~Cutting, Marking, Measuring, and Sanding dowels~ Monday 18/04/11

Today I did measure, mark, cut, and sand the

dowels. I needed 8 dowels more. So first, I got

long stick wood, and measured 7.7cm each. I

changed my plane. Before the dowels has to be

8cm, but I got small then 8cm dowels, so I

changed to 7.7cm. After cut the dowels, I

checked if the dowels

are all same size. It

was not same size

still. So I have to sand

it. I used flat file to

sand dowels, but I

thought it would take

long time to sand whole dowels. So I asked Mr.

Anderson to use disk sander for sand the dowels

faster. He said ‘yes’. So I started to measure

whole dowels to 7.5cm, and use pencil to

marked. After marked whole dowels, I got goggle

and hair band to use disk sander. Also after I got

20 dowels. I calculated how many dowels do I

use. First, the bases

are circle, so I

calculated

circumference of the

base.

How to find circumference?

2πx x=radius of circle

My base of radius= 7.5cm

Formula: 2π7.5= approximate 47cm

So the circumference is 47cm. It not finish yet, then I calculated how

many dowels can be put in the around the circle base.

The Formula is: circumference ÷ (2cm+1cm)

2cm is an opening between the dowel and the dowel. 1cm is dowel of

width.

The answer is approximate 16 dowels. So my plane is the opening

between dowel and dowel will be 2cm.

NEXT

I didn’t have time to check the dowels length size. So next class I

have to check the dowels size, and if the sizes are all same, I want to

mark in base to make hole for put these dowels. But if the sizes are

not same, I will repeat measure, mark and sand dowels.

Emotion

I thought math formula is REALLY useful!! Because today, I wanted to

find how many cm do I have to open and mark for drill positions, and I

used math formula to find that.

AOI-Human Ingenuity

Today I used math formula to find circumference of base. Today I

thought math is really important for DT. I did good invention to do this

project.