I noticed that the fusors that use the hemispheres have a nice polish to them. I now have them here and would like to do the same. I have a buffing wheel for the outside but how is the inner surface polished? Dremel?
New to this forum I have left an introduction. Here is where I am so far with my fusor. The hemispheres are in, the anode grid is made ( stainless) the cathode is made (tantalum) , I have a neutron detector on the way in for my Ludlum counter. Varian has an order for all the conflats required and viewport ,( Similar to Joe's design) The Equipment I have in currently is the rough and High Vac pumps ( both turbo and Ion) The MKS baratrons ( .001 - 10 torr ), RGA, Ion Guages, deuterium ,regulator, leak valve, Vac manifold and a 50 KV 100 ma switching power supply. I have a tig welder and thyratron spot welder but I think I will have a pro machine and weld the fusor. I am constructing to accommodate a 3 grid system and filament.
As soon as I have some parts together I will post some pictures on my web site. Great Forum!
Fusor project under way
Re: Fusor project under way
You certainly came out with both barrels blazing! Having good equipment on hand is a big help, and with all the proffessional parts you are using you should have a killer system. I can't wait to see photos on your website.
As for polishing stainless steel, the outside will look very pretty when polished up, but I wouldn't bother with the inside. It won't help the performance one bit, and after only a few minutes of operation, you will never know that polish was there because the entire inside of your chamber will be coated with a layer material blasted off from the inner grid. The first time you open up the fusor after a run and try to clean this stuff off you will never care about going so far as to polish again. This film is tough stuff, and requires serious elbow grease to remove and harsh chemical agents. With a tantalum inner grid, you will be happy just to keep the viewport clean; the material from tantalum is especially hard to get off, as Richard Hull has noted several times. This layer of deposition gets to be really annoying when working with a bell-jar fusor, since it can eventually muddy your view. Besides, most craftsmen like to keep their work in pristine condition. This can also hinder operation as metal particles get on your insulators and cause electrical leakage. Richard Hull says diluted muriatic acid will remove staining from a stainless steel grid, but I prefer to use Bon Ami powder and alot of elbow grease (obviates need for highly caustic substance).
If you are dead set on polishing the inside, doing it with a rag by hand would be probably be the best way to go, although it would be time consuming. Richard mentioned to me that Joe Zambelli used this method with some auto polish to shine up a piece of scrap stainless that housed his neutron detector.
I'd recommend you goto the the Intranets message archive (link on main page) and read a thread entitled "Chamber Staining" under the Fusor Construction and Operation discussion. There should also be a few posts on this subject back on the Songs archive.
How big of a chamber did you get? I've got a little 6" chamber that I am in the process of slowly machining. Right now my major hold-up is getting an ASA flange and gasket on the cheap to hook my diff pump up with.
I think you have moved faster than anyone else on the list. It also sounds like you're planning to go deeper than most of us have made provisions to do yet.
Good luck, and keep us all posted of your work.
Adam Parker
As for polishing stainless steel, the outside will look very pretty when polished up, but I wouldn't bother with the inside. It won't help the performance one bit, and after only a few minutes of operation, you will never know that polish was there because the entire inside of your chamber will be coated with a layer material blasted off from the inner grid. The first time you open up the fusor after a run and try to clean this stuff off you will never care about going so far as to polish again. This film is tough stuff, and requires serious elbow grease to remove and harsh chemical agents. With a tantalum inner grid, you will be happy just to keep the viewport clean; the material from tantalum is especially hard to get off, as Richard Hull has noted several times. This layer of deposition gets to be really annoying when working with a bell-jar fusor, since it can eventually muddy your view. Besides, most craftsmen like to keep their work in pristine condition. This can also hinder operation as metal particles get on your insulators and cause electrical leakage. Richard Hull says diluted muriatic acid will remove staining from a stainless steel grid, but I prefer to use Bon Ami powder and alot of elbow grease (obviates need for highly caustic substance).
If you are dead set on polishing the inside, doing it with a rag by hand would be probably be the best way to go, although it would be time consuming. Richard mentioned to me that Joe Zambelli used this method with some auto polish to shine up a piece of scrap stainless that housed his neutron detector.
I'd recommend you goto the the Intranets message archive (link on main page) and read a thread entitled "Chamber Staining" under the Fusor Construction and Operation discussion. There should also be a few posts on this subject back on the Songs archive.
How big of a chamber did you get? I've got a little 6" chamber that I am in the process of slowly machining. Right now my major hold-up is getting an ASA flange and gasket on the cheap to hook my diff pump up with.
I think you have moved faster than anyone else on the list. It also sounds like you're planning to go deeper than most of us have made provisions to do yet.
Good luck, and keep us all posted of your work.
Adam Parker
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guest
Re: Fusor project under way
It is great to see others leap in to help out. Adam's polishing advice and pointers to old postings is well taken.
Inside polishing is a fool's errand. (no dis-respect intended). The interior would be better treated by electro polishing, which is not polishing at all, but an electrolytic cleaning of the interior making it more amenable to vacuum work. This is normally done in a citric acid electrolyte with lots of post electrolyizing cleansing heroics. Exterior polishing is great and really enhances the appearance of the system.
If one is bound and determined to polish the inside mechanically, there are a wide range of thick sewn linen pads or disks on shafts designed to go in a standard 1/4" drill in diameters from 2" to 6". Charged with polishing abrasive, these will conform perfectly to the inside of the hemisphere. Auto paint suppliers and better equipped auto parts and refinishing suppliers have them on hand for sale.
We all look forward to those finished images of the fusor in operation. Post a few in the images du jour as you go along with the work.
Richard Hull
Inside polishing is a fool's errand. (no dis-respect intended). The interior would be better treated by electro polishing, which is not polishing at all, but an electrolytic cleaning of the interior making it more amenable to vacuum work. This is normally done in a citric acid electrolyte with lots of post electrolyizing cleansing heroics. Exterior polishing is great and really enhances the appearance of the system.
If one is bound and determined to polish the inside mechanically, there are a wide range of thick sewn linen pads or disks on shafts designed to go in a standard 1/4" drill in diameters from 2" to 6". Charged with polishing abrasive, these will conform perfectly to the inside of the hemisphere. Auto paint suppliers and better equipped auto parts and refinishing suppliers have them on hand for sale.
We all look forward to those finished images of the fusor in operation. Post a few in the images du jour as you go along with the work.
Richard Hull