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Disinfection of PPE such as N95 respirator masks

An article from Consolidated Sterilizer Systems starts with: "With the global Covid-19 pandemic everywhere in the news, many healthcare professionals and concerned citizens are grappling with the shortage of respirator masks, vital tools for ensuring that healthcare workers are not infected by the people they’re trying to help."

The article suggests that microwave steam based disinfection has been effective at disinfecting, specifically removing H1N1, from non-metal N95 respirator masks. Here is a 3D grid that can be placed into a glass tupperware container filled with some water and then put into a microwave. Don't put anything with metal into the microwave. Alternatively, you can use this grid in the oven as well; see the description in the article.


This grid is 4.4" square and 1.25" tall. It's easy for me to produce any other dimensions.

The log reduction for microwave steam is around ~5, i.e. 100,000 times less viable virus. The article does not give a protocol. I put the filter in the microwave for 3 minutes which was sufficient to boil the water for 2 minutes. For oven steam, the protocol requires 3 hours under warm water steam and let to a slightly smaller log reduction of ~4.8, i.e. 63,000 times less viable virus. This requires an oven that has good temperature control.



Disclaimer: It is unclear if this is effective for disinfection. Even with high-temperature filament, it is unclear if a 3d printed grid is appropriate for this application.
Categories: Hacking

Forging A Viking Broad Sword: from start to finish


This is a video completing about two years of work in creating a single-edged pattern-welded sword or seax that could plausibly have been created during Viking times. It shows alls steps from assembling pieces of steel, twisting and forging until the sword blade is complete and tested with a simple cutting test.

It’s about 30 minutes long and shot on a Sony FS7. It’s 4K and color graded for high-dynamic range (HDR).
Categories: Forge Diaries
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When data contradicts security best practices

Mudge and I had the opportunity to talk about Security at Stripe Sessions. Our key takeaways:
SMS Challenge works
Password complexity doesn’t work
Security products can make it worse
You can measure security
"Always update," needs updating




Enjoy!
Categories: Security
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Pattern Welding Explained as Wearable Art


Pattern-Welding was used throughout the Viking-age to imbue swords with intricate patterns that were associated with mystical qualities. This visualization shows the pattern progression in a twisted road with increasing removal of material. It took me two years of intermittent work to get to this image. I liked this image so much that I ordered it for myself as a t-shirt and am looking forward for people asking me what the image is all about. If you want to get a t-shirt yourself, you can order this design via RedBubble. If you end up ordering a t-shirt, let me know if it ends up getting you into any interesting conversations!

Categories: Forge Diaries
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Fabricating a Trellis


The garden needed some trellises for roses. We came up with a circle design and are fabricating it in the shop. Mild steel bar is bent into many different ring sizes and then put together into a fairly large trellis. I am also showing some really beautiful slow motion shots of welding and grinding in high dynamic range.
Categories: Forge Diaries
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Support my videos on Patreon!


Add your support on Patreon to help me create more videos. Your support will help with materials, rent as well as other equipment, e.g. cameras, lights, software, etc. It is not required but appreciated. Due to time constraints I can make no promises on how often I will be able to publish new videos but my plan is to continue producing videos as long as people find them interesting.
Categories: Forge Diaries
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