacement price of $45–$65 each.
My response
Reverse-engineer the curved geometry, make targeted adjustments, and print a TPU replacement on my Voron V0.2.
The reported result
Firm retention after a 90-day trial, survival of the impacts described in my report, and a stated $35 replacement cost.
Historical project figures from my September 15, 2023 report. They are not current prices or a fully burdened cost study.
Professional notes
From a maintenance problem to an implemented component
This project brings together an observed workplace problem, nontrivial geometric reconstruction, a change in material behavior, additive manufacturing, and a field trial. The photographs and videos connect the replacement part to its actual machine application.
The original September 2023 account describes a 90-day trial and a $35 replacement versus an original $45–$65 price range. The source is my contemporaneous report, not an independent cost or reliability audit.
A small component with a real job
The fork sits at the interface between a CNC tool rack and its tool holder. Its shape is functional: the opening must receive and hold the tool in the arrangement shown in the machine footage. A replacement therefore has to do more than resemble the original when placed on a workbench.
My original post describes the ABS forks as brittle in this application and prone to breaking. It also records replacement prices of $45 to $65 per unit. Instead of simply ordering another of the same component, I reproduced the geometry and explored a different material and fabrication route.
Reverse engineering without convenient square edges
I modeled the original in Fusion. In the project post, I specifically called out the lack of square edges as one of the harder aspects of the work. The curved opening, mounting arrangement, relieved regions, and changing outline had to be represented together, rather than treated as an arbitrary decorative shape.
After reconstructing it, I made minor adjustments and produced the replacement in TPU. The comparison photograph shows both the inherited overall form and differences in the details. The later dimensioned drawing records the component in multiple views.
The material change was central
This was not only a change from a purchased part to a printed one. The documented change was from ABS to TPU, with the latter's flex being the feature I highlighted after use. I printed it on my Voron V0.2; the original post records 15% infill and a 0.2 mm layer height.
My report emphasized two observations: the grip on the tool remained firm after the trial, and the flexible replacement survived multiple direct spindle impacts. Those are application-specific observations, not a claim that TPU is the right replacement for every CNC component or every tool-changing system.
What I reported after 90 days
On September 15, 2023, I reported that the installed fork still held the tool as firmly as it did on the first day. I also reported a flat $35 per-unit replacement cost. Relative to the $45–$65 original-part range in the same post, that is a stated difference of $10–$30 per component.
The valuable result is the complete practical sequence: notice the failure, reconstruct the part, alter it, manufacture it, install it, and return with observations from use. The record does not supply machine-cycle counts, a formal test protocol, or a measured long-term service life, so this page does not invent them.
Files that keep the work inspectable
The repository contains ToolFork_v1.3mf, ToolFork_v2.3mf, and ToolFork_v2_add4mm.3mf. These are separate saved variants within the same project, not three projects. Their names are preserved without assuming which one corresponds to every installation shown.
Credits & project records
Original machine/component: Multicam. Reverse engineering, adjustments, printing, and the project account: Michael Pytlowany. Printer platform: Voron. This is an adaptation of an existing part, not authorship of the original machine.
The four photographs and two videos accompany the same September 15, 2023 Jerky_FPV post. The silent website copies retain the original video sequence without background audio. The native drawing is ToolFork Drawing v4, issued October 4, 2023.
Price, retention, impact survival, and trial duration are reported in the original first-person account. The post also offers an environmental explanation for deterioration; no controlled materials investigation is supplied, and that explanation is not treated here as an established mechanism.
The original caption says "7 parameters." That wording is not silently converted to a verified wall/perimeter count. Material grade, full slicer profile, test protocol, and machine-specific safety validation are not provided as part of this case study.
FROM THE ORIGINAL PROJECT POST
From printer bed to tool rack.
Two views of the same project: making the replacement and seeing the machine use it.
PART DETAILS
The replacement, up close.
FROM THE TOOL CRIB