Hi Kilele,
I'd like to thank you for putting up the question to begin with.
Looking at the query, my first thought was using multiple charts, but that would be excruciating and hence ignored it.
Today it just stuck me, that excel already provides a grid which can be put to use to draw to SCALE.
So got to work, (probably with the same inspiration Chandoo has, that one day excel will make my coffee too) and an hour later the solution prevailed.
So here goes,
I call it the Engg drawing sheet; except no cello tape(reminds me of my Engg drawing classes)
It uses conditional formatting.
Each cell has been formatted so that it highlights the relevant border based on the input.
eg with N the North border is visible (activated)
When i tried it filling multiple cells with N,E,W,S was time consuming, so challenge was how to make it easier.
Elbows were added to definition.
Next were the building blocks or the elements which would be commonly used looking at your drawing
Lines of 5,10,15 unit length came first.
Being a hydraulic drawing, tanks would be used frequently, hence a definition for the tank.
Pointers added so that formatting would not have to be repeated
The workbook
http://rapidshare.com/files/403157408/Engg_Drawing_Sheet.xlsx.html
has 5 sheets
1. definition
2. elements
3. drawing
4. output image ;of a portion of the sheet;on a reduced scale for easy viewing
5. Blank sheet for you to try out
I found it quiet easy to sketch, is pretty accurate as all lines are to scale
its easier if the element sheet is taken in a separate work book so that you can 'alt-tab' to copy and paste what you require
In the drawing sheet I've set the font to a light grey, for final print format it to white to make it invisible
http://www.flickr.com/photos/47177133@N03/4737978012/
Do use it and let me know if it suites your use