Shelly | Global Nest Machining

Founder, Global Nest Machining. CNC parts for robotics & semi hardware teams. ±0.01 mm on critical features · 1-pc MOQ · 24h quotes. DFM tips daily ↓

[Shelly | Global Nest Machining @Shelly38499228]

I'm Shelly, founder of Global Nest Machining.

We machine precision CNC parts for robotics and semiconductor hardware teams:
• ±0.01 mm on critical features
• MOQ of 1 — prototypes welcome
• Quotes in 24h, lead time 1–2 weeks
• ISO 9001, US sales office in Chino, CA

I post practical DFM tips here so your drawings get cheaper and faster to make.

Follow along. Have a part? Send a STEP file + tolerances: [email protected]

[Shelly | Global Nest Machining @Shelly38499228]

@XRoboHub 38 DoF means dozens of tiny curved joint surfaces that all have to wear the same way. The braided ligament idea is clever. How do they keep those joint surfaces consistent from one hand to the next in production?

[Shelly | Global Nest Machining @Shelly38499228]

@IlirAliu_ This makes sense from the shop side. Blind peg insertion only works if the parts are consistent: same chamfer, same bore size, every time. Good encoders still need repeatable parts to work with.

[Shelly | Global Nest Machining @Shelly38499228]

@CyberRobooo Ladder climbing is as much a hand and wrist test as a balance test. Full body weight goes through small finger joints and wrist mounts on every rung. Would love to see how those parts look after a few hundred climbs.

[Shelly | Global Nest Machining @Shelly38499228]

@MakinoMachine Reaming the same pin hole from 3,000 to 30,000 RPM is a great way to show spindle quality. Hole size and finish at the high end is where a lot of machines start to drift.

[Shelly | Global Nest Machining @Shelly38499228]

@SemiAnalysis_ @JordanNanos Particles are the whole game in hybrid bonding. One speck between two wafers and that area won't bond. How much of the track design is really about keeping surfaces clean from the last clean step to contact?

[Shelly | Global Nest Machining @Shelly38499228]

Deep, narrow pockets quietly drive up CNC cost.

A tight corner radius forces a small end mill, and small tools can't cut deep without chatter or breakage. My rule of thumb: pocket depth under ~4x the tool diameter.

Need it deeper? Open up the corner radius.

[Shelly | Global Nest Machining @Shelly38499228]

@Vectarrr Agreed. On most drawings I see, only a handful of features truly need a tight callout. Everything else can sit under the general tolerance block, and nobody downstream notices except the price.

[Shelly | Global Nest Machining @Shelly38499228]

Tolerances are the quietest cost driver on a CNC drawing.

DFM series, part 1: where to hold tight tolerances, where to relax them, and why it changes your quote. 🧵

[Shelly | Global Nest Machining @Shelly38499228]

@agilityrobotics Thanks Jonathan and team, really useful answer. Moving parts to sheet metal and casting is what makes a robot buildable at volume. The machined parts that stay tend to be the precision interfaces: bearing seats, joint housings, mounting faces.

[Shelly | Global Nest Machining @Shelly38499228]

@IlirAliu_ Love that the prop is 3D printed. Printing is the fastest way to test a shape like this. Once a part has to survive 300 thrust changes a second, that's when I'd want the hub and motor mount machined.

[Shelly | Global Nest Machining @Shelly38499228]

@agilityrobotics @nvidia Standardizing compute is a quiet win for the mechanical side too. One module size, one mounting pattern, one thermal path means the brackets and heat-spreading parts around it can stay the same across builds. That's what makes a robot easier to build and service.

[Shelly | Global Nest Machining @Shelly38499228]

7/ My rule: pick the cheapest material that meets the real requirement, list acceptable alternates on the drawing, and ask your shop what's in stock.

Part 3 next Thursday: surface finish callouts. Follow so you don't miss it.

[Shelly | Global Nest Machining @Shelly38499228]

1/ DFM Part 2: material choice moves your CNC price and lead time more than most drawings suggest. Here's how I think about it when a new part lands on my desk.

[Shelly | Global Nest Machining @Shelly38499228]

6/ Stock size matters too. If your part is 50.5 mm thick and standard plate is 50 mm, the shop has to buy the next size up and cut most of it away. Check standard bar and plate sizes before you lock dimensions.

[Shelly | Global Nest Machining @Shelly38499228]

@CyberRobooo Early production on a high-volume line is where design freezes start to matter. Every late change to an actuator housing or bearing seat ripples into fixtures, inspection and spare parts. Teams that lock mechanical interfaces early ramp fastest.

[Shelly | Global Nest Machining @Shelly38499228]

@SawyerMerritt @Tesla A facility that size pulls a whole supplier base with it: fixtures, tooling, machined brackets and replacement parts. The plant is the headline, but the local supply chain that grows around it is what keeps the lines running.

[Shelly | Global Nest Machining @Shelly38499228]

@agilityrobotics Question for Jonathan: as Digit moves toward broader deployment, which mechanical parts changed the most between versions, and which did you deliberately freeze to make production and service easier?