 Hi, welcome to the next episode of Reverse Engineering, a Monro K calculator. We are in the middle of putting this thing back together. All right, so the next thing is we've got this selector axle. It's called a selector axle because when you push these gears together, you get varying number of teeth and that selects the digit that you're going to register. So it goes, let me lift this a little bit, okay, so it goes in this cradle. So this gear is going to mesh with a small gear that's inside here. It's also going to sit on these friction brakes right here, so we need to make sure that we get that correct. And let's just do that now. So the friction brake, I believe, sits in here and in here down there. So they're kind of pulley-like structures. So I'm just going to go ahead and align this one and I think it just sort of snaps into place and align this one and that also snaps into place and I'm not going to lubricate them because they're supposed to be brakes. So now the next thing is that I do need to press this in so that as you can see, these gears are not quite meshing. That's because this needs to be pressed in more. So what I'm going to do is I'm going to, I think what might help is if I rotate this a little bit so that this cam surface is not touching this lifter. There we go, that works. So the other thing, ah, okay, timing, right? We've got a set of timing marks and it looks like I got it right. Oops, I think I'm off by one tooth. Let me move it over by one tooth. Yeah, there we go. So I've got to get the relative phase of the gears all correct and that all-important timing mark tells you where it goes. Okay, so that's that. What I really want to do, now in bag five I had one tiny piece left and that tiny piece is this little wire which is right here, this little wire and what this little wire did was it connected this little lever on top of here. So basically this served the purpose of the clip and I believe what I was going to do was find a replacement for the, find a standard, you know, C-clip replacement or E-clip replacement for this. So, but before I do that really what I want to do is I want to lock this down because we've got these screw holes here, here, here and here for half bushing. So what I want to do first is get those half bushings in place so that I can keep this axle so that, you know, I'm not like, you know, accidentally lifting this axle up. So let's do that and that would be in bag four, which is this bag, I'm pretty sure. So I'm just going to have a quick look inside at what parts we've got. So let me just clear my working area, here's my little screw and what have we gotten bag for? Well, we've got a whole bunch of parts, a lot of which we won't need but we've got the bell hammer, we've got the bell and various other parts and one of these, okay, so here we've got the two bushings and we've got one, two, three, four screws of the same kind. So that's what we'll use. So let's do that. Let us compare the bushings to see if they're the same, indeed they do look the same. So as before, I'm going to oil the threads, okay, so that my screws don't rust in place and then I'm going to put one bushing on and just put the screw on finger tight and this other screw on finger tight as well and the other bushing on the other side as well with its screws, finger tight, so now I'm just going to tighten that down and this other one down and this one, I suppose you can't really see that, but it's there and this one is again kind of hard to get to so I suspect they just used like a really long, thin screwdriver so I've got a thin screwdriver here, so I'm just going to use that, yeah, I'm pretty sure that's what they must have done, what the ancients did with their screwdrivers, their crazy custom tools, non-standard, right, okay, good, nice, so that works. Let me just apply a bit of oil to the little bits in there and to the edge of these cams because they are rotating, alright, so let's just give it a rotation, it seems to get stuck at a certain point and that's really not good, uh-huh, okay, so what is preventing this from working properly? I think it just had to align, that's all, I think, unless I'm just trying to see how this actually works, okay, so we've got this cam surface here, alright, which drives this lever, which allows this lever to come up and down, so if I rotate this cam, you can see now there's nothing here, but now the cam pushes the surface down, I believe, yeah, so now this is basically locked in place, but if I rotate it a little more, now it's able to come up, actually like that. Now the question is, what about this guy on this side? Well, it too has a cam surface and it appears to be slightly different, so you can see that now it goes up like that, so that's kind of, kind of odd, not really sure what the deal is there, as you can see that these two things sort of pop up and go down at different times, really not sure why that is, so this is kind of a mystery, so, okay, so clearly this is in the locked position because the rollers are down, right, and as I rotate this, now that's interesting, okay, as I rotate this, so this is in the locked position, now as I rotate this, this comes up, which basically means that I'm now allowed to lift the carriage up, I guess, although this will not let me lift the carriage up, so as I continue, this now pulls the carriage, pulls this lock down, and then this pops up, so I think something screwy is going on here, and I'm wondering what that is, so one possibility, this is a very distinct possibility, a bloody awful possibility, is that I have maybe, possibly, this cam I put on at 180 degrees, I'll bet that's what it is, I'll bet this cam I put on 180 degrees out of phase with this, that would certainly explain why these are popping up, why one pops up, then the other pops up, then the first one pops up, okay, all right, that is very good to know, so, and then the question is, well, unless maybe this is actually correct, and this is the one that is out of phase, all right, so it turned out that it wasn't that the parts were put on improperly, it's that this thing, I can actually pull this out, rotate it, and then put it back, and then it has a certain range of movement, and if I rotate it, turn it around, and put it back again, it has a different range of motion, so obviously I need to match that range of motion with this over here, so if this surface is like that, then clearly this surface also needs to be like that, now they, now I can put it back, so let me raise the brakes, so this is an important and interesting piece of information, at least I think so, so the brakes are on, let me rotate the gears so that they are timed properly, so actually even before I remove the gears, and I rotate this, I can see that that the gears rotate, see that, that's interesting, that is a mechanism, let me, let me remove this because I want to get to the bottom of this, this is a mechanism that requires a full cycle to be done before, before inverting the cycle, so I'm just going to rotate this until it comes back, there we go, so this is, this would be the neutral position, now if I rotate it, if I start, you know, doing an addition say, or a subtraction or whatever this is, now I can't rotate it back, I must complete the subtraction, or the addition, okay, and when it goes back into the neutral position, then I can go back, and you see, I have to complete the cycle, so I actually want to know where that mechanism is, and I suspect that it is going to have to do with this mystery, let's see, this mystery pin, oops, darn it, I'm pretty sure that's what it is, yeah, and in fact as I rotate this, let's rotate it a little more, okay, so now we can see that there's this tooth gear here, and this, essentially it's a pawl, and it prevents it from moving backwards until the cycle is complete, then you can actually go in the other direction, and the pawl, again, works in the opposite direction, so that's the purpose of that pin, that's pretty neat, something I didn't know, how tight does it have to be, well, I don't know, that's the question that I was asking before, let me just look at this, put the microphone back on my shirt, which I keep forgetting to do, where is, here we go, right, let me see if I can just sort of lift the camera a bit, and get to the spot where I'm working, all right, there we go, so we're looking at this nut here, and this is the pin thing, so if I were to just attempt to tighten it a bit, so I'm just trying to tighten that nut there, and it's still loose, which is good, and it being loose, I'm going to put some oil on it, and I'll put some oil on its pin also, so that's pretty cool, all right, so let's go ahead and rotate this so that the arrow over here on the intermediate gear, the middle gear is pointing up, and let's go ahead and put that selector gear back on, now of course I'm going to have to make sure that I have these cam surfaces pointing in the same way, and then carefully put the brake on there, good, then rotate so that the arrow is facing down, and then maybe rotate the cam a little bit, rotate it a little more maybe, what I want to do is push this gear down, and I'm being prevented from doing that by this, I think, yeah, I think, yep, all right, so let me get the alignment exact, so let me lower this, so that maybe you'll have a hope of seeing the arrows boring lowering, so there's the arrow there, now I need to rotate this, match them up, there we go, now they're matched up, now I'm going to raise the camera, and now I'm going to put the bushings back on, get them in there, screws, all right, this is turning out better, so just get that a little bit tightened down, get this other screw a little bit tightened down, this is one of the screws that probably was put in with a very thin screwdriver, get the other bushing, and get the easy screw in, and now the difficult screw, I assume they had magnetic screwdrivers back then, or maybe they didn't, who knows, surely they knew, surely they had magnetic bits, it would be nice to know if there were a patent on magnetic bits so that we could sort of date the the tools that they would have used to put this together, we've already dated Phillips screws, so we know that's why they didn't actually use them on this, I have a love-hate relationship with Phillips head screws, because they're designed to torque out, and when they torque out they damage the slots, which is kind of a stupid thing to do, so all right let's see if this actually works now, so what we want to do is we want to make sure that these two things go up in phase, yes, yes that is what we wanted, all right, so we're getting a little bit of friction somewhere, and it seems to be caused by this cam over here, let me put some oil on there, let's put some oil on the cam surface, rotate this, let's pull this down, and here let's just put some oil on the surface right here, and then try to distribute the oil in there, wind it lock up, okay it's this uh this um pawl back here that locked it up, I'm not sure why, and it's still locking it up, what happened, unless it's okay, so all right, so it appears to actually take some force to uh to get this um this thing rotating, see when it pushes down it actually requires some force, so that's not very good, but I guess if you've got a crank handle, so you've got some mechanical advantage, that's okay, it's um not as smooth as I'd like, let me see uh the other side, rotate, and in the other direction, yeah, yeah the other cam surface seems to be okay, um let me just uh put some oil on that as well, all right, so that's where we are, let's just leave it at that, seems to be working okay, so the thing about the selector gears is that if I push this in like this right, let's see, I'm going to select a couple of uh couple of teeth, so that's why it's called the selector gear, all right, it's a neutral position, now let us talk about um this lever right over here, so that lever pops right onto here, so what I'm going to do is I'm going to rotate this a little bit, and then lift this, so this is a lock right, so you can see, you can definitely see that when this lever is attached to this pin, this is not going to move unless this is rotated back, and then it can just rotate round and round and round and round until it locks into place, so that's an interesting mechanism and we're going to have to find out what actually activates that mechanism, so in the meantime I'm just going to force this over that, and then I said I was going to try to find a clip for this, so you know rather than using this little piece of wire, which I can do, but I'd really rather not, so let's see what I can find, all right, and I don't have any C-clips that match this diameter, I guess that should probably be next on my list of things to buy, a set of relatively small things like that, so I'm just going to put this wire back on and just sort of squeeze it and hope that it remains in place, I probably mentioned this earlier, but I think that what this could be, there we go, now it's closed, it could be a piece of spring wire, oh wait a minute, that's odd, obviously I'm missing a piece, great, all right, let's take it off, there's a piece that's supposed to go on here, oh you know what I think it is, I think it was that, I think it was that washer that I thought was a stupid washer, and it turns out to be not so stupid after all, okay, let's go get that washer and put it on, okay, all right, well I still insist, I still maintain that it's always a good idea to put a washer between the nut and the frame, so I think that those washers were a good idea, so let's just go ahead and stick this back on, okay, well that's what it was, oops, all right, let's go put some oil on this because it's rotational, put some oil all through it, and let's rotate it to distribute the oil, I'm going to keep this lever unlocked and rotate this in the right direction, and there we go, now if I release this, that's going to lock into place and it will simply stop, if this wire were in place, what would happen, nothing, so I still don't know what purpose that wire serves, all right, so let's see what we have left in our bag, so we've got a bell, a hammer, a this thing, a big screw, which doesn't go there, that's the purpose of this small screw, and then we have this large bushing that will probably go on there, and then we have this washer with shoulder that will probably end up going on there, so let's see how all of these pieces get put back on here, and it looks like the first thing that happens is I put this bell back on, now you can see that it's got sort of these indentations, which means that that's I guess just a way of preventing the bell from rotating because it fits on the slot, so it would go on here somehow, well here I'm just going to take the screw, let me put some oil in the threads so I don't get any rust, and let me go ahead and take the screw and just put it on there, let me see where I am, there we go, so now when I screw this on you can see that it actually doesn't rotate, that's kind of interesting, I don't know that they'd actually pay attention to that detail nowadays, they would just let the bell rotate, and you can see that this is the lever that prevents the bell from ringing, so that rings and that's the bell mute, so that's how the muting mechanism works, so there's this lever down here, okay, next parts, we are now incidentally in reversing in video three, so we're getting really close to the beginning, which is kind of exciting and weird at the same time, because you can see that the frame is all taken apart, there's still a lot of parts to go, so clearly those first three videos had a lot of stuff in it, so all of these pieces go together basically like this, we have this lever facing this way and this bushing is going to go in the back like that, okay, we've got this bushing which will actually sit over here like that, this mechanism I believe goes like this and it will fit onto there and then the screw will go through all of these parts like that, okay, so I think I guess that sits on there and this will probably end up I believe going into this hole right over there, because these gears will actually, see, that's how that clapper works, so these gears actually go onto here, so let's go ahead and, okay, and there is a little guide, there's a little guide right over here which I believe is for this, so this would go in like that and let's see, how am I going to, okay, I guess I just screw this in, oh, forgot to put some oil on there, okay, and maybe I should just put some oil in between here, because these will rotate and let me just take the thing apart again and just put some oil on here and I can put this back on, put this back on, great, now everything's coated in oil and let's see, so I want this to be like that, so now this goes up like this and I think that there's a little tiny little tab here and I think this might go above that tab, so let me unscrew this, loosen this, and raise that above the tab, is that how that works? No, I don't think so, unless I have this wrong, that's entirely possible, all right, so I have determined that that's the way that works, okay, so if I go ahead and tighten this up, so I'm kind of wondering what exactly goes here, because it's certainly not these gears and there doesn't appear to be a cam surface, so I'm guessing that there's going to be something rotational over here that will cause that bell to ring, so let me go ahead and tighten that up, maybe I should put the bell mute on so that we're not ringing the bell all the time, okay, so and then we've got some springs here, so we need to determine where the springs go, because this is obviously going to be spring loaded, as I suppose will this lever right here, so I'm guessing that this spring will go on this post, and I'm guessing that so will this, okay, and where do these springs go, they all go on this post right over here, so we can go ahead and try to try to take the end here and put it around, I think probably this will end up going on here, and this will go on the interior of the post, so yeah, so let me actually take that outside one off and take this one, the reason that I say that this goes on the inside is because it seems thinner to me, so let's see, take that off, I claim that this goes around the post like that, is it on? Not quite, there now it's on, and then I take the other one and just put it around the post, there we go, so see I'm moving this and it's not touching this spring, and yet all the springs are working, okay, mute the bell, so the next part, now that we've got all of these done very nicely and oiled and all in place, the next thing is we're going to play with these selectors again, so the way the selectors basically work is, I have some, let's see, I have these, all right, so these are the two different kinds of, I think they're called bails, and you can see that they've got holes here and here, and that basically means that they go between this and here, and they swivel like this, and they swivel in pairs basically, kind of like this, and one basically fits here, and the other basically fits here, so that they can, if I can put this on a pin, it'll be easier to show, put this on the next pin, all right, so basically as the keys go down, put that in, there, here, so as the keys go down, they will push this in varying amounts, so you can see that these tabs are bent more, less, less, and less, and these tabs are all bent in the same way, because this is just five, so just like this, it's zero, and then if I push this just a little bit of the way, it's one, if I push it a little more, it's two, a little more, it's three, and all the way it's four, then I don't push it at all, and I push this, and that's five, and I push this a little bit, and that's six, seven, eight, nine, so in that way, you can select anywhere between zero and nine teeth, okay, and that's the purpose of the keyboard, the keyboard pushes against this, and thus rotates these bales, so the next step is actually putting all these bales on, and I've got a whole bunch of them here, which I believe have already been washed clean, because they were really dirty, and the reason that they were all really dirty and greasy is that the keys rub against them, so I guess the first thing that I'm going to do is I'm going to put some oil on the pins, all of the pins, that seems like a good idea, okay, and the pins here as well, now, so I know that these are the fives, so I'm just going to install those first, just to be maybe regular about it, now am I making a mistake by doing that, let's see, let me take one of the ones, the units, and insert it, didn't seem too difficult, let me try the next one, yeah I'll just go, I'll just do one, then five, then one, then five, so, and the key is that you want this movement to be smooth, because if it isn't smooth, then the key is going to have a very hard time, let's see, this one goes here, that goes in there, it's hard to get the pin in place for some reason, because, ah, there we go, okay, now I need a five, and another one, now because the selector gears actually rotate against this, you can see that there is a wear over here, so that's another place that I should put some oil on, so one, and five, it doesn't matter, it doesn't matter which five is which, they're all the same, as long as they alternate, actually this one goes in that pin fine, but it doesn't actually go in this one very well, and that's really odd, let me set that one aside, and try this one, that one's difficult too, maybe I'm gonna, I don't know if it's a problem with these bales, whether they're bent slightly, let's see, let's try this one, that goes in very well, all right, so those will have to be inspected, and five, one, and five, oops, that's a one, this is a five, that works, all right, one, and the last five, okay, there we go, just like that, so what I need to do is put some oil on this surface, these surfaces here, so I'm just going to smear some oil on, because when the selector gears start to rotate, they're going to rub against these bales, so now when I rotate, I rotate the opposite way, oops, I have to unlock this guy, don't I, all right, so those are the bales, that was easy enough, and then in order to prevent the bales from lifting up, there is a plate that goes right on top of here, so let me, where is that plate, was it in a bag, no, it was not in a bag, is it here, no, where did I put that thing, it is in a bag, it's in bag three, so we're on bag three now, how exciting, so this is the holder for the bale, and it has this sort of a bent profile, and of course the reason is that it goes flat on the plate and then goes down in order to hold the bales in place, that way they don't come up, so let's see, we have in bag three a whole bunch of screws, as you can see, many of them, we've got four big screws, which of course don't fit in there, we've got a whole bunch of screws that have green paint on them, so that obviously came from the cover, so I'm going to separate those out, and I think, yeah, so we basically have, and these are all the same size screws, so here are two screws without any paint, and they of course go here, so let's go ahead and put some oil in there, and I'll use the tiny screwdriver, actually no, I'll use the magnetic screwdriver, and this is why I didn't want to use the magnetic screwdriver, so I'm just going to put this in with a little bit of finger rotation, same thing here, a little bit of finger rotation, now I can go ahead and take the screwdriver and screw it in, I need a smaller bit, there we go, now these bales aren't coming out, and now the exciting part is, at least I think it's exciting, is that we get to put the keyboard back on, so the keyboard goes on, I believe it's probably this way, no, it's going to be this way, because the reason that it's going to be this way, I believe, is that these little U-shaped indents here and here are for the carriage moving mechanism, that little thing over here, and it's always on this side, so the other thing that I'm going to do, now they use grease to grease this up, I'm going to use oil, because that's just me, and I don't like to use grease, because grease will just attract dust, and the dust just stays in the grease, because that's what grease does, so that's why I'm using oil, that didn't take too long, so this has to go on here, so you can see that there are these screw holes on the side, there are actually four of them that correspond to these large four screws, they go in here, here, here, and here, so we just position this carefully, frame, there we go, so it just slides right in, just like that, it aligns, and then we're going to go ahead and I'm going to coat the thread of the screw, and I'm going to put one in here, and get it aligned with its hole, see where is it, is this it, I think that's it, all right, now I'm going to do the same on this other side, I'm going to put some oil on the threads, put it in the hole and get it aligned, okay, that way I know that now this axis is correct, so the only thing that I need to do is just rotate in order to get this, get this correct, and now the other side, nope, that is not correct, is it, or is it, no that is correct, all right, what's throwing the off is that there's this other hole over here, and then I look over here and I see that there's like one hole on top of the other and the top one is populated, so therefore it must be the bottom one, but in fact this bottom one lines up with this top one over here, so that hole must lead to something else, okay, so now that I've got them all in, I can just tighten the keyboard up, I need a bigger bit this time, so here, okay the machine is getting quite heavy now, the machine is getting heavy and exciting, because things are now coming together, okay, so let's just, I'd like to make sure that the keys are actually working properly, so let me go and hit a nine down here, and indeed we can see that back here these gears have stuck together, and if I start to rotate them hopefully it'll turn, unlock it, turn nine positions, one, two, three, four, five, six, seven, eight, nine, good, now I can clear it, and maybe hit the eight, this is actually the 3D printed one, so this will be interesting, one, two, three, well that was unexpected, let's try the seven, three, four, five, six, seven, all right, well that's sort of useful to know, let's just try the eight again, I suspect what happened is that the five wasn't activated properly, let's try again, one, two, three, four, five, six, seven, eight, yeah that's correct, okay, why wasn't the five activated properly, because this is not, because when I press down a key, right, this thing can still move back and forth, and you can see the the gear is back here moving, right, so there's actually a plate that goes on here, so once I put the plate on I'm pretty sure that all of these keys will be lined up properly, they will move up and down only and not left to right, side to side, but yeah that does seem to work, so there we go, the keyboard is now in place, let's lift the camera and get a bigger view of the calculator, so there's a larger view, everything looks really nice and clean and spiffy, so let's see, I believe that the next thing is actually going to be the cover because I've got a ton of green painted screws, so the cover would go on, I'm going to have to clean the cover a little bit, make sure that all these pieces are oiled properly, and I am also going to have to figure out how to put this carriage lifting mechanism back on, oh there's the label for bell on or off, that is for this, so that's kind of nice, and there is actually, you can see that that lever actually apparently might move this lachy thing, and where does this lachy thing go? It seems to go somewhere over here, somewhere around here, so that's an interesting mystery that we'll try to solve, there's also this item count lever, and basically all that does is it locks the one key over here into place, so that allows you to use this register for sort of like a separate register than this side, and then we've got this thing, and I'm not really sure what that's supposed to do, so that'll be interesting to find out, so I believe we probably have just one more video to go before this entire thing is complete, so hopefully everything will work properly with the exception of this broken piece, which we can pretty much fix later because we have seen how easy it is to put this back together again, so until next time, hopefully for the last time on the K, Rob saying see ya!