Aluminum, as we know, is a lightweight metal that can be easily curved and worked, and it is found in numerous fields because of its ability to resist corrosion. However, to make aluminum work, one needs to employ certain techniques, particularly when drilling and tapping. If you would like to learn the steps on how to drill and tap aluminum correctly, as well as other important guidelines on which drill bits and taps are suitable when working with aluminum, read the rest of this article.
Understanding Aluminum’s Properties
Before presenting the process of drilling and tapping aluminum, it is useful to give some insights into the material’s properties. It costs less than steel, is softer and easier to machine, but tends to gall and seize as it is being machined. It also produces heat very fast, which in turn poses some challenges in terms of the tools used. This information proves useful when it comes to the right choice of tools and techniques to use in order to effectively drill and tap aluminum.
How to Drill and Tap Aluminum?
Step 1: Selecting the Right Tools
Deciding on the right tools to use is very important in the drilling and tapping of aluminum. The right tools also make the work easier and give a clean and a precise outcome.
- Drill Bits: Always employ high-speed steel (HSS) or cobalt drill bits any time you drill and tap aluminium. These materials cope with heat produced when drilling the aluminum. A 135-degree split point, or 118-degree helical points, are advisable to decrease the walking and be as accurate as possible. Also look for drill bits with larger flutes and faster spirals. Both will help to quickly evacuate the aluminum and help prevent flute packing.
- Taps: When it comes to tapping aluminum the recommendation is to use high-speed steel taps. The optional taps for aluminum are forming taps. Aluminum is ideal for forming and using forming taps will result in long tool life and low cost per hole. If a cut tap is required, choose one with plenty of flute space for chip evacuation.
Step 2: Preparing the Aluminum Surface
Before you drill and tap aluminum, do this and that to the surface. Before the process, clean aluminum to reduce any outer layer that may potentially interrupt the formation of the oxide layer. It maintains the position of the drill by placing a center punch at the location where it is going to be drilled.
Step 3: Drilling the Hole
With the surface prepared and tools ready, start the drilling process:
- Drilling Speed: Avoid going very fast when drilling through aluminum so that you do not apply excessive pressure that may cause the hole to overheat. Do not perform the driving at excessively high speeds, as this leads to high temperatures resulting from high speeds. It is preferable to have a speed of between 2000 and 3000 RPM.
- Lubrication: Aluminum should always be lubricated because it is inclined to stick to the drill bit and because a lot of heat is generated. It is best used with cutting oil, WD-40, or kerosene. It is recommendable to use excessive amounts of lubricant on the drill bit and on the aluminum surface.
- Drilling Process: Start drilling gently, giving equal pressure without stabbing the bit. After the hole has been drilled, it is proper to use the deburring tool to wipe out any burrs or razor-like edges.
Step 4: Tapping the Hole
After drilling, the next step is tapping the hole:
- Lubrication: Aluminum must be lubricated when it is tapped. Before performing the operation, coat the tap and the hole with the lubricant.
- Tapping Process: When using forming taps, the taps can be run at recommended speeds. For extra productivity, you can also try faster speeds. When using a cut tap,carefully review the recommended speeds. In CNC equipment the tap can progress straight thru the part. For hand tapping it is suggested that the tap should be reversed a little for every couple of turns to break the chips and to clear the threads. The combination of both linear and circular movement is crucial in order to avoid the phenomenon known as the ‘binding’ of the tap.
- Completion: Continue until one has drilled to the right depth of the tap. Afterwards, it is necessary to turn the tap and to take out all the remaining chips from the hole.
Step 5: Finishing Up
After you drill and tap aluminum, you need to make sure that the threads and the hole are clear from any debris and have a proper finish. The remaining metal shavings should be blown away using compressed air or maybe brushed off. If required, then to measure the correct thread, one can always use the thread gauge. As for several exposed threads, use the thread sealant or anti-corrosion treatment for the threads to ensure that they do not get harmed.
Conclusion
Learning how to drill and tap aluminum is a viable skill to learn in the modern workplace in a range of fields. It’s therefore important that one employs the right tools, makes sure they are adequately lubricated, and that their working speed is regulated. With these practices, you can confidently tackle any aluminum project.
