Saturday's sketches...

Hy, I have a boring part-time job every saturday. While some days are busier than others, there's always some lapse when nobody's buying or asking anything so I use that time to sketch some random lines, try to draw some object from imagination, or using some of the things around me as reference. My biggest goal aside from not dying of boredom is to increase my skills in shading with ballpoint pens, hence I won't be paying much attention to perspective (actually i'm attempting to use some kind of isometric projection in most of them, but of course it's all freehand drawing, otherwise I wouldn't call them sketches).
And it's some small notepad that I have, so this will continue for as long as there are white sheets left to draw.

The spring-like structures to the right were my first Saturday sketches, they were both made on July 22nd. Then I started trying to draw some screws, nuts, and bolts, these are all from July the 29th.

After that, more customers started to visit our store so i was able to make only one sketch every Saturday for the whole of August, staring with this:

Do these screwdrivers count as one or two sketches? Anyway, none of them is well proportioned...

Then I went for a much more complex subject, but it didn't come out as i expected for there is too many unnecessary lines when I'm sure the crystal surface could be suggested in a more simplistic and effective way...

So I tried again, but this time I wasn't able to do much more than the general structure of the lightbulb...

And I added more detail to it next Saturday, but i'm still unhappy about it -actually the first one was much better than the second- so chances are I will be drawing more lightbulbs in the future, the photograph shows both versions for comparison.

PS: please notice that i'm not a native English speaker, so please forgive (and make me know about) any mistake within this or following posts, thanks in advance.