The Bendix G15 Typewriter is Crazy Pants! 

Regarding the lowercase t, there are two issues. One is, you are correct, the alignment may be out. The faces of the slugs are curved to match the platen, and have to hit the platen at just the right angle. There should be a pair of adjustment screw that set the limits of travel of the typebasket--one for uppercase and one for lowercase. You can tweak them until each letter is uniform from top to bottom. The other issue is the. Literally, the. As in, the word, "the." "The" is, of course, the most typed word in the English language. And the "t" and "h" are typed with opposite hands, which means that even a moderately fast typist sometimes hits them so fast that they land on top of each other. Most English-speakers type "teh" fairly regularly, regardless of whether the keyboard is electronic or mechanical. What that means, in practice, is that on old typewriters, the lower-case "t" is often very badly chowdered, as a result of slamming into its neighbor "h" so often. Especially on electric typewriters, where the collision has some force behind it. I got through high school and college with old second-hand typewriters, and I can't recall ever having one on which the "t" was in good shape. So do not use the lowercase "t" to set the typebasket alignment.

i love how the table rocks when the carriage hits the end stops

This brings back memories, some of them good. I used to repair these IBM Model C typewriters, along with Model D and Selectric, back in the early 1970s. I noticed a few things. The carriage shouldn't make that grinding sound when you hit return. Your escapement pawl is dragging on the rack. There should be a link from the vicinity of the carriage return cam (possibly the carriage return clutch, I don't really remember) to the escapement pawl that unloads the pawl from the rack when you engage carriage return. Adjust the clevis one-half turn at a time until the pawl stops dragging. What you called a friction roller is known as the power roll. Yours looks pretty worn, which is to be expected. I don't know if anyone is still making that part, but yours should be replaced if possible. To remove the power roll, first latch your carriage return clutch. If you don't, the disc will slip out and it's fiddly to reposition. Remove the drive belt from the motor and the big cogwheel from the power roll shaft. You can then remove the screws holding the power roll bearing in place and slide the power roll out of the left side of the machine. You may want to do this anyway so you can clean the old hardened grease from the power roll shaft and the bearing and add new grease. We used to use 1,1,1-trichloroethane to clean the rubber parts because we didn't know any better. It did a great job but it has been phased out because it's an ozone-depleting chemical and a probable carcinogen. I may or may not have discovered that it also does a great job of killing cockroaches and getting one high. I ain't sayin' nothin'. 🙂 Try to find someone who knows these machines and can assist you. Don't trust my memory. It's been 50 years, after all.

When you press that DC button it's going to be a huge moment, I think everyone is going to have to cross their fingers, but looking forward to it and best of luck.

9:11 - "RELEASE THE PLATEN!!"

I can't believe that I now live at the time when there are 70 year old computers

My 4 year old “why did he shave his beard off?”😂

When I worked for Xerox we used a spray rubber restorer that was actually just straight D-limonene. The stuff works amazing, smells great, and won't try to kill you.

Probably the *upper and lowercase stops*, if its anything like a normal typewriter it would be a pair of 2 large bolts that have several adjustments on them, and generally have rubber rings to cushion the rise and fall of the basket. However those rubber rings degrade and it gets out of whack. The manual would tell you how to adjust it, especially equipment from IBM. Cryptic language from the ancient engineers aside, it wouldn't be that bad.

It looks like the friction drum is worn more for frequently used letters. Id guess that would be the best place to start to get the lower case letters working well again. Thanks for the video, its fun to see the old school tech. 😊

Watching that carriage return actions puts all kinds of context into the design criteria of the Steelcase series of desks from that era.

Ah you've found an ultra widescreen typewriter. Nicw

I typically work a Sunday through Thursday schedule, so I always start out my week with an Usagi Electric video. Watching David solving problems gives me a lot of motivation to solve my own. This week's problem is trying to get two MCUs to exchange data over a UART connection that suddenly stopped working for no reason. The scope traces seem to match so I am clueless. But I've seen David solve some seemingly unsolvable problems right here on this channel, so I'm confident that I'll figure it out at some point. 🙂

My guess on the u-z hex notation is that it was inspired by calculus/algebra and how most variables are a set of those letters

If nobody hasn’t already commented about it, the black roller is the platen. The thing that holds it is the carriage. Still pretty impressive.

~70 odd years of corrosion on those contacts and in those solenoids is going to be so much fun later on.

I learned to type on a IBM. (Yes I am that old). The lower case letters are used more often. The ink ribbon has an upper 1/2 for capital letters and a bottom 1/2 for lower case letters. Lower case is used more that capital letters. Perhaps the first thing to check is the ribbon. I don't know what a new ribbon might cost but it could save a lot of time and money

Love this lovely type (hah) of stuff. I am very excited to see the Bendix alive. that thing is a beast. We had a very quiet day, n I was having a bit of a tiff with my boss. He told me to clean my desk. I will admit it looked like chaos, but I had about 80% of the things I might need within arms reach on on a whole stack of shelves and boxes. instead of touching that, I took him literally and scrubbed the desk. including the keyboard and mouse to a ridiculous level. every key removed and scrubbed. So incredibly filthy. years of workshop filth, every type of grease and solvent, wire trimmings, tiny washers, SMD resistors and capacitors and transistors. and just that grotty human slime that accumulates. I was in a big workshop, everything was filthy, we worked on stuff that was inherently covered in mud and grease, so I didnt really care. But it was SO NICE to have such a clean keyboard. its was cleaner and shinier than when they are new (It was *my* keyboard, I have a particular IBM model from around '98 I love, and bought a box of them from a surplus store. I've worn out 4 of them so far, but they type so nice) Id moved stuff out of the way to scrub the desk, but put it right back. so the desk itself was absolutely gleaming, but the chaos surrounding it was still all there. Very satisfying. especially when the boss came by a few hours later just before knockoff. see, the 'Desk" is clean! he was an asshole, so I played his game.

What a dapper young man 😂

Hard to believe all this is from 1956, looks so refined. Finland started building a computer in 1954 and after 6 years of hard labor it was operating but made of leftover bits and trash from other countries. The hard drive had gears from a milk separator.

Interesting as I worked as a typewriter repair engineer back in the 80's & I used to leave the IBM to the person who taught me who is still alive. My curse was to carry these machines back to the workshop. I sat in anticipation as expecting your issues so good luck & look forward in interest.

I love it, especially when you got the carridge moving fully. The whole table moved at each end stop... amazing. Nice work as always

Lovely! It's neat to see this typewriter working; even if the lowercase letters aren't exactly in line with the platen. This is like the Final Boss of Typewriter World, it would seem!

This typewriter seems to be the ideal size for drawing/filling in old weather maps with symbols of meteorological phenomena and information.

I was a draftsman back in the 1970s & 80s, and we had typists, with wide carriage typewriters to type large amounts of text on our drawings. This was extremely helpful to us, otherwise we’d have to hand letter this stuff. It was advanced technology at the time. The carriage allowed a 24” X 36” sheet to fit.

At Bendix, someone was told that size matters apparently.

The parts you call hammers are properly called typebars. Enjoy your vlogs very much. Keep it up.

Thank you for increasing my appreciation of the home computer. I love vintage computers just because they’re complexity, but I’m in all of the home computer for it, seeming some publicity and where it originated from.

At 8:56 I was immediately reminded of the similarity to the construction of IBM's 3270 type terminal keyboards. (IMHO that is STILL, even today, the best terminal ever designed.)

Oh it is you again :) I overlooked it when I saw the thumbnail. It was so much fun to watch. Great recording and narration.

A new Usagi Electric video every Sunday is my favorite part of the week! Happy Easter Bunday!

Hello David, It's been a blast watching you breathe new life into old computers. It's fascinating for me to witness how it all started from humble beginnings and how much ingenuity went into it. Nowadays, the technology behind it all isn't as visibly intricate. It's almost become my Sunday ritual to tune in. I'm aware that the effort might not seem worthwhile and it's a lot of tinkering that doesn't necessarily yield practical results. But it would be intriguing to see the typewriter or the punch card reader in a test environment, perhaps with an Arduino... Sending warm greetings from Austria! Also, I must say, you really do look young without the beard! It's funny how shaving and haircuts seem to alternate... almost like my routine! Cheers!

They made special pliers to adjust those typebars; they were designed to grip the head of the typebar without damaging the type.

Awesome! I can't wait for the DC! See you at VCFEast!

Ever since you introduced this printer I’ve been wondering how the paper moves with the platen. Is there a big tray attached to the carriage? I’m guessing it uses some sort of continuous roll or fan fold. Very curious to see how this goes. Thanks for sharing this with us.

the earth's orbit shifts a little each time that carriage hits home.

Cannot wait to get all the currents up!

I love the cantilever braces on each side, necessary because THE platen is SO WIDE!

10:09 even old electronics have screws behind the feet, wait, the feet are the screw themselves? 🤯

Very impressive old technology so much details and mechanics its pure beauty!

That terminal is a beast. Looking forward to DC being applied!

Make sure it’s at flaps 40 when you land that thing, those wings need as much help as they can get.

The rubber platen underneath that drives the white cams when a character is selected is called a power roll. It has dried out and become hard causing the white individual cams to slip on the power roll when engaged instead of being grabbed and driven in turn pulling the type bar and type face up to and striking the platen. The white cams wear as well and may be causing additional slippage when engaging the power roll. 50 years ago you would have the platen and power roll recovered by a company that does just that. New rubber of a specific type, softness etc. In Canada, back then, it was Randmar Platens in Quebec for us eastern Canadian technicians. Who could do that now I don't know given we live in a throwaway society now. Very little grease is used on a typewriter rather machine oil is best for what is available to day. Be carefull with using grease of any type as it will cause you a world of headaches if over done. The alignment of the typefaces to the platen is fine. No problems there but your ink ribbon is done. In the day we cleaned he platen, power roll and feed rollers with Benzine. Yeap straight out of the bottle onto a rag and wipe thoroughly. Different times. If you look at the serial number on your unit there should be a letter at the beginning of the number and I think your typewriter is a model B. Whichever letter it is that is the model of the basic typewriter you have before it became a printer. Cheers 🇨🇦

The missing screw-on switch knobs at the front of the typewriter look like they might be the same as the ones for the pickup selector on Gibson Les Paul guitars.

I’m thinking of all the engineers who worked so hard to design this beast and bring it to life even though they’re anonymous and surely all deceased. A moment of silence in their memory on this Easter.

Wide carriages are often used for accounting. When I had worked for a "math museum", we had quite a collection of desk calculators and typewriter hybrids. Most of them had those huge carriages. They were used for processing spreadsheets. You can perform calculations and label them. There are also were pure calculators and pure typewriters in use back then. So it's not a "computer thing", maybe they thought converting an accounting typewriter is more versatile and can't do any harm - except for someone sitting on the edge of your desk. The Zuse Z25 of the museum uses a standard Siemens T100 Teletype with a slight modification. It has a red light when the computer expects you to "type" and a switch which can alter the flow of the program. The light is just the RS232 "Request to send" Line equivalent and indicates that the computer is actually listening. The Z25 is also meant to be used by teletype lines using ordinary teletypes. So the Z25 is actually a "home office" capable computer. The way this works is absolutely genius! Letters are commands and numbers are parameters. The ABC/123 switching code tells the Z25 that the command is complete and you are now entering numerical parameters. Fpr example, the "copy" command ist "U" (Umspeichern). If you press the command letter twice (e.g. "UU"), the machine automatically uses double-words. So switching from 18-bit to 36 bits was easy. No need to learn new commands. Also the machine does hardware floating point math. And 36-bits floating point precision using simple commands is really impressive and the machine handles this really fast.

Adjusting the print position of the typeslugs is actually pretty simple on this machine. I recommend heading over to Phoenix Typewriter and find his video on that adjustment, they’ll be different brands and models, but the process is the same.

Oh what an over designed monster that typewriter is! I briefly played long long ago with one of those with a normal width carriage. It was the standard computer console on a CDC-160A minicomputer. The interface electronics were about a tenth of those on this Bendix computer. I wonder how and why they went so bizarro on this interface. I think the default interface, however complex, was still only printing numbers and spaces and newline. They had as an option an alphanumeric options which required considerable rewiring in the computer chassis. Part of the printing problem may be due to the rubber sleeve on the platen. That hardens up over the years and makes a huge difference in how the letters strike the ribbon and paper. I used to have a Kleinschmidt T-100 teletype back in the 1970’s. A mechanical gem but its printing was almost illegible due to a hardened platen. You might try some rubber renewer on it. An excellent one is oil of wintergreen which does an amazing job of softening up rock hard rubber. It’s great for restoring rubber idler wheels on turntables. A new rubber platen is probably way out of production.

From someone who grew up in the typewriter age, that lever at 18:30 that goes from A to F is to adjust the platen for when you are making multiple copies using carbon paper. Some of your viewers may now be wondering, "what's carbon paper?" I will leave it to the Internet to answer that question for them.

my engineering brain is telling me that you should sand the lower friction roller so it's even all the way across, then wrap it in electrical tape, as there's notches that have worn in from where the bottom of the hammers contact the roller.

Love your channel and videos! I used to have the basic typewriter that your beast is based on. And yes, it shook the desk every time you hit return. I can almost smell the oil from the electric motor bearings as I watch the machine run. BTW, I worked in a computer repair shop that resold used computers. To clean them up, we used a SImple Green/Dawn dish soap combo in a spray bottle, with just a little water to thin it down a smidge. The Dawn breaks down the "people grease" (oil from people's hands) better than SG alone.

4:04 "its so big" "its starting to grow on me" "How often do you get to play with a 28inch 'platen'" the 3 contenders for out of context quotes of the day

Seeing a platen THAT BIG on a typewriter, and an electric one at that, is pretty wild! There's still a typewriter shop in Mesa, not far from me, that's been there since the 1940's, and that's exactly where I'd take it! I still have a manual typewriter that I got at a garage sale many years ago, and I took it to the shop in Mesa for a cleaning; the owner (son of the founder) didn't bat an eye, even though it's about as old as his shop. Good thing you have a guy who can come to you, though. 🙂

7:04 I am currently playing around on an emulated C64 (childhood memories) and there is a bit of pesky memorizing to do since a modern keyboard is not a C64 keyboard. But when I saw that Bendix keyboard layout, I realized I have nothing to complain about.

wow man. brave of you to take that thing apart

This is advanced level vintage computing.

Great work looking forward to DC.. As for setting up the mechanics of the teleprinter you did right in passing this to someone tuned into that device, you skills are epic.. I know that teleprinters and typewriters can be a challenge, I remember the Creed 75 RPTK which used an aggregate motion mechanism to translate motion in three planes to the drum type head. Move R and loose the Y and vis a versa. Even a drop too much oil would through the alignment. The IBM Golfball was a dream to set up. Teletype 33 responded well to kinetic adjustment. Best

"Initially I thought it's too big but it's starting to grow on me." ;-)

Eagerly awaiting the first power-on of the CPU circuitry within the Bendix G15 computer as once it starts up, it could be one of a very few vacuum tube computers still functioning. Also, either mechanical or digital typewriters, depending on whenever they're made, made with huge carriages tend to be for budgeting and scientific applications, as it's usually good to have a bit more information printed on the papers. You also can get the printer to function with digital load drivers (buffers, potentially with beefy MOSFETs, depending on whether they're meant to indirectly or directly drive the mechanism within) and even a $1 Raspberry Pi Pico microcontroller or any of your favorite microcontrollers, particularly to test the oldest digital printers to make sure it works all the way throughout, something with the Quick Fox Jumping over The Lazy dog "hello world" to test all alphabets and anything else you want to test, even using them as a proper Linux TTY device if you so desire.

Thanks for the video.

13:51 It has a dedicated pin for Doom!

My father was a photolithographer and I grew up in a darkroom with ultra large format process cameras. The platen on that IBM typewriter caught my attention because I've seen that sort of thing before. They were on typewriters dedicated to the manually justifying type. So just to let you know its not a feature restricted to first generation mini computers.

Nice cleanup on that old monster! Look around for a bottle of "platen restorer". The rubber on the platen and drive roller gets hard with age. This was a common problem with all typewriters of this general design, and a stopgap before replacing the parts was to use platen restorer. Getting the drive roller a little less slippery (with the restorer) should give more velocity to the hammers, and hopefully you can run the machine on the default B setting. You also need a new ribbon. Should be able to find ribbons for an IBM Executive reasonably easily. I've got a very similar machine. It is still IBM color, and has either a 16- or 18-inch platen, I forget which. It was originally the main output device on a GE computer used for QC inspection on the tin plating line at Kaiser Steel in Fontana, California. It has the same solenoid and key switch arrangement that you have on yours, but the electronics box was separate from the typewriter, and it just had big honking cables running out of it. Back in the late 70s or early 80s I built an interface and software to use it on my KIM-1. Slooow...

Beleive it or not, I learned how to program a G-15 in college. By that time, Bendix had been bought by Control Data. So here are some thoughts: 1. As you have seen, the care and feeding of the memory drum is EXTREMELY IMPORTANT. As I recall, due to the very tight fitment of the read/write heads warmup and cool off of the drum has precise instructions. The one thing I remember was after use, the computer had to cool off for several hours before restarting or a head crash will occur. I could not help noticing the gouges in the other drum probably from not following those directions. I also know that the sequence for starting the computer required following precisely a sequence of power starts or again there would be head crash. Once gouged, they are difficult to impossible to rebuild. 2. Long programs were never entered on the keyboard. We used a device called a Flexowriter to punch the five level tape. It was also hooked up to the G-15 to use the tape reader on the Flexowriter to input the code. You could also manually pull the punch tape through the upper reader on the G-15. We used that upper reader primarily to load the operating system onto the computer. It was also used to load diagnostics for trouble shooting. The tape cassettes took forever to load and sometimes failed requiring a reload. 3. As mentioned previously, the computer knew no language other than machine language on startup. We had several sets of cassettes with different computer languages to load into the operating system. The only one I can remember was called Algol. 4. Maintenance took a boatload of contact cleaner. The filaments on the dual triode tubes were run lower than manufacturer specifications to increase to longevity of the tubes. That part of the troubleshooting was easy, if the filaments were not lit, that was your defective tube.

I just passed second chapter, starting third, but I am already excited to see this machine going back to life!

For the tools, components and knowledge they had, our grandparents were miraculously ingenious.

hand drawn circuits are pretty.. Always loved the look of curved traces..

It's very odd to see you without a beard yet you look so much younger. I think the beard gives you a level of authority and adds to your wisdom😂

The keyboard and switch layout on the G15 Typewriter Terminal makes it look like a smiley face...that's winking at us! Hahaha! 😂 This must have been the typewriter Andre The Giant wrote his memoir on. 🤣🤣

Very exciting stuff on the verge of happening🤞

17:13 No chemicals (e.g. alcohol, petrol jelly, etc.) used to clean the platen. Well done!

This brings me back to the times I had to service Friden Flexowriters that served a similar purpose. A wonder of metal rods, clutches, relais etc etc. Noisy as hell! Some would even do (mechanical) proportional spacing. We even had a model that supported Ascii coding on an attached 8 channel paper tape reader/punch. Ah the good old times ...

I love that 28" machine, it's the original widescreen format. For when you don't want your spaghetti code to have to conform to that pesky 80 char column limit!

That's really interesting that it supports breakpoints. I always assumed that was a convenience of more modern software debugging systems.

Made my day with this one, wow!! Will you running off some large format ASCII art once you get that bastard operational? I would totally buy a poster of that. Love all the Bendix videos, keep up the good work 👍

I do love the Russ... IBM green color. The same lovely hue I loved/hated in the DC-9 cockpit

That keyboard roller underneath REALLY reminds me of the arrangement for driving the keys on a Linotype!

That’s awesome. Not only the resurrection, the unique (did you say, “42 inch platen”?) dimensions! ❤ There is 1 mod’ I recommend. A lamp inside the window of the printer’s power indicator. Maybe a couple of NE-2 lamps, which would be period correct. Your skillset may not cover fine tuning of typewriters, but your skills and results (with all the beautifully restored equipment behind you), is truly, outstanding and inspirational! I am envious. I’m looking forward to the next instalment of the Bendix system revival 😍. It will also be impressive, if you can demonstrate a working program (ie, tic-tac-toe loaded from paper tape).

Remarkable progress on this thingy. You might try finding another ribbon. It looks like it's getting kind of dry. That might resolve the lower-case printing problem without a lot of mechanical stuff. I seem to remember that adjuster on the right for hammer force actually adjusts the distance between the platen and the hammer just slightly... Play with that incrementally until a "best quality" print results. Good work on this, man. I'm looking forward to the day you push the big green button.

I love this electro mechanical stuff. A work of art. Congrats on getting it cleaned up and working. So cool! For a split second, I thought I saw one or these used on the Loki series. I just looked back and I think it's just a standard IBM electric typewriter but with a large platen. Not a massive one like the Bendix. BTW, check out S2:E6 at 46:32 if you want to see what I mean.

wow, that's a mad machine! You need a concrete pedestal, there's so much weigh moving there!

Wheeeeeeeee! Wheeeeeeeeee! I'm riding the carriage! What a beautiful machine :) It looks like it's badly in need of recapping, to do it true justice. For some reason it impresses me even more than the Selectric! Minty fresh with a hint of Tektronix teal. Good luck with VCF East, and beat Jeri at pinball this time, haha! CuriousMarc will be there too.

just an FYI with these old typewriters, use a backing sheet of thick paper. Especially with such a novel long paten. Old platen can be indented and damaged by the types striking the paper and it. cracks might ensure

My very first job was with the Autonetics Division of North American Aviation at Downey California in 1957. We had a Bendix G15 computer with an attached DDA (Digital Differential Analyzer) . Among the idiosyncrasies of the DDA were that you had to keep the keep the curve plotter pens in the cooling fans exhaust port. The warm air kept the pens warm eough to write reliably, otherwise they skip. Sometimes a vacuum tube or two would get microphonic (an unintended output caused by mechanical vibration). The standard, but not authorized procedure to detect probems included tapping on the racks where the tubes were mounted. Once in a while it worked.

Happy Easter, bunny guy!

The term "Absolute Unit" comes to mind when looking at that thing.

I started watching this actually thinking it was an April fool's video. That thing is ridiculous! 😂

Back in the 1960s, I worked on a slightly more modern computer called a LGP-30. It was also a tube computer with a drum. The typewriter was a Flexowriter and the hexadecimal codes were zero through nine, then FGJKQW. The typewriter also had a tape reader and could be run independently using that reader. The thing that strikes me about the typewriter in this video is the difficulty of managing paper. It must flop around quite a bit.

If you can get the power roller out, you should be able to get in touch with JJ Short Associates to have it redone, they put new rubber on the original parts, platens, paper rollers, and power rollers, you send your parts off to them and they come back with new rubber. Lot of typewriter collectors use them.

They make specialized cleaning solutions for platens. You should try AF Platenclene Cleaning Solution. It's what I use on the pressure sealing machines we use at work. Simple Green is fab stuff but it is mostly soap and water which could dry out the rubber.

I had one these as a plain short platten IBM typewriter which had been through a flood. It took forever to clean out the mud. My Waterloo was that the motor was a goner and I was never able to find a motor of the correct dimensions even though it was a fairly normal looking fractional horsepower motor. The plastic rollers and internal rotating bar for activating the type hammers were an interesting method , a bit like a piano - not even close at all to the Selectric technology which followed.

come for the vintage computing, stay for the massive black shafts being stroked with care and devotion

It looks beautiful and every mark left is like a badge of honor and speaks to is past!

The ribbon, of course, is dry but you have experience in that fix. You came a long way in this video.

So cool! Just subbed!.

You can just use a piece of regular papir to "scrub" rubber-rollers. You are correct not to use any chemicals or degreaser, as it might cause rollers to harden up and (potentially) slip.

You seem to have to do alot of cleaning of grubby old things (me too!) I highly recommend Krud Kutter for things like that dirty case. It's stronger than most cleaners like Simple Green and Windex but won't move paint like Goofoff and others. Sometimes a better cleaner is better than elbow grease which can cause unwanted abrasions.

-10 years for this shave! sheesh!

Just WOW!!!!!! Fun video.

That think is cray cray and amazing.