Q1 Overview

Inspection

Blueprints are essential documents in machining, detailing the size, shape, and dimensions of parts. Solid lines represent visible features, while dotted lines indicate hidden features. Key components of a blueprint include:

Parts List (PL): Contains part numbers, names, revision information, and specific data.
Drawing and Model Information: Includes sheet/model numbers, sheet count, and specifications for assembly.
Annotations: Flag notes, geometry-related notes, and general tolerances.
Other Features: Title blocks, review blocks, picture areas, orthographic (2D) and isometric (3D) views, and detailed tolerances.

Blueprints also outline part locations, quantities, and required specifications for precise manufacturing and assembly processes.

GD&T Basics (Geometric Dimensioning and Tolerancing)

GD&T uses standardized symbols to communicate the allowable variation in part size and form. It ensures critical features meet functional and interchangeable requirements. Key concepts include:

Tolerancing: Defines acceptable variations; overly tight tolerances can increase costs.
Datums: Specify reference points or surfaces for controlling degrees of freedom.
Functional Dimensions: Arranged to highlight features critical to the part's operation.
CTQ (Critical to Quality): Limits are established for essential features to maintain performance.

A well-designed GD&T system ensures clarity for the machinist, reducing errors and improving manufacturing efficiency.

Parts List and Usage

The Parts List (PL) is a critical tool in manufacturing and assembly, which includes detailed information about each component, such as:

Part Numbers and Names for identification.
Revisions and Notes for updates and critical instructions.

PCM ( Photo Contact Master)

PCMs are particularly valuable because they provide a 1:1 scale representation of parts, enabling precise comparison between the drawing and the physical part. To maintain accuracy, PCMs must be stored in a temperature-controlled environment, as the material can shrink or deform due to temperature fluctuations. Such deformations can distort the measurements on the sheet, leading to inaccuracies when comparing it to the actual part. By preserving the integrity of the PCM, machinists can reliably use it to confirm:

Dimensions: Ensuring all measurements align with specified tolerances.
Shape and Features: Verifying that the part's geometry matches the design.
Fit and Orientation: Ensuring the part will integrate correctly into its assembly.

Signing In a Part for Inspection:

we familiarized ourselves with the process of signing in a part for inspection, which you will need to do when you are submitting a first part check if the inspector is not available at the time. Here’s a summary of the steps we covered:

To start, you sign in your part to be placed on the inspection waiting list.
- Required Information:
  - Date
  - Name
  - Time
  - Work Order #
  - Operation #
  - Part Number
  - Work Area
Once signed in, the inspector reviews the part and returns it once the inspection is complete.

(No pictures were taken due to this being prior to the making of my portfolio)

Manual Mill and Manual Lathe

Manual Mill:

I learned how to tram the mill to ensure the vise was properly aligned, using a dial indicator and carefully adjusting it with a mallet. I gained experience securely clamping a block, facing it with a face mill, and deburring edges for smoothness. Rotating and machining all six faces taught me how to maintain perpendicularity and measure accurately with calipers to stay within a 0.010" tolerance. I also practiced cleaning the vise between rotations to prevent errors and completed machining along the Y-axis, which improved my confidence and proficiency in using the manual mill.

Manual Lathe:

I learned to set up a 3-jaw chuck, securely hold a part, and face a cylinder using a carbide insert with the automatic feed for consistent cuts. Zeroing the axes and making incremental diameter cuts taught me precision and the importance of frequent measurements with calipers. Using a 4-jaw chuck, I practiced centering a part with a dial indicator, adjusting the jaws to achieve a 0.002" tolerance. Facing and performing final diameter cuts on the lathe enhanced my understanding of both chuck types and improved my skills in precision machining.

If you would like to know more, visit the dedicated page!
https://sites.google.com/view/laythsportfolio/manual-challenges

Waterjet and Deburr

Waterjet:

My time on the waterjet was an incredibly fun and hands-on experience! I learned how to set the home position by moving the nozzle to the corner and using a gauge pin to ensure precise alignment. After verifying the material using the work order and cross-checking the sheet markings, I prepped the aluminum by removing the plastic film and loading it onto the waterjet with a suction cup. I secured the sheet with a vice, started the cutting process, and sprayed off the sand post-cut. I also broke off the tabs, cleaned the parts, reamed the holes with two different size reamers, and refilled the garnet using 55 lb bags. Working with titanium parts, I learned to carefully handle sharp edges and applied pink lubricant during reaming to prevent wear. I finished by replacing materials, setting up the machine for new cuts, and loading more programs.

Deburring:

Deburring was the most enjoyable part of the process! I started with the whirly tool to deburr inside the holes, then used a 90-degree deburring tool with fine-grit sandpaper to smooth down tabs. A DA (Dual Action) sander helped remove surface burrs, while an inline sander added the final touches. This hands-on work gave the parts a smooth, professional finish and was incredibly satisfying.

For more details, go to https://sites.google.com/view/laythsportfolio/waterjet

2D Challenge- Iphone Case

Creating a CAD Model

I began by measuring the dimensions of an iPhone 15 Plus and creating a sketch in Fusion 360. Using tools like the Flange and Bend features, I developed the foundational design, which included the edges of the case bending upward to form its shape.

Setting up the CAM Process

Next, I prepared the CAM setup for a waterjet machine. This involved selecting a 2D cutting program, defining the cutting paths for holes and borders, and simulating the cuts to verify alignment and precision for when the waterjet became available.

Simulating the Process with Paper

With the waterjet machine unavailable, I simulated the process using paper. I cut out an enlarged version of the case, ensuring the design matched the intended dimensions and contours.

Shaping the Paper Model

Using a box cutter, I crafted precise holes for buttons, ports, and speaker areas. After marking bend lines on the paper, I folded the edges with the help of a ruler to replicate brake forming, achieving a realistic simulation of the metal bending process.

Final Assembly

Once bent, I taped the corners of the paper model to maintain its shape, mimicking the final assembly of the iPhone case. This hands-on exercise provided insights into the fabrication and assembly process.

For more details about my 2D Challenge, go to:

https://sites.google.com/view/laythsportfolio/2d-challenge

CNC Mill 3 Axis

CNC Maintenance: Mill Tools, Tool holding:

Tool Selection and Setup:

My experience with the tool selection process was both technical and hands-on. I learned to use the MDI screen to select tools, ensuring accuracy by cycling the machine and inspecting each tool for wear or damage. For example, I identified wear on Tool 3 (a 375 3-flute end mill) and discoloration on Tool 4, which we flagged for replacement. After replacing tools, I measured the tool length with calipers to confirm it matched the documentation.

Building tools in collet-style holders taught me how to remove worn tools, install new ones, and ensure proper clearance between the tool’s flutes and the collet. I also learned how to use a shrink-fit tool holder by heating the holder, inserting the tool, and cooling it to create a precise fit. Comparing shrink-fit and collet-style holders gave me insights into their applications, with shrink-fit providing high precision for demanding operations and collet-style being more versatile and user-friendly. This process helped me understand the importance of proper tool handling for efficient machining.

My Experience with CNC Machine Maintenance

CNC machine maintenance taught me how critical regular upkeep is to ensure operational efficiency, longevity, and precision. I learned the importance of daily walkthroughs, such as checking coolant levels, ensuring proper lubrication, and cleaning the machine to prevent chip buildup. Performing a spindle warm-up and inspecting tools for wear were key daily tasks, alongside maintaining tool holders and monitoring coolant concentration with a refractometer.

Weekly maintenance involved deeper inspections, like cleaning coolant filters and checking plungers, air regulators, and auxiliary components. Monthly tasks required thorough cleaning of tool changers, carousels, and extractors, as well as ensuring proper lubrication and rust prevention. Annually, the focus was on comprehensive deep cleaning, including hidden areas like spindle covers and weight compartments.

I also learned about specific tasks like using a drumvac to drain coolant and safely dispose of it for recycling, maintaining chip augers, and ensuring proper spindle and tool functionality. Each of these processes demonstrated the detailed care needed to keep the machine running efficiently, minimize downtime, and maintain the quality of the finished parts. This hands-on experience emphasized the value of proactive and thorough maintenance.

My Experience Navigating the CNC Machine

Working on the CNC mill was an eye-opening experience that helped me build confidence in machining. I started by navigating the pendant, matching tools from the tray with the system's tool list, and performing tool changes with precision. Each tool’s specifications, such as dimensions, flutes, and sharpness, were carefully checked against the documentation to ensure they were ready for use.

Loading programs was straightforward but required attention to detail. I used the Predator application to send files to the CNC, saved them to the hard drive, and selected them under the memory menu. For manual adjustments, I utilized the jog feature, which allowed me to move the machine in fine increments, as small as .0001, for precise positioning.

Securing parts was another crucial step. I followed instructions for clamp placement, used risers when needed, and ensured proper alignment by gently tapping the part into position with a mallet before fully tightening the jaws. The cleaning process emphasized the importance of preparation, from shutting off coolant to cleaning the nozzles for the next operation.

A highlight was learning to input G-codes through the MDI (Manual Data Input) screen Behind the pendant there was a detailed chart displaying the G-codes and their functions, making it easy to reference them during operations. I used commands like G00 for rapid movement, G90 for absolute positioning, and G54 for work offsets, gaining a better understanding of how these codes guide the machine.

Overall, i had a fantastic introduction to CNC milling, blending hands-on tasks with an appreciation for the machine's precision and complexity.

Finding Offsets with the CNC Machine

I practiced two methods for finding offsets on the CNC machine: the Edge Finder Method and the Paper Method. Both techniques are essential for accurately aligning tools to parts, and they each offer unique benefits depending on the situation.

Edge Finder Method

This process began with installing the edge finder into the spindle and locking it in place using the M19 command. After setting the spindle to rotate at 500 RPM, I used the handle jog to move the edge finder toward the part's surface. Getting at eye level with the tool and part helped minimize parallax and ensured precision.

The key step was observing the "pop" of the edge finder as it contacted the material. This movement indicated alignment with the edge. To calculate the offset, we accounted for the edge finder’s radius (0.100 inches).
For instance:

On the right side, I subtracted 0.100 from my initial measurement (-10.0811), resulting in an offset of -10.1881.
On the left side, I added 0.100 to my initial measurement (-32.3887), giving an offset of -32.2887.

Paper Method

This alternative technique involved sliding a piece of paper between the tool and the part. The goal was to move the paper until slight resistance was felt, indicating the tool had made contact. Since the paper was 0.003 inches thick, we subtracted this thickness from the measurement to achieve an accurate offset.

Tool Offsets and G55 Work Offsets

I also worked on setting up tool offsets (length and diameter) in MDI (Manual Data Input) mode. Using G55, I defined the work offset for the operation, ensuring the tool started in the correct position.

Understanding Endmill Heights

A key detail was distinguishing between endmill heights:

Endmills with a Radius: The highest point is at the center of the cutter.
Endmills without a Radius: The tip of the cutter represents the highest point.

Key Takeaways

Both methods demonstrated the importance of precision in machining setup. The Edge Finder Method provided a systematic approach for alignment, while the Paper Method offered a quick and tactile solution. Combining these skills with proper tool offsets and G-code setup enhanced my understanding of CNC operations and setup accuracy.

3 Axis Challenge

Designing a Machinist Organizer

To tackle workspace clutter in machining, I designed a compact organizer for essential tools like scanners, torque wrenches, and small items. This process emphasized the value of iterative design, practical feedback, and manufacturability.

Design Evolution
The initial version featured a simple badge slot, but it lacked functionality. I iterated to include three ½-inch holes at different depths, but machining limitations led me to simplify the design. The second version enhanced the badge slot and added a small pocket for hardware, alongside a secure scanner holder. Feedback inspired a final redesign that replaced the badge slot with a torque wrench holder, refined the pocket with stepped elevations, and filleted the corners for usability.

Final Outcome
The final organizer offers functionality and efficiency, with a secure scanner holder, a designated torque wrench slot, and a versatile pocket for small items. It meets machinists' needs while reducing clutter and improving workspace organization.

Key Takeaways
This project taught me to adapt designs based on feedback, prioritize ease of manufacturing, and address specific user needs. The result is a practical tool that improves workflows and organization in a machining environment.

For more details about the 3 axis mill, go to https://sites.google.com/view/laythsportfolio/cnc-mill-3-axis

For more details about my 3 Axis Challenge, go to

https://sites.google.com/view/laythsportfolio/cnc-3-axis-challenge

Page updated

Google Sites

Report abuse