<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto">Jon, yes I did and it was no problem, especially for you. <div>Hank<br><br><div dir="ltr">Sent from my iPhone</div><div dir="ltr"><br><blockquote type="cite">On Sep 2, 2022, at 8:55 AM, Jon Wallace via Personal_Submersibles <personal_submersibles@psubs.org> wrote:<br><br></blockquote></div><blockquote type="cite"><div dir="ltr"><div class="yahoo-style-wrap" style="font-family:times new roman, new york, times, serif;font-size:16px;"><div dir="ltr" data-setdir="false">Anyone out there normalizing their acrylic?</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">Section 15 of Stachiw's Handbook of Acrylic is dedicated to stress relieving processes for acrylic viewports. Stachiw states that such stress relief is required to reduce the premature crazing and failure of acrylic surfaces. Section 15.2.1 discusses "normalization" of the material and how it both relieves stress and changes the physical properties of it. The amount of time required to heat, bake, and cool the acrylic material depends upon thickness, but is lengthy in all cases. I have reached out to numerous acrylic molders in New England and found that none of them have ovens that meet the technical requirements for proper normalization or annealing as described by Stachiw. That leads me to the conclusion that I'm probably/definitely going to have to build my own oven for such purposes. I think Hank did build such an oven but I haven't heard of anyone else doing so.</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">Jon</div></div><span>_______________________________________________</span><br><span>Personal_Submersibles mailing list</span><br><span>Personal_Submersibles@psubs.org</span><br><span>http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</span><br></div></blockquote></div></body></html>