Don’t let the advertising-quality photography fool you: This is the work of an individual maker (specifically Matt of Wood&Faulk) who wants to share it with you just for the pleasure of sharing. Well, that and the traffic, probably. We all <3 the traffic. [via NOTCOT]

Back in January, John Baichtal wrote about the Bolt Depot’s downloadable PDF posters [PDF, 520K] of common (and not so common) screws, bolts, washers, nuts, and other fasteners. But we thought, in light of our Mechanics Skill Set coverage, we’d remind our readers of them. Not only is the PDF great, but the Bolt Depot web catalog offers a much deeper database of these hardware types, with nice, big illustrations of each part, descriptions, common sizing, common alloys, etc.

A big part of learning a skill set like basic mechanical engineering is knowing what parts are available, what they’re called, and how they’re used. A free resource like this goes a long way towards understanding fastening technology, all based around the gloriously simple machinery of the screw. These reference posters are great to keep in your toolbox, on your bench, or slotted into the pocket of your Maker’s Notebook.

Bolt Depot Fastener Type Chart

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All of our Mechanics coverage

We have covered the process for drilling square holes (with rounded corners) using the Watts drill before, but in the intervening time some cool videos demonstrating the process have surfaced on YouTube, e.g. the one I’ve embedded, above, from user jacquesmaurel.

The Watts drill is based on the Reuleaux triangle, and this promotional video for the book How Round is Your Circle? (which we covered back in 2009) animates the principle nicely.

Turns out it’s also possible to drill hexagonal hole using a very similar tool based on the Reuleaux pentagon. The video immediately above, again from jacquesmaurel, shows a tool he describes as a “Vika attachment,” mounted in a lathe, boring an hexagonal hole in a piece of stock. The video below, part of the Wolfram Demonstrations Project, illustrates the process.

These Reuleaux-polygon based drilling and boring processes should not be confused with the very similar process of rotary broaching. [via Core77]

We have covered the process for drilling square holes (with rounded corners) using the Watts drill before, but in the intervening time some cool videos demonstrating the process have surfaced on YouTube, e.g. the one I’ve embedded, above, from user jacquesmaurel.

The Watts drill is based on the Reuleaux triangle, and this promotional video for the book How Round is Your Circle? (which we covered back in 2009) animates the principle nicely.

Turns out it’s also possible to drill hexagonal hole using a very similar tool based on the Reuleaux pentagon. The video immediately above, again from jacquesmaurel, shows a tool he describes as a “Vika attachment,” mounted in a lathe, boring an hexagonal hole in a piece of stock. The video below, part of the Wolfram Demonstrations Project, illustrates the process.

These Reuleaux-polygon based drilling and boring processes should not be confused with the very similar process of rotary broaching. [via Core77]

When I’m taking something apart, using a magnetic parts tray for the screws and other tiny metal bits is one of the best things I can do (together with taking pictures as I go) to make sure that it all goes back together again more or less as it’s supposed to.

So the last time I was disassembling an appliance for repair (a video projector, in this case), and I was carefully arranging the screws for each subassembly in a separate little pile in my parts tray, it occurred to me that it’d be nice to have a magnetic parts tray with compartments for this purpose. And when I was imagining what the dividers would look like, a shape like the blade of a fruit wedger occurred to me.

For some reason, I have two fruit wedgers. I never use a fruit wedger, but when and if I ever decide to start, I am confidant that my needs will be served by only one.

So I busted the plastic ring off one of them and, after breaking off some small bits to round the ends of the blades, discovered that the blade assembly fit pretty well into my 4? magnetic parts tray. And actually works pretty well as a divider, too. I knocked the sharp edges off with a file.

Great looking results from the very accessible process of toner transfer galvanic etching, by Rab. [via Hacked Gadgets]

Adafruit’s most recent Part Finder Friday column featured these cool no-nonsense BUD USB 7201-C polycarbonate USB dongle cases, available at Digi-Key and Mouser and probably other places. They cost about $2 apiece if you’re only buying a couple and come in three pieces—two snap-together clamshell halves plus a connector cap—and take a 19x45mm circuit board, which seems to be a pretty common PCB size among commercial USB keys. I just ordered two to re-skin some generic thumb drives I own with bulky cases that won’t fit into the back port of my Xbox 360. Good find, guys!

The clever copy some bright marketeer wrote for SparkFun’s Heaterizer XL-3000 is turning into a pretty awesome viral advertisement for the product, and for SparkFun itself. [via Boing Boing]

Accurate layout work is the critical first step to a successful project. Without precise, repeatable marks, it is very difficult to get everything to come together at the end. So for this piece, I will go over some of the basic tools for measuring, marking, and transferring lines. My big three (actually four) tools for almost all of the work I do are the tape measure, a high quality 12″ combination square, and a .005 drafting pen. I also use a 4″ combination square for smaller work.

Measuring:
The three most common measuring devices you’re likely to find in a wood shop are the tape measure, folding rule, and steel rule. All three have their good and bad points. But as with all tools, find the one(s) that fit your style and make the most sense to you and the way you work.

The tape measure with its spring-steel blade rolled up into a small box is fast and can measure distances that would require a massive folding rule. On the down side, the little hook at the end of the tape can introduce inaccuracy. When new, the hook slides on rivets just enough to adjust for the thickness of the hooks metal. When measuring to the inside of something, the hook is pressed in; when on the outside, the hook is pulled out keeping the measurements accurate. This works great for a while, but over time, the holes and rivets can wear and get bigger, or worse. Far more common, the hook can be bent when the tape measure is dropped. To remedy this, most woodworkers “burn an inch.” This is where you ignore the hook and start all of your measurements from the one inch mark. This works well and gives accurate results, as long as you remember to subtract one inch from your result. Trust me, no one who uses this method hasn’t had a moment of dread after discovering something (or worse, multiple things) didn’t fit to the tune of one extra inch. So stay awake out there. When choosing a tape measure, consider the type of work you are doing. If you primarily work with material shorter than twelve feet, don’t buy a twenty five foot tape. Those last thirteen feet will never see daylight and the extra mass is heavy and cumbersome.

The folding rule overcomes the hook problem by having a fixed metal cap at the end of its wooden rule. This makes for worry free use, especially when measuring against something. It also has a nifty little sliding rule built into the end to measure depths and interior distances. On the downside, the thickness of the wooden blade means it must be laid on its edge to get accurate results and the way it folds creates a stair step shape that can make it awkward to use over distances.

The steel rule is a nice balance between the folders consistency and the tape measure’s small size, but its limitations are obvious. They are great for smaller work but once you get beyond the six inch mark, one of the above will have to take over.

Honorable mention goes to the story pole or story stick. This is usually a long piece of wood that one puts their own marks on for transferring measurements. This can be more reliable because it gets rid of all of those pesky numbers, and every distance is as marked. Story poles are especially useful when measuring larger projects with multiple components (like a kitchen or library) or when needing to transfer the same dimension over many parts. It helps eliminate measuring mistakes.

Squares:
For layout work, a square’s primary function is to draw lines 90º perpendicular to a side. As always, there are a few types available but what sets them apart is what else they do. For me, a combination square is the most useful. Not only does it give me 90º and the occasional 45º, it also transfers measurements from one piece to another, finds the true center of a board, and checks depths and helps set up tools. It’s hard to imagine woodworking without it. Definitely spend up when buying one. Get the best one you can afford. A loose, out of square or hard to move blade creates more frustration than it’s worth.

The speed square is handy as well but is more suited to carpentry. I find the deeply stamped numbers to make for jaggy lines so I use it mostly for rough layout and marking. The sashigane is the standard square for Japanese joinery. It looks like a western framing square but has a much thinner, flexible blade. And also like the framing square, it is covered in mysterious, oddly spaced numbers and strange markings that when in the right hands can be used to figure and lay out some pretty complicated joints. Since I have yet to decipher one, those hands are not mine.

Marking:
When it comes to making lines, thin, sharp, and readable are key. If a line is too thick or fuzzy (carpenters pencil) it’s easy to get lost as to where to cut or measure. Over the years, I’ve worked through a series of marking implements from #2 pencils (sharpen too much) to mechanical pencils (lead breaks too much) to knives (sharpening/lines can be hard to see) and even tried working with a bamboo pen for a while (never got the hang of it), but my favorite remains the .005 drafting pen. It leaves dark clear and very thin lines. I still use the others on occasion, pencil for rough layout and for places I might need to erase. Knives for when I need to cut to a super exact line. But for most situations the pen is king. Whatever you use, remember to mark a line only once. Multiple strokes not only darken it but make it wider and fuzzier and less accurate.

From the front: traditional ink line, modern ink line, chalk line

Snap Lines:
If you need to mark a straight line over a long distance, a snap line is the tool. A snap line is basically a reel of string that’s pulled through pigment and then, wait for it… snapped on a surface to make a line. The standard carpenters version has a string with a small hook that is pulled through a reservoir of (usually) blue chalk. To use it, you hook the string at one end of a board, pull the box to the other, stretch it taught and give it a snap. This leaves a reasonably good line for rough cutting. The downside is that this line tends to be wide, fuzzy, and that can be wiped or blown away, often by the tool that is trying to follow it. The Japanese ink line follows the same principal but a couple of differences. Instead of chalk, it uses ink for pigment, and it has a much thinner line with a pin instead of a hook. This allows for a very fine, dark, and accurate line that can’t be blown or brushed away. It also leaves that same ink on your fingers and everything else the string touches, so proceed with caution. Both kinds take a little practice to get the tension right and to keep the line from bouncing or snapping curved lines. They also have several different colors and permanence of chalk/ink available.

Marking Gauge:
Last up is the marking gauge. Functionally, it’s like a combination of the adjustable square and a marking knife. While the shapes and styles available are endless, they are basically a bar with a blade or a pin in the end, attached to an adjustable fence. These are especially handy when transferring the same layout lines to multiple pieces and marking lines parallel to curved edges. They are quick and, if you keep them sharp, accurate and leave clean precise lines.

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A commenter on Monday’s post about Rob Ives’ free downloadable resistor color wheel computer pointed us to the Japanese-language site of Ikkei Electronics, which provides this PDF created in 2007, and apparently dated to 1976, showing this cool hand-drawn-and-lettered version of the same idea. [Thanks, ikkei!]