 Greetings, and welcome to episode 19 of taking apart a Monroe K series calculator, actually putting it back together again. So I'm Rob. You'll notice some differences. The previous episode actually had a very short intro section that just said 18. And it had some music, which is kind of cool. It's Creative Commons music. So I put the link to where you can get that down below. So check it out. Anyway, so this is episode 19, and according to the episodes that we have previously done, we are currently working backwards, putting the machine back together again. We are now working our way backwards through episode 9, which is taking apart the keyboard mechanism. And, of course, we will be putting it back together again during this episode. So what I've done is I've laid out all the parts, and since there are very many parts, I can't actually get it all in one shot, so I'm just going to do this handheld. And that's why you see me, because I'm doing a little introduction. So let me show you all the parts. So here we go. Here is basically a wide shot of all the parts that go into the keyboard mechanism. So the microphone is not doing so well. So here we have the plate that all the little keys go into. These are little things that go on the sides of the plate. And you can see these little U-shaped indentations. That's where the carriage movement axle goes. These things are for locking and clearing the keyboard. These things are these sort of bars that go across the plate, so that when you press a key, they actually lock the key in. This sort of double axle thing is the mechanism which actually clears the keyboard out. Here are a whole bunch of key stems. There's a lot of them, well, 80 of them, because this is an 8x10 keyboard. Here are a bunch of springs. And here are a bunch of washers and a couple supports. There's a little thing with a set screw in it. And also these other funny non-round shapes are actually key stem locks. So you can probably see how it all works in episode 9, but we're probably just going to do it again explaining it. Now the reason that these are on napkins is that what I did was I took this stuff, I took this stuff, industrial maintenance coating thinner, which this is a California product. See, it says use in place of MEK, toluene, xylene, and blah, blah, blah. That's all stuff that is not legal to use in California because cancer, I'm sure not that this doesn't cause cancer, I'm sure it does, just like everything else, I guess. And here is a bucket and a toothbrush. So basically what I did was I poured some of this into the bucket. And with the toothbrush, I just basically cleaned this plate. Oh God, was it dirty. All of these larger parts I cleaned with the toothbrush. All of these parts I then dumped into the bucket, poured the thinner over it, and then just agitated the pail for about a minute or so, and it came out really clean. These especially were almost black with grease. And all I did was, again, I just dumped it into the pail, agitated it for a minute or two, and then pulled them out, and they were nice and shiny. Same deal with these. I mean, these were really gunked up. So anyway, that's what I did. And what's left, in fact, let me move the microphone again, what's left is this bag. And in this bag, I'm not going to open it yet, are all the pieces of felt. I think there's probably 160 pieces of felt, or so, two for each key stem. I also left all of the screws, there's a screw, and all of the springs in here. I didn't want to clean them because they're kind of really small parts and I didn't want them to get lost. So I could probably hand clean them or they may not even need to be cleaned. So those are all the parts that go into the keyboard, and now we will put the keyboard back together again. All right. To put the keyboard back together again, we've got to work backwards. The first thing we've got to do is take the plate and orient it properly. So to begin with, what we're going to do is place the plate so that these standoffs are facing up and so that this notch is to the left. Next thing that we're going to have to do is pick one of these and put them on this side. So the question is, all right, well, is it this one or is it this one? And you can see that they are slightly different. One's got a bigger U than the other one. But the way you figure it out is that you can see that there are these pins on the end, and they, when they're put onto the plate, face inward. And the reason for that is that these bars have little holes on the end, and the holes go on the pins like this so that these can rock back and forth. And the only way for that to happen is if the pins are facing each other. So there's no pin on the other side. That means that, and the U, must go on the right side. So that means that there's only one of these that can possibly fit so that the pins are facing in and that the U is on the side and that is this one, because this obviously isn't going to do it. So what you do is you have these alignment pins and you have these holes for screws. And you simply put that in and it just goes in like that. Now the next thing that you have to do is apply some screws so that we can attach this to the plate. So we have, I've taken the felt out of the bag along with the smaller parts. We have ten springs. They all look approximately the same. One is slightly smaller, but I'm not sure that that matters. And then we have six small screws and two large screws. So the first thing we're going to do is, on the plate, we have basically four screw holes. We're going to screw the middle two using small screws. So let's do that now. I'm just going to take this, put it in there, that's one, two. And some of the small screws are slightly smaller than the others, but again I think that's just because the exact size doesn't really matter. And it doesn't look like they were any good at making precisely sized screws, anyway, aside from their threads, which of course they had to get right. So I'm just screwing this in with one screw, this is a magnetized tip so sometimes it just sort of hangs in. Okay, so there we go, alright. Now for this, we have these side pieces. And these side pieces hold this in place. And this is the zeroing mechanism. So let's see how we put that piece on. So first of all, it's important to orient this piece the right way. So it looks like this is going to go, I'm looking at the video right now and I'm trying to see, I'm pretty sure, uh-huh, okay. So this is actually going to go like this, with the lever on the side opposite the notch, like that. And we have this bushing which goes over here and that will eventually hold it in place. So the next thing is these things. So you can see that there is a long hole and a round hole and the long hole is for the pin. So obviously it will either go like this or like this. So we have to figure out which it is. So in other words, this is either going to be held off the board or it's going to be held on the board. So I'm just going to very quickly consult the video and it looks like it is actually held off the board, like that. And in fact, I think I may be incorrect. I think this may actually go, let me just orient this the way the video is showing. So it looks like it's like this. Okay, I'm just holding it up like this, right? No. There we go. I got it oriented the way the video is showing. I think that's correct, yes. Now according to this, it looks like we're holding this up like this. So actually, that's right, okay. This lever is on the same side as the notch. And the reason for that is that there is a spring that goes from this hole in the lever to this hole on the edge of the plate. So that's why this goes like this. And then it is actually held off the board, which means that when I put these on, they basically have to go like that, just like that. So what I'm going to do is, let's see, can I, if I were to, I'm just planning this out a bit. Yeah, right. So I'm trying to figure out whether to screw these in first. Well, I guess it doesn't really matter. So I'm going to screw in this one using the long screws, right? Because we're moving through more material, and that's why two of the screws are longer. So I'm just going to screw the one bushing into place, great. It's kind of odd the way that this hole is elongated, because that sort of implies that this thing could move back and forth. But of course it can't, because that screw fixes it in place. So I'm not really sure what the deal is on that. Okay, so then we will put this other one. Now if I do that, the question is, can I get this in? Probably. I don't want to put the axle in first, because then I won't be able to put the screw in. Because the axle is in the way, and that's no good. So again, using a long screw, I'm simply going to put the bushing in its location on the other side of the plate, screwing it in with the long screw. So there we go. So now I take the axle, and on the long end I'm going to insert that over on the left side. Okay. Now I can just insert it on the right side all the way, basically, or almost all the way. Because the next step is, we're going to take this bushing with the set screw, and we're going to, does the set screw go inside or outside? It actually goes inside. Okay, so I didn't do this correctly. The bushing goes on first. Actually let me put some oil on that. I refilled my oil container. So let me just put some oil on that, so that it's easy to go on. And so that it doesn't, I don't know, rust in place or something. Okay. So I'm going to put that right on there. Nice. I'm also going to just put a drop of oil on each, on the inner side of these surfaces and maybe a little bit over here, because this is actually going to be a moving part. So all right. So now I just put the long end in, put the short end in. Now I move the axle, the bushing over, like that, to fix it in place. See? It doesn't move. Now because these two surfaces are touching and they're going to be moving, I'm going to put some oil on there as well. Okay. And the same thing on this surface. Okay. Great. Now I'm going to take my screwdriver and holding the axle in position. I'm going to tighten the set screw. Set screw is tightened and there it is, distributing the oil a bit. Okay. It's not, it doesn't move completely freely. There is obviously friction. You can see that it is holding its own weight. But I don't think that's too important, all right? I can put the spring on now. I'll just use the spring that's small. So the spring will go on one end. So these are hook end springs. They're called hook end. The reason is that of course it's a spring and it's got a hook on the end. So you've got to put the hook into the hole without actually distorting the hook. So there's one and then over here, I'm just going to put that in there, get it in to the hole. There we go. So that's how that works. Okay. Now you can see how the zeroing mechanism now works because we have two different types of key stems. One is a zero key and the other is 139. The zero key stem would of course fit in like this, see? So that this tab sticks out and obviously when I pull on this axle, it's going to pull on that key stem if the key stem were perfectly straight up and down, which of course it's not constrained to at this point. It will be when we put it in the casing of course, but for now that's basically how that would work. So this would pull the zero key down as if you were pressing it. Next thing that we're going to do is we will turn the plate upside down. So we have this rail over here and on the rail are eight little holes and those holes are four springs. These guys. So we have nine springs left. We're just going to separate off eight of them. Again they're the same size or approximately the same size so we can just pick any one. And what we're going to do is place the screws so that they are hooked in and they basically just hang right over there. And these springs are specifically for these little bars here. And the other end of the spring goes into this hole. And then, or is it this way? Yeah it's this way, I'm pretty sure. So if I put one of these in place, get on there, okay and imagine that it's held on the other side. So this spring is going to go over here and it's basically going to hold this bar into place and the bar can rotate this way and the spring will pull it back this way. The reason for that is that the key stems have these funny little cutouts over here. And when the cutouts are, I think I would have to put this stem through one of the holes. Let me do that, that, okay. So you can see that if I push the key down now, it's kind of hard to see, but if I push the key down, that will rotate the bar and then the bar will snap back into place due to the action of the spring and then this is now pressed down in place. In order to clear all the keys, basically what you would have to do is have a bar running the full length, pushing all of these rock bars like this whereupon this can spring back up and then you release it and it just goes like that and then you can press this down again like that. So that's basically how the keyboard works. Here is the spring that goes on to the key stem that forces it up when the bar is released and then it springs back up. So that's basically how it works. So let me take these out again. So that's why we have these eight springs because there is one of these bars for, there's a bar for each row. So I'm just going to put these springs on. I thought I might be able to do this by hand, but I guess not. So again these are hook ends. So I'm just going to take the spring and hook it over the end. In terms of whether it gets hooked on like this or like this, it doesn't really matter because it'll just stay in there in the end so you can just do it whatever way is most convenient for you. Again, pulling gently, pulling just enough to get the hook over and into the hole without actually bending the hook. So here's spring number three. I'm just going to pull it slightly and then put it into its hole, oops, totally lost the hole. There we go, number three, number four, number five, and I'm doing this first rather than after all the key stems are in because you can see that it's a lot easier to put the springs in before all the key stems are actually sticking up here and getting in the way. So now one thing that occurred to me is that after I cleaned all of these metal parts, I did not apply anything that would prevent rust and I'm not sure if that's a mistake or not. Clearly on all the moving parts I put some oil on there so that's obviously going to help. But in terms of the surfaces and the non-moving parts, I don't know, I mean I heard bad things about WD-40 so I'm certainly not going to use that. There is, Crudcutter makes a derusting liquid or stuff that is supposed to simultaneously remove rust and protect the metal against rust, I don't know. So I'm just going to leave it like this and kind of hope for the best. Besides in 30 years the singularity is going to happen and we won't be around to take apart these calculators so nobody is actually going, so there's not going to be enough time for this thing to rust. 2045 is when the singularity happens and we'll all upload and have a great time. So anyway, okay so that's that. So the next step is we need to put the key stems on. So we'll start with the zero key stems and what I want to do is basically put the key stem in here from the bottom, right, so it goes in like that and I'm not certain whether I have to put a washer with a piece of felt in there, here's a washer, here's a piece of felt, I think I do, and that goes in like that. Well obviously it would have to go in. Let me just check the video to see if we do get washer and felt on the underside. The reason that we would put a washer and felt is for example for this key stem, which definitely takes one of these. So we put a washer first and then a piece of felt and that goes in like this. So when the key gets pressed down, this happens, but then the key, and there's a spring on the other side, so that when the key gets released, it smacks into the plate. And obviously you don't want that smacking sound to be very harsh and metallic, which is why they put this felt over here. So they would do that and then on this side they actually have a spring, okay, and then this thing, this little piece actually fits into this notch over here, this little slot, and holds this in along with another washer. So that's how the spring gets held on. So basically you do that for all the keys except possibly for the zero key. So I'm going to check the video on that, and then I'll come back. Alright so I checked the video and indeed, at least according to the video, which I believe, each one of the zeros does take a washer and a piece of felt. So it's difficult to put the washer and felt on first, like this, and then stick this in because the washer just sort of gets in the way. So you can see that it's good to put these zero key stems in first because that tells you the orientation of the notches. Because if this were oriented like this, then this little tab would not be able to hit the axle, which means that the notches must go like this. So what I'm going to do, I guess, is I'm going to, let's see, can I swing this out of the way? No, because if I swing it out of the way I'll never be able to swing it back. So basically I'm just going to put the washer and felt just on the plate and then move it in place. That's it. That's all I have to do. And then I have to pull on it a little bit. Why isn't it going stuck on something? I think it's stuck on something. There we go. Okay, so basically that's this side and then on this side, I'll turn the plate around like this. The first thing you need to do is put on a spring. So here's a spring. Just put it on like that and this will work for all the other things as well. The next thing that you need to do is take a washer and just put it on. And the final thing we do is take one of these locking things and you take pliers and you hold on to the locking bit and we're going to, let's see, how can I orient this? I guess that's okay. And what you have to do is push down on the washer, stick the thing inside, which is kind of difficult, but it can be done without dropping anything. So once you get one or two of these done, you kind of get the hang of it and then you can do the rest of it pretty quickly. So you just sort of jam it in there and it locks in place like that. See? That's how it works. Now of course, because this key has freedom to move like this, it's not going to move very smoothly unless it's perfectly straight up and down. And that happens when the top plate gets put on. So anyway, okay, so I think it's time for a time lapse. Okay, so I'm actually going to stop here and the reason that I'm going to do that is, first of all, you can see that we've pretty much run out of felts. We have four, probably seven left and we obviously need 12. So number one, we're missing five. And number two, these are the worst felts that there are. Some of them are just ripped. Some of them have been flattened out and distorted. So I'm just going to go to a craft store or something and get some more brown felt and then cut it into a circle and then just cut a slot into it somehow. So that's the easy part. One thing that I did notice as I put this together and I'm not sure if you can actually see this, so I'm going to put, so you can see that one of these stems is different than the other. One of these stems is not the same. So this one on top is actually bent slightly and I'm feeling it and I can actually feel the metal having been distorted right over here. Now I could bend it back, but the problem is that whenever you bend metal, you fatigue it. So this will be quite fragile. I think I mentioned a while back that I had actually 3D printed one of these. It was actually a curvy bit. So what I'm going to do is I'm going to get another one of these 3D printed that's flat and just use that instead of this. That's the nice thing about 3D printing. The bad thing about 3D printing is that it's still quite expensive. I don't remember how much I paid for that little piece, but I suspect that this is going to be anywhere between $15 and $30, which if you think about it as compared to the cost of one of these things from eBay, it would be ridiculous to actually, it would not be economical to 3D print something like that. But the alternative is to take one of these machines from eBay and use it for parts and basically just say that you're going to basically take one out of circulation. If you really wanted that one back into circulation, you would have to replace all of its parts that you pulled off of it. So in the end, I guess it sort of evens out, but yeah. So the point is to 3D print or not to 3D print or to replace or not to replace. And I would argue in favor of replacing because if you don't replace, then you're taking one machine out of circulation, at least one. So let's see. Just make sure we have all the parts that we think we're supposed to have. So there's five, well that's weird. We've got some parts missing. Oh no, we don't, sorry. There are eight per row. So there we go, eight and two. So yeah, and therefore we needed 10 felts and we have seven felts here. So we are missing three felts. And in terms of these, as I was putting these together, I was looking at this small part really wondering what I should call it. It looks like a t-shirt, so I'm just going to call them t-shirts. So obviously we need 10 t-shirts and 20 washers. So we've got five washers, we've got 10 washers, we've got 15 washers, 20 washers, 26 washers. What? Did I count that right? I know we have 10 stems, oh yeah, because I didn't put on the tops of these yet. So that would be 26 washers in total. So that means that in terms of t-shirts I would need 16 t-shirts, so let's just make sure I have 16 t-shirts, that's four, eight, 16 t-shirts, good. So I've got all the parts, with the exception of the one bent key stem. And I'm going to replace all of these felts because these are all distorted or ripped. And oh, and we have springs. I'm just going to sort of assume that we have the right number of springs because why wouldn't we? We seem to have all the parts anyway and we were very careful in putting parts back into bags. So that's going to be it for this episode. When we return next time we're going to finish the keyboard assembly and I guess that means we're going to move on to the main frame, which is kind of cool. So until next time, this is Rob signing off. See ya.