Cheap grease

Look, its non silicone high vacuum grease that doesn't cost alot like Apiezon does! I got this over the phone from a lab suppliers in the UK.

Water Cooled Magnetron. A go go.

I decided to try a water cooled magnetron. My Oil Burner Ignition Transformer is rated 8000v at 34mA so thats.....8, 3s are 24.... 250watts or so. Enough to get hot in a vacuum I would think. So I made an inner brass cylinder to fit around my deep pot magnet from .5mm sheet and silver soldered it. I then made two rings of 4mm dia wire, these fit over the inner cylinder. Then an outer cylinder, brass silver soldered. I then soldered it together. The lovely copper pipe to get the water in, came from Halfords. I'm not sure why they sell it but I suspect something on the break line of cars.
So I flared the ends and drilled 4mm holes in the sleeve and soldered the pipe in place. Fingers crossed its water tight...



The seal around the inlets on the belljar is just an o-ring Wilson Seal style. Its a standard plumbing fitting altered a bit on the lathe. It is necessary to remove the first 3mm or so of thread on the 'body' of the fitting in order to allow the 'nut' to pinch the o-ring enough. I also recut the inner bevel of the body of the fitting to 45 degrees or so. It seems to work well. Plus grease of course.

The anode here is a similar setup. The loop is iron wire, well no, its a welding rod so it's probably steel !

Bell Jars, a rural approach!

I have been working on my new set up for a while now. I've been a bit busy on other projects but I'm gonna try detail some of the bits I've finished.
The first thing is the bell jar. Its made from a 'recorder jar' from a milking parlor.(Thanks again to Mr Hart!) I picked three up at local farmers auction. Cheap too!
As far as I know they were used to keep track of how much milk was being sucked out of the poor cows. We like them because they are made for vacuum use.
This is how they look in their original state. Closed at the top and bottom. An amazing piece of glass.


I went to Ireland's only scientific glass blower(details below) and got him to cut the bottom off one. It was borosilicate, the others seem to be nonpyrex glass. I'm not sure what they are made of.
The good news was that the boroglass one had two openings at the top. Perfect for the sputtering setup I was hoping for. I wanted to isolate the baseplate from the sputtering power supply.(Note: the pump and therefore the baseplate is earthed and that is the same potential as the magnetron, so this makes it not really isolated from the sputtering power supply. I don't know what else to do!)
I believe finger prints can be an issue in high vacuum, I wonder if foot prints are an issue too?!

The name of the scientific glass blowing company is Lab Glass Services. They are in The Grange, Oldtown, North County Dublin. Talk to Colm a very helpful chap! 01 8433442

BL Neon!

I was lucky enough to visit a fantastic neon sign company this week. Bernard, the owner of the company BLneon was kind enough to give me an in depth and fascinating lesson in many aspects of neon work.

Below is a picture of a piece of neon he made for me there and then as he explained the process of how a neon sign is made.
My first contact with BLneon was a cold call a couple of weeks ago. I was looking for a used 15kv NST as a laser power supply. (I'm trying to eliminate possible problems with my currently non-functional laser.)
I explained what I was up to and Bernard was bemused but interested in what I was badly describing over the phone. Without hesitation he offered me a visit his workshop in Celbridge and I jumped at the chance!
This is a shaky shot of Bernard and his son Keith with the freshly made neon tube!

Visit BLneons Website: www.blneonsigns.ie

Ciaran looks after the digital end so don't forget they do normal signs too!

I was very touched by the generosity and openness of the whole family on my visit. Unfortunately a lot of companies in Ireland have become very paranoid and secretive over the last while, fearing I assume litigation or thievery from everyone who isn't a straightforward customer.
My visit to BLneon rekindled my faith in Irish companies. Perhaps when the focus is on quality and craftsmanship instead of money, there is far less to fear.

Many thanks to Bernard, Keith and Ciaran!

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:

http://stores.ebay.com/Orcon-Technology

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.

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.