2026-01-05 – Weekly Optician News : Preventing AR crazing tips

Last week in the forum, discussions ranged from practical tools to improve day-to-day optician tasks to the technical intricacies of lens production and fitting. Members shared valuable insights on preventing anti-reflective crazing during frame heating and explored the historical origins of materials like CR-39. There was also a lively exchange on strategies to reduce lens remakes, highlighting a continuing interest in efficiency and quality improvement.


This Week’s Hot Topics

Best LED handheld magnifier for daily demos
Opticians are weighing in on the most effective LED magnifiers for conducting product demos. This thread is a great resource for anyone looking to enhance their customer service toolkit.
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CR-39 name origin
Curious about how the popular lens material, CR-39, got its name? This thread dives into its history and significance in the optics field.
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Why your near PD is smaller
Understanding the difference between near and distance PD can be critical for precise lens fitting. Find out why these measurements differ.
Read more here

Preventing AR crazing during frame heat
A common issue, AR crazing can affect lens durability. Check out the shared tips on how to avoid this problem during frame adjustments.
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Pupilometer stage fright at 2:15
An amusing yet informative discussion on overcoming pupilometer challenges, especially under time pressure.
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Soft toric rotation quick-check
For those dealing with soft toric lenses, this thread offers quick methods to ensure proper lens alignment.
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CE plan that cut remakes 18%
Explore how one optician’s continuing education plan led to a significant reduction in remakes. A valuable read for anyone involved in process improvement.
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My edger thinks PD is a suggestion
Discuss the quirks of edging machines and share solutions for when equipment doesn’t quite follow the rules.
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Tools you trust for scleral sagittal height
This thread is a must for those fitting scleral lenses, offering recommendations for reliable measurement tools.
Read more here


Looking forward to another week of engaging conversations and shared expertise. See you on the forum!

I’ve cut down AR crazing during frame heating by going dry only — hot-air warmer at about 230°F (110°C) — and shielding the lens with a folded microfiber while I “heat the frame, not the lens” in 3–5 second bursts. CR-39 forgives a touch more, but with poly I won’t push past that temp or use salt pans since moisture shocks still bite.

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I keep an old metal demo lens as a heat shield and “pre-warm” the whole front with low hot air for 3–5 seconds before focusing on the eyewire — cuts the temp shock that crazes AR, especially on high-index. For bigger bends I pop the lenses and heat the chassis only; microfiber alone wasn’t enough on mirrors for me, @ashton_67. Kinda like warming a cold glass before you pour in hot water — same idea.

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@MartaV I keep a pocket IR thermometer at the bench and stop as soon as the lens surface reads about 45–50°C; that alone has nearly eliminated AR crazing for me. If I need a little more give, I back off the eyewire screw and work the rim cold before snugging it again.

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Switched to a low-temp bead pan (about 70°C) and mask the lenses with two layers of Kapton tape — cheap, clean peel, and it blunts that coating shock. If a zyl is stubborn, I pop the lens and shape the eyewire first, then seat it cool; paired with @csanders10’s temp checks, coating stress is gone and it saved me a couple remakes last week.

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Nothing kills me like seeing spider lines after a quick heat tweak. I back off the eyewire screw a quarter turn before warming the front — relieves clamp pressure as the zyl expands, then snug it after; costs nothing and takes about 10 seconds. For nylor I pop the cord first, and on 1.67 I skip in-frame tweaks and use a lukewarm water bath instead, @ashton_67.

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I press a cool stainless spoon against the lens while warming the endpiece — like a little heat sink, and it’s cut my AR crazing way down; think ‘heat the frame, cool the lens’. Just don’t make the spoon ice-cold on older glass or fragile stacks, or you can shock it — anyone else using a heat-shield trick?

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