Archived - Fusor Update

[Scott Moroch]

Jack and I have been making great progress with our neutron producing fusor. We got some new parts over the past few weeks. We plan to have all our parts by the summer or late spring. I have attached images of some of the parts we got. We got 2 Kurt J. Lesker bellow valves, an MDC vacuum NW 40 viewport, a 1/4" swagelok hose, a 30 inch NW 16 flexible hose, and a helium 3 probe. So far I am waiting for the NW 16 hose and one of the bellow valves to come in the mail.

The bellow valves are NW 16 and NW 25.

Next to buy is the diffusion pump (still searching) and we will be purchasing the high voltage soon

Scott Moroch

[Scott Moroch]

Next valve and kf 16 hose:

[Richard Hull]

Those valve look brand new! Hope you got 'em surplus. I got mine completely bead blasted and rebuilt from Duniway Stockroom for about half price. I think $175.00 each, cant remember exactly....Been a few years.

Richard Hull

[Scott Moroch]

The valves are brand new. I got them off ebay. I got them for a combined total of 300. Seems expensive, however I checked and these valves go new off Kurt J. Lesker's website for about 290 each.

[Richard Hull]

You got a great deal by most any standard. Good vacuum valves are vital to good operation and sealing and are one of the major vacuum expenses that should not be side stepped.

Richard Hull

[Scott Moroch]

The valves are great and I hope they help for pulling a deeper vacuum. More parts to come: hastings thermocouple gauge, diffusion pump, 10 amp variac, and 15kv NST. Ebay is simply the best for buying parts.

[Scott Moroch]

Thermocouple gauge came in the mail today:

Jack also bought the diffusion pump, 20 amp variac, and 15 kv 60 ma neon sign transformer. We purchased a 20 amp variac so in the future we can set two NST's in parallel and run both off the one variac. If anyone is interested in this variac here is the link: http://www.ebay.com/itm/20-AMP-110V-VAR ... 33897a7e77

[Jack Rosky]

The 20 Amp variac arrived in the mail today. I got it for $95 on ebay. Attached below is a picture.

[Jack Rosky]

Today in the mail came a 60ma 15kv neon sign transformer. It has a gfi, so I will have to remove that. I am planing on doubling it with the capacitors and diodes that also came in the mail. Pictures will be attached below.

Capacitors are rated at 8kv dc and .3 uF

Diodes are rated 400ma and 8kv

Like I stated above, NST is 15kv 60ma

[Scott Moroch]

Just got the ASA to KF fitting we will need for our diffusion pump. Got it for 45 dollars brand new off ebay. I will be purchasing the rest of the vacuum connections we need this friday.

[Scott Moroch]

As the fusor reaches its final weeks more parts have come in. Today all of the vacuum connections: reducers and clamps came in the mail. More parts to come thie week: hydrogen regulator, GS-2000-pro from gamma spectacular, swagelok needle and ball valves.

Other specifics about our fusor:

Our high voltage feedthrough will be made by us using a spark plug and a KF 50 blank. We will be borrowing a diffusion pump from Connor Givans. Our deuterium will be purchased from Sigma-Aldrich in a few days. We will being purchasing 10 liters. Our deuterium regulation system will consist of a hydrogen regulator, a swagelook ball valve for quick shut off of deuterium flow, and a swagelok needle valve.

Our vacuum system is a 285 liter per second water cooled oil diffusion pump backed by a 1/3 horse power 5 CFM 2 stage mechanical pump. We also have a Kurt J. Lesker KF 16 Bellows Valve to control our vacuum system. We have a Hastings Thermocouple gauge and controller and will soon be getting an ionization gauge or convectron gauge. Our first run will probably be done with only the thermocouple and then once we get a little more money we will purchase an additional gauge. The current and voltage metering has been purchased as well and will becoming in shortly. We will also be using Hafnium wire for our inner grid.

When the time comes (hopefully within a few weeks) for demo mode we will make a post under this forum to keep everything organized. Same for when we run with deuterium we will keep it under this "Fusor Update" forum.

Scott Moroch

[Jack Rosky]

Picture of the Hydrogen Regulator that came in the mail today.

[Scott Moroch]

Swagelok Ball valve and needle valve for our deuterium regulation system.

Scott Moroch

[Scott Moroch]

The assembly process has begun!! This seems like a simple question however, when do I know when the KF clamps are fully and correctly on? I want to make sure they are installed correctly because I have never used them before.

Also, I apologize that a lot of my pictures are sideways, I do not know why that happens because I do not take them sideways.

Scott Moroch

[prestonbarrows]

For a KF, if you can get the butterfly nut on then it should be fine. They are pretty hard to mess up. If things are not seated right, you can't swing the nut around without completely removing it from the thread and it is pretty obvious that something is wrong.

You don't really have to crank down hard on the clamping nuts either. The force from the vacuum pressure differential will squeeze things together quite well. At ~15 pounds per square inch, there is a pretty substantial force especially with larger fittings. Really, the clamps are more for structural support; keeping things from falling apart when you are not under vacuum, preventing joints from getting torqued apart. You can pump down with KF blanks held on just by suction and no clamps with no real effect on the ultimate pressure.

Doesn't hurt to get them nice and (finger) tight though.

[Jack Rosky]

Another package came in the mail today.

I got an ammeter and a voltmeter for measuring the volts and amps going into the NST. (Pictures attached below)

Also, I received a gamma spectacular, the gs-2000 pro (much thanks to Steven Sesslemann for his great products). (Picture also attached below)
Sincerely,
Jack Rosky

[Rich Feldman]

Nice set of meters you got there.
Be a shame if you blow them up.

It's unwise to assume that their scaling resistors are built in.
For example, the A and V meter might be identical except for their printed scale cards.

Learn what turns a bare meter movement into a calibrated voltmeter or ammeter.
I would start with very small signals.
Better yet, start by measuring the resistance between the terminals of your meters, in both directions.
The voltmeter should be well above 100,000 ohms and the ammeter well below 1 ohm.
Send me a PM or email if you want more help with AC metering. Do you have a variac yet?

Good luck!

[Scott Moroch]

Jack and I are slowly nearing out test date. We have decided not to go with a spark plug for our feedthrough because it may fail past 20-25kv and potentially harm our power supply. Instead I got a high voltage feedthrough off of ebay (Thank you Andrew Selztman)

In additon, I will post the specifications of our diffusion pump. The next step in our building process is for cleaning in acetone. We will be cleaning all of our fittings in acetone to help reach a deeper vacuum. I have also purchased an ionization gauge controller for the future for a more accurate pressure reading.

In other news, Jack and I have been invited to give a presentation at a local college (New Jersey Institute of Technology) to their physics students about our project. Hopefully NJIT can help us in the future with our fusor as well.

Scott Moroch

[Scott Moroch]

Today Jack and I assembled the chamber for the fusor. We are using swagelok fittings for deuterium regulation. I have a few questions about swagelok fittings for those whi have used them. I bought stainless steel tubing and cut it with a hacksaw and then filed it. However, when I filed it and sanded it, the end of the tubing is at the slightest angle. Does the end tubing have to be perfectly straight? It is a bit hard to explain and I can't seem to get a good picture.

Also, when do I know when the swagelok fittings are completely on? How smoothly should the tubes slide through the fitting? All of them go through very smoothly however one of them gets all of the way in but a little rougher

Sincerely,

Scott Moroch

[Richard Hull]

Swagelock fitting use a ferrule to seal the tubing. As you tighten the fitting, the ferrule crushes the tubing, locking it in place on the ferrule. The norm is to push the tubing about 1/8 to 1/4 inch in beyond the end of the ferrule. The end of the tubing should be smooth and should no protrude into the fusor chamber geometry. This is accomplished by choosing a long enough male stub to weld onto the fusor boby that accepts the tubing end such that it is recessed up inside the stub fitting.

Richard Hull

[Jack Rosky]

The deuterium finally came in today from Sigma Aldrich. Scott and I ordered a 10 Liter lecture bottle.

Picture attached below.

Also an update, a local college invited Scott and I to give a presentation to the physics professors and undergraduate physics majors.

After that, they are cconsidering allowing scott and I to run the fusor there (since both scott and i's parents will not allow it to be ran inside the house).

Tomorrow one of the last fittings for the gas system is coming in from Sigma Aldrich as well.

[Scott Moroch]

We recently recieved the diffusion pump will be borrowing from Connor Givans for our fusor. Special thanks to Connor!! It is a 275 liter per second diffusion pump, which should handle our fusor more than fine. We also recently had our feedthrough TIG welded to a KF 50 blank which is now attached to our fusor.

On a different note: does any one know the whereabouts of Eric Stroud? After searching through the forums I learned there is a fusor in his possession not far from me. Does anyone have his contact information or know if he is still living in New Jersey with his fusor?

Scott Moroch

[Dennis P Brown]

Very nice.
Will the doubler provide enough current (a 60 ma NST doubled will lose a lot of power and will the caps have enough storage capability?) Also, voltage drop off and ripple - will these be issues? Your caps (8 kV) even in series might be a bit low for a doubled 15 kV (p-p voltage might exceed their value.) Did you measure the actual voltage or is this by calculation.

[Jake Wells]

good luck Scott. hope to see you in the high school neutron club.

[Jack Rosky]

Another update:
Today I received the Welch rotary vane backing pump for our fusor. I got it off of eBay for $130. It was $75 with $55 shipping. It weighs around 75 lbs. Pictures are attached below.