Wednesday, November 23, 2011

ZNSE arrival!

The postman brought a great letter today! Inside was a little 1.5mm by15mm ZNSE window with AR coating.

I was very kindly donated this window by Guy at Orcon Technology. Thanks Guy! He sells all sorts of great laser bits on Ebay. Go and visit his Ebay shop:

I need to cover the hole in my OC mirror, so this is what I did with it today.

Above you can see the brass mount which holds the OC mirror-
-Its gold on the other side. I cut that mirror from an over head projector mirror. I figured it would be the flattest glass I could get. As any imperfections would be very big when the projector was working. So I guessed they would need to be starting with pretty flat glass to make their mirrors.
That mirror is JB Welded to the brass fitting.
On the left of that pic' is the ZNSE holder. I cut that on my homemade CNC with a 1.6mm single edge cutter. It came out very well. The Window is sitting in a little recess. It should be sitting on an o-ring. But I forgot.

There it is assembled.The pictures are pretty much self explanatory, I think. By the way, I have not tried pump this down yet. And I have not used any grease on the o-rings. I would rather see if I can get away without it. Silicone is a creep.

Tuesday, November 22, 2011

Beginings of a CO2 laser.

I couldn't resist anymore. I've started building a CO2 laser.
Is my new diffusion pump finished? No.
Is my new belljar thing finished? No.
Is my watercooled magnetron finished? No.

To start here is a picture of the laser as it stands today. I will go into construction details as I go along.
From the bottom up!
The base is MDF, to which I have bolted two pieces of Aluminium T-slot stuff I got out of a skip a few years ago.(3* m6 bolts on each side) It was part of an office partition. I unbolted the carpet covered wall sections and was away with the T-slot section!
I was going to use this stuff on the base of the CNC machine but I didn't really have enough, so I stacked it up in the corner!
In this picture there's a lot to see.
First, the brown stuff which the whole laser is mounted to is 'Tufnol' or paper reinforced Bakelite.
This is a very interesting material and the first time I had ever worked with it. It is dense, ridged, machinable and very electrically insulative and very old. Many electrical fittings are still made of it.

If memory serves me air breaks down at 3kv per MM(corrections welcome!)
So I tried to make sure I had at least 15mm between anything conductive near the electrode and T-slot.

Beginings of a CO2 laser.

Where's the interesting stuff?

A bit of a philosophical ramble now.
I am reading a book at the moment which is crystallizing some thoughts I have been having in the last couple of years.
This rant is as much for my own mental organizing as for anybody out there to read!

A false notion which I have believed for ever, consciously and/or subconsciously is that: Great ideas happen because they are great.
Or to be said another way, a brilliant concept must inevitably come to pass due to its high quality alone.

This, I have now decided is all bullshit. Crappy ideas are just as likely to see production.
It all has to do with the structure of their execution.

Why is this?

I have wondered why so many of my own great ideas are gathering dust on shelves in my workshop.
I supposed that ideas got shelved because they turned out to be not such good ideas or became irrelevant for some reason or another.

I now know these are not necessarily the reasons.

In recent years I have been amazed at the fruitfulness of some people. Those works being of varying quality in my eyes but nevertheless work that is completed.

Yet so much of my work lies abandoned.

What words would I use to define a great idea when I have it? Does the list include the words: new, stimulating, exciting.

The question I then asked is: In what way has the idea changed now? Or what is different about the idea now, as compared to when they were first conceived.
What about the idea is missing now, which initially created such energy?

I once put it down to the fact that I am a bit of a perfectionist. I am interested in high quality and workmanship in what I do. And I would always be procrastinating by getting a part or learning new a technique.

The truth is: Creative people get high on NEW ideas.

Ideas generate very positive feelings. It is a natural urge of any creative person to chase those feelings, even be addicted to them. When what we are doing is not getting us high we go back to doing the thing that gives us the buzz!
Thus, once an ideas is concieved and acted on to a greater or lesser extent, the excitment of the new concept fades, and we move on to the next great idea!

So what do we do about that, now that we know?

Cold turkey. Every project will have a comedown. You must expect it and realize what you are experiencing. The idea is still brilliant, it is just old and farmilliar. You must control your wandering eyes and be faithful to it.
This is a battle against your own nature. It is difficult.

Some people are lucky enough to be very self controlled. They can create their own motivation even after the initial high has worn off. For me, that's not the case.

One possible way is-
Impose EXTERNAL motivations which tick my obligation boxes.
Guilt tripping, nagging, promises, deadlines, these make me feel obliged to do things. Deep within myself there is an image of a person of good character which must be protected at all costs. Well there's a motivation.

So follow through is not in the nature of a creative person. So I must be aware that even though I may not be enjoying myself and what I'm doing is not giving me fantastic satisfaction, it may still be the right thing to be doing to get an idea to completion.

So it seems it is not the quality of the idea that is important, it is 'follow through' that is important. And the awareness of when I have reached that phase the idea's life.

Tuesday, November 15, 2011

I was just trying to reply to a comment on the sputtering video and I couldn't get it to work, so this post is a bit personal!

Hi Elena!
To be honest the setup is very low-tech! The magnetron is just a "deep pot" magnet. It needs to be Alnico or Samarium-Cobalt, these do not demagnetize with the heat. The Alnico type are cheaper. So thats what I used. I got it on Ebay.
The silver target is clamped on to the bottom of the magnet by a little ring. When I turn the salad bowl over in the video, you can see the silver disk facing the camera.
I drilled a 6mm hole in the bottom of the salad bowl to hold the magnetron. Its sealed with an o-ring.
The bowl is being evacuated from below the little aluminium "table" in the video. It just blocks the view of where the outlet is!

Oh and don't mind the vacuum gauge, I was just using it as a visual guide for when I had reached the maximum vacuum of my pump/set up. The sensor to read the vacuum level is home made and not the correct one for that meter.

Let me know what bit you are interested in and I'll put up more detailed posts.