The functioning and quality of machined components depend heavily on finishing procedures. The holes in your workpiece will have the highest diameter accuracy, dimensional tolerance, and higher surface polish thanks to reaming, one of the finishing procedures. Manufacturers often employ it following the completion of drilling operations.
Reaming: what is it? What are its objectives? How can the reaming process be optimized? This page provides answers to these queries by going into great detail on the CNC reaming procedure, including any issues that may arise and advice on how to get the best outcome.
Reaming: What is it?
Reaming is a cutting technique used to improve the surface quality of the hole’s walls and more precisely enlarge existing hole sizes. “Reamer” is the name of the reaming tool used for the reaming procedure. Compared to boring or drilling, this method is a finishing operation and does not cut a lot of material. Furthermore, when cutting the workpiece, the hole reamer rotates at exactly half the RPM of the drilling process.
What Does Reaming Serve as?
Reaming holes in a workpiece is primarily done to increase its tolerance level, surface quality, and dimensional accuracy. Because of its speed and affordability, reamer machining is the preferred choice for manufacturers. With its precision grinding capabilities, CNC reaming can produce holes with precise diameters and sizes, improving surface smoothness.
Since the hole must be prepared before reaming, procedures like drilling and boring come before reaming metal. When you need to maintain tolerances of -/+ 0.002″ or more on the hole diameter, a hole reamer is a great option to think about.
A Comprehensive Guide on Reaming a Hole
You must prepare your holes with the appropriate quantity of stock for the reamer to cut in order to achieve the greatest results from this precise machining. If the stock is too tiny, the reamer scratches the hole, leaving the diameter less than needed. On the other hand, an excessive amount of stock might cause the hole to enlarge and have a rough surface.
To ream a hole, follow these steps:
Step 1: To prevent the workpiece from sliding or rocking, make sure it is stationary and secure it with clamps. Use the appropriate reamer size to ream the hole. The reamer is usually 1.5 times bigger than the hole.
Step 2: Use a spot drill with a slightly greater taper than the drill used to create the original hole to locate and spot-drill the hole in the workpiece. To attain the desired results, don’t use a center drill, though.
Step 3: To find the ideal drill size, it’s a good idea to subtract 2% to 4% from the reamer’s size. This is 4% for softer materials and 2% for stronger metals.
Step 4: Use the feed and speed that are appropriate for the operation, material, and reaming tool. However, during CNC reaming operations, make sure the drill and hole are properly lubricated with coolant or cutting oil.
Step 5: Regulate the reamer’s feed and speed
Use between half and two-thirds of the hole-drilling speed for rotation per movement (RPM);
Feed: Make use of double the drill’s feed.
Step 6: To break the edge, file the top of the hole with an 82º or 90º countersink.
Step 7: Since reaming procedures do not always require heavy cutting fluids for optimal performance, use lighter cutting oil or coolant for lubrication. It enables you to precisely measure and smooth the walls of the hole.
Step 8: Don’t stop the reamer in the middle of its work or use it to peck the walls of the hole until it emerges through the bottom. When the machine is off and the spindle is not operating, pull the reamer directly out of the drilled hole.
In conclusion
For cutting holes in your workpiece, reaming is one of the typical finishing methods. It is a cost-effective and useful processing technique for tiny holes. However, it would be beneficial to focus more on utilizing the correct reamers with the suitable helix angle in order to achieve the optimum outcome from your reaming operations.
FAQs
What uses does the reaming process have?
In addition to providing a high-quality finish with exact dimensions, the reaming procedure is frequently used to eliminate burrs and simple hole expansion.
Why is the reamer chattering?
The machine or bushing’s lack of stiffness causes the reamer to rattle. Additionally, it happens as a result of too-light feeds, shaky workpiece gripping, or excessive reamer overhang.
What benefits does reaming offer?
The benefits of reaming include increased feed rate and better bore accuracy. Similarly, high-speed reaming contributes to improved bore finishing, which improves the hole’s surface quality.