Wordless Wednesday

Out of This World

Commander Chris Hadfield of the Canadian Space Agency will be returning to earth this evening from the International Space Station with the rest of the crew of Expedition 35.  We wish them a safe return.  For his farewell to the ISS, he recorded this:



I urge you to go to the YouTube website to view this in full-screen - the video is amazing.

This is one of a few videos that he's posted from the ISS and I think that they are incredibly important.  They let us all share in the wonder that living in space truly inspires.  It's not just about the science and research that goes on aboard the ISS, but the inspiration that the men and women who make this all possible are instilling in future generations of scientists, engineers and space-farers of the future. 

These men and women are the voyagers of today - blazing a path for the rest of our futures.  The "boats" may have changed, but the mission hasn't.

It is amazing, and it is awe-inspiring.

Wordless Wednesday

Say your prayers...

We keep a set of pantry shelves in the basement for those items that keep well and that we use frequently.  Because we tend to get mice in the house during the fall and winter, I set live catch traps with peanut butter, like this:

Usually, I have pretty good luck catching the mice and sentencing them to "transportation".  The get taken across the river where I figure they become part of the food chain - or not, depending on their luck and skill.  We do have a soft spot for rodents in this house as DS and DD have a pair of gerbils.  We also have some outdoor rodents that we're friendly with - I'll post more about them at a later date.  At any rate, we've had reasonable luck with this method.

Not of late, however.  Traps have been tripped with no mice in them.  Less than a 10% success rate catching the little buggers.  Finally, DW called me down to the basement one evening - LOUDLY.  The mice had been into all kinds of things on the shelf - from shredded sweetened coconut to powdered sugar.

What a mess.

Time to take on some more aggressive methods.

So, we've resorted to capital punishment for the mice.

Electric traps.

 

Basically, like the live traps, the mice are baited with peanut butter in the trap, walk in and get zapped.  These traps worked really, really well.

Mice, say your prayers.  

Fortunately, not all of the mice went into the electric traps - some of them who appeared to be less savvy were hitting the live traps and went on to be free-range mice.  You've got to admit - they're cute, but they're only cute because they're not in the house!

Wordless Wednesday

Tech Tip Tuesday

 

I got a comment from a blog reader on a previous Tech Tip Tuesday that I did on some folding sawhorses for my class.  On the following Saturday, I posted the material list and the design.  This is that comment:

Peris said...

 

Great post. Your saw horses look wonderful and easy to make. My problem is that I want to make mine ar 94cm (37") tall and I don't know the formula you are using to determine the outer and inner legs height, and also where should I drill the holes. Your help would be greatly appreciated.

Well, we're going to dig into your high school trigonometry that you've all either forgotten or really want to forget.  It's fairly easy and the math isn't too scary.  This is all about triangles.

Let's take an end view of the sawhorses and what do we see?  A triangle.  The included angle between the legs is 40°.

 

But, we want to be able to change the height of the sawhorse legs to customize the original design.  We need to simplify things a bit more from our first triangle.  We know that it is symmetrical about a vertical line.  We wind up with a right triangle that is 20°:

 

Now we're going to strip away the left triangle that we don't need:

We know what we want to change for "X", but need to figure out what "Y" is.  So, we're going to refer to the Indian God of trigonometry as one of my teachers used to refer to them : Sohcahtoa.  That's a mnemonic to help remember the trigonometric equations:

SOH - Sine(angle) = Opposite ÷ Hypotenuse

CAH - Cosine(angle) = Adjacent ÷ Hypotenuse

TOA - Tangent(angle) = Opposite ÷ Adjacent

In this case we know the angle and the adjacent leg (X), so we'll use the Cosine function and solve for Y.  So, when we simplify the equation to solve for Y we get the following:

Y = X ÷ Cosine(20°)

Let's say we're making the sawhorses 9" taller, like Peris, so our X=9

Y = 9" ÷ Cosine(20°)

Y = 9.578"

So, Peris would want to add 9.578" (or the nearest fraction - 9-9/16") to the length of all of the legs and the distances for the hole locations.  He'll need to tweak the amount of material needed and because the legs are getting a bit tall and spindly, an additional support between the legs might be required and the position moved up or down.  I placed them where they "looked right" - about 1/3 up from the bottom and down from the top.

Have fun!

It's that time again...