What is next for the 8" cyclotron?

For the design and construction details of ion guns, necessary for more advanced designs and lower vacuums.
Post Reply
User avatar
Noah C Hoppis
Posts: 56
Joined: Sat Dec 22, 2012 4:05 pm
Real name: Noah C Hoppis

What is next for the 8" cyclotron?

Post by Noah C Hoppis »

Ok I have an entire summer to kill and a newly purchased 9" magnet (no faceplate, that will be fun...). After being warned, "the day you become catholic is not the day you become pope" I have begun to wonder what is next? My vacuum system currently consists of a insufficient fore line pump and a 4" diffusion pump. The whole thing has been CADed and reCADed multiple times. So what should I focus on next? I don't just want to move directly on to milling the chamber and dees yet, more looking towards what is my next major obstacle? Any replies are welcomed and much appreciated!
"No missile ever flew before 10 pm"
User avatar
Rich Feldman
Posts: 1470
Joined: Mon Dec 21, 2009 6:59 pm
Real name: Rich Feldman
Location: Santa Clara County, CA, USA

Re: What is next for the 8" cyclotron?

Post by Rich Feldman »

Hi Noah.
How 'bout:

1) show and tell us about your magnet.

2) make a little "demo fusor", or at least light up some rarefied air in a vacuum chamber of some sort,
and report the internal pressure.
It's hard to believe that the first vacuum chamber you use or make will become part of a working cyclotron.

3) How do you know your forepump is inadequate for your diffusion pump?
As mentioned in a recent thread, you don't need to meet a liters-per-second number if your diffusion pump isn't moving lots of gas. You just need to keep the foreline pressure low enough (100 microns?) for the diffusion pump to do its job.
All models are wrong; some models are useful. -- George Box
User avatar
Chris Bradley
Posts: 2930
Joined: Fri May 02, 2008 7:05 am
Real name:

Re: What is next for the 8" cyclotron?

Post by Chris Bradley »

Noah C Hoppis wrote:So what should I focus on next?
I have no real idea what it is you're trying to tell us in this post, nor what the question really is. I suspect you don't, either!

So I think the best answer to this question would be 'clarity'!

I sympathise. I'm sure I am not alone in confirming that you may well get to points in your project where you have so many 'threads' of activity that need to be tied off that you don't really know where to start, particularly if you are going down a novel route no-one has provided a 'recipe' for. Been there. A sort of 'experimenter's block', so to speak. I've wasted days-worth of time pontificating over what really needs to be done next, and being torn in many different directions that it causes me to 'stall'.

The earlier you are in a project the worse it usually is, because there are so many 'possibilities' that you end up thinking you need to do 'A' before you can possibly decide on 'B', yet you also need to do 'B' before you can do 'A'. Stall!

Ultimately, only you can decide what priority next makes sense. If nothing makes sense to do next, just do something! If something needs to be done, just get on and do that, and at least it is 'progress'. You may find you ended up doing things you didn't need to do, but it'd be surprising if that never happened! Eventually you'll have whittled down all the ancillary jobs that it is then made clear what the next steps are.
User avatar
Noah C Hoppis
Posts: 56
Joined: Sat Dec 22, 2012 4:05 pm
Real name: Noah C Hoppis

Re: What is next for the 8" cyclotron?

Post by Noah C Hoppis »

Ok addressing the magnet:
It has 8.75" pole faces, a 16" x 4" cross section for the yoke, C shaped vs the classic double E shaped, 2 coils that are 16" x 4" x 4", and the whole assembly is 20" x 18" x 16"
Addressing the foreline pump:
It is a one stage claiming to pull ~37.5 microns of Hg at 1.4 LpM though it is only the size of a large shoebox with and has a 1/4" output.
Addressing the vacuum chamber:
I don't have enough parts to even assemble a closed shape yet :(
well; kinda.
I'm looking for what subsystem is the next thing I should focus on, because the magnet was an easy first choice, you need to know exactly what magnet you have to design everything else, beyond that i have no idea what is the next logical thing to start reading up on.
"No missile ever flew before 10 pm"
Post Reply

Return to “Ion Gun Design and Construction (& FAQs)”