Siraya Tech Tenacious Flexible Resin High Impact Resistance 405nm Clear 1000g Review (2026)

What this resin is

This is Siraya Tech's Tenacious flexible resin in clear, a 405nm UV-curing photopolymer sold in a 1000g bottle for LCD and DLP resin printers. Siraya Tech is a specialty resin brand known within the hobby for formulas aimed at flexibility and impact resistance rather than the standard grey or clear resins most printers ship with, and Tenacious is its flagship flexible line. According to Siraya Tech, the clear Tenacious formula is rated around 65D on the Shore hardness scale, which sits in a middle zone that is noticeably softer and more elastic than a standard resin but still firmer than a fully rubbery flexible resin.

How flexibility depends on part thickness

Siraya Tech describes Tenacious as flexible when printing thinner, finer objects, but exhibiting greater strength and stiffness when printing larger, thicker objects, which is a real characteristic of the resin rather than a limitation. That means the way a print behaves depends heavily on wall thickness and geometry: a thin snap-fit tab may flex noticeably, while a solid thick block of the same resin will feel considerably stiffer. Siraya Tech's data lists a tensile strength around 24 MPa and an elongation at break in the 50 to 70 percent range for the clear and Obsidian Black versions, both of which reflect genuine give under stress rather than the brittle snap typical of standard resins.

Using it as a blend-in additive

One of the more common uses for clear Tenacious among hobbyists is blending a portion of it into a standard or tough resin to add flexibility and impact resistance to an otherwise brittle formula, rather than printing an entire model in Tenacious alone. Printed by itself, Tenacious stays quite soft for rigid structural parts, so anyone wanting a fully rigid result should either blend it with a stiffer resin or choose a dedicated tough resin instead. This blending approach is part of why Siraya Tech markets Tenacious the way it does, as a specialty additive resin as much as a standalone material.

Handling, cleanup and curing

Flexible resins, including clear Tenacious, are generally stickier and messier to wash and cure than standard resins, since the softer cured chemistry does not release cleanly from wash solutions or gloves the way a rigid resin does. Siraya Tech recommends printing and curing Tenacious in a room above 25C, since colder ambient temperatures can make the resin cure less predictably and leave prints tackier than expected. Buyers should plan on extra wash and cure time compared with a standard resin, and expect some trial and error dialing in exposure settings, since flexible resins in general are less forgiving of under-curing than rigid ones.

Value for a specialty resin

Siraya Tech's pricing on Tenacious sits above basic standard resins but is in line with other specialty flexible and tough resins on the market, reflecting its position as a niche product rather than an everyday choice. For hobbyists who print mostly rigid display models, this is not a resin to buy as a primary material; for anyone regularly blending resins to fine-tune toughness, or printing thin flexible features like straps, hinges or gaskets, Tenacious remains one of the more established options from a brand with a strong reputation among resin printing enthusiasts who value predictable results.

Frequently asked questions