Design & DFM
Designing Machined Parts for Tool Access
A feature a cutter cannot reach is a feature that costs money or cannot be made at all. How tool reach, pocket depth and radii decide the price of a part.
2026-09-19·3 min read
What this topic covers
- Tolerance strategy - Where a tight tolerance earns its money, and where it only adds cost - plus how to size a stack-up before release.
- Geometry rules - Corner radii, pocket depth, wall thickness and the features that force a part into a slower, more expensive process.
- Drawing quality - Datums, revision control and the four things that must be on a drawing before it can be quoted unambiguously.
- Commercial impact - Which design decisions change the price class of a part, and which only change it by a few per cent.
Articles
All Design & DFM articles
Design & DFM
Threaded Inserts: Assemblies That Survive Being Taken Apart
A thread cut directly into plastic or thin sheet will strip. Heat-set, moulded-in and press-in inserts, and how to choose the one the joint actually needs.
2026-09-19·4 min read
Design & DFM
Fastener and Fitting Selection for Machined Assemblies
Threads, inserts, clearance fits and standard versus custom fittings: how to specify the joints that hold a machined assembly together.
2026-09-18·5 min read
Design & DFM
A DFM Checklist to Run Before You Order Parts
Twelve checks that catch most manufacturability problems before they reach the machine shop.
2026-09-11·8 min read
Design & DFM
How to Set Machining Tolerances Without Overpaying
Set tolerances feature by feature so you only pay for the precision the part actually needs.
2026-09-02·8 min read
Most of these notes come from quotations that changed after a review - which is the point. A drawing that is cheap to make is not a compromise on function, it is a drawing where the tolerances and the geometry were chosen deliberately.
Other topics in the notes
Send a part for a manufacturability review
A DFM review before quoting usually finds something worth changing. Send the model and the drawing and we will say what we would change and why.