Machining industrial parts require a considerable degree of precision. That’s especially true with computer numerical control (CNC) machining, where grinders, lathes, and turning mills make a predetermined set of cuts to a given material. The part being worked on must be held firmly in one position to ensure the cutting tool doesn’t miss a step. If the part shifts position during machining, the resulting product will be defective and may be non-functional, forcing you to start the process all over again.
That’s the whole essence of workholding solutions. This article covers everything you need to know about workholding solutions.
The Role Of Workholding Solutions
The primary role of workholding solutions is to keep the part being machined immobile and stable. They are crucial because gross errors may arise if the item shifts from its position. For instance, if it’s threading a bolt, the threads may misalign, making it impossible for a nut to be used with the bolt.
Another thing to note is that the machining process typically exerts some force on the part. If it is not held firmly in position, it may be impossible for the CNC machining to be completed. If the workpiece moves even a few millimeters, the cutting tool may not reach it.
Lastly, without a robust workholding device, fragments of the workpiece may fly off and injure the operator. The cutting tool may also dislodge and potentially harm the operator. For these reasons, the importance of a sturdy workholding solution can never be overemphasized.
Examples Of Workholding Devices
Dozens of workholding solutions exist. Below is a brief description of some common ones:
- Cam lever: This is also called a cam clamp. It’s an apparatus that enables you to adjust the clamp many times without using tools like wrenches. When you pull up the cam’s lever, you disengage the grip on the threaded serration. Pressing it down engages the device, firmly holding the workpiece. You may want to check out further resources to know how cam levers work.
- Milling/Machinist vise: It comprises a fixed and moveable jaw positioned parallel to each other, ideal for firmly gripping workpieces.
- Clamp: A clamp typically has two opposing handles, which you squeeze together on either side of a workpiece, securing it firmly in position.
- T-slots: These are T-shaped tracks commonly found on workbenches.
- Parallel bars: These are usually used with vices to elevate a workpiece that needs side-milling.
- V-Blocks: They’re perfect for cylindrical workpieces.
- Angle plates: These are used where machined objects must stay perpendicular to the machine bed.
This list isn’t exhaustive. Other workholding solutions include jaw plates, fixture plates, dividing heads, circular tables, magnetic chunks, and drilling jigs.
How To Choose A Workholding Solution
Numerous workholding solutions exist in the market. You can’t just use any you come across. Below are essential factors to consider when choosing a workholding device.
- Material type: Harder materials generally require sturdier workholding solutions because the cutting tools exert considerable force. Using an extremely hard workholding device on soft workpieces, like plastic or aluminum, may lead to deformation.
- Material shape and size: As mentioned earlier, a cylindrical workpiece may require a v-block to stay in place. The standard vise with parallel jaws may not work. On the same note, machining an enormous workpiece with an irregular shape may require sophisticated clamping.
- Work volume: If you use the workholding device repeatedly to machine hundreds of parts, selecting one that requires little maintenance and can maintain a high degree of accuracy even with continuous use is prudent.
- Versatility: An excellent workholding solution allows for multiple machining operations on different faces of the workpiece.
- Speed of operations: For optimum efficiency, you’d want a workholding apparatus that’s easy to load and unload.
- Safety: The operator should use the workholding device without undue risk of injuries or a likelihood of clamping the object being machined incorrectly.
- Affordability: In some sense, a workholding device doesn’t directly increase the number of parts you manufacture over a given period. It’s part of manufacturing costs, which must be kept at a minimum for your manufacturing business to remain profitable. So, choose one that doesn’t eat too much into your budget. However, don’t compromise on quality.
As you can see, choosing an appropriate workholding solution is an intricate process you can’t afford to skimp on.
Conclusion
Workholding devices are a must-have when machining parts. They help hold the workpiece in a fixed position for accuracy and safety. As there are numerous types you can choose from, you’d want to learn the typical factors for consideration, as outlined herein. For an even more perfect choice, consult professional manufacturers on the best devices to use.
Ultimately, you’ll manufacture premium quality parts at a faster rate.