I have a CRT rebuilding station

[dreyfoos]

I have a CRT rebuilding station

Rather than add to the current threads “Will CRT Rebuilders Disappear…,” or “If a Picture Tube…,” over in the old color TV forum, I have decided to advance the discussion by posting a new thread in both forums. Perhaps that's a no-no. If so, I apologize in advance. But this matter certainly spans both forums. The CRT rebuild topic – so vital to the hobby - might even justify a sticky.

I have a never used CRT rebuilding station. It is a product of C.R.T. Equipment Company of Nashville and it was shipped in 1970. It was listed on eBay last February but closed with no takers. I had many reservations about making this rescue attempt but I could imagine it in a museum if nothing else. It was in imminent danger of being parted out for the motor, pump, and steel. This is heavy equipment. The fact that it was less than an hour by pickup truck from my location made it possible. The owner accepted my offer and it now sits in my San Francisco Bay area garage. This outfit was designed for a mom and pop TV repair shop – artisan work – in limited space – one jug at a time. It’s not a multi-tube production outfit, not automated, but it is state of the art – for the 1960’s. It consists of two units: first there is the impressive vertical lathe with a variac on the motor and with oxygen and natural gas jets for welding necks, neck-gun units, buttons, or whatever is needed. Second, there is the gas oven to bake gasses out of the glass and a two-stage pump system to evacuate the air. There’s a tipoff coil and an RF bomber (using big ol’ honkin’ jumbo tubes) to vaporize or flash the new gun’s getter material in 20 seconds or so by induction heating through the glass neck of the tube. There is a panel of gauges and switches and pots to monitor and control voltages, current draw, etc. including the process of aging the new rebuild.

The story goes that the kit had been purchased by a father who was trying to set his son up in a business. Apparently this was bad timing as the rebuild business was fading fast by the time this was shipped in 1970 – and the son must have had other fish to fry. So it sat in the San Jose garage for 36 years until it appeared in an estate sale. This kit came with a variety of small hand tools such as the hot wire neck cutter, a file to nick the glass, a ruler for neck length, and the heater to soften and collapse (tip off) the glass evacuation tube to seal the new vacuum. It even included some now unlabeled chemical – probably for cleaning the tube necks. Yes, it also came with a few trays of new guns and bases. The assortment was what you would expect for 1970. There are some for the old roundie black and whites as well as for the 21 inch roundie colors. There are also some that would be for the newer 110 degree small neck tubes. The problem with the guns is, that if nothing else, the barium getter material has not aged well. It’s kinda “gone.” It’s been a long time since I worked in the chemistry area and my duties had nothing to do with getter chemistry but I have read that the shelf life for the getter material is more like days than months and certainly not years. The kit also included an interesting factory instruction manual. Alas, it does not even include a schematic of the RF unit – but that’s not a big deal. The real hitch is that it doesn’t include a Harry Potter wizard to fill in all the gaps – the “black art” that would give the first tube out of the oven a high probability of success. There is enough variability in the dud, the equipment, the operator, etc., that one really needs the voice of experience looking over one’s shoulder.

So, I wrote an e-mail to Scotty at Hawkeye last summer but for some reason have never received any response. I tried to make it clear that my goal was not to compete with him because we all know that old TV restoration is a moderately costly and crazy hobby – not a moneymaker. We will pony up $38 each for Moto 7 gaskets but Ed’s Radio Service will be doing well to break even after meeting the initial demand. We are collectors because we need the challenge and, also, for the memories – not for the bank account. My concern – that others have voiced – is that the Hawkeye operation in Iowa is the last “goin’ Jesse” that we know of, and who knows whether it will continue for days or years – nobody’s immortal. When all the black and white roundie tubes finally run out of cathode – or simply don’t exist – In fifty years – or whenever – I would like to think that a backup plan would be in place that will allow our collections to outlive us. I suggested to Scotty that he allow me to schedule a visit and make a high resolution historical video record of the A to Z of a rebuild – a day in the life of a picture tube rebuilder. I also suggested that it be done on one of my duds – at his going price, of course. My purpose would be to try to get some of that “black art” recorded for posterity. So far, I’ve found no written procedure for the steps in a rebuild other than what I have in the instruction book for this set of equipment. If any of you could step forward with tales from your misspent youth as an apprentice in a rebuilding operation or with some bound or loose leaf pages entitled “Everything You Ever Wanted to Know about Pix Tube Rebuilding” then it would be most welcome. There should be exploration of this topic in the old magazines for the service trade. Or, if you are a museum or an individual who wants to dedicate the space or even a chunk of your time towards getting at least one tube out the door to prove that it can be done with this equipment, then let’s talk. This equipment is “priceless” but if whoever ends up with it might consider giving me the firstborn or two as a token of appreciation. The garage where it now resides also houses my own collection and is not the space it needs. It needs a natural gas supply and oxygen, water for cooling the pump, and it’s own circuit breaker. The equipment’s footprint is only about 3’ by 8’ but you would probably need at least a bench of that same size and space for oxygen tanks, etc. The gun challenge: I have no idea who Hawkeye’s source is. Steve McVoy might have a lead. I suspect that the N.O.S. guns I have could be “refreshed.” I also agree that China or Eastern Europe tube factories are a possibility and I have a Chinese-American friend who could translate the needed inquiries. Perhaps a 50+ year-old used gun could be rebuilt. This isn’t rocket science – just simple Harry Potter magic stuff. Hey, is this really that much more difficult than the Moto 7 gasket challenge? As Steve also mentioned, the best way would be for someone to apprentice to Scotty long enough sweep floors and learn the art. Would anyone else care to approach Scotty on this? Does he have a son ready to step into his shoes? Hello? Save those duds! …Roger Dreyfoos.

[kx250rider]

I wondered what happened to that outfit! I thought about rescuing it too. I used to go to Dunbar (a rebuilder in Los Angeles until closing down in the 90s.) I watched most of their processes, but sadly did not take any notes nor get specifics. The process as I recall it was:

Acid wash the whole tube to remove the aquadag, labels, etc etc

Poke a hole in the side of the neck near the pins with a tiny white-hot tipped iron to relieve the vacuum

Using the wire hot loop, crack and remove the neck

Measure and install the new gun using the lathe with the circle of gas flames

Now is where I'm fuzzy; not sure in which order the following:

Place in the oven, connect the vacuum pump to the protruding long glass tube from the new gun, bake, pinch off the glass tube after evacuated, flash getter (???), bench test the tube for several hours with a TV chasss while waiting for all the shorts to pop off, then finally install the implosion band and spray with Aquadag.

Somebody may remember the rest of the process, and that experience will be a big bonus above the books.

I bet Tom Ryan can add some to this

Charles

[Tubejunke]

Don't you have to spray phosphur on the inside of the faceplate before you put on the gun? That is for black and white at least. What I'm wondering is this. What do rebuilders do with these color tubes that I think had in some cases a metal screen of some sort behind the faceplate? There would be no way to refurbish that type other than replace the gun I guess. Of course the gun is going to be the problem in a tube needing rebuilding. Is that all they do is replace the gun?

I have an old article from the 40's somewhere about how a crt factory operates. Really neat story with great pictures. That is where I saw them spraying in the phosphur.

[ChrisW6ATV]

Rebuilding never includes renewing or replacing the phosphor, that I know of. The company I work for used to have CRTs rebuilt in Chicago for the airport information displays we support. When we were short of good duds to be rebuilt, we had our supplier rebuild some with "only minor" phopshor burns on their faces from the fixed arrival/departure information that had been displayed. (Most dud CRTs we used to replace have severe burns from the high-contrast, fixed information.)

[kx250rider]

They can re-phosphor a B&W tube, it's an extra fee. Not a big deal, at least back when the were rebuilding tubes alot. Color tubes; impossible.

Charles

[mbates14]

see obtaining guns are a problem, BUT cant you take the old gun and sorta change out the cathodes? and it be good again? its a possibility, but you would have to be very good at it with alignment patterns and stuff.

[dreyfoos]

I want to bring everyone up to date on the CRT rebuilding equipment – which is now a CRT rebuilding project. I have heard from many of you and I do appreciate all the input. Special thanks for those bits and pieces of the “black art” that several of you have posted and which may prove to be critical in helping to put the puzzle together. Keep it coming. But not to me. I’m pleased to announce that Steve McVoy has taken this on as a project for the Early Television Foundation Museum in Hilliard, Ohio – a suburb of Columbus (where you can probably still find real potato chips). As I understand this would first and foremost be a preservation project – to house the equipment in a museum where it can actually be seen and inspected by every person who is interested enough to make the pilgrimage to the heavenly hills of Hilliard (I’m guessing about the heavenly part – I have yet to visit there myself).

It goes without saying that many of you, including Steve and me, would like to see this equipment achieve its intended purpose – not to go into competition with anybody – but to make an effort to see that we, as collectors, are never left high and dry when it comes to freshening up those picture tubes that will keep our collections alive – especially those which are more near and dear to us: the 3KP4, 7JP4, 10BP4/FP4, 12LP4/KP4. Well that’s as much as I can lift. But others might have larger tubes in mind and there’s always the heavy lifters – the true masochists – who have to have it brought to you in “living color”. The equipment might even be able to handle a 30BP4 for the humongous DuMont – but that’s out of my lifting league. When this equipment goes out my door, the future of it will be up to Steve. Is there any one of us who wouldn’t like to see it fired up – if nothing else to try some dry runs to make sure everything works? I’ve heard something about his plans and they sound ambitious but practical. If you have ideas or comments – then by all means send them along to Steve via [email protected].

Thanks to the internet we in California scanned and e-mailed the instruction manual for this equipment to Steve and he now has a link to it on the museum’s site under “restoration/rebuilding.” Perhaps it will jar your memory and elicit some more pieces to the puzzle – anybody out there ever re-phosphored a tube? Know anyone who might have?

And just remember there was a time, not so long ago, when those CRT gaskets for the Motorola 7”ers were unobtanium.

Roger Dreyfoos

[bgadow]

Excellent! The museum is first rate. Good things are going to come of this.

[Big Dave]

I emailed Steve and I am volunteering not only to run gas and electric to the equipment, but I am also interested in learning the trade. This could be a weekend thing, especizlly when work is slow.