Mechatronics Engineer to Productize Humidity-Controlled Card Splitting & Bonding Rig

I am developing a small precision fixture for controlled delamination and rebonding of standard trading-card laminates for restoration research and destructive testing. Standard samples are approximately: 63 mm × 88 mm 0.30 mm thick Coated, printed, multilayer paper/cardstock Some samples may include holographic or foil layers The current process used by practitioners is largely manual: condition the card with humidity, initiate an internal split with a precision blade, separate the laminate, prepare the retained surfaces, align the layers, apply a controlled adhesive film, and press the assembly flat. I have already created an early prototype concept, OpenSCAD/STL files, printed PLA fit-test components, an initial BOM, an assembly guide, and a proposed humidity-controlled workstation. I need an experienced mechanical or mechatronics engineer to audit the concept, correct the design, prototype it, characterize the process, and turn it into a safe and repeatable benchtop system. This is not just a 3D-modeling assignment. I am looking for someone who can own the mechanical engineering, tolerancing, testing, and iterative development. Proposed system The system will likely include two separate stations. 1. Humidity-controlled splitting fixture Potential components include: Gasketed environmental enclosure Controlled humidified-air inlet with condensate management Temperature and relative-humidity sensors Precision linear rail and low-speed feed mechanism Replaceable, fully guarded blade cassette Commercial disposable microtome or similar precision blades Metal guide and reference surfaces Micrometer or shim-based blade-height adjustment Force sensing or motor-load monitoring Microscope or camera visibility of the split line Limit switches, interlocks, and emergency stop Data logging for humidity, temperature, speed, position, and force A hybrid process may be tested where a blade initiates the first few millimeters and synchronized rollers propagate the separation. 2. Alignment and bonding fixture Potential components include: Three-point registration nest for 63 × 88 mm layers Removable alignment cassette Controlled adhesive-film application Flat metal caul plates Measured-force press Optional controlled platen heating and cooling Temperature sensing near the laminate interface Repeatable pressure, dwell-time, and cooling cycles Splitting and bonding should remain separate processes. The goal is to avoid bonding while the sample contains excessive moisture. Scope of work Phase 1: engineering audit Review the existing CAD, STL files, printed components, BOM, and process assumptions. Identify: Incorrect dimensions or interfaces Missing components Tolerance and alignment risks Blade-deflection and blade-wandering risks Rail, lead-screw, and carriage-layout issues Moisture and condensation risks Pinch, cutting, electrical, and humidity-related safety risks Components that should be machined rather than printed Better commercially available mechanisms or components Deliver a written design-review summary and recommended architecture before substantial redesign work begins. Phase 2: corrected mechanical design Create a robust parametric CAD assembly for the splitting station. The design should include: Baseplate and mounting layout Linear-motion system Card sled and replaceable pusher Precision metal guide plates Adjustable blade cassette Complete blade guard Card-path alignment features Motor and lead-screw mounts Bearing supports Limit-switch mounts Sensor and camera mounts Enclosure interfaces Condensation-resistant air-routing components Easy disassembly, cleaning, and blade replacement The printed parts should be designed for PETG or another appropriate production material. Precision, reference, and load-bearing surfaces should use aluminum, stainless steel, or another suitable material. Phase 3: controls and instrumentation Design or recommend a simple control architecture for: Low-speed stepper motion Adjustable feed rate Homing and travel limits Emergency stopping Relative-humidity and temperature monitoring Humidifier control Fan control Force or motor-load monitoring Fault detection Data logging ESP32-based controls are acceptable, but I am open to a better recommendation. Any mains-powered humidifier should remain electrically isolated from the humid chamber. The system should fail safely if a sensor disconnects, condensation is detected, or a travel limit is reached. Phase 4: bonding and alignment station Design a separate fixture capable of: Aligning two flexible 63 × 88 mm laminate layers Holding alignment during transfer Applying a thin, consistent adhesive layer or pre-cast adhesive film Pressing the sample between flat caul plates Measuring or controlling applied force Optionally controlling platen temperature Cooling or drying while pressure remains applied Avoiding embossing, squeeze-out, sliding, and uneven thickness Adhesive selection will be experimentally validated on sacrificial samples. The engineer does not need to be a conservation chemist, but experience with laminates, adhesives, coating, web handling, paper products, or composite bonding would be highly valuable. Phase 5: prototype testing and optimization Develop a structured test plan covering: Card-thickness variation Guide clearance Blade height and angle Blade type Feed speed Relative humidity Conditioning time Temperature Cutting or separation force Split-plane consistency Fiber tear-out Surface and foil damage Final thickness Flatness Bond strength Edge visibility Delayed curl or separation Initial testing will use worthless, permanently marked samples. Different card constructions should be treated as separate process families rather than assuming one universal setting. Required deliverables Final deliverables should include: Complete parametric CAD source Native SolidWorks files preferred, or another agreed professional CAD format STEP files for all assemblies and machined parts Print-ready STL or 3MF files Dimensioned manufacturing drawings Assembly drawings and exploded views Hardware and fastener schedule Complete BOM with manufacturer part numbers and suppliers Wiring diagram Control-system architecture Firmware source code, where applicable Calibration procedure Blade-replacement procedure Assembly instructions Safety and guarding recommendations Risk/FMEA-style review Prototype test protocol Test-data templates Recommended production materials and processes DFM recommendations for a small production run Revision-controlled source files and documentation All custom interfaces must be based on measured hardware rather than assumed dimensions from generic online listings. Acceptance criteria A successful prototype should eventually demonstrate: Repeatable alignment of 63 × 88 mm samples Adjustable and measurable guide clearance Adjustable blade position with metal reference surfaces Smooth, controlled low-speed feed No exposed blade during normal operation Safe blade replacement with the machine disabled Stable and measurable chamber humidity No direct mist or droplets reaching the sample Logged process parameters Repeatable operation across multiple sacrificial samples A bonding fixture that maintains alignment during pressing Complete documentation sufficient for another engineer to reproduce the machine The first milestone is not a cosmetically perfect restored sample. It is a mechanically sound, measurable, safe, and testable platform. Ideal candidate Strong candidates will have experience in several of the following: Precision mechanical fixture design Mechatronics Linear motion and stepper-driven systems Small-machine or laboratory-equipment design SolidWorks or equivalent parametric CAD Tolerance stack-ups and GD&T 3D printing and machined-part integration Blade, slitting, skiving, microtome, or converting machinery Paper, film, foil, laminate, adhesive, or composite processing Environmental or humidity-controlled enclosures Load cells and force measurement ESP32, Arduino, or embedded controls Design for manufacture and small-batch production Machine guarding and safety interlocks Experience with converting equipment, book or paper conservation equipment, medical/laboratory instruments, precision cutting, web handling, die cutting, or laminate testing would be especially relevant. How we will work I am technical and can move quickly. I can: Print prototypes locally Purchase off-the-shelf components Assemble and test revisions Provide measurements, photos, microscope images, and test data Work with Codex or Claude Code on firmware and documentation Ship components or samples when necessary Provide rapid feedback after each revision I expect the engineer to: Challenge weak assumptions Explain major design decisions Work in documented milestones Maintain organized, editable source files Provide regular progress updates Avoid designing around unverified component dimensions Prioritize safety, measurement, and repeatability over appearance I prefer an iterative engagement beginning with a paid design audit, followed by prototype development and testing. This could become an ongoing product-development relationship if the initial work goes well. Important use and disclosure requirement This fixture is intended for disclosed restoration research, destructive testing, and process characterization. Development samples will be worthless and permanently identified as altered. The project is not intended to help reconstructed cards evade authentication, grading, or disclosure requirements. Please include in your proposal Please answer the following: What similar precision fixture, cutting, laminate, laboratory-equipment, or mechatronics projects have you completed? Which parts of this system would you machine rather than 3D print, and why? How would you control and measure a blade plane inside a laminate approximately 0.30 mm thick? How would you prevent condensation from reaching the sample inside a humidity chamber? What CAD and embedded-control tools do you use? Can you provide native CAD, STEP, drawings, BOM, wiring documentation, and source code? How would you structure the first two or three project milestones? Please include relevant portfolio examples and your estimated availability.