Internal Splines (and Hexes Too)

This is probably the most complicated part I've machined. A friend asked if I could make a shaft coupler that had an internal hex on one end, and an internal involute spline on the other. Since I have a metal shaper, I said I should be able to do that... Of course, I used every other machine in the shop in the process. I ended up cutting the spline on the shaper, but made a broach for the hex end, following the method shown by Clickspring in this video: • Spare Parts #13 - Maki...
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/ jeremymakesthings

[@JeremyMakesThings]

A couple things keep coming up in the comments, so I figured I would address them here: In getting ready for this, I was able to find the pats diagram for the pump, it shows a one-piece, rigid coupler attached to the shaft. In fact, the shaft and coupler are listed as one part number. It’s not a lovejoy or other sort of flexible coupler. And yes, the fit on the spline as shown is probably a little tighter than it should be, but after several rounds of assembly and disassembly, the fit did loosen up a bit. I’m assuming there are some small burrs in there that got knocked down. If I had to do it over again, I probably would make take another .001 off. Additionally, the hex shaft is about .003” under the nominal dimension, and I made the broach to the nominal dimension, so there’s some wiggle on the connection on the hex end, so I’m not particularly worried about misalignment or vibration issues. Also, a flexible coupler probably wouldn’t have fit in the pump housing. The other two things that come up are 1) why not modify the shafts, and 2) why buy something to make it work. The answer is: because Jeremy Makes Things. I wanted to see if I could do this, and do it as close to the right way as possible. I knew the theory behind doing an internal spline, but theory and practice are two different things. I wanted to push my skills. As happy as I am with the end result, this project was just as much about going through the process.

[@CraigsWorkshop]

You're doing an awesome job here, I hope you don't feel the need to justify all your decisions to any naysayers out there. Great to see you pushing your skills. Just keep on keeping on, you're doing all the right things 👍

[@steveveness3829]

G'day from West Australia🙂 As a 3rd gen engineer with 40yrs of trade life. Well done buddy well done indeed.🙂👍👍

[@aerialrescuesolutions3277]

Well said. Thank you for a great video, I learned a few things. Awesome.

[@rickpalechuk4411]

Jeremy makes things, not Jeremy buys things.

[@Blue.star1]

How much did you charge

[@temmellese6730]

Nice to see a machinist who is more about the work and less about the image and vanity. Great to see real old school tools being loved and worked. Subscribed on first go.

[@TomHerd-vm4vf]

All I have is old stuff. 🙂

[@fishydubsfishing6516]

I just love when somebody else volunteers your services

[@everettplummer9725]

We had a spline shaft come in pieces, to the shop. I made a series of kerfs, carbonized it, and heat treated. Made a short broach to clean up the spline. Used a dividing head for the shaft. I think you should always knurl, as slow as it goes. Too often, the knurling wheels, weld on to the pins. Can't keep enough oil on them, knurling can produce a lot of heat.

[@MarionMakarewicz]

I love your "toolception". Making a tool, to make a tool, to make a part to fix a machine.

[@bobvines00]

Jeremy, Thank you for sharing your (mostly) entire thought process plus the "oopses" that you ran into instead of doing like most channels that "hide" their mistakes and other things that don't go correctly. Seeing how another home shop Machinist goes about a job with similar (actually better! ;) equipment and raw materials is very helpful as well as giving an idea of that "aw sh**s" to expect is worth its weight in KZbin gold!

[@Johnny-uy4iu]

That was my favorite part too. A lot of machinists channels will show a failed part, describe what happened and a quick shot when they chuck it back into stock. I like that here he shows exactly why it messed up and even keep going until it’s beyond repair, exactly what I would do 😂. None of that perfect machinist crap, just what will get the job done is encouraging for a hobbyist like me.

[@windrk_6754]

Yes, I think much of what we learn in machining is by 'oopses' (breaking taps, broaches, parting tools, things not fitting, sliding off mag chuck, etc etc) - and its much better to learn from other people's mistakes - so thanks for the contribution towards saving the world so much ruined tooling & projects!

[@CarbonBadger]

I was really impressed not just by your skills, but your camera work, narration & the inclusion of issues in this difficult project. I believe this demonstrates your high intelligence & educational ability. Any student would be lucky to have you as an instructor. 👍

[@konradbob7660]

I totally agree!

[@suburbanagrarianproject9003]

I have a machine that requires a splined receiver/coupling for a splined metric shaft. I can't believe how hard it has been to find one. You've made it look like child's play.. Great job!

[@rustylugnut755]

Thank you! As an old fellow who's been around and seen a few things . . . I learned a few things and was entertained in the process! Thanks again. You have a new subscriber.

[@cav89-]

You know you achieved complete machining self-reliance when “That’s probably not the last one of those I’m making” Is followed by making a goddamn broach. And to prove it, just make another one! Awesome job!

[@windrk_6754]

Yes, nice job on the broaches.. although seems like with a shaper, could have made a tiny square slotting tool?? Maybe that's actually more work, once a couple of them have gone 'tingggggg..oops'... & maybe could have used the 5C indexer on the grinder to grind the broaches... requiring another fixture to hold the indexer plus a tailstock long enough, crosswise on narrow mag chuck.. but useful for future...

[@LetsRogerThat]

Jeremy, a while back I had a similar problem with a splined shaft from a Volvo Penta transfer shaft. In my case, splines were worn due to hard shifting and the metal not being hard enough. So, I simply converted the splined shaft to a hexagon and that made the process much easier, not to mention harder to wear down. Great job. A pleasure to watch as always. Gilles

[@azarellediaz4892]

Next time, if you have access to a comparator you can use epoxy to make a copy of the shape on the splines, align it on the comparator and find the exact angles and measurements you are looking for, lightly coat the splines with oil, anchor lube or Vaseline to keep the epoxy from sticking, it works perfectly and no much need to hunt for information. Great job on this build, I did learn some points on how I can do better next time. Thanks.

[@windrk_6754]

Another key way to measure splines (external or internal) is by a dimension over pins.. I think the pins need to sit on the pitch diameter of the spline, and it should be possible to calculate it using CAD & approximating assuming a straight sided spline tooth. Great video! & great that this was a 'volunteer job'! (wonder if you heard anything back from them, is it still out there pumping away?)

[@mumblbeebee6546]

Congratulations Jeremy, your persistence and make-do attitude are always inspiring and the end result is a complete success!

[@munter10]

This was great to watch, I’m a retired automotive engineer and have always been fascinated by one off projects like this. Bravo!

[@yanisgerber4758]

I'm pretty impressed by the homemade square broach! Well done...!

[@MrBlackbutang]

Think the world forgot about good tool die maker. Everything that works mechanically has a good tool maker behind it. Thanks

[@johann-pauluspaul222]

Meine Hochachtung für diese gute Arbeit.

[@DangerousSportsForSeniors]

I loved reading your whiteboard. Always subtle. Thanks for sharing

[@pink_love_cat4928]

I have worked on alot of these submerged pumps and you've done a GREAT JOB making them fit together . The different companies intentionally made their connecting shafts different just so the average person couldn't connect them together they want everyone to buy a new pump and motor together but if you had the other two half's you could have just changed out the shaft witch is possible in some pump's or cut the shaft short turned down the end and pin or weld on the right shaft connecting head. But AWESOME JOB !!!

[@jrb_sland]

I learned something new - when using setscrews to secure a hardened tool in a shaper, use at least TWO setscrews at 90 degrees to each other! The tool pressure is clearly immense. Machining a couple of mating dimples into the tool might also be useful (?). Great video. Many thanks!

[@horsthacker9990]

i like your sense of humor.. Seeing that i am not the only one, whose stuff flying around and never got found again , and also things just go wrong, get me a feeling, Not to be alone in a world, where people got hated by things.

[@TomHerd-vm4vf]

I really like the fact you had to make a number of "tools" to finally get to making the project. Seems to happen to me on my projects (now retired so I can take all the time I want). Also, finding that what I think should fit on 1st try .... well... you know. THANKS!

[@brunosmith6925]

Always inspiring to see someone engage brain and not give in... My projects are no where near the complexity of this one, but after watching this, I now know not to give in!

[@breakerbarranch5617]

Admire your skillset ...and your patiience in seeing the project to the end. Thanks for showing the mis-steps as well for us imperfect learners out here.

[@ferrumignis]

I dread to think of the number of hours you put into this, but the results are very pleasing! I think a machinists jack might have been useful under the end of the workpiece on the shaper, it did seem to be deflecting a little.

[@ferrumignis]

@@tg5509 Where are your videos of you machining internal splines? Surely a real "expert"like yourself would want to show how it's done properly?

[@1981lowrider]

Your skills have elevated you above the realm of mortals. Well done Sir.

[@northernmetalworker]

I love the fact that your knuckles are positively devastated with cuts and Knicks lol, that's evidence to me that you've been fighting with this for a while!

[@henrytupper6959]

I work in an old school machine shop. Never made a broach, so I appreciate your efforts.

[@WilbursTravels-ArielSquareFour]

A masterful piece of work and patience! No more buying broaches for me, I've got the shaper, heat treat oven and oil so no excuses. Just a note on the hex holder tool you made, if you part off a little brass disc and put it into the grub screw hole before the grub screw, you won't get all those marks from the screw tip on your nice hex mount tool 🙂

[@budstep7361]

hoping the pump was worth it! Gotta make sure it's properly matched with the motor and both worthy condition of such repairs and installation, but your metal work was beautiful! Thanks for sharing and teaching the craft!

[@arthurspader5423]

Your skill at machining is amazing. You put all of the effort in your projects and they surely pay off! I still can't believe you just have 8k subscribers

[@gw10758]

8001 now

[@phillhuddleston9445]

One tip, always use cutting oil when threading whether taping, using a thread die or single point threading and when broaching.

[@duanehylton8074]

Very nice video of making parts that match through trial and success. I especially liked watching the test runs before taking on the final piece.

[@matthewheaton4421]

Great job, I have always wanted to grab a shaper but am 100% out of room right now.

[@paulmanoha]

Mad respect for the skill, patience and commitment. Great work!

[@gregoryburne5251]

I love hearing the thoughts and mindset of kindred spirits. My first video of yours, and I thoroughly enjoyed it. Nice calming voice, and the patience of a cat. 👍🇿🇦

[@somepplskids4008]

Handled it like you've done it a million times before!!! Three thumbs up!

[@passenger6735]

Excellent piece. I can almost feel the sinking feeling you get when you've put a ton of effort into something and it's not perfect. Seven attempts at a fit was well worth it. The only thing I'd have done different after all that work is to paint it bright orange and put LED lights around it!

[@tfogelson3139]

Was working on the bomb bay doors of a B-17 and they used a splined shaft sliding thru a bronze coupler to compensate for the length of the actuator shaft changing as the doors opened and closed. Parts for an airplane this old are usually made of unobtainium but the factory drawings for the parts had the manufacturer of the spined shaft and they are still in business and they still make it. Purchased 6 feet of it and used pieces of the "pinion wire" to make a broach and then drilled some bronze for the couplers. Once the couplers were broached the fit needed to be a sliding fit and so a lot of valve grinding compound was used to wear in the couplers.

[@merc7105]

Sometimes the Recommended knows exactly what I’m in the mood to watch. This was very engaging, thank you. Subbed.

[@theasiamtmgroup]

That was awesome to watch, you're a really skilled machinist.

[@noe616]

That was a lot of effort and expertise. I'm blown away.

[@ronmurphy9819]

You and Rustinox sure make a good case for the shaper. I definitely want one now. Thanks Ron

[@nefariousyawn]

That was awesome. I admire your patience and commitment to this project.

[@bdove7939]

Comically large, but awesome. Thats one for the books. Great that you are helping out. No good deed goes unpunished.

[@AdamBereki]

Thank you for your authenticity in sharing this project! I so admire your abilities to adapt and overcome issues.

[@mafosa9563]

looks like most of the grief was at "set up" "time consuming!!!!!"..... great share !!!! larry

[@lolcec81]

Спасибо что помогаете людям своим трудом механической обработки метала.

[@idkmachining6892]

You made a square broach and then used said broach without cutting oil, absolute rockstar!

[@bmartinot]

Don't put yourself down so much matey. It's awsome what your able to do.

[@califuturist]

👍🏾👍🏾👍🏾👍🏾👍🏾 Now I see what needs to be done to attach a pinion shaft directly to a tail shaft for a mid-engine design.

[@matus1976]

Nice job! I recently did a simple keyway broach, and then used what I learned doing that to make a backface borer. Seeing the same idea used to make custom spline shafts is really cool.

[@warrenjones744]

I have seen your channel on the suggested list on the side of my screen and never paid much attention. however...Splines?...This one caught my attention. I am glad I checked it out. I am in the field repair business and admire a craftsman who can sort out a problem, use what he has and make it work. I would suspect not the way the factory coupler would be made, but what a project to learn how to do or perhaps how to not do something for the future. Bravo Zulu sir. I am going check out what other stuff you have made. Cheers

[@staceyporter6095]

Nice job! People don't realize the obstacles you have to overcome in building, what seems to be, such a simple part.

[@EdA-qh7qr]

I envy you i no longer have a machine shop to work in great job

[@neilbarnett3046]

This is the sort of thing my granddad used to do for his job at Massey Ferguson, so impressive. I used to mend computers, but that was a different matter. I must admit, I was waiting to see whether there was a moment when you found out that after you'd done all this, the motor was going to turn the shaft the wrong way, but it never happened.

[@TheTsunamijuan]

Impressed with you making your own broaches, had never thought about that before. Definitely subscribing to see what else you build in the future. Great stuff!

[@johntenhave1]

A mighty fine effort, Jeremy. As you point out there is a world of difference between theory and practice. You mastered both!

[@hudimarkus395]

Great work on the slotting, Although I would recommend using the standard tooth to slot the correct profile. Seem like an application in which high RPM is experienced, its prone to quick wear and mismatch. You should be able to hear it with time (if occurs).

[@oldmanonabike233]

Well as an amateur, I found this video absolutely fascinating. Thanks very much.

[@kensnyder9372]

Very good job !!! ...It is good to see someone that can do something with out a ""CNC"" and a stack of lap tops

[@sweeneymotorsports82]

Well this is weird, random video on Sunday morning, I’m 24 seconds in, was this veteran memorial in Franklin, NH. I’m also from the area so cool to see local content

[@messenger8279]

Well done. I would not have finished this project, I probably would have given up on it. I don't have your patience. Came out good.

[@oscarutrera9829]

Lots of work and I’m pretty sure it took a lot of hours, but the end result was great. Nice job.

[@CraigsWorkshop]

Loved it. Yours is one of the most refreshing and honest machining channels out there. Love the seat-of-the-pants engineering, and the excellent result at the end. I would find making those parts way too intimidating, and put it off for years, so hats off to you for getting on with it. Keep on keeping on 👍

[@ronnydowdy7432]

That's the smallest shaper I have ever seen but you did very good job with it. I have enjoyed watching this show very much.

[@arturoaguilajr2009]

This is an excellent trade to have under your belt..you will never go hungry..

[@PhilHattonMakesStuff]

Fascinating! I'm happy the algorithm suggested it.

[@sharkbaitsurfer]

You've got some great skills and tools to put them to use - colour me very impressed! I really enjoyed that video

[@michaelbabatunde3915]

Your skill is highly commendable

[@mnrracer]

Awesome, the only way forward is forward, not many people that try hard anymore. Hopefully you inspire more to try.

[@clivehaynes2183]

Loved it and it was kind of pleasing to see that I am not the only one to make mistakes.

[@nonyb6365]

Great job! So fun to watch. This is really splendid workmanship! 🙌

[@TheKnacklersWorkshop]

Hello Jeremy, Nicely done... enjoyable viewing, thank you... Take care. Paul,,

[@pyromedichd1]

Very nice job. Hours of love went into that project.

[@loganlawlyes1980]

For your backing out problem you had with the hss cutter in your spline maker, try putting in a center drill divit where the set screw seats. It should greatly reduce the chance of it backing out and loosing your measurements

[@spiKey0svetlana]

The man's got some serious skillz! When he took that book out.... 😅

[@liveupmatt]

Really like you content and the way you revive old tools, also think you are funny. Thanks for making all of your videos!

[@Cepzg1981]

Спасибо,за ваш труд. Ждал,когда ваше изделие будет работать.Много дорогих станков,чтобы сделать то ,что работает неизвестно как.

[@irench]

That was long but great. Watch Wes Work needs to watch your channel, A hydraulic barrel cylinder had a spline that got super sloppy. A perfect job to bore out the hole and make a pressed fit replacement as well as weld up and spline the shaft of the barrel cylinder.

[@humpteedumptee8629]

the amount of wobble at 11:15 is glorious. when this dude says its not exactly straight he is incredibly optimistic!!

[@JeremyMakesThings]

That was where I parted it off into two pieces.

[@humpteedumptee8629]

@@JeremyMakesThings it was nice work. without cnc and cam. I woulda needed several runs before anything worked out.

[@DaveFromColorado]

I always wondered how internal splines were actually made ... it looks like y'all went through some hell.. but I thank you for sharing.

[@tylerd55555]

Great video. Loved seeing the way it is actually done not just a perfect edited video like most vids

[@bulletproofpepper2]

Had a project coming up so I watched again, I will have to do it with my lathe to push the tool with the saddle.

[@sachinkapatkar]

Nice work. Try to punch on the spline tool u made on side where the locking bolt rest. So that it locks with the hex threaded bolt u used. And the tool wont get shifted. Best of luck.

[@Joe.O_623]

Excellent job on this. I hope you keep making videos.

[@martinswiney2192]

Great job. Never seen anyone make their own broach before. Cool. Good idea with the test pieces too. Hate to tell you this but im in the pump repair business and that part was probably available commercially. Either the dreaded Motion Industries or my favorite here in Alabama is Bearings and Power Transmission. They have all sorts of couplings like that.

[@daniellewis1789]

Thank you for helping out a community ski hill!

[@patrickbrown7491]

Very interesting, like the broach making process, also small indexing head.

[@mftmachining]

That was a tough one....but you pulled it off...congrats, great job.

[@torchofkck4989]

Excellent work on the hard coupling. Thanks for sharing. Maybe some day you can make a set of couplings for a spider gear. I believe a lot of viewers would enjoy the process & application.

[@nicholascampo6010]

Thanks for helping man. I live nearby. Crazy I stumbled onto your video. Very cool

[@oh8wingman]

I had the same problem with a tool sliding in a boring bar while single point threading some ACME nuts for a project. What I did to stop the problem was grind a small groove in the side of the cutting tool so the set screw had something to locate on and bind in. The tool never shifted for the remainder of the job once tightened in place. Another solution I have seen is to bore a small hole in the side of the boring bar the intersects the square hole and tap it for a second set screw. With two screws the tool is held more securely an is less likely to slip.

[@davidsnyder2000]

That part came out awesome Jeremy👍 I know for certain I couldn’t build that coupler….especially dealing with splines. You did a really good job there….something to be proud of🙂

[@officemanager1241]

Liked that the build had a meaningful purpose. Great video

[@Vikingwerk]

2:16 when you do a bunch of passes in fast forward, then show one pass in real time, my brain instantly goes “This is either the finishing pass, or the *disaster strikes* pass.” 😂 Also, love the to do list on the white board!

[@LordOfTamarac]

Amazing work man, I’m hobby machinist too but I could not have pulled that off, kudos to you.

[@optomechman3k-sx3nl]

Great, fun video. Haven't used a shaper or planer in decades. But I need a cheap and simple method of creating internal splines. Short of broaching, it's not going to happen in solid metal. With some compromises, may be able to mill acceptable ribs.

[@tomliemohn624]

Nice project. Looks good. I have yet to build a broach, but there have been times when I could use one.

[@ssnydess6787]

I wish I had your bandaid contract, lol. Excellent!