Drill bits are so cheap that when one is too chowdered up to keep working, we generally just toss it out. So you might expect a video on sharpening drill bits to be somewhat irrelevant, but [This Old Tony] makes it work.
The reason this video is worth watching is not just that you get to learn how to sharpen your bits, although that’s an essential metalworker’s skill. Where [This Old Tony]’s video shines is by explaining why a drill bit is shaped the way it is, which he does by fabricating a rudimentary twist drill bit from scratch. Seeing how the flutes and the web are formed and how all the different angles interact to cut material and transport the swarf away is fascinating. And as a bonus, knowing what the angles do allows you to customize a grind for a special job.
[This Old Tony] may be just a guy messing around in his shop, but he’s got a wealth of machine shop knowledge and we always look forward to seeing what he’s working on, whether it’s a homemade fly cutter or a full-blown CNC machine.
Continue reading “Sharpening Drills Bits the Hard Way”
Wood may seem like a soft, weak material if you’re used to working with steel, but to do good work, you’ll quickly learn you need your tools sharp. Buying and maintaining a good set of tools can be expensive for the home gamer, so [shopbuilt] put together an Instructable on how to sharpen your woodworking tools on a budget.
The trick is to use sandpaper. It’s a good quality abrasive material and is readily available. You’ll want a selection of different grits – low grits to get started, higher grits when finishing. The reason this is cheaper is that you can get a selection of 5-10 different sandpapers for under $20. Getting even a couple of decent sharpening stones wouldn’t be possible at that price. In the long run, they’ll last longer but this is a budget option we’re talking about.
Obviously you can’t just sharpen something with sandpaper – [shopbuilt] suggests mounting the paper to the flattest surface you can find. The use of a tempered glass panel from a fridge shelf is, in our mind, an inspired choice here. 3D printer enthusiasts have been using similar techniques for heated beds for the best part of a decade now.
We love woodworking here at Hackaday, so get your feet wet with these woodworking basics for the hardware hacker.
When sharpening a knife, it is critical to have the knife at the right angle. A knife jig handles this for you, letting you focus on getting the edge right. You could just buy one, but where’s the fun in that? [origamimavin] decided to make his own adjustable knife jig using bits he bought from the hardware store for $27, and which you might have in your junk pile. Fortunately for us, he’s written up the process in excellent detail, explaining the how and why of each step.
He used a couple of tools that you might not have lying around (a bandsaw and a belt sander), but these could be easily replaced with their manual cousins, or your local hackerspace will doubtless provide you access to them. Either way, it’s a simple build which could help your knives keep their clean, sharp edge for years to come.
Poor [makendo] had seven broken bread makers lying around, all with failed paddle drivers. Since they also all have big motors and other useful parts in them, he decided to turn one of them into a powered tool-sharpening turntable.
First, [makendo] salvaged the motor, the gear, and the thick circular glass window from one of the bread makers. He cut a platter from plywood the size of the glass window, chamfering the edge to fit the gear. Next, he built a housing from scrap plywood, separating the motor from the platter with a crosspiece to keep the motor free from dust. A large magnet on a hinge collects metal powder from the system quite effectively. The sharpener spins at about 200RPM: fast enough to do the job and slow enough not to get hot.
According to [makendo], the sharpener restores bevels nicely but doesn’t make edges”scary sharp”. To that end, he used a toaster oven door as a base for a series of micro-abrasive grits of sandpaper as a finishing rig. In order to sharpen his chisels uniformly, he made a jig to hold them firmly in place against either the powered turntable or the fine sandpapers.
[Thanks for the tip, Scott]