Building a magnetron first attempt

This is my first attempt at building a diy
homemade magnetron. Next video it hopefully will work, so I can try out a bunch of stuff.

[@SignalDitch]

Excellent work as always! Pinch seals haven't given me that much trouble, but I wonder if that's because I use much smaller wire in the seal. It may be that everything heats and cools more evenly when there's relatively little mass of tungsten, so that when you use thicker wire, you really need to concentrate heat on one wire to make a good seal... It could also have to do with the composition of the wire, all of us hobbyists are getting wire from different sources with no way to independently verify their composition. Also, I'm excited to see how your cathode coating experiments proceed. I believe the most common binders for that application are methyl methacrylate or nitrocellulose. I have a bottle of commercial cathode coating material that has settled into a hard puck in the bottle that I'm working on re-suspending so I can also try building coated cathodes. I don't know how easy it is for you to order things from NA but "electrontubestore" sells thoriated tungsten wire and I've been considering buying a small length of that (about 30cm for 30USD) to play with as well. I'm trying to build a VFD, so I need a lot of emission without the filament being so bright that you can't see the phosphor glowing behind it. Anyway, I look forward to the next video, keep it up 👍

[@thesciencefurry]

@@SignalDitch It could very well be the the thickness of the wire. If I use a long piece I notice that the tungsten just conducts too much heat away so fast. Maybe I try it with thinner wire but shorter. (I always used the thicker stuff for current handling) I tried making nitrocellulose myself but it just dissolves if you leave it too long. I might just buy it. But rn I want to test if I could sinter the yttrium oxide on there somehow. With the benefit that you potentially coat it multiple times with the oxide not reacting with moisture and it hopefully has more adhesion.The work function is slightly higher tho. Also it doesn't solve the problem that the coating is uneven so you might need to work with a binder there anyway. I'm definitely gonna check out the seller for the thoriated tungsten. I think so far I just found overpriced stuff from VWR for example xP I've read, with the right coating the filament has to glow just very slightly, so I'm sure you can get this to work😃

[@friskydingo5370]

​@thesciencefurry sputtering would give you the results you're looking for when it comes to the multiple coatings. 😊

[@jdflyback]

Hi! great looking tubes. I am excited to see another magnetron. I always wanted to make one but did not have the right magnets.

[@MrMarsMink]

Gidday mate, great work..... Many years ago I attempted some vacuum tubes, the seals are a problem of course, theres Kovar and various glasses with multiple layers to adjust the expansion coefficients, Titanium works with some glasses, if my memory is correct. "Quartz," the main point of my comment, is that Tungsten wire is often produced by powder metallurgy, ie tungsten powder is packed inside a steel cylinder and sintered, then it is drawn via many dies to a long wire, this leaves the possibility for very long voids in the wire, microscopic of course, but sufficient to allow some gases to penetrate through the metal. Take a look at the metal seals in linear halogen lamps, theres a piece of thin ribbon welded in between the conductors as a vacuum seal. Check out the expansion coefficients of the glasses vs the metals youre using & avoid tungsten at the seal.

[@TwitchyStuff]

Tungsten should have a nice copper-brown-orange color when it properly bonds to the glass. Silver also makes a strong glass bond... I wonder if one could electroplate or sputter sliver onto tungsten. Also check out housekeeper seals... A little more work to pull off, but looks like the best way to get good glass bonds.

[@zyeborm]

Hey mate looking good there! Love your work! You can see your skills improving with every creation. 2 small things, if it didn't work I'd still love to hear how/why it didn't work? Also your English is excellent, but just for reference in ceramic the first c is pronounced with the soft c sound (basically an s). Doesn't matter at all to the video, you just seemed like someone who would like to know. Otherwise flawless, much better than my German lol.

[@thesciencefurry]

Yeah in german It's "Keramik" and you say it with a hard k. So there that xD Unfortunately I can't tell where it's leaking unless I have a helium leak detector, which is too expensive for me.

[@WariceHimSelf]

Hello, great work thus far, I’m excited to see where this goes. I’ve been fascinated with vacuum tubes and the manufacturing process for awhile and want to get into it but unfortunately tungsten is very expensive. Where do you purchase it? Currently my only source of tungsten is incandescent bulbs. Thank you for reading & keep up the good work

[@thesciencefurry]

@@WariceHimSelf I get it from ebay. Yeah unfortunately it is. Spend something like 60€ mostly on tungsten. But only because I got 20 meters I think

[@FurryAnimator]

i love ur video! ❤❤❤❤

[@SodiumInteresting]

Nice

[@slyfoxchemistry]

Hey nice work well done how are you doing

[@thesciencefurry]

@@slyfoxchemistry pretty good, finally getting more productive in terms of youtube again x3 and you?

[@slyfoxchemistry]

@@thesciencefurry I am good just looking for some tests to run in my lab to put on my channel

[@rafa_br34]

Very interesting.

[@Emmanuel99966]

in the next version it will be a good idea to add a waveguide do direct all the microwaves that are being lost.I would like to know what kind of power supply you are going to use : )

[@thesciencefurry]

@@Emmanuel99966 I think rn I just have a flyback transformer available as power supply. A waveguide may or may not be feasible depending on what frequently I'm at.

[@user-tr4oz9cj6p]

You can do what 🍭 maker does with sugar.

[@SodiumInteresting]

Who