Adam Savage's One Day Builds: Machining a Gear!

hey everybody uh Adam Savage in my cave with a toy this right here this is a uh it's a flywheel car like uh we all had as children uh I love these things and I have this desire to make one really really big this actually this started as an idea for uh back when Jamie and I were touring a science show around the world uh between 2012 and 2016. uh and I wanted I saw it and I sought a certain kind of gag uh specifically uh I wanted to build one of these so heavy that like we could bring it up on stage and start it and like someone couldn't stop it there are problems with doing something like that on stage there are you know cascading sets of potential issues with such a thing but I couldn't get out of my head this idea of a really heavy flywheel driven car um and so I uh I uh I took a careful look at this guy uh and I looked at the gear train and I noted that there were four gears in the gear train one two three four and a flywheel and that they were directly uh driving one set of wheels um and see here the wheels as they are are yes uh the first gear in the train is 36 teeth the second is 12 the third is 46 teeth and the fourth is eight teeth that's this last uh pinion gear here uh that drives the flywheel now I I went online and I was able to find Wheels one and three uh 36 and 46 teeth respectively but I was unable to locate a 12 and 8 tooth gear of the same pitch These Are diametral Pitch 12 with a 14 and a half degree pressure angle um die just briefly about what some of that kind of means and I'm a good person to explain it because I only kind of understand it so I'm gonna give you my somewhat understanding of gear teeth and their geometry so understand that gears are basically uh individual radio levers doing their work on each other uh and um if you want the maximal transfer of energy you want geared teeth that are always engaged that means that there is always two surfaces touching on those gear teeth if they are not touching you end up with gears that rattle like that and those are fine there are lots of gears in the world set up with tolerances that they can actually move a little bit but the goal the best transfer of energy occurs when the geometry of each gear is such that the teeth Interlink in this really um and this really hold on I got to see there there we go so like you know you can go read papers about these sliding geometries and how they act where the pressure angles are and all of that stuff you don't really need to know all of that I've got two gears here that are dimensional pitch 12. that's a known quantity with a 14 and a half degree pressure angle and when I know those two things I can buy a set of gear Cutters that are pre-shaped to create the proper geometry of the teeth and a full set of gear Cutters looks like this now to the uh to the immediate glance this looks like these are eight of the same thing but in fact actually there's a really fascinating reason there are eight of these because um you use a different one depending on how many teeth you have radially around your thing so what I'm about to do is I'm about to go online actually I think I even have I should find it in here it should it would be it is in here I know it's in here uh I could go online and look up a gear calculator I'm sure but I think I'm gonna go through the exercise right now trying to find the information I need here and the information is you take a dp12 gear with a 14.5 degree pressure angle and you say I want eight teeth and what it will tell you is what is the outer diameter of that piece of metal you've got to turn and how deep do you cut those teeth once I have those numbers for both the 8 and 12 tooth gears then I am going to break out my uh dividing head rotary table and I'm going to cut those teeth with the proper gear cutting I've never done this before I have never done this before I this is like um my first car was Volvo station wagon and when you're first learning how to repair a car you do the first repairs the first repairs you do are surpassically simple you you learn how to change your tires you learn how to tighten opposing bolts on your tires you learn where to put the Jack right this is all very basic knowledge but when you're first learning how to do cars when someone says bleeding the brakes like none of those words mean anything to you when you first start working on a car because you don't know the brake system's Under Pressure that it's hydraulic in nature and that you want to get air out of it and the air gathers in certain places and when you refill it or you re-plum it you need to actually do this process at the beginning of car repair all of that is just this mystery it's all like yeah it's engineering speak but then as you go through so in my progression with the Volvo I started out replacing the tires and then uh I had a thermostat go bad that's a very easy repair in a Volvo 245 DL station wagon so I replaced the thermostat my car worked much better um I was only firing on four cylinders at one point on three cylinders at one point the car was still run I was able to figure out which of the spark plugs was bad and replace it later on what was the what was the uh oh right yeah my drive shaft I had a problem with the U-joint in my drive shaft and I actually pulled the whole drive shaft out of the car which was was much simpler than I thought it was and I swapped out two U-joints um there used to be this place in Berkeley called rpr discount Volvo parts they might still be there they were like across the street from the hotsy-totsi on on San Pablo anyway uh they would like lend you tools if you were swapping out your shocks they would send they would lend you the compression tools for that it was a terrific Place uh I did so much car repair on that Volvo so I guess what I mean to say is when one is starting out in a discipline there are all these levels that from the big from the vantage point you are currently at there are levels that seem impossible and for the longest time for me as a machinist the idea of actually cutting cutting gear teeth even though I sit there and I watch click spring all the time the idea of cutting your teeth that actually worked and looking up the charts and making it work just seemed like that was something for smarter people than me but frankly yeah I know you didn't expect me to come in with a giant sidearm um frankly going through the exercise of making the Samaritan uh in the summer of 2020 it demystified a lot of Machining for me um and part of the demystification was realizing how everyone kind of finds their way to the ways in which they solve engineering problems uh and you know the the the learning of a new skill for me is always sort of like wrapping my head around different scales of precision and different outcomes based on my knowledge at the time and so now I feel uh like I am qualified enough to cut a couple of Gears I actually have enough gear I have two of each of these gears so I could build two of these cars if I wanted to but I only have one set of tires all right and I have a big beautiful oh look at this flywheel this big chunk of cast iron I'm really psyched about this I want to put this on the street and I want it to go for like a block um so I may not get to build this whole car in this video we're going to see how I go it may be that this video is simply me cutting to uh cutting a couple of eight teeth and 12 teeth gears um we're gonna see how we go today um um [Music] I'm going to look in the index under gears ears gee gearing gear Cutters formed number for bevel gears involute form [Music] I dog geared the page I've been here before I don't remember being here before [Music] well it would seem that with a pitch of 12 a 14 and a half degree pressure angle that the smallest number of teeth I can cut is 10. which is fine just slightly reduces the ratio but that's not as big a deal and I could I guess if I wanted to cut a bigger gear than 46 teeth for this but I'm gonna cut the first one out so here's the list of of uh wheels that I have gear number one is 36 two is twelve three is 46 and 4 is 8. um what I think I can do here is do both number two and four at ten foreign [Music] all right I looked it up uh it turns out it's a one inch chunk of stock and I have this big beautiful piece of bronze that I cut from a propeller shaft on a boat on MythBusters low many years in the past it looks like I'm using a number one cutter for 10 teeth out of this I'm going to machine it down to a uh one inch diameter and I'm actually going to be cutting this uh the long way I'm going to be cutting all the gears I'm going to be cutting four 10 tooth gears at once and the way I'll deal with that is I will um I will machine this down I will machine a through hole I will then tuck this into my dividing head I just trimmed up my Vise and I got to pull it off again it's fine it only takes a few minutes but I'll I'm gonna end up using my dividing head and a um an adjustable tail stock I had to look up the name of it it's written on my machine thing over there okay to the lathe to the lathe Boy Wonder [Music] I'm gonna pull out the uh the drill chuck and put in a live Center then I'm gonna crack this bring this out and I'm going to nail this whole thing down [Music] I think this is probably one two five you know what it is exactly one two five look at that all right so I want to touch it off [Music] beautiful look at that the jewelry bronze Cuts really pretty doesn't it foreign [Music] yeah yeah I took out 30 thou all right so I want to take out 220 thou so let's try a hundred [Music] looking good air is the reasonable way to remove heat from a machining equation and it smokes less than the uh than the cutting oil bronze Cuts hot I always think the brown seems to cut quite hot oh I just love it what a what I love is that it was 220 thousandths and I took off 200 000 according to the dro and I ended up with exactly twenty thousands over one inch and I just like it when the dials all agree with each other it is a sweet sweet business so we're gonna bring this back over here we're gonna dial this in 20 more thousands hmm look at that so uh when you cut metal and you end up with uh the little chips that come out of it like this this is called swarf s-w-a-r-f and uh not a great word and I'm here to tell you that I think that bronze swarf wins as the most beautiful of all swarfs look look at how pretty it's like golden treasure uh man that is that's a hairstyle right there uh I'm gonna clean that up and look it's almost like you could name it I love the bronze swarf and now uh the bronze shaft here is exactly one inch this is an intellectual exercise if I'm off a few doubt it's not that big a deal but let us great okay now that's I'm gonna try out my mini for you laughs I am two thousandths over 100 1.0020 that's great I am I'm pleased that is good enough for me to start cutting [Music] foreign rearrange the bed of my Mill to cut some gears it's going to take a few minutes I literally trimmed this in yesterday got it to like really nice and precision uh tramming is just the process of making sure that the Vise is uh perpendicular and perfectly Square to the mill on all three axes foreign best practice on a mill is each time you remove the Vise or reinstall something new on the table just used an India just use an India Stone to make sure you don't have any dents or high spots [Music] foreign [Music] yeah that'll do it three blocks Tinker Toys it's all Tinker Toys uh uh uh uh oh oh I have an idea I have an idea it's forming in my little brain oh right the question is is the team will work foreign [Music] that's close enough I'm gonna let that stand sharpening so uh first up I want to determine that it is in line this way so I bring it in foreign [Music] not so bad [Music] all right as I spin this thing [Music] foreign s out of round which means a total of about four it's a sheet of paper I want to get a little bit better so I'm gonna try that [Music] foreign [Music] all right one thou out I'm gonna call it we're gonna tighten it down so let's bring this in and we'll take a look foreign [Music] these gear cutting wheels are meant to go on Arbors that hold them that look like this this is the arbor for these gear cutting wheels and I did not check to make sure I had one to fit the whole size of these and I don't however I can utilize one of these nice sound um so I took one of I had two of this midsize and I took one of the Rings and I turned it down stepped it down so that it fits the gear cutter I have and I even machined in a little uh keyway slot so I'm gonna clean this up and uh clean this up [Music] the file and uh okay so the way I've done this is um yeah see that so I'm just gonna machine a little bit of Steel that wedgie poos in there and then gets captured by the top capture nut like that and I have cobbled together a gear cutter with the Arbors that I have uh right so that goes like that look at that yeah I'm digging it it's a half hour I didn't expect all right it's not pretty but I've jammed a little bit of uh material in there and that should hold on to it so now I registered this and this thing can't move so I'll put that guy on there and that should be yeah there's my gear cutter so this is an R8 collet this will enter the mill and then this will be cutting Dougies [Music] all right so if uh let me just do a diagram here yeah okay so 320 000. the top Edge is in line with this that means the center of the gear cut is 160 thou below the top so I want to move this 160 thou less than one half of an inch or I could come up 160 thou yes could come up 160 000. one sixty zero it [Music] and then come down a half inch there we go I'd let the machine do the math for me locked okay so now the gear is in the center of the post [Music] [Music] foreign [Music] [Music] foreign [Music] [Applause] [Music] I think that's it I think I just cut my first pinion [Music] it rolls I don't know it always seems a lot quieter when Chris at glitch Springs cutting gears well it doesn't seem like that [Music] I may have been exaggerated none of these really moved so I think I can start to undo this stuff I can pop that can undo this oh come on let's stay on oh come on now yeah I think I definitely need a new number one cutter it's a respectable looking opinion if I Sizzle myself let's cut it into a couple of useful gears and see if we can't 2 30. I might be able to depth these four wheels together today it's not the prettiest of gears ladies and germs it's a gear it feels pretty good the tiniest foot rough around the edges I'm in I'm insane if I thought I was going to get to depth in this I'm still not even sure there's two now there's one stack one stack and then one of these goes through the flywheel yeah um [Music] I think this is a great place to stop I know I still have to do some cleanup on that and make those faces actually I'll do that there it is it might not look like much but it's been a long dinner I need to get here uh and I'm including most of my life up until now um my first gear baby's first gear very excited a respectable looking opinion give or take just wonder if it won't get a smooth I can't tell you how happy I am about this I know those could look better that's another video uh thank you guys so much for joining me on this uh specific Journey the shop is so nice and clean you guys have a good weekend I'm assuming you're watching this on Friday just because I happen to be filming it on a Friday

Channel: Adam Savage’s Tested

Views: 239,298

Keywords: tested, adam savage, one day builds, one day build, adam savage one day build, adam savage tested, tested adam savage one day build, tested adam savage, adam savage builds, machining, gear, flywheel, flywheel gear, build, lathe, mill, clickspring, adam savage machinist, how to machine a gear, how to machine something, how to make a gear, how to handmake a gear, homemade metal gears, how to make a toy car, adam savage toy car, adam savage milling machine, adam savage clickspring

Id: bXFRBQNQBQM

Length: 29min 26sec (1766 seconds)

Published: Wed Dec 07 2022