The $200 Million Mistake Hiding in Chicago’s Skyline

I need to remember to take my umbrella the next time I got to Chicago in case a 350-pound Carrara marble slab comes tumbling down from a building.

The building in question - now known as the Aon Center - was originally clad in the aforementioned Carrara marble, using panels that were 1.25 inches thick.

Apparently marble isn't terribly durable when going through extreme freeze-thaw-hot-summer cycles with each temperature shift leading to tiny cracks developing which allowed water to get into the cracks and freeze - like pot holes forming on the side of the (initially) world's 4th tallest building. 

Eventually, all the marble panels were replaced with granite which seems to weather the Chicago winters far better and is less prone to hurling itself off the building's facade and onto the tourists looking up with their mouths agape. 

Learn to Build With Cardboard! STRONG, Waterproof, and Free!

We've seen NightHawkInLight around these parts before - or at least we've heard his voice.

In this video, he posits a few simple rules for building with cardboard...

• Direction matters - cardboard is not equally strong in all directions
• Layer for strength - laminate/glue multiple layers together for a strong material
• Glue then trim - glue the layers together before trimming them to size
• Wheat paste is awesome - It's an environmentally friendly glue - which he shows you how to make.
• Reinforce edges - Trim and fold over the cardboard facing to reinforce the edges
• Mixed materials - Small amounts of wood can be added for extra, targeted strength
• Face jointed reinforcement - again with the wood reinforcement
• Surface hardening - more wheat paste but as sizing not as glue
• Securing joints - use toothpicks to hold pieces in place until the wheat paste sets
• Utilize tensile strength - cardboard is strong in tension; use its strength
• Templates save time - if you're making dozens of the same piece, use a template
• Splice sheets perfectly - He shows a way to thin both sheets and splice two together.
• Fold sheets cleanly - sort of like the splicing
• Papercrete fiber recycling - Hey, a composite made of composites! This one is wheat paste and paper pieces - not ice.
• Panel jointery - Again, more tips for joining pieces together
• Improved jointery - seriously, more joining tips

Then he gets to how to waterproof the cardboard. One of the methods he suggests involves shellac - which I've blogged about before and is very much not vegan-friendly - with beeswax. The other is hot glue, beeswax, and mineral oil and looks to be way gloopier.

The last part of the video explores ways to make the waterproof coating UV-resistant, something that I never would have thought to be concerned with.

Honestly, this video is way more detailed about cardboard building than I ever would have guessed could be done.

Now I just need to go back in time and get grandpa to bring home some boxes from his Inland Container job in the 70's.

PYREX vs pyrex - What's The Difference & Why It Matters

About thirteen minutes into the above video, the YouTuber shows a screenshot from the Corning Museum of Glass's website...

...that asks whether the PYREX stamp in all caps definitely tells that the PYREX item was made with borosilicate glass - something I'd been told was a definitive tell.

According to the Corning Museum website, "the change from upper to lower case signified a re-branding of the trademark Pyrex®  in the late 1970s but is not a conclusive way to determine, historically, what type of glass formulation the product is made from."

So that's apparently out the window.

The video does go on to explore the various other ways of differentiating borosilicate from soda lime pyrex: the blue tint, visibility in mineral oil, even a not-very-scientific drop test onto a patio block.

In the end, the best that the host came up with was to look for a made in France mark. Apparently the French know to use only borosilicate glass.