Finger Joint Cutter Uses A Jigsaw Blade, But Not As We Know It

November 5, 2026 by Donald Papp 36 Comments

Around these parts, finger joints (or box joints) are usually the product of laser cutting. [bluesyann] shows us a method of using a stationary jigsaw, a custom blade, and 3D-printed jig to create a DIY box joint cutter whose results look impressive. What’s appealing is not just the end result, but the fact that the whole system is made from little more than an inexpensive tool, scrap wood, and common hardware.

A DIY wide blade cuts each notch in a single go.

In [bluesyann]’s system, the jigsaw is fixed in place to make a stationary cutter. The saw itself is nothing special; it’s the wide blade that makes the difference. It cuts a notch in a single go, and it’s made by epoxying together multiple blades to make a single extra-wide one. Jigsaw blades are not expensive, and they’re easy to snap into pieces. By using a total of three blades (snapping two of them into pieces) one can create the wide version shown here.

With a stationary jigsaw sporting an extra-wide blade that cuts the same notch every time, all that remains is a way to get the spacing right. The solution there is a 3D-printed jig that each freshly-cut notch fits onto as the next one is cut.

There are a few other details, but those are the important bits. One does have to do a bit of trial and error to get things dialed in, but once they are, it’s off to the races.

If one prefers a less hands-on method of cutting box joints, check out this robotic table saw which automates the process.

[Quinn Dunki] Makes A Screw Shortener Fit For Kings

February 16, 2025 by Elliot Williams 49 Comments

It’s common problem when you’re building anything with screws: this one is too long, this one is too short. While she can’t teach you how to fix the latter, [Quinn Dunki] has made herself an absolutely deluxe screw shortening jig. And while that’s cool and all, the real value here is the journey; watching over [Quinn]’s shoulders while she’s in the machine shop is always illuminating.

First off, she starts with her old jig, which frankly makes us want one. It’s a short piece of aluminum angle stock with threaded holes in it. You thread the screw in as far as you want, and use the edge as a cutting guide. Very nice!

But aluminum threads wear out quickly so it works if you’re shortening dozens of screws, but gets wonky when you need to cut hundreds. The new jig is made out of steel, and has a slit that clamps the threads in place so she doesn’t have to hold the tiny screws with her other hand while sawing.

This video is, on the surface, about making an improved tool out of steel. But it’s the tips along the way that make it worth your watch. For instance “deburr early and often” is a recurring leitmotif here: it keeps the extra bits that form along any cut from messing up edge finding or vise registration. And yeah, she deburrs after every operation.

There are mistakes, and lessons learned along the way. We’re not going to spoil it all. But in the end, it’s a sweet tool that we’ve never seen before.

If you haven’t read [Quinn]’s series on machine tools that she wrote for us, it’s a treasure trove of machining wisdom.

Continue reading “[Quinn Dunki] Makes A Screw Shortener Fit For Kings” →

Custom PCB Is A Poor Man’s Pick And Place

February 4, 2025 by Dan Maloney 8 Comments

Surface mount devices have gotten really small, so small that a poorly timed sneeze can send your 0603 and 0402 parts off to live with the dust motes lurking at the edge of your bench. While soldering such parts is a challenge, it’s not always size that matters. Some parts with larger footprints can be a challenge because of the pin pitch, and getting them to land just right on the PCB pads can be a real pain.

To fight this problem, [rahmanshaber] came up with this clever custom PCB fixture. The trick is to create a jig to hold the fine-pitch parts securely while still leaving room to work. In his case, the parts are a couple of SMD ribbon cable connectors and some chips in what appear to be TQFP packages. [rahmanshaber] used FreeCAD to get the outline of each part from the 3D model of his PCB, and KiCad to design the cutouts; skip to 7:30 or so in the video below if you don’t need the design lesson. The important bit is to leave enough room around the traces so that the part’s leads can rest of the PCB while still having room to access them.

Using the fixture is pretty intuitive. The fixture is aligned over the footprint of the part and fixed in place with some tape. Solder paste is applied to the pads, the part is registered into the hole, and you’re ready for soldering. [rahmanshaber] chose to use a hot plate to do the soldering, but it looks like there’s enough room for a soldering iron, if that’s your thing.

It’s a simple idea, but sometimes the simplest tools are the best. We’ve seen lots of other simple SMD tools, from assembly jigs to solder paste stencil fixtures. Continue reading “Custom PCB Is A Poor Man’s Pick And Place” →

Simple Hardware Store Hack Keeps Your PCBs Right Where You Want Them

January 16, 2025 by Dan Maloney 30 Comments

Sometimes it’s the simplest hacks that make the biggest impact.

Take these DIY magnetic PCB vises for example. Sure, you can go out and buy purpose-built tools, but [Dylan Radcliffe] just made a trip to the hardware store for some nuts and bolts. He chose 3/8″-16 bolts, which would probably be around M10 for the rest of the world. The head of each bolt is ground flat so a ceramic disc magnet can be attached to it with CA glue, while the head of the bolt gets a plastic washer glued to it. Another plastic washer gets glued to a nut, which when threaded onto the bolt provides the light clamping force needed to hold a PCB. Make four of those and stick them to a steel plate with the magnets, and you can stop chasing your boards around the bench with a soldering iron.

As much as we like this idea — and we do; we’re heading to Home Depot to buy the needed parts this very evening — we can think of a few useful modifications. With a long bolt and two nuts rather than one, you could make a set of vises that are easily adjustable along the Z-axis. This could prove useful to those of us working under a microscope. Also, rather than making the bolts the magnetic part we bet you could lay down a flexible magnetic sheet, the kind you can feed into a printer to roll your own fridge magnets. We suspect that would hold the bolts firmly enough for most work while still allowing easy repositioning. We’d also favor flange nuts over plain hex nuts, to give a larger clamping area. We’d still include the plastic washers, though, or possibly switch to rubber ones.

There’s more than one way to skin this cat, of course, especially if you’ve got a Harbor Freight nearby and a well-stocked Lego bin.

Drilling Rig Makes Accurate Holes In Seconds

November 23, 2024 by Zoe Skyforest 19 Comments

Drilling holes can be quite time consuming work, particularly if you have to drill a lot of them. Think about all the hassle of grabbing a part, fixturing it in the drill press, lining it up, double checking, and then finally making the hole. That takes some time, and that’s no good if you’ve got lots of parts to drill. There’s an easy way around that, though. Build yourself a rad jig like [izzy swan] did.

The first jig we get to see is simple. It has a wooden platter, which hosts a fixture for a plastic enclosure to slot perfectly into place. Also on the platter is a regular old power drill. The platter also has a crank handle which, when pulled, pivots the platter, runs the power drill, and forces it through the enclosure in the exact right spot. It’s makes drilling a hole in the enclosure a repeatable operation that takes just a couple of seconds. The jig gets it right every time.

The video gets better from there, though. We get to see even niftier jigs that feature multiple drills, all doing their thing in concert with just one pull of a lever. [izzy] then shows us how these jigs are built from the ground up. It’s compelling stuff.

If you’re doing any sort of DIY manufacturing in real numbers, you’ve probably had to drill a lot of holes before. Jig making skills could really help you if that’s the case. Video after the break.

Continue reading “Drilling Rig Makes Accurate Holes In Seconds” →

Custom Polyurethane Belts Made Easy

May 15, 2024 by Zoe Skyforest 13 Comments

If you need to make polyurethane belts in custom lengths, it’s not too hard. You just need to take lengths of flexible polyurethane filament, heat the ends, and join them together. In practice, it’s difficult to get it right by hand. That’s why [JBVCreative] built a 3D printed jig to make it easy.

The jig consists of two printed sliders that mount on a pair of steel rods. Each slider has a screw-down clamp on top. The clamps are used to hold down each end of the polyurethane filament to be joined. Once installed in the jig, the ends of the filament can be heated with a soldering iron or other element. and then gently pushed together. The steel rods simply enable the filament to be constrained linearly so the ends don’t shift during the joining process.

The jig doesn’t produce perfect belts. There’s still a small seam at the join that is larger than the filament’s base diameter. A second jig for trimming the belt to size could be helpful in this regard. Still, it’s a super useful technique for making custom belts. This could be super useful to anyone needing to restore old cassette decks or similar mechanical hardware.

Continue reading “Custom Polyurethane Belts Made Easy” →

Modular Vacuum Table Custom-Fits The Parts

March 31, 2024 by Donald Papp 3 Comments

[enhydra] needed to modify a bunch of side inserts from some cheap ABS enclosures, and to save time and effort, he created a simple vacuum table with swappable inserts to precisely fit the parts. Suction is provided by a shop vacuum (plugged in near the bottom in the photo above) and it worked very well! Sealing and gaskets weren’t even required.

A vacuum table provides a way to hold workpieces flat and secure while a CNC machine does its thing, and because no clamps are involved, it can really speed up repetitive work. [enhydra]’s solution combines a vacuum table with a jig that ensures every rectangular piece is held exactly where the machine expects it to be, making the whole process of modifying multiple units significantly more efficient.

The whole thing — vacuum table and modular top — was straightforward to CNC cut out of what looks like particle board and worked as-is, no added gaskets or seals required, making this a very economical solution.

Vacuum tables can be pretty versatile and applied in more than one way, so keep that in mind the next time you’re wondering how best to approach a workshop problem. We’ve seen a well-engineered table used to speed up PCB milling, and we’ve also seen a DIY vacuum table combined with a heat gun and plastic plates from the dollar store make a bare-bones thermoforming rig.