Most seasoned DIY types prefer to use high speed steel bits it seems. That’s because these tools are great for drilling into most wood and metal surfaces. You need to understand the principles of drilling, while maintaining respect for the object you are drilling into. In this article, Alf – he’s a regular London general builder on Mr-Skill – is going to tell us how we should drill into mild steel.
Alf says, “First, select a high speed bit smaller than the diameter of the finished hole required. The drill itself is important too, because a semi-professional, variable speed impact power tool will make the job so much easier. It should also have a reverse switch for easing the bit out nicely once you’ve drilled your hole. Once you have your pilot hole, load up the correct diameter bit to finish the job.”
If drilling is really not your scene, rather get a general building quote from one of our members here on Mr-Skill. As a guideline, first use a bit that’s approximately half the diameter of the eventual hole size. In other words, if your final hole measures 8mm (5/16-inch), drill the pilot hole with a 4mm (5/32-inch) bit.
Use a centre punch and hammer to mark the hole you are about to drill – a swift gentle tap should do it, and this will act as a guide for the bit once you start drilling. If you don’t, the chances are good that your bit will wander all over the surface. Many of our customers prefer to find a general builder on Mr-Skill.
Apart from tensile strength, steel has a uniform texture too. This is to avoid any unevenness in the sheet, which in turn allows for a simpler drilling action. It is important to properly secure the steel surface before drilling, because if you don’t, you risk having the object replicating the drilling motion and spinning dangerously out of control.
Alf’s Final Tip
When you’re drilling into particularly hard or resistant surfaces, use short bursts of speed-to-slow motions, and keep your drill straight at all times. This way, your drill will last longer and your drilling action will be correct. Sustained high speed drilling will wear out the bit, as well as the power tool and the driller! “Go with the flow, but exercise patience at all times” is Alf’s motto!