How polymatt dries resin-printed heat shield coupons with BLOWZER

A maker who wants to break things properly

polymatt makes engineering videos the hard way: he designs, prints, machines and wires everything himself, then tests it until it fails. This one starts with a real-world mystery. The Orion capsule's heat shield came apart during Artemis I's return, NASA's own ground tests never reproduced it, and the cause took two years to find. Matt wanted to know whether he could make the material, Avcoat, in his workshop and reproduce the failure.

Printing the honeycomb

The original Artemis I shield packed the ablative material into a fiberglass honeycomb, so that's what he builds. He models parametric coupons in Shapr3D, each about 20 millimeters thick with three holes for thermocouples at set depths, and prints them in Formlabs Rigid 10K, a glass-filled resin that stands in for fiberglass.

Resin prints come off the printer wet. They go into an isopropyl alcohol wash, and then they have to be dried, which, on a part made of dozens of small cells, is the tricky bit. "If you don't get into all these little crevices and get all of the alcohol and the excess resin out," he explains, curing goes wrong.

Eleven seconds with the X6

That's where the BLOWZER X6 comes in, without a word about it. In gloved hands over a purple-bottomed tray, he presses the front of the X6 straight onto each washed white coupon, its blue LEDs lit, and turns the part under the airflow so the air pushes through every cell. One coupon after another, then into the Form Cure.

It's a quiet, practical moment: the tool he reaches for when a part has more crevices than a paper towel can reach. The X6 is on screen for about eleven seconds of a long build-and-burn video and is listed in his gear list as his air duster.

The voice-over also shows why the step matters. One batch had resin left inside, and it leaked out during curing and stuck the coupons to the plexiglass plate. "Luckily I'm an old pro at screwing up," he says, and a trip to the freezer let him scrape them free.

What happened next

With the coupons cured, he mills copper and aluminum holders on the Makera Carvera, builds an e-ink thermocouple logger and mixes his own Avcoat by kneading it like dough. Then come the torch burns: a direct burn and a skip-entry burn, heat on, heat off, heat on again. The skip-entry coupon shattered its honeycomb, while the longer continuous burn came through intact, the same failure NASA found. His one-line conclusion: "Less heat broke the heat shield."

Why it matters if you print in resin

Every resin printer knows the problem. Alcohol and uncured resin hide in holes, lattices and internal channels, and whatever is left there spoils the cure. Blowing each part dry before it goes under UV is the cheap insurance. Use gloves, work over a tray, and choose the mode and nozzle that suit the part.

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