Approved Machining

10/15/2026

“Bear hug” is not an official machined fit.

It is, however, a pretty good description of an interference fit.

Clearance fits give parts room to move. Transition fits create a snug, precise connection. Interference fits lock components together.

The right choice depends on what the assembly needs to do, not how tight you can make it.

Here's how to choose the right fit: https://www.approvedmachining.com/blog/clearance-vs-interference-fits-in-cnc-machining

10/14/2026

Same 0.060" wall.

One in 6061 aluminum. One in nylon.

They may look identical in CAD, but they won’t behave the same way under the cutter.

A short, supported 0.060" wall may be workable in aluminum. In nylon, that same thickness falls into a high-risk range for flexing, heat buildup, and warping.

Wall thickness has to follow the material.

See our starting points by material: https://www.approvedmachining.com/blog/thin-wall-thickness-limits-for-cnc-machined-parts

Learn how material, geometry, and tolerances affect CNC machining wall thickness, with practical limits, cost tradeoffs, and design strategies.

10/13/2026

BEARING BORE: I control alignment.

SEALING SURFACE: I prevent leaks.

COSMETIC FACE: Everyone sees me.

MACHINIST: Great. But which one of you is most critical?

DRAWING: …

A machinist can manufacture what the drawing defines, but can’t read the designer’s mind.

If a feature controls fit, alignment, sealing, movement, or appearance, the drawing needs to say so. Tight tolerances alone don’t tell the whole story.

Here’s how: https://www.approvedmachining.com/blog/how-to-communicati-critical-to-function-features-on-machined-part-drawings

10/08/2026

QUICK: What are we looking at?

A) A metal maze
B) A very small road map
C) A fluidics plate
D) A machinist’s concentration test

The answer is C. Possibly D.

This fluidics plate features branching channels, shaped pockets, holes across the face and edge, and a broad machined surface surrounding them. There's a lot of geometry packed into one plate, and every feature has to land exactly where the drawing says it belongs.

What complex geometry can we machine for you?

Request a quote: https://www.approvedmachining.com/request-for-quote

10/07/2026

PART A: I’m within tolerance.

PART B: So am I.

ASSEMBLY TEAM: Then why won’t you two fit together?

It sounds like a case for couples counseling, but it’s actually a common assembly problem.

Each machined component can meet every requirement on its own drawing and still bind, wobble, leak, or refuse to assemble. The problem often lies in the relationships between the parts: incompatible datum structures, accumulated tolerance variation, finishing buildup, or missing assembly context.

Before blaming either part, take a closer look at the system.

Our latest blog covers six ways to help multiple machined parts fit together the first time: https://www.approvedmachining.com/blog/6-ways-to-ensure-multiple-custom-cnc-machined-parts-fit-together-the-first-time



Related: SME

Learn why individually compliant machined parts may not fit together and how better datums, tolerances, documentation, and verification reduce risk.

10/06/2026

"Long and stringy" is an excellent review for noodles.
..it's a terrible review for aluminum chips.

Aluminum 5052’s softness and ductility make it great for bending and welding. But during machining, those same qualities can produce stringy chips that don’t break cleanly.

Aluminum 6061 is better behaved. It produces cleaner chips, holds tight tolerances more easily, and delivers better surface finishes.

For National Noodle Day, enjoy your noodles in a bowl. Keep them out of the CNC machine.

Learn why 6061 is usually the better aluminum for machined parts: https://www.approvedmachining.com/blog/aluminum-5052-vs-6061-for-cnc-machining



Related: The Aluminum Association

10/01/2026

★★★★★ Monday: Perfect dark roast.

★★★ Tuesday: A little weak.

★ Wednesday: Who put vanilla in this?

Coffee drinkers notice when the same order produces three different results. CNC machining customers do, too.

Consistency builds trust. That’s why repeatable machining processes, first-piece inspections, and final inspections are essential to delivering quick-turn parts without compromising quality.

For International Coffee Day, we’ll raise a cup to predictable results. Preferably a cup containing exactly what we ordered.

See how Approved Machining builds quality control into every project: https://www.approvedmachining.com/blog/quick-turn-cnc-machining-services



Related: ASQ

09/30/2026

It’s the last day of September, and New England golf season may only have another month left. If you’ve been meaning to get out there, consider this your reminder.

While golf is on our minds, here’s a design lesson worth borrowing from the course.

Nobody plays every shot with the same club.

Similarly, your drawing probably doesn’t need the same finish callout on every surface.

Sealing surfaces, bearing interfaces, and sliding components may need a finer finish because roughness affects how they perform. A nonfunctional pocket can usually stay closer to a standard as-machined finish.

The difference shows up on the quote. Smoother surfaces can require slower feeds, additional tool passes, and more machining time, so specifying a fine finish everywhere may mean paying for smoothness the part doesn’t need.

Like club selection, the right finish depends on the job in front of it. And unlike a golf score, lower isn’t always better.

Learn more: https://www.approvedmachining.com/blog/how-to-choose-the-right-surface-finish-for-cnc-machined-parts

09/29/2026

The curved piece is doing its best to dominate the photo, but the tiny block in the middle keeps stealing our attention.

It’s the smallest part here, yet it still packs in a rectangular opening, small holes, and multiple machined faces.

A good reminder that in machining, small and simple are not synonyms.

Have something equally specific in mind? Request a quote: https://www.approvedmachining.com/request-for-quote

09/24/2026

Quick quiz:

What do you call a turning center that can machine round parts, then mill, drill, tap, and handle off-center features without sending the part on a full shop tour?

A) An overachiever
B) A very expensive multitasker
C) Our new Haas Automation, Inc. ST-28Y CNC turning center
D) All of the above

We'll go with D.

With live tooling and Y-axis machining, the ST-28Y can mill, drill, and tap a part without it ever leaving the machine, even on complex off-center features.

For customers, that usually means less handling between operations. It also tends to mean fewer delays and more consistency from one part to the next.

We're sharing more about our expanded CNC milling and turning capacity here: https://www.approvedmachining.com/blog/approved-machining-expands-in-house-cnc-milling-and-turning-capacity