DP254B - 7-7/8” Chamfered Edge Drawer Pull - chamfered edge
End mill speeds and feeds calculatormetric
To start the hole you will need a pilot hole. A bit around 3 or 4mm is ideal for a pilot hole. Once the pilot hole is drilled, then change up to a larger bit. If you require a hole of around 12mm, its sometimes easier to use an intermediate size, like an 8mm, especially if you power drill isn’t particularly powerful. It is essential to keep the bit as sharp as possible or there is a chance it will wander or overheat. Overheating a drill bit will damage it beyond repair.
If you are drilling a deep hole of into think material you will need to remove the bit from the hole occasionally to allow any swarf to be removed from the hole.
End MillRPMcalculator
It is essential not to run a drill too fast on stainless steel as it will heat up easily and become hard, making it very difficult to drill.
Lubrication may well be required especially if you are drilling something thicker than the diameter of the bit, and always on stainless steel. Speed is another key factor for drilling metal. Take a look at the chart below for a guide.If your power drill does not have a variable speed control a good way is to intermittently pull the trigger on and off. This will give it a chance to slow and reach an optimum speed.
Use these as a basic guideline for twist drills. Your power drills handbook should have the settings for speeds listed assuming it is variable speed.
End mill speeds and feeds calculatorapp
The Free Speed and Feed Calculator is a small simple to use Windows program that assists calculating spindle speed and feedrate for engraving tools, end mills, and drills. The free program also performs calculations to display line width of conical engraving tools with different angles and tip widths at different depths. It does not require an internet connection to use the program and no other items such as usage or tracking cookies are installed with the program.
Once you have marked where you need the hole you will need to centre punch it. This will provide a start for the drill bit, preventing it from slipping or skating and ensuring accuracy. Line up the point of the tool with your mark, then hit the punch with a hammer to create a small round indentation. Be careful doing this on thin metal, you may need something behind to prevent it denting a larger area. When drilling metal you should always wear safety goggles. Be aware that the drill could jam in the hole as it breaks through the underside of a larger hole. Keep a good grip on it at all times. Also be aware of any sharp edges or burrs that the holes may have. Burrs can easily be removed using a file.
As your drill bit breaks through the underside ease up on the pressure to help prevent it grabbing.Buy the best cutting tools you can justify. Even if you purchase a full set of low priced unbranded ones, also get yourself a few sizes of good quality bits, a 3mm, 4mm, 5mm, 6mm will come in handy.