have the semblance of the beast. Ye gods. My fingers are numb from
screwing in a thousand (or so) 12 point screws. Not to mention removing
the vacuum tight seals from all the flanges and such. I can barely type
because my fingers have no feeling. Oh well, it was worth it. The
picture on the left is the beast as it
looks mostly assembled. Click on the picture for a larger view.
I was hoping to have vacuum tested the system, but it was not to be.
Several things went wrong. First rule is always read the fine print.
The six inch flange has through bolt holes, rather than threaded. It’s
exactly as I specified, but I had forgotten. <sigh> So I’ll have to
get a bolt set for that flange (it’s covered with the orange plastic in the
picture) tomorrow. Second rule is to measure the flange, don’t just
estimate it. I thought the main flange for the hemispheres was 14".
Nope. 14.5". So the viton gasket I got for that flange just doesn’t
work. Have to (hopefully) return this tomorrow and pray they have a 14.5"
viton seal. Third rule is that not everyone thinks bolt holes are the same
size. The main flange which connects the chamber to the TOPS has smaller
bolt holes than the bell jar base which came with the TOPS. Gee.
Have to get a bolt set for that as well.
So all that delayed the actual testing of the beast for tonight. It was
fun though, putting it together. Wish I had actually built the chamber
itself, but gee – I’m just not that good of a TIG welder at all – certainly not
vacuum quality. Nor do I have a machine shop capable of building the beast
to even a semblance of the tolerances that Huntington did. I went down to
Huntington and got a tour of the place from Herb – the gentleman who managed my
the building of my chamber. Ye gods. 100,000 square feet of
amazingly cool machinery. Huge and really cool computerized milling
machines that made me physically drool. Racks and racks of seriously cool
raw material just waiting to become pieces of high quality chambers.
Amazing. If heaven actually exists, it will be much like Huntington for
I decided to use viton gaskets on all the conflats. Yea, I know.
What’s the use of conflat seals if you aren’t using metal gaskets? Well,
the problem with metal gaskets is their very high price. Copper is not
cheap. Oxygen free and precision punched. Not exactly free.
And once used, it’s a false economy to reuse them – ever. However, knowing
this, the vacuum industry makes viton gaskets for conflat fittings.
Duniway pre-outgasses these gaskets, and claims they have an outgassing pressure
of 10-10 torr. Yow. If this holds
true, then I’m going to be one happy camper. These gaskets are reusable –
unlike the metal gaskets. And since I think that 10-7
will likely be sufficient for my needs, I think that this will work out so very
well. If these gaskets perform as Duniway advertised, then 10-9
is not out of the question. Gee, wouldn’t that be just ducky?
Naturally, there’s something wrong here. Has to be. Otherwise, why
would anyone be using metal gaskets at all? No doubt the hammer of reality
will come down and let me know how things really work. But until then,
I’ll satisfy myself wrapped in the illusion that 10-7
is going to work for my experiments. Knowing all along that I’m just
living in fantasy land… And if the viton gaskets don’t get me low
enough, I can always switch to copper gaskets. But by then, I’m sure to
have made ample use of the reusable viton gaskets in my exploration.
Anyways, until tomorrow…