Gear Hobbing Attachment (milling machine) Part 2

[@billgilbride7972]

Thank You for not only providing a veritable course in metal working, but for taking the time to document it in such a professional manner. Best Gear Video Ever!

[@amandabeck2024]

Yea. Hats off to you sir. I have a degree in CNC machine tool. Now I've seen and done lot of neat shit on these mini manual machines. Guys home making all kinds of tooling and attachments for all different kinds of operations. Machine modifications to add capabilities, automation builds, CNC conversions, rebuilding entire machines all that. Your build here tops them all. Average hobbiest aside even for me It's about hard enough to set up a mill with a rotary table and indexing plates and a standard convoluted cutter to cut a gear one tooth at a time. Here you are home building an attachment to transform a Harbor Freight mini mill into a gear hobb. That is truly amazing and worthy of praise. Again hats off to you my friend.

[@akfarmboy49]

I’ve been in the trade for 40 years. I’m impressed by your gear cutting. And your electronic gear indexing

[@AndysMachines]

Thanks very much! 😁

[@fredrezfield1629]

@@AndysMachines can you do splines this way too? or that's broaching altogether?

[@AndysMachines]

Yes you can hob splines, there are special hobs for doing this. internal splines need to be cut with another method though (broaching, shaping, skiving).

[@yoashuain1]

That nut design is the smartest thing I've seen. Brilliant! Self locking and non slipping, brilliant!

[@drakefallentine8351]

A stunning presentation by every measure. Excellent close-up photography with perfect lighting. Very well thought out and clear dialog...no "um...er...ahh" to waste time. Superb!!

[@aramroshani6197]

It was a huge pleasure to watch someone did a project from A to Z without any default. It shows lot of things: Solid theoretical background decades experiences in manufacturing and perseverance accumulated behind this excellent realisation. Thanks for sharing every details.

[@arthurybrenin3878]

Bursting at the seams to give this multiple likes. Sublime

[@yoashuain1]

The builder of the machine that lets you build endlessly is the True genius, and you Sir are truly gifted! Thank you so much for this. Now I must build my own mill. 😁😁😁😁😁 5 Stars!!!

[@machinistzhang3632]

Genius, you just explained how gear hobbling works. I watched your video 5 times, now I understood how hobbling cutter works. Thank you !

[@peterfitzpatrick7032]

Hobbing ... not hobbling... 😎👍☘🍺

[@jerryweaver2247]

The amount of engineering steps to making gears is intense. I have a new appreciation of the little things that makes life easy.

[@Jibs-HappyDesigns-990]

🤖🍖me2

[@sambigel2424]

Hi Andy How to sync the index head with machine spindle? Is it possible to use closed loop stepper motor with harmonic drive for hobbing instead of belt drive? Thanks in advance.

[@mitchstilborn]

Ok, had to subscribe. I’m a professional mechanical engineer, and I have taught the machine design course at my local university, which includes a couple chapters on gears. But your explanation of how gear hobbing works (including a perfect animated illustration) was masterful and eye-opening. And how (relatively) simply a hobbing setup can be made…. wow. This just went on my last of projects for when I can finally build my garage shop.

[@jeffanderson1653]

I bet it’s very satisfying to be able to produce such a fine instrument with hobby machines. What are you, some sort of genius? I’m now a subscriber. Well done sir.

[@seamusbolton215]

I have watched thousands of machining videos and this was without any doubt the most interesting I have ever seen I cant wait to explore the rest of your channel You have inspired me to get back out in my own shed and dust off my own Colechester Student Thank you so much

[@danielmahon1589]

if there is ever an apocalypses machinists will rebuild the world.

[@benjamindeverell1123]

Well, yeah, they built the current one.

[@henrydando]

they built the one where living in now

[@matthewmoilanen2413]

Ya that will work great with no power to run their lathe and mill.

[@apache16492]

@@matthewmoilanen2413 we used to run those off giant pulleys run by water wheels

[@owen368]

@@matthewmoilanen2413 Think there are enough other tech's around to sort them some power.

[@ausfund]

All I can say mate is, thank you for your beautiful expertise. You are truly a craftsman. Cheers.

[@davidcastanedajr.1268]

I was in awe watching your videos! Such precision made look so easy. My mind is boggled!

[@pgsibilo]

I'm only here to just watch, but I got to say, KZbin was made for people like you, which I can't say for many others. Great Video 👍🏼👍🏼👍🏼

[@MartsGarage]

Very very impressive. I've learnt a lot from your gear cutting videos. Thanks very much for taking the time to put them together and explain all the little details in such an understandable manner. Mart in Solihull.

[@ericeller9165]

That's beautiful work. My father was a machinist and fabricator, this is like watching him work again. Great fun 😎

[@pettere8429]

Damn, now I want to get a lathe and a mill just to build accessories for them even more than before. Well, it is something to dream of for retirement.

[@AndysMachines]

Yes, I seem to spend most of my time making accessories for machines I already have, or building new machines to do one type of operation I can't already do.

[@rustedfriend]

Best explanation of gear hobbing that I've seen yet. And also thanks for demystifying cutting helicals. I always thought there was a lot more magic to it than just "tip the gear, then do the same thing" :P

[@AndysMachines]

There's a little more to helicals than 'just tip the gear', the calculations for correct pitch circle diameter are a bit more complex, but nothing too scary. Now hypoid bevel gears, they mystify me!

[@rustedfriend]

@@AndysMachines Haha, fair enough :P Still less magic than I originally imagined.

[@TaylorTheOtter]

You very obviously can't hear what I'm thinking because I was completely in awe of that plastic gear. To then do it in steel is mindblowing! I hope I get the chance to play around with stuff like this one day. I'm allowed to play around with my mentor's mini lathe and I'm planning to get myself a micro lathe (like a clockmaker's lathe) when I find one in good condition. It's a long road between that and gear hobbing but that ain't gonna stop me!

[@jhongery3853]

I used to study machining. However, I would be happier if I were your student

[@CalvinoBear]

I was blown away when you started skiving on the damn thing. SUBBED!

[@richard-sim]

wow - such an amazing tool! I especially enjoyed your attention to the mechanical fit and alignment of all the parts, use of locating features, etc. Turely impressive work in every aspect. This is definitely in my bucket list of projects now. :)

[@Danny-qb2fd]

Thanks. Ambivalence in decision making on mill upgrade has now been overcome!

[@SIB1963]

I do not even own a lathe, much less a mill. I have never machined anything in my. life. But I feel the need to make and use a hobbing attachment. Somehow, I need to make lots of gears.

[@fredbloggs4829]

I have been waiting so much for this final video to come out. Absolutely brilliant bit of kit you have put together. I specifically liked the pre-tension nut for the angle bearings. What would also be great to see is these gears in use. For example to make a planetary set of gears and then run it at relatively high speed.

[@AndysMachines]

Yes, this hobbing attachment (and gears made with it) will certainly feature in future videos and I can think of a couple of applications for planetary gearboxes. It may be a while before I get round to it though (never enough time!)

[@tonywilson4713]

@@AndysMachines Well done on this overall. It would be great if you could do a more in depth take on the spindle. A lot of people don't know what it takes to make a shaft rotate with high accuracy and very low run out. There are more than a few people doing their own CNC mills and lathes here on YT and its obvious to me they don't understand the concept of mounting a shaft that will maintain its precision over time. I don't know your background but its more than just precision machining. That part of the first vid when you checked the run out on the collet mount was scary for how accurate it was. The fact you know how to make and install a quadrature encoders is super impressive and I wished more people would pay attention to that concept. I've done 30+ years of automation and very few people are even taught what you know to design and build. Robin Renzetti is one of the very few KZbinrs I have seen who knows how to design and build high precision hardware. I have worked with precision tool makers and instrument makers and they have a different mindset to normal machinists. About the only thing I would have done differently would have been to use a servo instead of a stepper but that's my bias from robotics and I know how to use them.

[@tonywilson4713]

@@AndysMachines You're absolutely right about the mechanical part. No amount of software can ever truly fix a bad mechanical setup. It might improve what ahs been built but it can never solve. That's a very hard lesson I see way too many mechanical engineers NOT EVER LEARN. I hope Robin is back doing regular vids soon. I really want to see how that hyper precision indexer turns out. Its not that dissimilar to what you did. Its a very simple system capturing a rotating shaft in fixture to rotate accurately. Its just he's taken it to a whole different level of precision.

[@WeCanDoThatBetter]

What a cool project, really impressing! I like the etching technique. And what a cool idea to use this assembly for skiving internal gears. Great content. Thanks for sharing.

[@AndysMachines]

Thanks! I use this etching technique quite a lot on things like control panels, this wasn't actually a particularly good example, there were a lot of scratches left on the milled area by the endmill I used which spoiled the look a bit.

[@WeCanDoThatBetter]

@@AndysMachines Anyway, the technique is ingenious :)!

[@peterellis6556]

@@AndysMachines Where do you get your electroetch masks, please ?

[@peterellis6556]

OK. I saw the answer lower down. It sounds like I should visit my local advertising sign maker as I´m not likely to get enough use out of a dedicated vinyl cutter. I´m familiar with electroetching and used to have an electroetch machine where the supplier did masks, too, but it is 40 years ago. Thank you for reminding me of it !

[@pieterveenders9793]

@@peterellis6556 You could use the same technique as what hobbyists use to make their own printed circuit boards. In order to make those they coat copper clad PCB's with UV sentitive photoresist, print a negative of their design on overhead transparency sheets, place the sheet over the photoresist clad PCB and then expose it with UV light from some UV LEDs or UV tubes. After exposing it the required amount of time the board is dunked into a soda or weak lye solution to dissolve the bits of photoresist which were hidden behind the black ink of the printed design on the transparency sheets and as result didn't polymerise by the UV, and then the plate is removed from the solution and rinsed with some tap or preferably demineralised water. Then the board is placed in a tub with etchant solution (ferric chloride, sodium/potassium persulphate, or diluted hydrochlorid acid with a small amount of dilute hydrogen peroxide) to etch away the exposed bits of copper of the PCB, and hey presto, you have a developed PCB with all the copper traces and pads just where you want them. The same technique can be used with other metals as well, including steel and I would assume aluminium. And its probably a fair bit cheaper than the vinyl method.

[@chauvinemmons]

It's one thing to make a part and the entirely another thing to instrument it and bring the whole thing to life. I many times people only know the part that they know it can take four or five people to build a simple machine only years of experience can make this possible if you're willing to step out of your comfort zone.

[@davidmott2090]

beautiful craftsmanship.

[@ThePapa41]

what a great display of ingenuity, outstanding work!! Louis

[@rodrigogarcete1565]

I hope I can become as good of a machinist as you are, that is some solid skill right there

[@StaPerRa]

It's nice to look at the work of the Master! Especially without using the archaic imperial measurement system.

[@chauvinemmons]

Careful they still use whitworth fasteners 55 degree thread angle unless you're at or under a quarter inch 54 and 1/2 included angle. I noticed he uses metric good for him. You know there five different metric standards. I made parts to mount a Garrett turbine TFE 731 high bypass engine on a pair of Desalt Falcon and Condor Business jets to get FAA certification in flight by removing the one of the existing engines replacing it with a Garrett model as most modern twin engine aircraft are certified to fly with a single engine it saves hundreds of thousands of dollars testing etc we did all the engineering made all the parts even installed everything, next thing you know I'm getting a call from an engineer desperately wanting to know what the hell I did wrong they were trying to add something the ISO metric bolts they had would not fit. I told him I used the French standard he was puzzled it's a French aircraft dude I wrote it down on the blueprints if he would have bothered to read them. Here in the US we must deal with all of it I've made many an adapter to go from certain British taper pipe sizes to American taper pipe. On regular Straight pipe most of their threads are off by one pitch we add extra pipe snot and use a bigger wrench On one project because somebody cheaped out on the gearboxes for the Central Arizona Project bringing water from the Colorado to Phoenix the size of pipe plugs used doesn't exist here like not even close. Some of the Indians didn't feel they got their fair share of water so they were loading the gearboxes with gravel, the solution was to put locking pipe caps on the gearboxes right up until they couldn't find pipe nipples that would fit to screw said locking pipe caps onto priceless. More like about 60 adapters at around $50 each.

[@chauvinemmons]

Not sure why they would call it imperial that's what they should call the British whitworth system. Here in America we use inches which have nothing to do with a damn thing. Why you got me not divisible by anything makes computers insane only thing worse is when people try to convert metric to inches when they're trying to hold tenths of a thousands of an inch on CNC machines. The control turns the motors that turn the screws.... you guessed it! Metric Screws so you end up with a double error someone asked me why don't they make inch ball screws Id like to smack them with a ball peen hammer idiots. What would you use for a conversion factor how many places would you take that out and still be wrong unbelievable. Some of the bolt patterns on jet engines make me crazy. I use the dividing head with a plate you still have to put a fudge Factor in by adding or subtracting a hole in The mask plate, and if you're smart you'll break that up by some amount equally which is impossible I always try to break them four if not five times depending on the tolerance typically as I cross an axis if you looked at it that way even though I'm turning it radially. What division plate would you use for 109 holes on a 762mm diameter on a Bridgeport that only has 225mm of travel in Y. Be careful one hole at 12:00 is offset from it's normal calculated position, only in the x-axis by 1.25 millimeter now imagine if you look at the part the first hole at the top now at 9:00 your left hand is now zero you're at zero because you're using the x-axis as your radius adjustment Y axis remains at zero except for this first hole the offset is made in Y. you get .002 inch tru position tolerance, regardless of feature size how many tenths of 1/1000 inches can you be off and maintain this position tolerance? How many Arabs can you fit in a tent-h anyway, it really depends on how big the Tent is. I live in microns thank you. Sorry bad joke I got a better one though Your setting up a machine you make the first part and send it to inspection. The inspector comes out and says you need to move over a couple Mills, that way. So you unbolt everything move down the line 2 machines and begin to set your parts up again there. Soon he comes back to check on things and says, What the hell are you doing?

[@pieterveenders9793]

@@chauvinemmons It must be frustrating to work on vehicles of projects that cost upwards of millions, only for it not to work, or even worse, utterly get destroyed because someone used the wrong type of bolt. Hopefully one day the last few countries will join the rest of the world in using the metric system and nothing else, it would save a lot of people a lot of headaches and money the world over...

[@nkelly.9]

Highly impressed. Thank you for sharing your considerable skills and knowledge.

[@who-gives-a-toss_Bear]

Bloody brilliant. When you need something, how do I do it with whats on hand. This Guy takes it to the next level.

[@gyrogearloose1345]

Thanks for this Mr Andy! Very inspiring, lots of interesting solutions. And a huge amount of fine work on your part.

[@Migueldeservantes]

Interested in the box controller for the Stepper motor!!! would you care to share where can I get a hold of one of them??

[@AndysMachines]

That's something I built about 10 years ago for my previous milling machine, the electronics are a little dated, but the parts are still available.

[@RixtronixLAB]

Nice info, thank you for sharing it with us, keep it up :)

[@Blowjin]

A great like for this job! Thank You!

[@garul1669]

Magnificent job and magnificent video. I saw a great commitment and a great skill, I have a lot to learn from people like you

[@matthewf1979]

Very ingenious way to cut gears, or whatever else that requires precision timing.

[@AndysMachines]

Yes, good point. It can not only cut gears, but also splines, toothed pulleys, sprockets, graduation marks, very precise knurling, in fact almost anything you want to repeat uniformly around the circumference of a part.

[@thebotformalityknownasdale2564]

Wow you have done some very nice work sir.

[@carlospolo946]

Amazing Job!! Congratulations 👏👏

[@bikefarmtaiwan1800]

Hats off to you! Very well thought out and executed! It is a bit of a mind bender at first . I seems like gear sciving is a kind of rotary broaching technique. Outstanding!

[@AndysMachines]

Yes, actually it is a very similar process to rotary broaching (the way it cuts)

[@fenchelteefee]

Awesome, cannot trust my eyes!

[@michaelrosenlof1084]

Another outstanding project, superbly done-entertaining and educational-Thank You Very Much, excellent ✅👍

[@millomweb]

9:40 I agree with what I've said about the marks the milling cutter has left but in this condition, the marks were the correct depth after all !

[@AndysMachines]

😁

[@NitroTom91]

These videos are some of the best machining I've seen on youtube. So much knowledge here. I will try and steal a lot of those designs ;)

[@maurodossantos2026]

Muito bom! Obrigado por postar esse vídeo. Havia meses que eu estava procurando sobre como fazer essas engrenagens. Nunca vi algo assim parabéns pelo conteúdo. Like e inscrito. Brasil BR

[@MrRander7769]

Time taken to cut this gear 2 minutes, time taken to know how to make and use these tools, a lifetime

[@henrikhv5084]

from my humble point of view, that was fantastic

[@PaulSteMarie]

Great video! That answers a lot of questions I've always had about hobbing and this sort of coordinated moves that's necessary to make it work. I love the way you're able to get that ring gear cut. It seems that that's broaching it though, rather than actually milling it.

[@AndysMachines]

Yes, the cut is taken in the downward direction by the relative movement of part and cutter, it's similar to rotary broaching.

[@j2mf]

thank you very much for sharing this piece of art with us!

[@smartypants5036]

I have watched a lot of mechanical engineering stuff on the web and this rates as one of the best presentations that I have ever seen. I have spent a lot of time driving stepper motors and the like with micro-controllers to drive telescopes and other equipment. Is there a past video or link to the BRAIN build. I have never worked with encoders and would like to.

[@AndysMachines]

Thanks for the compliment! Yes, there's a video on the brain here: kzbin.info/www/bejne/mJa3aWZnZ9Bmr6s One day, I'll do a video on encoders and how to build DIY ones (though I've quite a backlog of other videos to finish first!)

[@mxcollin95]

Excellent two part series. I learned a ton! Thank you

[@vaderdudenator1]

My man over here is absolutely out of control

[@Mister_G]

Very interesting build, thank you. Skiving was a new one to me.

[@georghofmann1782]

imagine a Gear-Hobber at home back 20 years ago i love what creative people with talent can do this days, with some "cheap" Arduinos and Steppermotors

[@thoadoublet5482]

impressive! looking forward to watching a stepper motor electric control system building video for details. thank you so much

[@JulianMakes]

Incredible skills and superb editing! So interesting!

[@MoshOrDie]

I’ve some manufacturing background too and studying engineering, I LOVE your video. Amazing skills, and man, that workshop🖤 really wish I can have something like that one day…well…maybe if I would study(as I planned), instead of watching youtube videos…immediately subscribed 👍

[@MrBhujbalgv]

Thanks for sharing this valuable information, love to watch this video. Great job.

[@mrvector257]

That diamond drag tool was pretty neat. Didn't even think something like that existed. Great video! Also, really great idea on etching the graduations.

[@clintchapman4319]

Awesome Bud!

[@CaskStrength777]

First of all- subbed, because this is the best example of a homemade hobber I've ever seen. Second- skiving is impressive, but poor results (wonder if it was because of heat treat on cutter?)- I'd love to see more of how the cutter geometry and centering of it is done. I'm aware of skiving before this, but was surprised when you pulled that out of the bag! Lastly- if you have a tool steel blank gear, and cut it to an exact length, with 2 deg. of relief on backsides of form from face- you could make a Hemingway rotary broaching tool- and broach external & internal gear teeth on things. That would be better result than your skiving. Running an MDF disk through the teeth charged with fine diamond paste after hardening would give excellent finish and make the cutter work better too

[@AndysMachines]

Thanks! The skiving was really just a bonus feature and not the main reason for building the attachment. I wasn't sure how well it would work, if at all. I don't think the heat-treat was the problem, the cutter didn't dull at all and cut plastic and steel with virtually identical results. I think the main problem was that the geometry of the cutting tool was not correct, skiving seems to be somewhere between hobbing and broaching and calculating the optimal tooth profile for the cutter. Chip clearance was also a problem, and probably other issues too I haven't identified. But it did work well enough to make a usable gear if only for light duty. Rotary broaching an internal gear is an interesting idea, I could make and harden a cutter easily enough (it would actually be an 'inverted' gear, with addendum and dedendum reversed). But I think it would require more force than my machine could apply except for a very small gear, as it would need to be done in a single pass. I might actually try this with the same 8-tooth cutter used in this video, making an 8-tooth internal gear, perhaps in plastic.

[@CaskStrength777]

@@AndysMachines Rotary broaching doesn't require tons of force- you just need things roughed out first. If you trace the pattern and mill out most of the stock by hand, it takes a lot of the pressure off. The wobble is around 1 degree, so it shaves very little but quickly with each rotation. For internal gear- yeah, you'd need a weird hob to make essentially the inverse gear form. I love this project, and really love how you showed the hobbing of helical spur gears simply. The video really made many things clear. I won't lie- I really really hope you cover the construction of this in every detail going forward- I really want to make one of these. I've done traditional gear cutting, but would love to get into proper hobbing.

[@alext8828]

I learned something today. And it's still early.

[@diegomartincavallo8491]

sos un genio saludos de argentina

[@screwsnutsandbolts]

Excellent video 👍

[@AndysMachines]

Thanks very much! 😁

[@screwsnutsandbolts]

@@AndysMachines You're welcome :)

[@jessebrown2723]

Super interesting and impressive! I would love to see a video of the encoder build!

[@jeffscott5133]

Thank you for this incredible video. I am going to have to get a lathe now, as I want to try this! Looking forward to seeing more.

[@arva1kes]

About the encoder wheel - its by far easier just to print it on transparent film. If its not dark enough you can print multiple and place it on top of eachother. We once did contactless analog potentiometer by printing gradient. It was for a racing wheel :)

[@AndysMachines]

Yes I actually did that for my previous gear hobbing attachment, but I found it not durable enough for a wheel this size. But for a small encoder you can completely enclose it works great. A more durable way is to cut the shape on a vinyl cutter and stick it to a thicker sheet of clear plastic, I suppose you could do this with a printed transparency too.

[@printnub7585]

Impressive! Cannot Believe that I am the first to comment. You sir have mad skills!

[@greglaroche1753]

Great video. Thanks!

[@guruhin6665]

Афтору уважение! Очень грамотный человек!!!

[@Mauri59g]

Ottima esecuzione, complimenti!!👏👏

[@larryschweitzer4904]

Impressive! I've only cut spur gears. The stepper seems like it could be applied to a semi-universal indexing head. Great video quality!

[@appleslider999]

😲🤩👍👍👍🥳

[@AlmostMachining]

This has been fantastic to watch. Thank you!

[@rolfvanderbijl]

Love the slomo, it's relaxing

[@estebanfranco5246]

Felicidades sr excelente trabajo y su diceño es increíble mi admiración saludos desde México

[@aldobruno712]

I wonder how you make those cool animation like at 2:51 I am binge watching your videos :) you are truly a master and I wish someday to have your culture, thank you very much for this content you are making

[@Lucky_Red_Fish]

Awesome work!

[@bananasba]

Cool device!

[@MachiningandMicrowaves]

Did you use a CNC laser for the vinyl mask or some more mysterious technique like Press'n'Peel? Very neat solution. I've tried making scales using a laser-printed acetate master and that UV iron-on film stuff with electrolytic etching, but it wasn't good on a stainless steel scale.

[@AndysMachines]

I used a drag-knife type vinyl cutting machine (as used for vinyl sign making). It's surprising useful to have one of these for all sorts of layout and mask-making.

[@millomweb]

An interesting lock-nut though. I've not come across that style before.

[@AndysMachines]

I actually copied the design from the one on my lathe, it takes up less space than 2 jam nuts, which is important when the spindle tilts to 90° to keep it from getting to tall.

[@jesscast5122]

Well, it's nothing new. and it's quite logical w a little brain use.

[@cvytnioy56dvfuj4g7]

Simply amazing

[@georgesbasementshop1240]

Bloody Fantastic :)

[@awesomecronk7183]

This is outstanding!

[@TheOnlyMosesMalone]

Amazing work Andy!

[@Waffenschmiedinx]

Awesome video

[@OHH6001]

High satisfying and amazing work !! Congratulations !! Louis. Oostende.

[@rwfisheriv]

Art.

[@davidharper4289]

Thank you so much for devoting your time to making this "Absolutely Outstanding Video" not to mention the cutter.........WOW!!!!!!

[@quixoticjedi942]

How are you getting around using a differential to cut your helical gears? Technically to cut helical gears with a hobbing setup you need a differential to produce the helix angle of the teeth, or you need to calculate an index that rotates the part faster for a given feed or a feed that moves in relation to the rotation of a set index to produce the helix. You also need to add or subtract the lead angle of the hob, or I believe the ones you use call it helix angle, from the helix angle of the gear in order to make accurate helical gear teeth. In your application that would mean either moving your spindle or part orientation. In a gear hobbing machine where the part is in a fixed position on the work spindle that would mean swinging the cutter head only.

[@AndysMachines]

Yes, a differential (with one input from the table leadscrew) is normally used in the traditional setup on a horizontal milling machine to advance the blank with the feed. The way I'm doing it is to tilt the machine spindle to account for the lead angle/helix angle of the hob, and tilt the hobbing spindle to the helical angle of the gear being cut. The cut is then taken in the horizontal plane and the advance is taken care of by the relative motion of blank and cutter. The only disadvantage of doing it this way is that the length of cut is limited since eventually the cutter moves out of contact with the workpiece, but it's plenty to gang mill several average gears together.

[@michaelbabatunde3915]

Very good innovation

[@lawmate]

Great design, very neat and compact

[@sd906238]

How did you make the control box from your previous hobbing attachment? Could you make a video on how it works and how you made it?

[@AndysMachines]

You'll be pleased to know I'm working on an updated version of the controller, I'll have a video on this when it's ready.

[@Smartzenegger]

You are an amazing engineer!

[@tannertrachsel1216]

Out of curiosity, why could you require a nut that puts pressure against the bearings if you press both bearings onto the shaft?

[@AndysMachines]

The back bearing is a looser fit on the shaft so it can slide to adjust the preload. It did end up slightly tighter than it really needs to be, but better than too loose!