Spinthariscope

EEYORE, Fri Aug 11 2006, 07:56PM

Hello all,
I am in the process of building a spinthariscope. I am almost done, but need some tips...
I got a bottle of Silver Activated Zinc Sulfide powder. I need to figure a way to make a screen with some, without wasting much as it was $$$$$$$ at 25$ for 5 grams!

Here is what I tried last night. I took a plastic coke bottle cap, and poured some 5 min epoxy in there. I then sprinkled the powder over it, but to my horror, the powder began "dissolving?" into the epoxy, thus making it USELESS as alpha particles cannot penetrate the epoxy to excite the phosphor. DAMN! That was about 1/3 the bottle!What a waste...So then i tried letting the epoxy almost harden, but still no luck. MORE LOST PHOSPHOR! angry

So what should i do?This powder is so fine it just dissapears!My next idea is a spray on adhesive from an aerosol can. Seems i need an ULTRA thin layer of adhesive to hold the phosphor.

Once that is done, I will be just waiting on a nice PLOSSL 30mm focal lenght 1.25in eyepiece. I want a wide field of view, and dont need super high magnification. I figure that 30mm focal lenght should be about 10x magnification anyways. Plus, coated optics and all should make for noce viewing pleasure.

I plan to use some Autunite powder for the alphas...Ive tried it, and it works really good! Ive also got some americium 241, but it seems to be lotsa "little guys" rather than a group of "big guys" kinda thing.

Matt
Re: Spinthariscope
Avalanche, Fri Aug 11 2006, 08:04PM

Sprinkle some of the power over some sellotape, or transparent sticky back plastic (like the stuff used to cover books) and run it in. That should work quite well, and you'll get a perfectly even covering.
Re: Spinthariscope
EEYORE, Fri Aug 11 2006, 09:14PM

Avalanche wrote ...

Sprinkle some of the power over some sellotape, or transparent sticky back plastic (like the stuff used to cover books) and run it in. That should work quite well, and you'll get a perfectly even covering.

Excelent idea, i was just considering it too...I can do that, plus put a few small pieces of autunite crystal on top of the coating,and then put down tape over that to seal it all together. That way, alpha hits the phosphor, while prventing anything from coming loose(and thus becoming dangerous). I have measured the gamma output of a few small pieces of autunite, and once inside a container, is next to nill...So all will be safe!
Thanks!
Pics coming..
Matt
Re: Spinthariscope
King_of_Junk, Sun Aug 20 2006, 09:06PM

You didn't get good results with the americium? That would've been my first choice...

Yeah, scotch tape, spellotape, watever should work.

You might try some other elements too. They used to sell thorium lantern mantles, and I know there's cesium in some newer clocks. Hmm... there's always the old radium clock dials you could look for- now that would be something.

That is, if you have the patience. I've never tried to make one, but I know that it might become a major pain.
Re: Spinthariscope
EEYORE, Sun Aug 20 2006, 11:40PM

Americium 241 works...Its just highly active, yet not very energetic...

Im now using autunite "dust"...Autunite is powdery and kinda falls apart, so i put some in with it. VERY great results!

I am done with this project, still waiting for GF to come home with her camera. Nice looking too! Wait for this pics! Ive had great success with this now, and have made several radioactive screens(with my ZnS:Ag + uraninite/autunite/thorianite) that will flouresce in darkness as well...They are so succesful, that I may try selling a few. All that is needed is an eyeball and a lens. They are small laminated screens that consist of a ZnS:Ag screen with radioactive samples embeded in, all sealed up for duribility and safety.
If people are interested, PM me and I will see what I can afford to sell them for(Proably around 10$ depending on what kind of deals I can get on autunite, which is getting $$$).
Stay tuned!
Matt
Re: Spinthariscope
Tesladownunder, Thu Aug 24 2006, 03:55AM

I don't like your chances of getting a picture. The light levels are very low.
The previous spinthariscope threads are here and here

Peter
Re: Spinthariscope
EEYORE, Thu Aug 24 2006, 04:03AM

Tesladownunder wrote ...

I don't like your chances of getting a picture. The light levels are very low.
The previous spinthariscope threads are here and here

Peter

I mean of the spinthariscope itself, not the actual scintillations...I will experiement with getting a snapshot of them in a little while. Mine are actually quite bright, or at least SEEM bright. Perhaps the pain in my eye is from something else? cry My gieger counter barely flinches next to the screen...

Matt
Re: Spinthariscope
Conundrum, Sat Aug 26 2006, 12:16PM

Hmm. you could try letting the epoxy almost dry and then sprinkle powder on.

-A