How to identify unknown gears?

[@KallePihlajasaari]

Great video. My father was a gearbox designer and these parameters were often spoken of at out house. He wrote software in Pascal to calculate the various design parameters and working life according to the various DIN/ISO/AGMA/BS standards that all had their own quirks. and incompatibilities. All new designs were metric but he often had to fall back to the other standards when repairs were required for older imported machines. Trip down memory lane, thanks.

[@boots7859]

Got me with the Thanks for watching. Seriously though, that intro was perfect for figuring out Module gears.

[@mousemade1]

YT is full of over complicated, underinforming rubbish about gears. This is the clearest, most informative video I have seen. Well done!

[@anthony-o9o2i]

Can you tell me how to calculate the gear hob machine

[@WillDunlop-i3u]

This is a very clear and no nonsense description of gears / gearing - exactly what I have been looking for!

[@gutsngorrrr]

Excellent video, please keep them coming, as you are the only person I've found that is putting this in to term even I can understand.

[@richardjones38]

That's a great video, thanks. I reverse engineer gears so infrequently that each time I have to re-learn what little I once knew about it, which is time consuming even with the notes I keep on it. Your video is much more concise, and also showed me how to do helicals, which I've never needed to do. I'll be adding a link to it to my notes, and probably checking out some of your other videos too. Thanks again.

[@nunomiguelrodriguessilva3028]

This channel is better than school. Gratitude

[@michaelk5889]

Some subjects are best learned from a video rather than falling a sleep reading a machinist book. This is one of those subjects. Great info, thanks for sharing! 👍

[@neilbanks6845]

I used to be given chewed up gears to remake at short notice due to production breakdowns etc. It was like being Sherlock Holmes at times but very satisfying when I sussed out what it was and created a sparkling replacement for the grateful customer.

[@MrPTHANGARAJ]

Simple and useful video. First time I understood the left handed and right handed helical gear. Thanks a lot sir.,

[@chrismayer8990]

extremely useful! Thank you!

[@andrewhall2554]

Watching your explanation of the helical gear reminded me of a related experience. I worked with a mechanical engineer who specified which direction to feed the tap when tapping holes because he thought that tapping a hole in the "wrong" direction produced a left-hand thread. The machinists just played along with him. Since no incorrect threads were ever produced, the engineer never had any doubts.

[@AndysMachines]

I wonder if that would actually be possible with a very large diameter fine thread tap with lots of flutes? (And a lot of force). I expect it would just shred the tap.

[@andrewhall2554]

@@AndysMachines Sorry, I didn't write my comment very well. The fellow I was referring to would always specify which side of the part to feed the tap into. There was no intention of trying to feed the tap opposite to the normal direction. His intention was to tap the hole from the same side as the fastener was threaded in. He sincerely believed that tapping from the opposite side produced a left-hand thread.

[@KallePihlajasaari]

@@andrewhall2554 If he was making a taper pipe thread then he was right to be careful. :-)

[@slypig24]

Very clear and well explained. Looking forward to your next episode.

[@ophirb25]

You earned my subscription. Simple and clear explaination. Thank you.

[@garychaplin9861]

A very clear explanation, thanks Andy

[@TalRohan]

excellent description thankyou You didnt make my nose eyes and ears bleed from brain overheating and I can now actually do it..... thankyou very much

[@thigtsquare950]

Thanks for the refresher! It’s been more than 30 years I studied this topic, and now that I need it your explanation helped me a lot. Hey I even remembered where my notes were. I need 2 gears in my new (used) lathe and I keep messing something in my calculations. I should’ve started with module and, if not working with diametral pitch. Thanks again.🙏

[@folkkay]

Your video helped me, it's easy to understand thanks!

[@hiperformance71]

Tanks! I learned a lot about gears with your videos, never learned anything reading books about this topic! Now, a gear is less intimidating!

[@bryanburger]

Well done!

[@tebbiramzi5231]

The best and most wonderful explanation I have ever seen in my life Thank you very much and we want more videos full of knowledge Well done sir

[@sweetpeaz61]

Thankyou for making this so incredibly easy to understand its helped me a lot

[@dashrathkumargoranagorana197]

Excellent explained for gear module. Now you should make another video on bavel gear module formula.🎉🎉

[@samrodian919]

Excellent! I can now finally identify the change gears on my Chinese made lathe/ milling combination machine. It has some damaged gears and I need to make new ones so I can screw cut some standard metric threads. Obviously I need to know the module so I can buy the involute cutters to do the job. I've got a rotary table with the disks with different holes in them for setting up the number of teeth, god my memory is getting bad these days I can't remember the correct name for them lol anyway thanks for this video it's so helpful.

[@mattw7949]

Great video. I learned all that in school many decades ago, and The Algorithm must have known that I'd forgotten how to do it.

[@KW-ei3pi]

Thank you so much! I think it was my comment on your last video that prompted your making this one. I'm so glad. Now I have the information I need to either order an off the shelve gear for one of my old machines, or maybe even make one myself. Thank you!

[@AndysMachines]

Yes, it may well have been your question that prompted me to make this, though I've been asked how to identify gears a number of times, both on YT and in real life, so the next time it happens I can point them here!

[@sky173]

Amazing. Thanks for sharing. This is exactly what I was looking for. I'm just beginning to cut gears on my old Atlas.

[@9traktor]

Very fine explanation of this important technical fact. Great !

[@merlin1943]

It's an amazing compendium about gears identification. Kudos ! I'll save it for future reference. Thanks ! Edit: I'm anxious for part 2, bevel gears ? :o)

[@frogandspanner]

Each time I was typing a question the answer popped up! 20+ years go I wrote some software that helped me determine screw threads. I was restoring my 1966 Norton 650 SS at the time, and had biscuit tins with indeterminate rusty screws from previous repairs. The result was probabilistic in that, given diameters and very rough tpi/pitch, and correcting for 30 years of rust, a likely thread was proposed. It worked well. I wonder if something similar could be done for gears. The next step would be to determine screw threads and gear splodules optically, using a smartphone app.

[@mmnyako]

Just what I'm looking for. Thanks for sharing 🙏

[@nicholasmuller3021]

Terrific video! Really looking forward to the spiral bevel gear video as that's what I need atm. Thanks for explaining so clearly:)

[@TechnicalRangbar]

Very well explained good job Thanks a lot!

[@lcegraphicservices]

This really helped me to identify a helical gear! Thank You

[@pk07creation]

really nice video 👍

[@siratahlemuhammad8189]

I'll probably never use this knowledge but I really enjoyed it. Thanks

[@deanharris7149]

Great channel.

[@garyhardman8369]

A wealth of information. Thank you so much Sir!

[@andrewwakefield4519]

Well done - thanks! I look forward to the follow up video on bevel and whatever that last gear is called!

[@abdulkhalegalghamdi6635]

Very great explanation💐💐💐

[@billsill]

Very good job my friend.... 👍 👍 👍 👍

[@paulbriozzo4895]

Excellent video, thank you much!

[@Sigean11130]

Excellennt video, very clear, many thanks!

[@rc166honda]

Outstanding, stunningly informative. Many thanks for posting, subscribed 😊

[@TheUnimaker]

Great info and explanation. Thank you!

[@remyth6939]

This was exactly what I needed no more no less. Thank you.

[@sidewind131258]

Bloody hell, you had me at 1:10 And here I thought that TubalCain (that was a schoolteacher) made it easy to understand, you have him beaten hands down

[@TABE-O]

Thankyou so much for this!! Your explanations are very good 👍

[@jayantagoswami128]

Excellent Sir love from India

[@maloyaircraft1174]

Very informative! Thank you for taking the time to share

[@shashikantsingh6555]

This guy is legend👏👏👏 you cleared all my doubts🔥

[@alirezamirabdolbaghi651]

Very complete and useful explanations Thank you

[@mxcollin95]

Great video!!! Thanks for posting! 👍

[@dmitryp5530]

You are the best!!! Thanks for the video

[@nunomiguelrodriguessilva3028]

Thank you this is pure gold

[@somerandomnification]

8:22 Andy: "Okay then, what's this?" me "That's just like the one I'm trying to identify!" (except mine isn't helical) Andy: "Maybe I'll save that for another video." me: "Nooooo!!"

[@pepzi_]

Very useful! Thanks for sharing your knowledge 👍

[@farzamkarnia321]

great video! waiting for your next video to find out measuring bevel gears for reverse engineering and also a way to find profile shifting .thanks man.

[@RustyInventions-wz6ir]

Very interesting. Thanks

[@lazguevara151]

Damnit I wanted to know the last one lol nice video you do really clean work 👌

[@MyLilMule]

Great video, Andy. Don't be teasing me with that spyroid gear! ;)

[@robertelstad6602]

Looking forward to your «another video». Those helical bevel-gears are a nightmare to understand and even more so to replicate. Allmost there, CNCing in nylon, but still not perfect.

[@impactodelsurenterprise2440]

Spiral bevel to be exact. I used Gearteq to generate them in solidworks and sent them out for fabrication. They cost a fortune to make on those specialised gleason machines.

[@benjaminbergmann2607]

Great... What a cliffhanger, exactly at the moment when it got "interesting". Have to wait now for a second part, to identify my strange gear I have in front of me... :)

[@Madhankumar-bh4wz]

Nice

[@nicolasaudouard8956]

I have a similar trick to figure out which hand is my left from which one is my right: The right hand is the one that has the thumb on the left. easy.

[@gregwmanning]

Excellent learning video Thanks. But "what about the pressure angle" I was thinking. I am bogged down at this step, so I guess from your video I should just go with 20deg unless it looks too fat or too thin. With a small gear I find it hard to judge.

[@alextreseder6274]

You can use 2 guage pins and a micrometer and a gear chart to find it, but that chart may be extemely hard to find unless you have a gear textbook, and it would only work for even tooth count gears. The best way realistically is to genereate the gear in a cad program, add guage pin cross sections in sketch, and measure the distance in cad and compare to a micrometer measurement

[@richardhead8264]

For pressure angle of a spur gear tooth, find the point on the tooth that is radially 5/9 (0.5555) of the distance from the root circle, to the crown of the tooth. Find the centerline of the tooth. This is the tooth's line of symmetry, which passes through the axis of the gear. Measure the angle between the tangent line of the tooth at the aforementioned point and the centerline of the tooth. And _that_ is the pressure angle. *Example 1:* If you find that the point on a tooth that is 5/9 the height of the tooth, has a tangent line angle that is 20° from the centerline of the tooth, then 20° is the pressure angle.

[@mickyas1000]

BRILLIANT, I've been searching for this exact explanation in simple layman's terms, for ages, came across an American one, but he waffled on for over 8 mins what you explained in 1min. 😊😊 I'm assuming the 25.4 you mention is 1" in mm ?

[@AndysMachines]

Thanks! Yes, 1" =25.4mm.

[@justRD1]

Awesome video! Any chance of you expanding on this and laying down some simple techniques for working out the profile shift factor for non-standard gears?

[@automan1223]

the last week or so I am literally trying to run all this down for some old transmission gears that are no longer made / in short supply and trying to figure out how to I.D and make my own should it become necessary ! Thank you !!!

[@Jessica-mq3mm]

Thank you!! I bought a hand crank slicer and the handle with the gear is missing. I know what to look for now!

[@CraigLYoung]

Thanks for sharing 👍

[@kudui21]

I'm still wondering where that formula came from. Still great video. I'm already waiting for the next episode

[@karannayyar8030]

Great information....thanx

[@kunalverma193]

Great video you're the mech. God. Plz make for the bevel and other gears also...

[@garyknight3019]

Great info mate..thanks👍👍👍👍

[@HM-Projects]

Very informative, thanks!

[@ebrewste]

What a nice job!

[@aldobruno712]

can't wait for the another video you mention at the end (I think its name is a bevel gear)

[@gwaliorfoodfriend]

You are awesome 👍🏻👍🏻🎉🎉 .. you got my subscription

[@julias-shed]

Really clear thanks I enjoyed that. 😀

[@alextreseder6274]

Great video! What animation software are you using and do you like it?

[@PrinceArif007]

Good job

[@ApukEldar]

Bravo!

[@johnlarkin2980]

Brilliant thanks for this

[@CarlMikeyy]

thank you!

[@ashupeetu]

Informative, Thanks...

[@joell439]

Thank you 🙏

[@nedshead5906]

These videos of yours should be shown in trade school

[@mpetersen6]

Now what if they are Stub Tooth gears? Used to cut a lot of those. The Fellows variety. The pitch circle was one DP. And the tooth height was another. The gear pitches expressed by the pitch circle over the tooth height. One example being a 40 tooth 10/12 DP gear. A pitch diameter of 4.000 and an overall diameter of 4.000 + (1/12 x 2).

[@AndysMachines]

Yes, they would be a special case, which would fall into the category of 'all the other types of gear I didn't mention'.

[@neilbanks6845]

Experienced eyes would spot the pressure angle or stub teeth etc. Some corrected gears can appear a different pressure angle and when I used to design gears for the motor sport industry, We would often design gears with corrections so that standard tooling can be used for designing strong high pressure angle gears. (Not easy to spot with the nakid eye though)

[@russellwilson5246]

thanks i just learnt some thing...i guess the width will be called out for too.

[@sandyimperial5928]

Next video please new beast here from the Philippines 🇵🇭🇵🇭🇵🇭🇵🇭

[@ХамзатИстамулов-ъ4н]

😊

[@normesmonde5332]

Brilliant

[@machineworld1873]

I need that 😍

[@ledfootlou2540]

Please keep making videos, they're great! Why do you need to add 2 to the number of teeth when determine module or DP?

[@AndysMachines]

I didn't go too deeply into the theory in this video (I've covered this in other videos). The reason is that the pitch circle diameter of the gear is equal to the module x the number of teeth. The height the teeth protrude above the pitch circle is (called the addendum) is 1x the module and there is a tooth on each opposite side which makes the outside diameter equal the module x number of teeth +2 x module, which simplifies to module x no. teeth +2.

[@laurelgymnastics1634]

@@AndysMachines seems to me by that logic - the formula would be (OD-2)/N

[@MaddMart]

I think I'm missing something here. I have some old helical gears from a 1970s Triumph gearbox. I measured the OD of one of them (89.85mm.) and it has 33 teeth. That makes the Module = 2.567mm.. I take it that is the width of a tooth around the PCD? I've measured a tooth at the approx. PCD and it is 4.6mm.

[@AndysMachines]

The tooth pitch (one tooth+one space) is pi x module, which would be just over 8mm. One tooth width would be half of this, ~4mm, which is a lot closer to your measurement. It can be hard to estimate exactly where the PCD is so you might have measured slightly further down, it's a little above half the tooth depth. 2.567 module sounds like it's probably a 10DP gear (=2.54 module) or if it's likely to be metric then probably 2.5 module.

[@MaddMart]

@@AndysMachines Thanks Andy. The gearbox was derived from the earlier TRs so probably 1960s or even 1950s. I'm guessing we were using imperial measurements back then?

[@AndysMachines]

I'd guess imperial, but it could be either. 10DP and 2.5 mod are so close to each other though it might not make a difference.

[@HopeScreen]

same applies for a helical gear?

[@jerzykepinski]

wow this is good

[@velitom1160]

I also have a helical gear. o.d 39.25 helix angle 16 degrees, and 11 teeth. Does the profile shift factor affect the modulus of the gear? Best regards

[@HopeScreen]

I have gears files in STL format in CAd and i don't know what are its parameters? like the module, pitch etc

[@AndysMachines]

If you have an .stl you should be able to take measurements from it in the CAD program.