We are fighting the oxidization of digits | week 18-19/2022

I knew it won't be easy to keep the stainless steel digits oxide-free in close proximity to molten glass. But I didn't expect it will be such a pain. Without breaking this problem, we won't be able to produce the large H nixie tubes reliably...
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[@reps]

maintaining lots of digits is hard work

[@kurtiunlisted8589]

[@ramous5182]

When they are released you should build a comically large multimeter with the H-tube!

[@mvadu]

Says a guy who knows how to keep a voltmeter with 8digit precision accurate..

[@MrMilarepa108]

@@mvadu 8.5

[@zyeborm]

he's got 10 digits man, you need to get on his level ;-)

[@piranha031091]

Hello! Chemist here, I've worked with a lot of air-sensitive systems, so I am familiar with that type of issues. The proposed explanation you give at 16:06, that the purge gas may not displace all the air out, isn't realistic: gas diffusion happens, and it happens fast. As long as purge gas is flowing in your system, the air will get dragged out. Your issue is that the reverse is also true: as soon as the flow of purge gas is stopped, the air will rapidly diffuse back in! The solution is that you need to keep a flow of purge gas in the tube at all times. There is a very simple way to do so without causing an overpressure: inserting a wide enough canula through the rubber plug, and into the glass tube. That way, when the front window seals, the purge gas still has a way out of the tube. And as it keeps circulating in and out through the canula, it keeps removing any air that might have gotten inside the nixie tube before sealing. Hope this helps!

[@AndrewPrice2704]

I had the same idea as piranha -- a slightly smaller hole in the plug than the purge gas feed so the overpressure is small and purge the whole time :)

[@Muonium1]

Also isn't hydrogen going to be the worst for this? Like obviously he's using it because it's a reducing agent but it's the lightest gas and therefore has by far the fastest average molecular velocity at any given temperature than any other gas. Couldn't he just try something heavy like argon or carbon dioxide which will be much slower and diffuse less rapidly even if it's not reducing?

[@borayurt66]

Simple and effective! Best idea so far.

[@glasslinger]

I have another idea but since you said you solved the problem I will hold back until I see what you came up with. I was AMAZED that you could do the feedthrough in that large piece of glass! I have never succeeded at it. Then when it shattered I was not as amazed any more! Same thing happened to me every time! :)

[@Sodabowski]

Even with crossed polarizers to inspect for stress in the glass?

[@AleksServisMan]

Oh, and you are here! I really like to watch your videos and now I often use your crown "OK" in my work. :) Regarding the soldered tube, which cracked: I think it should have been cooled in the oven for a long time to relieve stress.

[@nobodynoone2500]

@@AleksServisMan Yes, annealing glass is important when larger.

[@glasslinger]

@@AleksServisMan The whole point in using boro glass is to remove the awful time consuming process of oven annealing. (and oven reheating to work on the part again!)

[@glasslinger]

@@Sodabowski Yes, the polarizer shows massive stress. You KNOW you are screwed if you try to do anything! :)

[@Rubikorigami]

About the sagging digits, one thing that could help is to do a pizza slice fold : put a slight fold that runs down the center pf the lines of the digits. I don’t know how bad it’d be for the glow discharge’s look, and it might be expensive to manufacture, but it’s a really really good way of preventing flex when done right!

[@cambridgemart2075]

More correctly known as return edge.

[@amarpersaud2950]

Perhaps coat the digits in some kind of flux or oxygen reacting compound that can be dissolved later, and then wash it out using a solvent introduced through the back fill port

[@kitingmare]

My idea to solve this would be a mix of two of yours: Could you feed the purging gas from the back side of the Htube with a sort of long brass tube lance into the front area of the tube (basically mixing the stopper with the tube from 9:15 , just a longer tube, and the last idea of feeding the gas to the front). While also having a hole for the gas to escape in the stopper in the back to prevent over pressure. This way you can have the gas turned on all the time and purge out any oxygen that got into the tube from the flames.

[@jeromevaneersel8491]

that's the trick they used at philips in holland...

[@Splomf]

Something I'd like to add is that, in certain cases, argon is a better gas to use for this application. It is very commonly used with welding and is worth investigating.

[@ophello]

Making the entire design smaller would be smarter. These digits are just too huge.

[@Hyratel]

It's for a client who I presume is paying Very Well for the engineering investment

[@MarionMakarewicz]

You are one patient, determined man. I do love your videos. So focused, calm, and methodical. Good luck!

[@kubeek]

6:10 may be an important point, oxy propane (or oxy - natural gas) flame could be your source of oxidation. To get a proper flame on the torch you need to get the flow of oxygen right, but that does not necessarily mean all the oxygen flow gets burnt in that flame and most likely is entering the hot assmbly. Second, I didnt at this time see when and how you turn off the shield gas entering the assembly, but from the looks of it lenghtening the inlet pipe towards the front glass and providing a larger exit tube back through the base could help you - you would not need to stop the shield gas when the two parts are getting fused together (as you said to prevent the bubbles. the large outflow went would prevent that). 8:10 exactly, positive pressure of the purge gas is gone, but the torches are pushing lots of unburnt oxygen inside the tube. Kdyžtak se můžeme pobavit i česky :) edit 12:10 didn´t expect you could make a hole in the front glass and then seal it later, im curious to see how that one goes :) 13:08 could you chemically de-oxidize the metal after the front seal is made? 14:25 trapped oxygen in the jar plus the heat of the anneal coming from the periphery seems to fit my first note 17:08 same thought as I had in the beginnig, but with your glass skills completely different execution than I imagined 19:50 Come on, you leave us hanging like that? :D

[@davidgustafik7968]

Thanks for another awesome peek into your workshop! Would it be possible to gild the metal segments? It should create a completely inert surface, though at a raised cost of the parts and a yellow surface finish?

[@daliborfarny]

Interesting idea! I think we solved it yesterday, but I will keep gilding in mind!

[@davidgustafik7968]

@@daliborfarny There are other inert materials or at least materials that are more resistant (platinum comes to mind and the more exotic stuff) and are of the right color, but gilding is a well understood process and can be done by any number of companies on an industrial scale.

[@davidgustafik7968]

Oh, and if you try this route, check whether the materials you'd use do not form whiskers. Stuff like tin, silver, cadmium, zinc have been known to have these problems.

[@nixieloxar]

I really admire your patience and perseverance in solving the problems step by step, I would have lost my nerve long ago... great job!

[@SeanBZA]

Thinking you enlarged the purge gas feed tube, and put a second coaxial tube in the bung, so that you could have the purge gas flowing at high velocity in the tube, and venting out through a smaller diameter inner tube, using a needle valve, and a flexible rotary seal on the outside on the larger glass. Then simply have 3 solenoid valves, and 3 different flow meters in parallel, so that you have a high rate of flow initially, to get turbulent flow in the envelope to purge out the glass rapidly, then this drops to a lower flow, enough to keep the glass filled, and compensate for leakage past the front glass and via the vent tube, and then a third lower flow rate for the sealing time, where it can provide a low flow for sealing and annealing, with the restriction keeping internal pressure low so the glass does not blow out. Small tube ends just short of the anode cup, so the flow is mostly from the front, or you also put a hole in the cup so the tube is just short of it, and the majority of gas comes from the front of the cup to purge there, and the rear larger tube provides flow to the outside of the cup, both keeping the sides cooler, and also keeping the fine structures colder.

[@mumblbeebee6546]

Fascinating - great engineering design process. It makes me truly happy that you keep walking this technology path!

[@AleksServisMan]

Isn't it easier to use a special compound instead of soldering glass to glue the glass? It is used in flat EFD and CRT displays, for example. The junction only needs to be sanded so that there is a flat plane.

[@el_es]

CRTs also have the black surround around the edge which would be kinda off for this one; and CRTs specifically did have the mask / mask wires black and not trying to make it glow...

[@williamcohron2380]

It interesting to see how you arrive at problems, work through the failure analysis, and then develop solutions to those problems. Obviously, there may be more than one approach to a problem, but I applaud the determination and effort. Keep up the good work! Looking forward to the next video.

[@peakinout1]

Please keep trying , they are staggeringly beautiful . Maybe one day I will be able to afford one ! Fantastic work !

[@donaldasayers]

Have you considered 'solder glasses' low melting point glasses used in the days of cathode ray TVs to join the front phosphor coated screen to the back of the tube. I know nothing more apart from the name and the fact that they existed. They were used to prevent exactly the sort of problem you are experiencing particularly with shadow mask tubes. You are putting purging gas in, but is there anywhere for the air to get out?

[@cathedrow]

Why stainless steel electrodes? Wouldn’t it be better to have electrodes plated with something more inert - gold, platinum, palladium, osmium etc?

[@BenjiKimba]

Nice to see the whole development from a product !

[@benashbenash]

Vaše práce Dalibore, mne nepřestává fascinovat. Možná to již v diskusi někdo zmínil, nečetl jsem, anglicky dobře nevládnu. Zbarvení kovu do modra až hněda se používá jako cílená technika v hodinářství případně šperkařství a mám zato, že souvisí s konkrétní teplotou, na kterou se součástka ohřeje, aby se zbarvila oxidačním procesem. Rozsah teplot je cca240-320stC. Chápu, že zabránit ohřevu tenkých drátků uvnitř baňky je těžko řešitelné. Proti oxidaci svarů nerezové oceli se používají mořící pasty, či gely, které se nanesou před svařováním a poté se umyjí. Představuji si jak by se asi baňka po uzavření vypírala a i to se mi jeví celkem komplikované. Třetí věc co mne napadla je zcela jinak řešená baňka, která by se uzavírala v jiném místě a možná i práce v jiné poloze. Pokud by baňka byla vyrobena jako kádinka a po vložení elektrod by se uzavírala víčkem s komínkem, navrhoval bych polohu svisle, kde víčko by se dávalo shora a do baňky by se zaváděl těžší plyn (argon) který by mohl elektrody pod sebou chránit. Přeji mnoho úspěchů v dalším bádání. Ps: přimlouval bych se za české titulky :)

[@bobvines00]

I was going to ask if there is a way to add a second "tube" next to the existing purge tube so that it could be an "exit" path for trapped gasses, but now I'm looking forward to your solution. I have no idea how to add a second tube without some kind of fancy (expensive!?) rotating gas fitting(s). (Since I don't do glasswork, I _know_ almost nothing about what you can and cannot do with glasswork, so I'm not aware of what methods could be used to implement a wild (silly?) idea like mine.)

[@huub8]

I don’t think that would in fact require special rotating fixings. The tube connected as the gas inlet is the only one that needs to be connected. So a hole off-center next to it should be enough to let the gas out. You would only need a fancy rotation coupling if you would also want to collect the expelled gasses, but that isn’t being done now anyways. If you do go this route, I would consider adding an intentional restriction in the additional outlet, so that the gasses will only make use of it when the front is sealed.

[@tinygriffy]

A Neon Tube Bottle Ship would really rock !!! maybe you can design digits that way, so you can create the whole envelope and shove in and unfold the digits later. .. ;P

[@xDevscom_EE]

Thank you for sharing these attempts, it's very educational and makes me want to delve into glassworking :-)

[@wood0366]

I'd try having the join further back if the primary problem is heating and oxidizing the digits; use the metallic shield to thermally isolate the digits. Additionally, try having two tubes feeding into the through the base tube itself, one with the nitrogen and hydrogen gas ending with something to disperse it, the other acting as a vent. Also, perhaps seeing how much annealing you actually need for the tube.

[@LiveeviL6969]

Dang I jumped! Wasn't ready for that.

[@tomasberger9980]

Just an idea. Is Oxidation really oxidation? It could possibly be nitrides.

[@zyeborm]

I was having the exact same thought

[@orionsmith7668]

What about trying a tube within a tube from the back? Supply and exhaust so you can purge constantly without a pressure increase. Seems much easier than dual tube entry points. Could make the purge supply the inner tube and extend inside.

[@pasikavecpruhovany7777]

For the shorting problem, support between the digits may still be worth trying. (I really liked the previous font more) Something unnoticeable like tiny glass beads the size of grain of sand on the back side of the digits in the place where they overlap.

[@мр.Олександр]

Очень круто! Надеюсь когда-нибудь приобрести у вас несколько ламп для часов) это будет предел мечтаний)

[@HomeDistiller]

Have you thought of using the evacuation stem on the side to introduce the purging gas? That way you could keep the flow going during the whole process

[@FarleyHillBilly]

Stainless 301 is used for paste masks, because it is good enough. Stainless 304 is more corrosion resistant but more expensive. Also try argon as a purge gas.

[@mhbh1979]

Love it Dalibor, your work is absolutely outstanding. I see you fixed the problem. I have a very old possibly pre WW2 CRT and the equipment it was in. Only a 3 inch CRT with X and Y plates coming out of the neck. It used a 16KV final anode voltage!. It has just a second evacuation pip on the neck. No need to get the gas to circulate as the pressures are so low. Something like Brownian motion takes place. I can send you some pictures of this weird of all weird CRT's if you like. It is an odd one but it clearly works and I think the glass work at least may help you. I know you do a neon fill etc. Cheers Matt

[@ImTheReal]

19:55 Where are your safety glasses? Thanks for sharing Pretty cool as always!

[@michaelturner4457]

That's what I thought. I'm from the UK, and in an industrial setting where machining is going on like lathe work. Eye protection must be worn. It's Health & Safety rules here.

[@stevencooper2464]

Hello, fellow QCAD user; have you considered applying a voltage to the elements while welding on the glass front? You would need to equip your lathe with a slip-ring assembly, and figure out the best voltage, frequency, and polarity to repel the oxygen molecules (if there is such a possiblity). Just an idea.

[@motherjoon]

I love this series

[@aserta]

I wonder if the solution to the floppy digits isn't more tabs and cross over lines and rather adding a little bit more thickness to the material and upping the requirements to run it. I have seen (sorry, can't remember where they were from) tubes with thicker parts. It was an 'indicator' tube, used to show arrows, so a series of lines arrayed like this /|\ (and rotated in a cross for the four sides) which had particularly thick lines. I think, it must've been at least 1.2 mm thick or there about. It was used in an old elevator from the 50's, unfortunately, the tube no longer exists as an item, i saw the carcass on the ground during a survey. :(

[@lufog]

Maybe try to lay a flexible tube through the hole in the back wall before sealing and leave half the diameter for gas to escape? So that gas enters and exits from the same hole. And at the end of the sealing work, pull out this tube. I hope I made myself clear, I don't speak English well.

[@Ammo1313]

Could you use a flat piece of glass for the front and combine that with an outlet tube that maintains a preferred pressure to purge and dome the front glass to what you want it to be?

[@SignalDitch]

I'm excited to see how you solved this problem. I'm guessing you'll have tried a central hole in the anode cup and two concentric pipes for purge gas. That said, does anyone know if it would be viable to simply allow the oxidation and then pump it down, backfill with pure hydrogen and heat up the elements with an induction heater? In any case, I'm following this project with excitement

[@ChiralSymmetry]

A few random, probably useless, thoughts occur to me: (1) There could be surface-adsorption of gases and moisture inside the tube. When annealing, all the interior surfaces that get hot, might out-gas moisture and/or oxygen, that then oxidizes the digits. Perhaps pre-heating the entire-assembly might drive-off any moisture and/or gas adsorbed onto surfaces? (2) If you can sacrifice a few tubes, maybe smoke would help you visualize the flow of the purging-gas? Then you could get some idea if the oxygen is being purged everywhere. Plus, you might be able to see if the jet from the burners is blowing air into the tube, when you melt the edges. The smoke would contaminate the inside, but might be worth trying. There are smoke generators used by people who study ventilation of buildings. Sometimes it's a machine, sometimes it's a special stick that I think they light on fire. I suppose, even a vape might work, but not sure. (3) For stupid reasons, I wonder if argon might be useful as a purging gas. This is silly, but the idea is that argon is heavier than air. So as the tube fills, centrifugal forces may tend to push the argon towards the seam. I have no idea if that would help or not (because maybe argon would stay away from the center). (4) Other silly idea: Measure the temperature inside the tube, near the digits. Then do experiments where you put digits at that temperature at different levels of oxygen purging. This is to get some idea of how much oxygen can remain, without oxidizing the digits.

[@MichaelOfRohan]

These tubes come out SO nice

[@nobodynoone2500]

Huh, too early to use a getter i suppose... Perhaps a different purge setup/gas/immersion? Or an acid to remove it inside the glass?

[@kaunomedis7926]

Fill it with H2 and heat up with induction coil. The oxides on digits will be reduced to pure metal and water.

[@Gorgula]

I was thinking inductive heating too, for multiple reasons.

[@jeffgough8862]

Why not simply drill a second small hole through the bung so there is an additional exit path and leave the purge gas flowing through the whole welding procedure?

[@stephenfreeth7593]

would RF heating of the Digits during the welding of the glass stop what looks like the oxidization of the digits , are the gasses condensing on the cold digits ,

[@CKOD]

Welp, cant wait to see what the fix is, if its not letting the digits oxidize in the first place, or if its fixing them afterwards. You already are using reducing gas to purge, so fixing them afterwards may be doable. Plasma cleaning in a reducing gas atmosphere?

[@daliborfarny]

First!

[@mumblbeebee6546]

LOL! 🧡

[@MichaelOfRohan]

Wait.. thats illegal!!

[@AleksServisMan]

Ну ты и жук! :)

[@MichaelOfRohan]

@@AleksServisMan i am SO pissed that yourube prevents the "copy to clipboard" on comment text. Makes translation impossible

[@AleksServisMan]

@@MichaelOfRohan оn a PC, you can select text, then press CTRL+C to copy and CTRL+V to paste the copied text. ;)

[@FrankDrebin]

Could oxidation be removed chemically after sealing the front or digits are already damaged?

[@nutwiss]

Sounds like you may have a solution already, but, seeing as your glass envelope isn't yet sealed, is there any reason you can't chemically strip the oxidation with, say, nitric acid, then go through the standard chemistry glassware cleaning process (wash with water, wash with acetone, air dry)? Would this damage / etch the stainless steel? Would this be a bad thing if it did?

[@el_es]

Might be a problem with the connecting wires which are enamel-ed.

[@HeyBirt]

I guess since you already solved the problem suggestions are not helpful. I was guessing that during annealing the internal gas temp of the tube decreases which would tend to draw in outside air. Perhaps instead of turning off the purging gas switch from flow regulation to pressure regulation, at 1bar, which should prevent over pressurization as well as outside air from being drawn in. If the internal gas temperature increases for any reason during annealing it could still lead to over pressurization unless there is an overpressure release.

[@Papinak2]

I had the same idea. Plus, the electrodes might keep relatively high temperatures for quite some time. Also, I had idea of some sacrificial piece of material, which would oxidize quicker than the stainless steel, to consume oxygen that gets in anyway.. But that'd probably interfere with function of the tube.

[@apo_chromatic]

Will these tubes be available to individuals once they’ve gone into production?

[@daliborfarny]

I hope so!

[@nixietubes]

Maybe change the shape of the anode cup/front glass piece to stop the digits from getting so hot? (The anode cup could absorb some heat)

[@kentswan3230]

The purging gas has to flow into the anode cup. Feeding the purging gas coaxially is more consistant with production. Why don't you try suffient numbers of small perferations in the anode cup so that gas flows more consistantly through the entire volume. To keep the front lens clean, providing several outlets on the body circumferece would allow the purging gas an place to exit wthout over pressurizing the tube during sealing and anealing. These can be closed off before moving on to the back sealing and neon gas filling.

[@seemannseeheim6175]

could you use a double-walled glass tube at the end of the gas supply? so you could flush and regulate a low constant pressure

[@Flying0Dismount]

Is it possible to switch to vacuum immediately after you seal, and then refill with purge before annealing, that way you get rid of any oxygen that may have entered and get fresh purge.

[@PinballAtelier]

Great work! Thanks for sharing so many details. About the oxidation problem: would it be possible to solve the oxidation by means of a mild acidic solution afterwards?

[@stephenrowley4171]

I wonder if light coating if some form of flux in the digits would help? Allthough obviously that introduces it's own problems.

[@studiochefson3573]

Thanks for the spoiler!

[@neffk]

Add a bleeder so after the front is sealed there is still flow of the purge gas? That way those edges are still being flushed even after closing

[@robertjakobe7809]

Tohle je velmi zajímavý a specifický problém zajímalo by mě jestli je nutné aby zadek baňky s přívodem plynu byl uzavřený jestli by nebylo možné ho nechat otevřený a pouze statickou trubičkou přivést plyn dovnitř co nejblíže k anodovému plechu a nechat ho zase hrdlem vytékat ven možná by to stačilo k vytvoření ochranné atmosféry a proudící plyn by mohl pomoct odvádět teplo z kovových částí uvnitř takž by se nemuseli kroutit a při nižší teplotě je taky menší šance že by kov oxydoval tolik. Přeci jen mi přijde nekonečná škoda do tak krásné baňky dělat ve předu díru.

[@t850]

...coat (galvanize) digits with silver or gold from the front side (back is not visible so it's not necessary) and oxidation shouldn't be a problem...:/

[@andymouse]

Maybe two holes for purge gas an inlet and an outlet next to each other so flow can can maintained at a positive pressure throughout the process with controlled needle valves. During annealing use infra red or halogen heating instead of gas. Some sort of enclosure around the work that is at a positive pressure at all times during the process. How clean are your purge gasses and how dry are they ? and is temperature a factor ? how are the digits stored prior to installation and front bonding ? there are a lot of factors at work and I look forward to your final solution !...cheers.

[@samsical2597]

would it be feasible to drill a vent hole in the chuck out the back of the tube, where the gas is introduced and add a hole in the anode cup? then just press the front on and purge for a couple minutes before heating/sealing?

[@mahbucket1]

Could you maybe make the whole front of the tube a one piece dish and fuse the glass together where the metal backing plate could protect the digits from being heated at all? Also as others have suggested make a second hole in the gas bung so you don't have to turn off the gas?

[@Spirit532]

I know you said you already solved the issue, but have you considered short hydrogen plasma bursts? Not enough to damage the back plate or the oxide(?) coated wires, but enough to strip the interference-thin oxide on the digits, since that's the only place where it's unintentional.

[@briswolf]

Maybe a dumb idea but can you chemically (or electrochemically) remove the oxidation after sealing? Or would it be too hard to get the inside of the tube clean again?

[@andypughtube]

Can you place something more reactive in the tube to preferentially react with the oxygen? Like a getter, in fact. It could be left in there, or maybe removed before final sealing.

[@FetKiller]

Would using hydrogen for the fuel on the torches make a difference? Probably not because it’s the oxygen from the air which causing the issue. Could the front plate be put on vertically maybe the purging gas would rise in the tube to cover the digits in a more uniform manner. Just some thoughts. I have the greatest respect for what you have built over the last decade it is truly inspiring!!! Thank you for sharing the journey!

[@aserta]

About the oxidation, with the preface that chemistry is not my main bread and butter, but i tangentially deal with it, have you tried figuring out a chemical coating that's heat resistant, but would be easily removed by introduction another chemical before or during the sealing process? I wouldn't know what that could be, but there's gotta be something that prevents oxidation during the work, and can then later be removed and thus save you the hassle. Chemistry is wide and all knowing, sooo maybe find a local chemist or two and ask them?

[@stephenfreeth7593]

strap all the digits together and apply a high DC EHT voltage between them and the anode during welding so any gasses are attracted to the anode not the digits

[@dronehubsanzinoprozino2vid3]

Why not overcoat digits by PVD coatings like CrN ? could help, easy to test.....

[@xgvargas]

Can't you use vacuum during the annealing process?

[@valvemonky4734]

did you use a different gas to purge in the end to solve the problem and have you consider selling any of the failed tubes as a big nixie paper weight?

[@kay486]

Would plating the digits with some other metal help reduce the oxidation without introducing other problems?

[@s0rc3]

This is what i was thinking, maybe Rhodium

[@travismiller5548]

Arnold Gruppe has been toying with lasers at the glass lathe... might be an oxygen free solution for you.

[@MikrySoft]

I wonder if you could remove oxidation from the digits after sealing by filling the tube with 100% hydrogen (to avoid nitrides forming) and heating the digits from the inside (with an induction heater for example)

[@MikrySoft]

From looking at some research papers you would need to heat the digits to 1100°C for hydrogen reduction to work, so light yellow glow, a bit lighter than the nixie glow.

[@borayurt66]

Since you solved the problem already this has no point but, may I ask why (instead of fighting the oxidation) is it not possible to make the digits out of another metal that doesn't get oxidized? Or maybe plate the existing digits with some metal (gold?) that doesn't get oxidized?

[@borayurt66]

@Dalibor Farný you've got spammers.

[@Richard.Andersson]

Is it possible to use another metal than stainless steel? For example silver plated steel or other nobel metal that does not oxidize as easily (silver oxide converts back to pure silver and oxygen gas at a few hundred degrees, hence more heat would be better in that case, so perhaps ageing can be done faster at etc.)

[@daliborfarny]

It should be stainless steel as other metals sputter faster. Thin coating of inert metal should be ok - we might try it in the future. Thank you

[@paulvandergroen9569]

@@daliborfarny Nickel electrodes and a small quantity of mercury in the neon gas mix to prevent sputtering.

[@SciDIY]

Is it possible to etch the oxide layer afterward?

[@DantalionNl]

Perhaps you could try having a sacrificial piece of metal inside the tube that is more likely to oxidize than the metal you are using for the digits. The idea is this piece of metal then consumes the remaining oxygen.

[@arvidhjort]

What cameras are you using? Cheers!

[@s0rc3]

Could you rhodium plate the digits to reduce oxidation?

[@edgeeffect]

Could you use a low level vacuum instead of purging gas?

[@Splomf]

No, as the seal between the front face and the rest doesn't exist yet

[@tecnoaddicted]

maybe silly questions, maybe already tryed: what about """ glueing""" the two pieces of glass? there are a lot of powerful bi component and or epoxy even trnasparent that may suit with good mechanical resistance. think airplanes " sandwich" windows. silly?

[@brianmunyon5669]

I wonder if pure Argon would be better?

[@TrapperAaron]

You might be having issues w the hydrogen purge. Hydrogen embrittlement in the steel could be the problem.

[@michaelturner4457]

19:40 The operator wasn't wearing any eye protection? :O

[@Unfinished80]

Are the digits etched or laser cut? Thanks for another great video! I love watching the progress

[@MichaelOfRohan]

My assumption is laser

[@daliborfarny]

Etched

[@Unfinished80]

They look great! Very clean lines.

[@killpidone]

What if you coat the back of the grid numbers with something non conductive like a ceramic coating although I have no idea what off gassing might look for that

[@killpidone]

You might also get better results with limiting oxidation leaving your glass in a vacuum chamber for a period of time

[@FarleyHillBilly]

Why not seal the faceplate on with epoxy. there are suitable low vapor pressure types available, it's not like it's high vacuum.

[@travismiller5548]

attach argon solenoid switch to lathe on a magnetic base. such that when you move in the tail stock to apply the lens, the gas is switched off.

[@graealex]

Next test: flood the whole workshop with purging gas, to see whether the torch is the culprit.

[@ophello]

This entire nixie design seems to have been plagued by a host of design problems. At what point do you say “we should have built it smaller”? It seems like all the issues are due to its enormous size.

[@Sigmatechnica]

what? you solved the problem? that's not fair i don't get to give armchair expert advice! D:

[@stephenfreeth7593]

thinking out loud might be nonsense

[@FlippieCoetser]

How about just making a few holes in the metal cup to improve the flow and keep the rest the same?

[@FarleyHillBilly]

There are more 'text me on...' messages hidden amongst the replies 100% sure this ia a scam