Optical Flow Meter based on Time of Travel Method

 
This article is about an DIY optical flow meter for Measuring Urine Output. But you can measure also water flow.

DIY HDD conversion to microhematocrit centrifuge

There are so many DIY projects out there that use old HDDs.

I liked the idea of converting HDD to a centrifuge. So I made my version by converting an HDD to a microhematocrit centrifuge.

Microhematocrit is a procedure for determining the ratio of the volume of packed red blood cells to the volume of whole blood by centrifuging a minute quantity of blood in a capillary tube coated with heparin.A centrifuge spins the sample at a very high speed to achieve the separation.

Another sewing awl

This is an idea of how to make a sewing tool (DIY).

It's a useful hand tool for lockstitches in difficult to reach areas. 

Recently I had to fix a pair of shoes, so after some googling I found that there are some simple and interesting  mechanical devices out there.