Homemade X-Ray Machine: Liftoff

[AutogolazzoJr]

Well, after 5 or so months of posting odd questions on the forum, it's finally done.
I got the idea from this:
http://4hv.org/e107_plugins/forum/forum_viewtopic.php?106277.0
I used a Russian 2c2s tube to produce x-rays. For the high voltage, I used dual flyback transformers with two zvs drivers, with secondaries in series and 5+5 primaries, each primary going to its respective zvs driver.
The total generated voltage is around 50kv-70kv. The voltage was able to jump from an alligator clip and a ~20 gauge wire spaced 7.5cm apart. Yes, I was shocked by it. It hurt.
The 50kv was applied to the 2c2s tube in series with a ~.8Mohm resistor. With the power supply turned down to about 25kv, the geiger counter went off like crazy, but their was no illumination of the x-ray phosphor screen. With maximum power (30v through an LTC3780) it dimly lit the phosphor and produced hard x-rays (penetrated aluminum foil).
Sadly, both 2c2s tubes burnt out and the ltc3780 module was fried. I hope to be doing more work on this project. I have ordered 2 more 2c2s tubes and an american 2x2a.

UPDATE 6/10/20: It's been quite a while since i've touched this project, but I felt like detailing what I actually did. So, I used two of these for the power supply.

Both of these were fed (in parallel) by one of these boost converters.

I adjusted it to output 30v and as close to 20A as possible.
The flyback transformers were connected in series and the russian 2c2s tube was connected in reverse polarity (anode grounded, and all of the cathode pins connected to hv).

Gallery: https://imgur.com/gallery/BbXQRhR

[AutogolazzoJr]

BTW: inverse polarization was used, with the anode grounded and cathode to HV+.
These clips are blurry, but I swear that the image on the phosphor was sharp.


https://www.youtube.com/watch?v=QtNm9qtkJQ4&feature=youtu.be

[KE5FX]

Keep up the good work, and don't be this guy.

I'm sure you know to be cautious when using a Geiger counter to check for the presence of X-rays, since the tube can saturate.  But for the benefit of those following along at home: if the counter ever goes completely quiet, it means that either your HV supply has broken down, or that your DNA is in the process of doing so. 

[AutogolazzoJr]

I've heard of him. I hope my fate isn't the same as his. From now on, all tests will be behind lead or remote.

[AutogolazzoJr]

https://www.ebay.com/itm/DC-DC-Converter-10-12-15-20A-150-250-300-400-1200W-Step-up-Step-down-Buck-Boost/382219150784?_trkparms=pageci%3A712b3957-27fc-11e8-8f5d-74dbd180804a%7Cparentrq%3A2796433f1620a861f027772afff92151%7Ciid%3A1&_trksid=p2481888.c100675.m4236
Is this a good replacement for the ltc power supply? Does it really supply that many amps?

[james_s]

It's fun to experiment with various tubes, but if you just want to take nice xray images you can buy complete dental xray heads on ebay. The older iron transformer type are fairly easy to drive, and the heads are well shielded so they are a lot safer than a bare tube. Either way be extremely careful, xrays are no joke, you can easily cause real harm to yourself or others and get in a lot of trouble from the authorities.

[Bud]

A mix of the topic Subject and your age scares hell out of me. I am hoping you understand what you are doing.

[Cyberdragon]

https://www.ebay.com/itm/DC-DC-Converter-10-12-15-20A-150-250-300-400-1200W-Step-up-Step-down-Buck-Boost/382219150784?_trkparms=pageci%3A712b3957-27fc-11e8-8f5d-74dbd180804a%7Cparentrq%3A2796433f1620a861f027772afff92151%7Ciid%3A1&_trksid=p2481888.c100675.m4236
Is this a good replacement for the ltc power supply? Does it really supply that many amps?

Beware! It says the internal heatsinks are not good enough for the max current (for all of them), so you'll need fans.

You don't need two flybacks, you can use a diode-capacitor multiplier. You can also use spark gaps (Marx generator). The current limit for the tube might also need to be higher, try several megs. You could also have a current regulated supply (and also thermal cutouts) for the driver transistors if you want to go fancy.

http://uzzors2k.4hv.org/index.php?page=tubexray

P.S. Speaking of Ebay X-ray machines...how much are you willing to spend? Because this is an absolute bargain (and would be a lot safer).

https://www.ebay.com/itm/Belmont-Dental-X-ray-Head-Model-065-Type-BE-WK-with-Beam-Limiting-Device-/273071198127?_trksid=p2385738.m4383.l4275.c10

It says "tested working" So I assume it has a working tube already in it. Runs on 65KV at 10mA.

[AutogolazzoJr]

Thanks! I can rig up a fan to cool it off. I only turn the thing on for a few seconds at a time, anyway.
The dual flyback system seems to be working fine. It can put out tons of current and voltage without arcing over internally. A cw multiplier is not an option because the flybacks have internal diodes. I will be using more current limiting in the future.

That x-ray tube belongs to someone who doesn't care about getting in trouble with the Feds and has a little less life to live. Quite a bargain though.

[Teledog]

There's some info on DIY X-ray machines in the 1960's Scientific American "The Amateur Scientist" book.
Had a used dental X-ray machine in the garage..gave it away (used to work for a med supply co)
I might suggest using old school "intensification screens"..they light up & you'll need substantially less power/time to expose film/see an image
Dentists "are supposed" to replace their panoramic intensification screens every few years..maybe ask yours for old ones (assuming they haven't gone digital/CCD ..as a lot do now)
I'm old & don't care anymore....BUT, if you're young,.. I'd suggest a lead apron when playing.

Edit: X-ray heads typically run for less than a second - between 2-3 minute cooling periods, depending.
The HV transformers are typically in the head and submersed in oil
If there's oil pissing out of a dental X-ray head..it's been over-run/overheated & toast!
Don't ever expect the X-ray to run longer than 3/4-1 second every few minutes,

[AutogolazzoJr]

 My phosphor screen is 3m trimax 12, which (I believe) produces sharp images at the cost of dim image. Perhaps this would work better? The only downside is that is is quite expensive from Russia. https://m.ebay.com/sch/i.html?_odkw=x+ray+intensification+screen&_from=R40&_trksid=m4084.l1313&_nkw=x+ray+intensifier

[Cyberdragon]

Modern X-ray machines can take more images than that. When I'm at the dentist they take at least four images in a minute, and that's with a 90s machine. But still only pulses, at some sort of high frequency.

https://hackaday.io/project/3665/logs

[james_s]

It all comes down to anode heat capacity. You can run a tube for much longer periods at low current but if you crank up the kVp or mA then the exposure has to be shorter to avoid overheating the tube. There is also a heat capacity of the whole head, they are filled with either oil or in some cases SF6 which absorbs heat from the anode and dissipates it in the case.

Dental heads are probably one of the safest sources for amateur xrays, they are relatively low power and very well shielded and the HV is self contained. They can still be very dangerous if used carelessly but it's much safer than playing with bare tubes. Xrays are very high energy photons, they can burn your skin very much like intense sunlight, except that they pass through you and burn all the way through, and smash up your DNA in the process. You don't want that!

[AutogolazzoJr]

Some more results of gameboy cartridges:
All 1 second exposure, f2.8, 1st image 3200 iso, 2nd 1600, 3rd & 4th 800.




https://imgur.com/a/JReAx

[Mr. Scram]

What are the other parts we're looking at? Looks like some kind of carpet in a closet.

Other than that, very cool! And like everyone says, be safe! These are very cool experiments, but a false move can be costly. Be mindful of every step you take.

[james_s]

Also be very mindful of what is behind your target. Xrays will go right through the wall and through the neighbor's house. You need to be absolutely certain you aren't exposing anyone to radiation, that can get you in very big trouble.

[David Chamberlain]

Think you just voided the warranty on those cartredges. But yeah very interesting - and yes be safe.

[AutogolazzoJr]

Anyone know where I can find small X-ray tubes for cheap like this one: https://www.youtube.com/watch?v=ADAOFMsQi2U?

[james_s]

That's a dental xray tube, you can get the whole heads on ebay often for under $100. I'm not sure why people take them apart, it's much safer to use the dental head intact as it has all the shielding and insulating oil or SF6.

[Cyberdragon]

Just make sure you get one that's new enough to not have PCBs or anything else too nasty in it.

[james_s]

I wouldn't worry about it, most of the stuff you'll find is 80s or later which is not going to have PCB oil. Even if it's an old one that does, it's not going to hurt anything as long as you leave it alone. The problem with PCBs is that they are extremely stable compounds that don't break down when they get in the ground so they end up in water supplies. It's not particularly dangerous stuff to handle but you don't want it in your food or water so disposal can be an issue.

Whatever the case just don't take the head apart, the oil filled ones are messy, the SF6 (gas) filled ones you'll let the gas out if you open the head. Either way the transformer will flash over if you try to run it in air. Also don't try to run one directly off the line, usually you need about 80V on the primary for full tube voltage and something similar on the filament. If you temporarily remove the aluminum filter from the output you can adjust the filament voltage by eye, it should glow about like a low wattage incandescent lamp, white hot, not the dull orange of most thermionic filaments. This is because an xray filament is pure tungsten.

[AutogolazzoJr]

Is there any way to make the pictures sharper? any new form of imaging? The problem with the tube is that the x-rays diverge at a very wide angle. Prehaps moving the x ray source or thing being imaged a bit, and only having a small part of the object imaged? Kind of like a raster scan? Maybe there is a way to focus the x-rays? Thanks.

[SilverSolder]

To sharpen the image - maybe try making a "pin hole camera" for X-rays?   Place the tube behind a lead plate with a small hole in it?

The idea is to make the X-ray source more like a point source, not a laser beam.

[Wolfram]

You have to figure out where your lack of sharpness comes from. If you use a rectifier as an x-ray source then the x-rays will be coming from a broad area, leading to significant geometric unsharpness. To get the best possible results, place your imaged object as close to the screen as possible, and place the source as far away as practical. A pinhole to reduce the apparent source size as suggested by SilverSolder would also work. Both of these methods will of course also reduce your light yield, so you will be limited by camera noise and overheating of the tube. As suggested by James, a dental x-ray tube will yield superior results, I've attached some sample images taken with a dental x-ray tube on film and cassette screen.

[james_s]

Sharpness is a combination of anode spot size and anode to subject distance. You can't do anything about the spot size as that's part of the tube design but you can move the tube further away. You will gain sharpness at the expense of needing longer exposure times.

There are other factors too, the grain of the phosphor screen, mammo screens have finer grain but they require longer exposures or more power. If you are imaging the screen with a camera that could be your limiting factor too.

[technix]

Somehow I feel you should be buying lead-loaded protection gear or put the whole thing in a cellar.

[AutogolazzoJr]

The machine is not in working order right now. I need to get more tubes from my russian seller. When I run the x-ray machine, I am nowhere near it. It's all done remote.

[james_s]

Why do you need more tubes? Did you blow up the one you had? It should only take one tube.

[Wolfram]

As far as I understand, he's (ab)using high voltage rectifier tubes to generate x-rays in cold cathode mode by overvoltage. They usually don't last very long and they don't have a well defined focal spot, making it difficult to take sharp x-rays with them. These tubes are pretty cheap to start with, but they don't last very long, so it usually makes more economic sense to get a dental x-ray tube to start with if you plan on taking more than a couple of x-rays. The only case where it makes sense to do this if you want to make a point out of generating x-rays without a purpose-designed x-ray tube.

[AutogolazzoJr]

I don't really have access to dental x-ray heads. My mission is part proof of concept, but I'd like to get some good images out of it while still staying safe. I have some better pictures:

[Wolfram]

Those are pretty good pictures for such a setup. The broad focal spot gives the images an interesting look, maybe that could even be used to artistic effect, if your intention is making interesting-looking images.

If you at some point want to get a purpose-made x-ray tube, note that x-ray heads can often be had for less than equivalent x-ray tubes on eBay. Another bonus is that they come with a nice power supply included, either an iron core transformer or a high frequency transformer + multiplier setup.

[AutogolazzoJr]

Thanks! As for james_s, the 5 tubes that I used have all either lost vacuum or no longer produce bright images. They don't last very long. A long cool down time should help.

[james_s]

Oh, yeah forget trying to use rectifier tubes to make xrays, why bother? I've bought complete dental xray heads for less than $100 before, you could easily spend that much killing other kinds of tubes and you'll get FAR better performance from the real deal. In addition if you buy a complete head you'll have something that is much more convenient to use and more importantly, much safer.

https://www.ebay.com/itm/Gendex-x-ray-head/113322808953

https://www.ebay.com/itm/Gendex-GX-900-Tube-Head-only-Dental-X-Ray-ge-INTRAORAL/372482456855

https://www.ebay.com/itm/MarksMan-I-SS-White-dental-X-ray-head-medical-xray/223205413866

[AutogolazzoJr]

Here is the imgur: https://imgur.com/gallery/BbXQRhR

[Gyro]

You really used it on human flesh?  That rather implies that the rest of you was in the close vicinity too.

EDIT: Looking back to the OP, I see you are only 15. It might be time to grow up if you want to make it to16 - seriously, take it from those of us who know, cancer is no fun.

[EEVblog]

Here is the imgur: https://imgur.com/gallery/BbXQRhR

Please DO NOT use this xray machine on yourself, this can be SERIOUSLY DANGEROUS to your long term health.

We applaud a 15yo building their own xray machine, but we are deeply concerned for your safety.
The fact that your xrayed your own hand shows how little you are taking safety seriously.

[Gyro]

You see all those bright pixel dots on the images of your hand and foot - and particularly on the closeup photo of the tube, those are strikes by soft x-rays and other particles.

A medical X-ray head has a Aluminium (or other metal) filter to get rid of these, leaving only the hard X-rays. Soft X-Rays from a 'dirty' source are absolutely the worst as they are absorbed by flesh rather than passing straight through. You took quite a high dose of them there.

[InductorbackEMF]

As neat as it is to see please do not try xraying your self again.
Try chicken bones or something else. 
(Oh and i would frame the picture of your hand on a wall)


Alex.

[AutogolazzoJr]

It was a bad idea. However, I later realized how bad of an idea it was, so I stopped doing it. I told you that everything was done remotely. That wasn't (obviously). I used lead protection on the rest of my body, and I believe it was a safe dose (EDIT: it's not. Soft x-rays). As I said, I no longer do it. Thanks to all of you whom are concerned with me. I don't use the x-ray machine anymore, but I might soon. For all the pictures taken after the flesh ones, I completely left the room.

[AutogolazzoJr]

Here is the imgur: https://imgur.com/gallery/BbXQRhR

Please DO NOT use this xray machine on yourself, this can be SERIOUSLY DANGEROUS to your long term health.

We applaud a 15yo building their own xray machine, but we are deeply concerned for your safety.
The fact that your xrayed your own hand shows how little you are taking safety seriously.

I do and did take safety seriously. The exposure lasted one second. I used a Geiger counter to make sure I wasn't receiving too much of a dose. I used lead to shield the rest of the room and my body. More info above, and thank you for concerning my safety.
As a teenager, I lack judgement. I obviously need to be taking this more seriously, which I did after I took those pictures. If I actually revive this project, I will take even more safety measures to make sure nobody gets injured.

[Gyro]

Your response to the safety feedback does you credit, many teenagers wouldn't have been so mature about it. You've obviously had a fright, but have hopefully done yourself no damage. Pausing the project at this stage is probably a good thing - it will give you time to get a pencil and paper out and start thinking about how you can improve the setup, both from the safety perspective and for achieving a better point-source for focus... and protecting your camera too (those pixel speckles were rather impressive!). Maybe a better source will turn up too.

It's probably also a good time to do some research on the history of X-rays, and the early pioneers rather than just current implementation. It's a fascinating reading about the early set ups and the mistakes they made. I remember seeing the images of one early radiographer in a London hospital who actually documented the crumbling of the bones in his hand over many relatively uncontrolled exposures. It's believed now that Marie Curie, after all the risky stuff that she did isolating Radium and Polonium, may well have died, age 66, as a result of the X-ray exposure from the work she did running an X-ray machine in the field during the first world war. As I say, there's a lot of interesting reading to be found on the web.

I'm not sure how your metalworking skills are, but you could maybe look at mounting the tube in an offcut of cast iron or steel pipe with a window cut in it, you could then experiment a bit more easily with plates with different apertures to try to improve focus. You'd probably need the Lead too, but it might help to constrain things a bit better.

There are also members on this forum with professional X-ray experience, Fraser comes immediately to mind but I'm pretty sure there are others.  They may be able to offer you practical and safety advice too. Do some forum thread searches.


I really hope none of the above comes across as condescending, as Dave said, it's seriously impressive that someone of your age can come up with anything of that sort of power, PSU included. I have a Hitachi Kenotron tube, which a few seconds experiment with 25kV (forward direction) and a geiger counter was enough to scare me. At 45 years older than you, I haven't plucked up the courage to take it any further yet, because I don't really trust myself not to cut corners on safety!

[james_s]

Seriously, just use a proper xray head, or don't play with this stuff at all. Taking an xray of one's hand with an un-shielded rectifier tube means a significant dose to the rest of the body, even if you try to protect it it's very hard to protect everything. There tends to be a lot of safety hysteria in the world these days but this is one of those cases where the concern is justified. Xray photons pass through your body, blasting apart your DNA. It's a bit like UV exposure from the sun except it penetrates all the way down through your tissue and bones. As has been mentioned, the soft xrays are particularly dangerous, a real xray head has an aluminum filter to block those.

[Treehouseman]

I'm going to put in another vote for just getting a dental xray head, they're easy to use and they're a good known level to work with. Though I will also note that the entire "the xray head will filter those soft xrays" thing is a bit inaccurate, I still get hot pixels on my camera when using the xray head even if it's not in the path of the beam. Granted I don't know what exactly he's running at and what his camera settings are, but they do still happen. This isn't to say that running that tube without shielding isn't insanely stupid, but a sheet of aluminum doesn't stop those stray xrays.

[BFX]

From the photos what I seen I'm almost sure you have to stop your experiments right now for a long time!!! 
This is not dangerous only for you but also for your family or neighbors.
And I need to mention that you can finished with your "experiments" in the jail!
Again !!! X-Rays are more dangerous than main voltage! Believe me I'm X-Ray medical machine developer.

[AutogolazzoJr]

I haven't x-rayed anything since may. I have no plans to x-ray anything soon. Thanks for the warning, though.

[PointyOintment]

Those pictures of the fan, with the back side much larger than the front side, show that the beam is very wide. At first I thought that made it more dangerous (to bystanders, neighbours, …), but then realized that that means the beam rapidly gets less intense with distance, which is better for safety. I don't know which effect (more or less dangerous) is more important in this case. Regardless of that, I wouldn't run it when it's aimed in any direction but down into the ground, just to be careful.

[james_s]

I'm going to put in another vote for just getting a dental xray head, they're easy to use and they're a good known level to work with. Though I will also note that the entire "the xray head will filter those soft xrays" thing is a bit inaccurate, I still get hot pixels on my camera when using the xray head even if it's not in the path of the beam. Granted I don't know what exactly he's running at and what his camera settings are, but they do still happen. This isn't to say that running that tube without shielding isn't insanely stupid, but a sheet of aluminum doesn't stop those stray xrays.

High energy xray photons can interfere with the camera too. Also perhaps "attenuate" would be a better word than "stop", the aluminum filter blocks the low energy xrays the way glass blocks UV. It doesn't stop 100% of it but it does greatly reduce the amount that gets through. A dental xray head can still be quite dangerous if one is careless, but it's far safer than an open tube.

Whatever the case, where you need to be paranoid is when you have any chance of exposing other people. Few things get people scared to irrational levels like the word "radiation" and if anyone thinks they might have been exposed, even if the level is far too low to cause any harm, you can end up in a lot of trouble.

[mr_darker]

There's a good guide on making xrays and safety too, on instructables actually, probably the only decent instructable on that site.
https://www.instructables.com/id/How-to-X-Ray/

[SiliconWizard]

Hopefully your next project is not involving plutonium.

Seriously though, however interesting that may be, experimenting with X-Rays as an amateur is probably best avoided.

[tggzzz]

Hopefully your next project is not involving plutonium.

Seriously though, however interesting that may be, experimenting with X-Rays as an amateur is probably best avoided.

As my 1930s book "The Boy Electrician" notes, if your skin turns red you are probably using it too much.

[james_s]

Lots of people experiment with xrays, it can be a very rewarding hobby. The key is to do so carefully and safely, never exposing yourself or others.

[cdev]

If you are doing this thinking it will give you an edge getting into a better college, keep in mind that college admissions counselors get lots of applications from creative people and a top worry in colleges these days is people who endanger others safety.

If I were you I would wait on this particular experiment until you are older and can afford at least a lead lined case as is used in professional x-ray machines for materials science.

Frankly, I am surprised that what you are doing is legal. Everybody is a little bit reckless at your age but keep in mind that radiation can actually damage your brain.

To be a bit more specific, all cells have a finite number of divisions in them, (the so-called Hayflick Limit) and radiation can use up that repair capacity inherent in your cells before their time.

Despite what you read, there is no safe level of radiation, because of its quantum nature, it all damages cells, the only question is how many get damaged.

If I were you I would pursue some other, safer line of scientific inquiry.

[james_s]

It's not legal, but neither are a lot of other fun things people do.

[SiliconWizard]

Hopefully your next project is not involving plutonium.

Seriously though, however interesting that may be, experimenting with X-Rays as an amateur is probably best avoided.

As my 1930s book "The Boy Electrician" notes, if your skin turns red you are probably using it too much.

 

I actually just got ahold of a PDF copy of this book out of curiosity. This thing is a goldmine historically speaking. I love it. Makes you dive right into the 30's.
They have a chapter about X-Ray experiments and at one point they suggest putting your hand at least 15 minutes straight under the X-Ray tube in order to get a good picture.

You have to place this book in its context. This was also a time were radioactive cosmetics was a thing: http://www.cosmeticsandskin.com/aba/glowing-complexion.php

Seriously though, for the youngsters (and older ones), that's not safe.

[Neukyhm]

they suggest putting your hand at least 15 minutes straight under the X-Ray tube in order to get a good picture.

I Imagine what they would say about a CT scan if they had it:
"We need more than 1000 images from different angles to get a good and noise free scan, at 15 minute per shot, you will have to be in the machine without moving for 10 days being irradiated."  LOL.

[cdev]

We have to stop raising people to be so trusting of technology just because its 'new'. There is so much technology thats actually quite unhealthy that we have around us for one reason or another, that its a ticking time bomb as far as health goes. In particular I am thinking about endocrine disrupting chemicals (of which there are a great many used for common things like food packaging, flame retardants in furniture and on carpets, and non-stick/stain resistant coatings on cookware and rugs/clothing. Also in wiring insulation.) These chemicals are making people morbidly obese and giving people predispositions to get metabolic syndrome and diabetes, as well as reproductive cancers in a dose-related manner.

They change the body's energy set points. This impact isn't just on the person who is exposed to them. By some mechanism thats not understood at all, this set of problems also impacts their offspring.