All,
August was a full house: sixteen of us, THREE of them named Steve (a new record, I think), plus a guest appearance by James’s mini-me Luke. Michael ran the Laser SIG a few minutes long and then bought forgiveness with those dangerous cookies, which worked immediately! And the show-and-tell delivered: a wooden computer, a dinosaur plan, and two pool cues that had us thinking about nothing but the 8 ball.
The intros alone were worth the price of admission. Shane opened with “I’m two weeks sober off the CNC.” We then staged an intervention on the spot: get back on the machine, Shane–it’s the healthiest addiction out there! Frank told us about the secret message he was going to inlay INSIDE a glue joint, where nobody would ever see it, until VCarve’s inlay builder refused to do a zero surface gap and the message went to the grave unwritten, or did it?! Robbie has been generating gear trains for axles that need to spin at exact ratios, which may end up as a donor recognition wall of moving gears for the space. And James made a cutting board so nice the recipients cried and swore they would never cut on it, which he considers a design flaw. “I should have thrown it in the dirt a little or something.”
Martin raised the bar for first CNC projects, possibly permanently. His first ever cut: a working three-bit binary adder in African mahogany, run entirely by marbles, inspired by the 1960s Digicomp2. Marbles in one side count up, carries and all; marbles in the other side sweep the bits back to zero through little L-shaped gates. It’s a two-sided carve, and the lessons came fast. Attempt one died when a long bit sat too far out of the collet and wobbled the material to bits. Attempt two went halfway from each face with screw-hole registration and landed inside his one-millimeter tolerance. The tiny gates cut without enough tabs flew off the machine, and he learned that a tab on the grain-weak side barely counts as a tab. Total mahogany bill for the two parts he showed: about $7. His verdict on the mechanism: “way more consistent than I could’ve hoped.”
Steve’s craft-fair furniture line keeps growing: this month a modern slatted bench, curved pieces CNC-cut from about a third of a sheet of plywood and aligned with dowels through the three-quarter-inch layers. He tested it the scientific way, by sitting on it. It held. The glue-up fought back though: the dowel-heavy assembly started setting before everything was clamped, left a slight bow, and since the legs are glued straight into the top there is no putting it back on the machine to flatten. That kicked off a good long conversation about tabs versus onion skin, down-spiral bits packing the kerf, and whether shipping-friendly knockdown legs are the move for fairs. Steve’s position on tabs is a matter of public record: “I hate tabs. I hate the post process.”
Remember Zach’s zig-saw.com from last month? He asked for beta testers, and Brian actually did it. He fed it a leaf image, let the site split it into layers, and cut the default roughly 10x10 design in three-quarter stock with a quarter-inch and an eighth-inch end mill, straight from zig-saw’s G-code, no VCarve anywhere in the chain. Verdict: “The program worked fine.” He did have to multiply the generated speeds by ten to get a reasonable feed rate, and the sample shows faint shadow cuts between layers, possibly from Z-zero drifting between tool changes. Which is to say: it’s early software, it works, and it needs exactly this kind of feedback. That is why we have these meetings!
Austin went deep on Fusion 360 as his CAM program and brought a kitchen spoon rest to show for it. The adaptive-clearing ramp came out so smooth the steps are barely there under your finger. The drama came from elsewhere: the collet clipped the tall geometry while tracing the perimeter and took the retaining tabs clean off. The lesson, hard-earned: Fusion can only warn you about that collision if your tool definition includes the holder and the actual stickout, so model the whole stack, collet and all.
Shanda is planning something wonderful: a Tyrannosaurus rex skeleton, scaled up from an Etsy design meant for three-millimeter stock, cut instead from one-inch insulation foam and standing around seven feet tall. Maybe ten. Maybe glow-in-the-dark, as a front-yard voter-registration attraction. The room piled on with foam wisdom: use an up-cut O-flute, and once the cut runs deeper than the flutes can clear, trapped foam melts around the bit and gouges the part, so widen tight profiles into half-inch pockets and let the chips out. Add dogbone corners, cut slot-clearance tests instead of trusting a nominal one-inch fit, and reinforce the long floppy bones. Her words: “I would love to make this glow in the dark.” Same.
Towards the end of the meeting Pete passed his finished pool cues around the room, with the reasonable request: “Please don’t drop them.” These were turned on the lathe rather than the CNC, but nobody held it against him =). Handmade rings, a decal set under the finish, wood and epoxy bodies cast in capped inch-and-a-half PVC pipe. One cue has already sold. The finish process is its own show: he pours Quick Coat epoxy along the cue, spreads it with a playing card, and lets it self-level while the lathe turns at about 130 RPM for two to three hours. His remaining nemesis is voids in the castings, which survive even a pressure chamber, so the room dug into the physics: pressure shrinks bubbles, vacuum removes them, and staged pours shorten the distance trapped air has to travel. Watch this space.
A couple of other useful notes from the meeting:
The 1/4" MDF sheets racked next to the 5x10 are there for personal overlay spoil boards, about $15 each, meaning that you can grab them since it’s cheap for Asmbly to purchase, or at least much cheaper than the 3/4" sheets. Drop one on the main board, surface it flat, and the vacuum still holds your work right through it. Use it any time a jig, a tight dado, or shallow engraving needs a true reference, and reuse it until it’s about an 1/8" thick. Also, as an FYI, the surfacing cutter lives in the back of the big white computer cabinet, for anyone who has circled the shop looking for it.
As is typical in our meetings, Brian, the resident architect of chaos and mayhem, made a standing offer that deserves a spotlight: if you’ve taken the class and are nervous about your first real cut, Brian will stand next to you while YOU run the machine, like he did for Martin. Brian’s recovery tip from the same conversation: switch the controller to absolute machine coordinates and write down your work origin, because one stray XY-zero press during a bit change can erase it.
We also have the August CNC SIG recording here for anyone who wants to revisit the discussion or catch what they missed:
Next CNC SIG: Sunday, September 6, 2026, 12:30 PM. Come early for the Laser SIG at 11:00 AM (CO2 lasers, Michael’s crew) and make it a double-header. Bring a project, bring a failure, bring yourself!
Cya guys then!
@jamesfreeman @SteveW @sneezix @bwatt @cjromb @atwatsoniii @rjnevels @pconklin2000 @andrewl @michleon100
