 Hello, welcome to part 13 of disassembling a Monro calculator. Sorry about the audio levels from last time. My audio recorder did not record my fault, but now it should be working fine. So when last we left, I was going to look at these pins at the end to see if I could take them out. I'm actually thinking that they are permanent. The reason that I say so is that I looked at them under a microscope and you may be able to see that there are these marks maybe on the sides of these pins here and here. And let's go to the other side. And well, there are these sort of semicircular marks over here. And what I suspect that is is that they had a tool, maybe something like this, and they used it to bang the pin into the hole, which presumably was slightly undersized. So these are basically interference fits, which means that the pin is slightly larger than the hole, which is meant for absolutely permanent fixtures. So I'm suspecting that this is absolutely permanent. So what does that mean for cleaning this up? Because as I said, this wheel right over here feels really sticky. And it would be nice to sort of clean this. Well, you know, what I could do is I could just take some cleaning fluid and just dunk it in. Luckily there aren't any bearings in here. This wheel also is kind of sticky, but it does come out, so I can actually clean that up. So I can probably go ahead and clean this whole thing up with cleaning fluid. So I think we're going to leave this like that. Really the only thing that I wanted to show on the Leibniz wheel is exactly how it worked. So we can see that, and I probably went over this before, but we may as well just go over it again. We have one section which has five teeth on it, and another section which has four teeth on it at different depths. So the idea is that there are these two sort of surfaces which push the, I'll call this the five wheel, either leaves the five wheel in this position or pushes it over into this position. And we have another thing, surface, which pushes the unit's wheel over either zero, one unit, two units, three units, or four units. And the idea is that if the five gets in line that way, then you can push this over and make six teeth or push it over again and make seven teeth, eight teeth, and when they're fully together, that's nine teeth. So that when you rotate, you get a varying number of teeth that engages the intermediate gear. So that's basically how that works. So it's important for these things to spring back, of course. And again, these are all kind of sticky. This one seems to work pretty well, but this one is still a little sticky. And the easier these are to push, the better the keyboard will work and the better they go back, the less stuck digits you'll get. So I really want to clean that up. Luckily, there are no bearings on here, which I said earlier. The problem with especially sealed bearings is that when you clean them, you also clean out the lubricant in them, and then the bearings don't actually work anymore. So we're going to leave this as is. There really isn't that much to it anymore. So the next thing that we're going to do is take a look at the carry section. So this is the carry axle. It's got, I don't know why they call them dogs, but these are called dogs and they're spring loaded. And the idea, again, we went over this before, is that as this thing turns, if a carry is needed, there's a lever that pushes this carry dog in. And then as it rotates, it will turn the digit gear one. And then the next, I guess maybe this thing, will reset that lever so that as it keeps turning, the carry is no longer set. These are fixed gears here at the end. I'm not sure what this is for, and I'm not sure what this is for, and it seems to be spring loaded as well. Unfortunately, these two, this gear and this cam surface over here, this is a cam surface. There we go. You can see the different radius over there. These are also held in by taper pins. Given the adventure that we had before with taper pins, I'm just going to leave these on. The other end, luckily, is not held on by a taper pin. It is, in fact, held on by a special kind of a nut. So we can see, hopefully, that I can just take this, and while I can't rotate, that's what this tool, I think, may be good for. The idea is that I made this opening so that it just fits here. Let's see. There we go. So I can just hold on to it with this, and turn this other side, hopefully, without bending anything. That would be tightening it, wouldn't it? So I need to loosen it like this. I don't want to wreck the spring. Maybe what I'll do is I'll put this here, maybe. That's what I work. Ow! Okay, that's not working. I may need a bigger lever here. So, okay. Through the magic of editing, I will go and get a bigger wrench. All right, hello. I have a bigger wrench. A bigger wrench. So we were going to try to remove this nut from the end. So let's see what I can do here. Tighten the wrench. There we go. All right, sometimes all you need is a bigger tool. So I can remove this nice little holder that I made. How big is this? You may ask. Well, this round stuff here measures out to about 0.696 or so, and this I made 0.75. So there's your answer, three-quarters of an inch. Actually, it's slightly bigger than three-quarters of an inch because I went and smoothed the inside. So it fits loosely, which is good. And it also makes a nice sort of tuning fork sound. Okay, so I can just remove that. Flat spots in the front. So I'm going to start a new bag. I think we're on 14 now. So the good news is that once we take this apart, the only thing that's left to take apart is the carriage. The carriage has something wrong with it. If you rotate it, let me just reset this thing. So if you look at the top series of digits, if I rotate it like this, you can see that the top register zeroes properly. The same thing is supposed to happen with the bottom register, but it gets stuck. So that's one thing that we're going to have to look at. The other thing is the digit wheels. This is really smooth, smooth, smooth, smooth. Oh, this is really stuck. Sort of smooth, stuck, sort of smooth. So obviously that needs to be fixed. So we have smooth, stuck, stuck, smooth. So these digit wheels obviously need a really good cleaning. So we will attempt to do that. I'm not sure how successful we'll be considering that. There are many, many taper pins in here, but we'll take apart what we can and see. Back to the carry mechanism. We've just taken this nut off. So now we are going to take a pen and label bag 14 of 77339. I think that's right. Yeah, and stash it in the bag. So I may not take apart the whole thing. I just want to show you some interesting features. Here is a washer looking thing, but it has a notch cut out in the end. And the notch is there because this axle has a keyway and a key in it. The key prevents all of these parts from rotating. So I'm going to put this in bag 14 and now we can remove this end piece. And I'm only going to remove the one end piece because once you remove one end piece, the other end pieces are pretty much the same except they're more spread apart. So there's the end piece. It is not symmetrical because as you can see, there is a hole on this side and not one on this side. So it goes on like this and not like this. Okay, here's a dog. I can pull it out. Let me pull out the other one. It seems easier. It's attached with a spring and basically it just fits in there. So that's really all I'm going to do. Oh yeah, and then there's a spacer. The spacer is basically just a brass washer with a piece cut out of it to fit in the keyway and there's the key right over there. So let's go put that back because really, there's not much of a point in taking this apart. There aren't any moving parts on here except for the dogs. Everything else is just a spacer. So this thing is really, really easy to clean and a bit of a pain to put together again. So let's see. Remember to angle all of these pieces so that the camera can see it. So I put this back together again. It's just being a little bit of a pain. Okay, that's because the second part is together. First part is almost together. So I guess I didn't really need that 14. So I should go on the keyway and not rotate. Good and then the next part is the nut which goes on the threads and now we need to tighten it up. So I'm going to put my special tool in here to hold on to it and then I'm going to tighten the nut. Okay, that's all I need. Make sure the dogs work. This one doesn't work because it's a bit loose. Let me check the other side. Tighten this up again just a little bit just in case. Yeah, okay. So that's the carry mechanism. As to why there is a cam surface over here and why there is a gear here that seems to have a piece cut out of it and what this thing is for and what this thing is for, we'll find out when we put this thing back together again. So all right, that was the carry mechanism. So now that we're done with the carry mechanism, let us go to the final piece of the calculator, the carriage. When we're done with the carriage, the next thing that we're going to do is we're going to put all the pieces back together, cleaning them as we go along and lubricating them. So and then hopefully the entire thing should work. So all right, let's take a look at this. So there's a whole bunch of cams here and other things. It's kind of difficult to describe exactly how this works. But in fact, it's really difficult to describe how this works. And hopefully we'll figure out why this thing isn't turning. Well, let's see if we can figure it out. Okay, so I'm pulling on a stop. Okay, that doesn't seem to do it. And in fact, it doesn't seem to be anything on this side that is causing the problem. And I'm moving the parts on this end and it doesn't seem like there's anything stopping this from moving. So I believe it is maybe, maybe it's this middle piece that is preventing it from moving. So we'll take it apart and find out what's going on. Okay, so first thing that I'm going to do is I'm going to take off the handle. So we'll start a bag, we'll use a bag 14. So I'm going to take the handle off first and there's just a screw on the end that I can remove. And this brings me to something interesting about these machines. Let me measure this, this guy first. This is a, is it going to be an 836? It is going to be an 836. And its length is 0.283 bag 14. Okay, so the thing about these handles is that when you buy them off of eBay, typically what the people who are selling it are going to do is they're going to shove it in a box. And the box is probably going to, and the machine is probably going to end up sitting like this. And in fact, it's going to be sitting on this crank and the crank will actually bend inwards. I've seen that on many of these machines and the solution is to just ask them to unscrew that screw and then remove the crank. It should just come right off just like that. Just ask them to do that, put the screw back here so that it doesn't get loose and then ask them to stick this in a bag or something. Same thing with the main crank handle. As we saw, there was a little lever that you could pull and then the crank would just come right off. Ask them to do that so that you don't get these damaged. Okay, so I'm just going to put this... Should we take this apart? You know, we could. So this thing, it has been chewed by a dog, it looks like. But it can be easily removed. Yes, it can be easily removed. If you have the right screw driver, it goes right off. That should have been all one piece. And we measure this to be... Looks like it's going to be number or 640. Yes indeed. It is 640 and it measures 0.245. So we'll stick it in bag 14. Now, I could probably model this and 3D print it in plastic. So that will replace that and this thing. So when you get it broken like that, that is a problem. Interestingly enough, I made a 3D model and I had it printed out out of stainless steel from Shapeways. And there is my model and it was printed out. And there is the original and they look identical. I made the hole on this slightly too small. But it nevertheless, it's still functional. It will still go on. It will still go on just like that. It will still crank. So I would say that this is perfectly functional. The only thing it's missing are the threads in here for the screw. Other than that, the little plastic piece does fit perfectly on. So that's pretty nice. Unfortunately, this cost I think about $30 to do. But if it's a choice between having a bent crank that doesn't actually work and a new crank which does actually work, I would use the new crank. Although $30 is a significant portion of what you paid to get this on eBay. So maybe you want to try bending it back. The few that I tried bending back, one of them actually broke. So that was a pain. Okay, that's bag 14. Okay, so let's see what else we have to take apart. Okay, so there are essentially, effectively, three shafts. Well, four shafts it looks like. One here, one just below it. So one here, one just below it. One top one over here and then this one. So we can't take this one, these wheels out, without taking this one over here. So we're going to try, let me see. Oh, I see taper pins. Oh, I hate taper pins so much. I hate them so much. So I'm not sure I even want to take the top one out. Well, let's see what we can do. Okay, so all right, take a close look at these screws. You can see that there's a sort of inner screw. If you turn it over, you can see that there are inner screws here. Those inner screws are actually adjustment screws. They adjust the shafts back and forth because it's important to get these gears in line. There's a lot of styrofoam in here for some reason. Styrofoam could be a reason that this is failing. So it is important to take this apart and make sure that there is no styrofoam in there. So yeah, so the adjustment screws. They move the shafts back and forth to get them properly aligned. So obviously when we take this apart, we are going to have to figure out how to get that alignment. Correct. So what we're going to do is let me see. How should we proceed? I think we might be able to remove this top shaft first. So let's go ahead and try that. Now in order to do that, the first thing that I'm going to do is remove the adjustment screws. So I'm going to need a smaller screwdriver. I think this one is good. Yeah, this one is a good size. So I'm just going to unscrew this. It's kind of tight, but I guess that's okay. You sort of want adjustment screws to be pretty tight. Not so tight that you can't remove them. So sorry about the noise. This is a working wood machine shop. So okay, so this is a set screw. And we're just going to see what size it is. Looks like it's a quarter of an inch, but what is the size of the thread? Maybe it's not a quarter of an inch. Maybe it definitely is a quarter of an inch. So it's a quarter 28. Its size is 0.232. So I appear to have damaged the slot on this one. So I may just want to replace that with a set screw, a modern one. So that'll go in bag 14. I don't need to remove the other adjustment. Now you can see that the shaft actually moves back and forth. That's the effect of the adjustment. Okay, now we need to remove this. This is actually kind of a bolt, and the nut is on the other side. Now, so I would need to get in there with something really small. To remove that nut. This wrench isn't going to do it. So I'm going to try with these needle nose pliers to hold onto this. And then take a big screwdriver and just try to unscrew it. You know, that doesn't seem to be working. So what I'm going to have to do is try to find a smaller crescent wrench. Maybe that'll fit that. So I will be back. Okay, so I'm back. I have a 916 crescent wrench. For comparison, here is another 916 crescent wrench. However, if you look at the sizes, I have a very thin one. And apparently you need a thin one because it needs to fit right in here. And then you need to turn it. So I'm going to turn it. There we go, I think. Did that actually work or did it just slip off? It just slipped off. Okay, I need to turn this. So, well this is a really tight fit. I wonder how they did this. Maybe what I can do is I can take the thick one and just jam it in there. Oh, there it goes. Is it turning? Yeah, it is actually turning. Okay, so I just need to unscrew it then from the end. There we go. So I'm holding onto the nut and just unscrewing the end piece. Okay, so there is the end piece. It is basically a bolt with threads on the end, but it's also got a hole in the middle with threads. And this is actually too big to measure. So there we go. And I'm going to try to remove the nut. No. And that's not coming out because it's stuck on the end of the shaft. So the question is how do we get the shaft off? Well, there are these. There is this arm here which is attached to the shaft. And there is another arm here which is attached to the opposite shaft. These are basically stops. And they prevent the axle from rotating it. They don't prevent the wheels from rotating, but they do prevent the axle from rotating. When you rotate the axle, that zeroes out the wheels. So these in effect prevent zeroing. And they lift when the central crank is turned. So there. This thing lifts and now I can turn this. Well, almost all the way. And it's not this that's causing it. So anyway, what I need to do is remove the spring from the arms. So let me just take one of these. All right. Now the arm is basically free. And I can pull this out. So that's the one side, but it doesn't come all the way out. So we have to examine the other side now. So let's do that. So here's the other side. So I can lift the shaft, but can I pull on it? No. It looks like there's something in the way. So what's in the way? Well, certainly this central axis appears to be in the way. Yeah, I'm pretty sure. Yeah. So there's a cam surface here, which is being prevented from moving out that way by this piece of metal over here. And this piece of metal, this is about the only the extent of its movement. It actually seems like I should be able to move this even more. Here's another set of arms. Yeah. So when this is in the right position, this also seems to prevent the axle from moving. So it looks like there are two things in there. But nevertheless, this is still preventing this axle from moving. So it looks like I need to take out perhaps simultaneously this other central axle. So let's take a look at doing that. So first on the back, there are these two screws which hold in this support, which seems to support this central member. So I'm going to unscrew those. So there's one screw, 640, 253, bag, and the other one. I think it's probably going to be the same thing. It's 40, which if I could get my hands working properly. Rob's hands are not working properly. There we go, 640 and 254. So the same size. Okay. And now I should be able to just remove this somehow. Let's see. It seems quite difficult. I wonder why that is. Ah, because there is another screw holding it in. So let's remove that screw as well. Ah, there was a washer that came out from somewhere. Okay, so there's another screw. It is also 640 and is also about .25. We lift it and we see that we have the support and two washers. Apparently no third washer. Nope. Okay. So, and I think those two washers were from here. Okay, so. Oh, there are three washers. Okay, my bad. So there must be one washer per screw. Let's measure the outer diameter. .376 and the thickness is .012. So we have three washers and a support. The support went underneath somehow. Yeah, it somehow went underneath and it sort of hooked under here. So that'll be an interesting puzzle to figure out when we put it back together. Okay, so that's one end of the shaft. That's the middle of the shaft. Now, one end of the shaft appears to be just placed into this hole. The, it doesn't look like there's a screw or anything over there. So we should just be able to lift this out, at least a bit. So let's go ahead and do that. We've got, as we saw before, an adjustment screw and a bolt with another nut inside. So let's go ahead and take the adjustment screw out of the central one. Oops, I moved the camera. You know, I really don't need to remove that adjustment screw, I don't think. If I can just loosen the nut with something, well, that's really hard to get into. I don't see that I can get in there. Huh, maybe with needle nose pliers I can try it. Should I remove this side? Yeah, I've got to remove the central shaft, definitely. Okay, so let's see what else we can try to remove. Here's this thing, which I don't know what purpose that serves. It doesn't seem to lock or anything. I don't know, maybe it just makes it harder to turn. I don't know. Let's see, okay, there's an arm here. Well, let's just attempt to turn this side. The problem with doing that is that it is, I just don't have a lot of torque. Yeah, that's not going to be a good idea. I have to remove the nut somehow. All right, so it's coming up on 47 minutes or so, minus the editing time, so maybe about 40 minutes. So we'll end it here. In the meantime, I'm going to try to figure out what I can do to remove this nut. And we'll be back later. Bye.