How do I actually know my plastisol is cured? (stop guessing)

Question

This tripped me up for way too long, so here's the plain version for anyone fighting prints that crack or wash out.

Plastisol cures at a temperature, not on a timer. Standard plastisol needs the entire ink film to reach about 320°F (160°C). Your belt speed and dryer length only exist to get it there — "20 seconds in the dryer" means nothing if the ink never hit temp.

How to actually check it:

Temp gun the ink, not the shirt. Run a printed piece through and hit the ink deposit (especially a thick spot like a white underbase) the instant it exits. Thick deposits lag — if the thickest ink is at temp, you're good.
Better: a donut probe / temp strip that rides through the dryer on a shirt and logs the peak the ink actually saw.
Confirm with a stretch + wash test. Stretch a cured print — cured plastisol flexes with the fabric; under-cured ink cracks. Then wash-test a sample before you trust a run.

Belt dryers drift over a day as they heat-soak, so re-check, especially on heavy deposits and 50/50 blends.

If you want the longer walkthrough with the cure-window details, the help center has a full guide: https://kontraktr.io/help/production-queue

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Kontraktr Team · Accepted Answer

Great writeup. To add the one thing that catches the most people: the thickest part of your print is the last to cure. A white underbase or a heavy athletic-number print can still be raw in the middle while the thin areas are done. Always probe the heaviest deposit — if that's at cure temp, everything thinner already is.

And yes to the wash test. A stretch test tells you it probably cured; a wash test tells you it did. On a new garment or a new ink, do both before the production run.