3k Custom Carabiner (SOMETHING NEVER DONE!)Blind
in
Mechanical Engineering
held by
brianh9
Last seen:
Contest Closed
-
Open
-
Choosing Finalist
-
Ended
Description:
Mechanical CAD Engineer Needed — CNC Aluminum Carabiner (Skeletonized Load‑Bearing Design)Service Category: Mechanical Engineering / CAD Design
Industry: Product Design / Hardware / Outdoor & EDC
Manufacturing Method: CNC Machining (Aluminum)
⸻
Project Summary
I am developing a custom CNC‑machined aluminum utility carabiner where the brand mark “3K” is structurally integrated into the body as a skeletonized, load‑bearing element.
This is not jewelry, not a render-only project, and not concept art.
The goal is manufacturable, mechanically sound hardware suitable for real-world utility use (non‑climbing certified).
⸻
Key Design Challenge
The core challenge — and what makes this project unique — is that the “3K” lettering replaces traditional webbing in the carabiner body and must:
• Carry load as part of the primary structure
• Maintain proper load paths and stress distribution
• Avoid stress risers and thin sections
• Be optimized for CNC machining
The logo is functional structure, not decoration.
⸻
Scope of Work
• Develop production‑ready CAD based on an established design brief
• Model:
• Main carabiner body
• Gate assembly (screw‑lock)
• Integrated skeletonized “3K” geometry
• Apply:
• Proper wall thickness
• Fillets and radii
• CNC tool access and manufacturability constraints
• Prepare deliverables suitable for:
• Prototyping
• Small‑batch production
⸻
Deliverables
• STEP (.step) files
• Native CAD files (SolidWorks or Fusion 360 preferred)
• 2D manufacturing drawings including:
• Material callouts
• Tolerances
• Finish specifications
⸻
Technical Requirements
• Proven experience with CNC‑machined aluminum parts
• Strong understanding of:
• Load paths
• Stress concentrations
• Fillets, radii, and edge conditions
• Mechanical hardware tolerances
• Familiarity with:
• 7075‑T6 or 6061‑T6 aluminum
• Anodized finishes (Type II / Type III)
⸻
Manufacturing Parameters
• Material: 7075‑T6 aluminum (preferred)
• Process: CNC machining from billet (no casting)
• Finish:
• Matte black hard anodized body
• Contrasting polished or chrome “3K” feature (masked or insert)
Wants:
1. Design & Aesthetic ExecutionWeight: 20%
Style & Visual Language
• Overall form must feel:
• Technical
• Minimal
• Sport‑industrial
• Influences aligned with:
• Rick Owens (brutalist, monolithic)
• Oakley / Nike ACG (functional, engineered, outdoor)
Color & Finish
• Primary body: All matte black
• Finish must be specified as:
• Hard anodized aluminum (Type II or Type III)
• The “3K” logo:
• May remain raw aluminum or chrome
• Must contrast clearly against the black body
• No chrome or gloss finishes on the main body
Surface Quality
• Smooth, continuous curvature
• No unnecessary facets
• No sharp visual transitions
• Consistent edge radii throughout
⸻
2. Integration of the 3K Logo (Critical)
Weight: 25%
The “3K” must function as structural skeleton, not decoration.
Requirements
• The “3” and “K” are:
• Load‑bearing elements
• Part of the primary force path
• Logo geometry replaces traditional webbing
• No applied or engraved logos
Evaluation Points
• Stroke thickness consistency
• Structural continuity through the logo
• Absence of weak or dead‑end geometry
• Smooth load transitions through the “3K”
🚫 Disqualification if:
The logo is purely cosmetic, engraved, or applied after the fact.
⸻
3. Dimensional & Block Definition
Weight: 15%
Overall Block Dimensions (Target Ranges)
• Height: 75–85 mm
• Width: 45–55 mm
• Body thickness (Z): 9–11 mm
Submissions must clearly define:
• Overall envelope
• Section thicknesses
• Proportional balance
Cross‑Section Attributes
• Rounded or oval cross‑section preferred
• No flat, knife‑edge profiles
• Minimum wall thickness:
• ≥ 6 mm in load‑bearing areas
• ≥ 4 mm in non‑critical regions
⸻
4. Mechanical Attributes & Structure
Weight: 20%
Load Path Logic
• Clear explanation (or obvious geometry) showing:
• How load travels through the spine
• How it transfers through the 3K skeleton
• Gate must not be load‑bearing
Stress & Safety Considerations
• No sharp internal corners
• Minimum internal fillet radius:
• ≥ 2.0 mm
• External edge radii:
• ≥ 1.0 mm
• No thin necks or choke points
⸻
5. Gate, Bolt & Hardware Placement
Weight: 10%
Gate Design
• Screw‑lock or threaded sleeve design
• Gate modeled as a separate component
• Adequate clearance:
• ≥ 0.5 mm between moving parts
Bolt / Pivot Location
• Pivot axis clearly defined
• Pivot positioned in:
• Structurally reinforced zone
• Non‑logo critical stress area
Headlift / Gate Opening
• Gate opening must allow:
• Easy key / strap insertion
• No interference with skeleton geometry
• Headlift placement should:
• Avoid stress concentration at hinge
• Maintain smooth exterior silhouette
⸻
6. Layering & Manufacturing Logic
Weight: 10%
Part Breakdown
• Clear separation of:
• Main body
• Gate
• Lock sleeve
• Fasteners
• No unnecessary part count
CNC Manufacturability
• Geometry must be:
• CNC‑machinable from billet
• Accessible by standard tooling
• Avoid:
• Deep blind pockets
• Undercuts without justification
Finish & Masking Logic
• Clear identification of:
• Anodized surfaces
• Masked / raw or chrome “3K” surfaces
⸻
7. Presentation & Documentation
Weight: 5%
Submissions should include:
• Orthographic views
• Section views (preferred)
• Clear depiction of:
• Dimensions
• Structural intent
• Assembly logic
Extra credit for:
• Exploded view
• Simple load‑path diagram
⸻
Overall Evaluation Priority Order
1. Structural integrity & logo integration
2. Manufacturability (DFM)
3. Dimensional discipline
4. Aesthetic clarity
5. Documentation quality
⸻
Automatic Disqualifiers
• Decorative‑only logo
• Non‑manufacturable geometry
• Jewelry‑style proportions
• Render‑only submissions with no dimensional logic
• Ignoring blacked‑out body requirement
⸻
Ideal Winning Entry (Summary)
A clean, all‑black, CNC‑machined carabiner where the 3K logo is a visible, functional skeleton, with smooth load paths, disciplined dimensions, and factory‑ready geometry.
Proposal Requirements
Please include:
1. Examples of relevant mechanical / CNC projects
2. CAD software used
3. Brief description of experience with aluminum hardware
4. Confirmation that you understand this is functional hardware, not decorative
Don't Wants:
-Jewelry design-Concept‑only industrial design
-Blender‑only or render‑only work
Ask for Sample:
Please finish the design as a sample. The best designer will complete the project.
Company Logo:
Yes
Software:
- 2D & 3D Modeling Solidworks (Latest)
- Fusion 360 (Latest)
- STEP (Latest)
Prepaid PrizeEntries
#12 carbiner frame v0
by souhailb
Hidden design
Download Files
#11 carabiners with 3K branding
by arslanm
Hidden design
Download Files
#10 Sleek aluminum carabiner with 3K logo
by arslanm
Hidden design
Download Files
#9 3k-consept05
by alirezaemamian
Hidden design
Download Files
#8 Carabiner (Only Concept 1)
by adnan313
Hidden design
Download Files
#7 3K proof of concept
by MécaCim
Hidden design
Download Files
#6 3K Structural Truss - CNC Optimized (Tactical EDC)
by tirthborda
Hidden design
Download Files
#5 3K Master1
by wenzel_wu
Hidden design
Download Files
#4 3k-consept04
by alirezaemamian
Hidden design
Download Files
#3 3k-consept03
by alirezaemamian
Hidden design
Download Files
#2 3k-consept02
by alirezaemamian
Hidden design
Download Files
#1 3k-consept01
by alirezaemamian
Hidden design
Download Files
Discussion
CONTESTANTS: This is my first time using CAD crowd and the world of CAD design is still very brand new to me. I prematurely jumped the gun on a project design that is entirely is way too complex for me and outweighs my current means (being a new business owner). I need more time to strategize, revise and attack this project under better circumstances. I will be returning to do this project with CAD Crowd, just at a later time. I apologize, I hope to work with some of you in the future.
any specific value of load ?
After reviewing your requirements we can advise and produce all manufacturing dwgs and recommendations. I would suggest reviewing your prize as it does not reflect the time and effort required to satisfy your full requirement needs.
Is there any special meaning "3K"?
I have been working in aerospace and optical instrument industry for 20+ years. Have designed +100 aluminum parts. This is a very interesting project with detailed request. In my opinion, your prize does not match the effort and time needs to spend on it by an experienced designer.
Similar Contests on Cad Crowd
Hand Drawn PDF to CAD and 3D
Convert hand drawn PDF to CAD and 3D as follows.
Gasket - CAD
Spacer - CAD and 3D
Tube - CAD and 3D
Correct scaling as necessary.
Deliverable's include the following file types:
DWG
PDF
STEP
ANSI size C sheet.
Mechanical SolidWorks CAD Project
We are looking for a process diagram and a solidworks drawing of a complete pump station. All of the detailed submittal sheets will be emailed. A complete understanding of mechanical equipment will be needed in order to complete these drawings. Please feel free to ask questions. Examples can be provided.
For this Job the pump station must fit underneath the cooling tower. We are providing the cooling tower stand as well. The height of the stand will be defined by the tank height along with the cooling tower return line (bottom outlet) being routed into the top of the tank. The pump station can extend outside of the cooling tower stand in the Length dimension, but must fit in within the Width.
We would like to identify a couple of resources to work with long-term on multiple projects. Let me know if interested and I'll send the submittal sheets so you can provide an accurate quote.
Thanks,
Jason
Chirp
Mechanized tablet holder for commercial vehicles.
Rough draft completed already. Need to hire competant mechanical / electrical designer to complete project.
Tray palletizer
Design a simple device for stacking trays ..this is for stacking the domed labels to dry.. it must lower the tray gently enough not to spill the resin away from the domed labels as shown on the attached graphic.
Design a mini excavator similar to KubotaU-10-3
We are interested to manufacture mini excavator with 360 degree suwivel similar to Kubota U-10-3 and aother company's product in the market. The designer should be able to support till the completion of the project
brianh9
Buyer