A scar is testimony to the incredible power of our bodies to heal. As soon as

A scar is testimony to the incredible power of our bodies to heal. As soon as a wound occurs, our skin tries to close it as quickly as possible, to prevent infection. The body gets to work rebuilding tissue by sending out fibroblasts, cells that make collagen, which is the support structure of the skin. However, in this race to repair itself and replenish tissue, new cells aren’t always laid out in the neat pattern that makes up the rest of the skin — resulting in a visible scar. Brainy body: A scar is testimony to the incredible power of our bodies to heal. As soon as a wound occurs, our skin tries to close it as quickly as possible, to prevent infection If the fibroblasts make too much collagen, this leads to a raised scar. These fall into two common types: keloid scars, which are red, thick and bumpy and spread beyond the original wound; and hypertrophic scars, which are also raised and red, but more contained, and often follow surgery. We don’t know what causes keloid scars to form, and anyone can get them after any type of wound, but they are more common on the upper chest and shoulders and in people with darker skin. A third common scar type is atrophic. These pitted scars...

So you’re looking to buy your first 3D printer, and your index finger is quivering over

So you’re looking to buy your first 3D printer, and your index finger is quivering over that 300 US Dollar printer on Amazon.com. Stop! You’re about to have a bad time. 3D printing has come a long way, but most 3D printers are designed through witchcraft, legends, and tall tales rather than any rigorous engineering process. I would say most 3D printer designs are either just plain bad, or designed by a team of Chinese engineers applying all their ingenuity to cost cutting. There are a few that are well designed, and there is a comparatively higher price tag attached. I’ll start by going through some of the myths and legends that show up in 3D printers. After that I’ll go through some of the common, mostly gimmick, features that typically hinder your printer’s ability, rather than adding any useful function. Next I’ll go onto the things that will actually make your printer better. Finally, I’ll add some special consideration if you’re a beginner buying your first printer. Most printers have very mechanically weak designs. You will never be able to just throw a spindle on 99.9% of 3D printers and get a CNC machine. 3D printers are typically not designed to take loads, they are no...