Tools I use. Yours to use too.
Small calculators for the questions that come up every week on the floor and at the desk. They run in your browser, nothing is saved, and they are the same math I use on real parts. If one of them saves you a scrapped part, tell me.
Bend allowance & flat pattern
Same math I use for laser-cut and press brake parts. K-factor 0.44 is a good start for air-bent 5052 and mild steel with a bottom V of about 8x material thickness.
Real K-factor depends on tooling, V-die width and material. Bend a test coupon and back-calculate before you commit a production flat pattern.
Tap drill & clearance hole
Tap drill sizes are for about 75% thread, which is what most shops run. Clearance is the normal fit.
For cold-form (roll) taps the drill is larger; use the tap maker's chart. Die cast and molded parts get a cored hole with a lead-in per the caster's table.
Thread engagement check
How deep does a tapped hole need to be so the bolt breaks before the threads strip? Uses the NASA RP-1228 pullout relation with the bolt's full tensile strength as the load.
This is a sizing check, not a certified analysis. Shear strengths are typical values. Add depth for chamfers, incomplete threads at the bottom of a blind hole, and any plating or coating.
Die cast quick check
A first pass at the questions a die caster will ask about your part. Walls, fillets, and draft, checked against common NADCA guidance.
- ✓Nominal wall 0.1" is in the normal range for aluminum die casting.
- ?Thinnest wall is 10% under nominal. NADCA guidance is to hold walls within about 10%. Thin spots misrun and cold shut.
- ?Thickest wall is 40% over nominal. Heavy sections shrink, sink, and hold porosity. Core them out.
- ✓Fillet 0.06" meets the typical 0.060" general fillet.
- ✓Inside draft 2° vs outside 1° follows the 2:1 guideline.
- ?A 1.5" deep pocket with a 0.1" wall is a deep, thin-steel feature. Add draft, add radius, or split it so the die steel between walls stays strong.
General guidance for aluminum die castings. Zinc and magnesium allow thinner walls. The caster's own tables and a real DFM review win over this every time.
Corner IQ
Track Maps · Telemetry · Race Engineering
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Quoting sheets, inspection checklists, part lookups, dashboards. Tell me what you track in a spreadsheet today.
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