Thank you so much for this great tutorial. I'm really glad to learn the equation driven function for drawing the involute, instead of drawing numerous tangent lines and confusing myself. You've helped me out so much!
Thank you so much for this. Absolutely spectacular. I'm using this to make a clock, and I found that by simply inputting "N" for the number of instances in the circular pattern you can have it auto update. Also, I made the diametral pitch dependent on the pitch diameter via adding another variable. Just a couple things to make changing gear sizes easier.
Matthew Miller I'm using SDW 2014, not sure if it will work on older versions. I simply put "N" (without quotes) into the field "Number of Instances" when I did the circular pattern. This way I can make a bunch of different size gears without having to update the number of teeth in the equations AND the circular pattern. As for the pitch diameter, I just made another variable (named pitchdia I think) and changed the value for "P" to an equation based on "pitchdia." This really doesn't solve anything for most practical uses, but when you're making a bunch of different sized gears, it shaves a minute or two off each one.
Super helpful video. Some advice would be set the number of instances of your circular pattern to "n" and the fillet to a fraction of "c" (for example he used R.10 with a .125 clearance, so you could set your fillet to 4/5*"c") to ensure it will never be larger.
Great tutorial, sir! Just one note: when creating the circular pattern, one might need to be sure to have the "Geometry pattern" checkbox checked in the circular pattern dialog box, otherwise it might not let one propagate the fillet as well
Damn it. I just lost an hour erasing and redoing everything step by step. I was going crazy until I figured it out on my own.... I was going nuts! Now that I'm reading your comment I feel trolled xD BTW great tutorial Yang Cao, but you should have used an equation in the circular pattern, that's pretty obvious. So you don't have to manually adjust it every time. Number of patterns must be equal to "N". Same thing for the fillets, you could have used an equation like "fillet radius equals 0.5*clearance" or sth like that.
Thank you so much! I am helping a client design a machine utilizing a few existing parts and needed to create gears with a dimetral pitch of 4.62. I couldn't make it work, but with this, it was a breeze!
Hello, thanks very much, you saved my life :D Just a suggestion, to automatic define the root fillet, i used 0.8*c, so we got 80% of clearance (a safe value).
Thank you for sharing! Note: to write equation you may need to write with " " the variables. Improvements: - Number of tooth can be linked to the circular pattern instances - Fillet radius can be setted as Diameral Pitch / 10, this prevent manual adjust - Alpha calculation is not required, simply link the line to the intersection with Diametral pitch, than simpler equation as 360/4/N. - Not necessary to write two equation, can be used one than mirror it
This is fantastic! I was able to follow along using OpenSCAD instead of Solidworks because of how detailed your explaination was. It also cleared up a bunch of questions I had regarding gears in general. Thanks for sharing!
Hello, I very much enjoyed your presentation and demo, excellent, you kindly explained all the steps and it was relatively easy to follow, much appreciated. Thanks.
Dr. Cao, thanks for posting this! Now to find out why Solidworks fails at 39 teeth (when the dedendum circle diameter is greater than the base circle diameter).
+tobyteddy222, nope, I have not figured out why. I have contacted my reseller and they said that they are looking into it, I sent them my part file. I think that it has something to do with base circle being a smaller diameter than the dedendum circle. If you look at the results of 39 teeth, you'll see that the tooth base produces "notches" with the involutes. Trimming the dedendum circle and each involute turns one of the involutes red and the "The sketch has not been undated..." message is displayed. I will post any resolution when I get it.
+tobyteddy222, I still haven't received a reason why this fails but have developed a work around: 1. Open an new sketch on the same plane as that which holds the equation driven involutes. 2. Select the involutes and the base (dedendum) circle. 3. Click Convert Entities. Those features are now copied onto the new sketch with no equation driven relations between them. They can now be trimmed as required so that you can use the new sketch to Extrude Cut the disc. After you extrude cut, simply create a Circular Pattern using that Cut-Extrude feature and you're done! You can now create spur gears of any number of teeth up to 105. There is a problem with this method because 360/(4*N)-alpha equals zero when N = 105.3916. So, gears with 106 and more teeth will fail.
This was an excellent lesson. I managed to create this in AutoCAD INVENTOR. If anyone needs the Equation Formula for INVENTOR, I've listed them below. INVENTOR is very particular about the syntax and unit parameters: BaseCircleDiameter / 2 ul * ( cos(1 rad * t) + t * sin(1 rad * t) ) BaseCircleDiameter / 2 ul * ( sin(1 rad * t) - t * cos(1 rad * t) ) BaseCircleDiameter / 2 ul * ( cos(1 rad * -t -2 * BaseCircleDiameter / 1 in * 3.14159265359/180) - t * sin(1 rad * -t-2 * BaseCircleDiameter / 1 in * 3.14159265359/180) ) BaseCircleDiameter / 2 ul * ( sin(1 rad * -t -2 * BaseCirceDiameter/ 1 in * 3.14159265359/180) + t * cos(1 rad * -t-2 * BaseCirceDiameter/ 1 in * 3.14159265359/180) ) tmin = 0.00001 tmax = 0.68
I just wanna thank you for this, this is an incredibly helpful tutorial and your other videos are very helpful as well. You're a fantastic professor. I wish SolidWorks had a gearing tool though. Also, it would be helpful if you could speak up a little bit in your videos.
In SW 2013 if you double click the pattern and edit the dimension in the view window, you can enter the global variable there. This also works for helix.
he chose 0.68 so he can put bounds on the curve of that first involute line, otherwise it would keep plotting for all infinite points of t (reference for anyone else wondering)
this determines the length of the curve from the start . it is the end point of the curve. it just needs to be long enough to go past the outer edge of the gear body so you can trim it later. type 2.00 in that field and you will see what happens.
Equation Driven Curve: "D2@Sketch2" - Circle Name from which is shape created "D2@Sketch2"*.5*(cos(t)+t*sin(t)) "D2@Sketch2"*.5*(sin(t)-t*cos(t)) Mirrored Curve: "D2@Sketch2"*.5*(cos(-t-2*"D4@Sketch2"*pi/180)-t*sin(-t-2*"D4@Sketch2"*pi/180)) "D2@Sketch2"*.5*(sin(-t-2*"D4@Sketch2"*pi/180)+t*cos(-t-2*"D4@Sketch2"*pi/180)) Remember you need to be in Sketch2 to make it work.
Awesome tutorial! I think you can also drive the fillet and circular pattern using equations. That would make it a little more time saving. Thanks again for this tutorial! =)
great job displaying the exact equations necessary to produce a gear that can be changed with only a couple variables. Could you produce a video teaching us how to build equation driven helical bevel / miter gears?
Hello Sir, can you please make a video on internal spur gear involute shape as well? I am struggling to design it. It will be very helpful for me in my research field
Dr Yang, really helpful video. Question from my side (couple of years after your video and the majority of the responses) But, can you please describe / explain why are you using "t2=0.68" which such value? I've reviewed your material, and I don't see, yet, the correlation Could you please help me to understand? Thanks
I played with it. I could be totally wrong but I think t2=.68 just guarantees the involute curve will extend past the addendum circle diameter. Like if you made both t2s=.75, the gear would still be exactly the same.
Thanks for uploading this, it really helped me understand the process a lot more. I have made my version of your model, are there any conditions that need to be modified to account for a much larger spur gear? I am trying to model the angle but my value comes back as a negative value and cannot define the angle. Diametral Pitch = 0.3333 No of teeth = 110 Pressure angle = 20° Addendum Diameter = 336mm Pitch Diameter = 330mm Base Circle = 322mm Dedendum Diameter = 322.8mm My tan and beta angle values in the involute curve come back with a value of -0.3° Has anyone used this to create a relatively large spur gear?
Thanks a lot for this awesome tutorial. Till now, it is the best one with scientific basis. The voice is clear, the accent is very good, and referring to lecture is very nice. Can you please tell me why the "base circle diameter=Pitch circle diameter*cos(Phi)"?
khkgears.net/new/images/basic_gear_terminology_and_calculation/Fig.-2.6-Working-Gear-Nomenclature.jpg This is the link to a picture, on which you'll see that it's a simple right-angled triangle
I really appreciate your effort. I am just beginner of solidworks and followed your lecture and got it. As you mentioned I encountered the base circle diameter is smaller than dedendum circle diameter. Do you have other lecture for this or should I draw from the beginning? Please let me have your tip for this. Thanks in advance
why does this don't work when I go to more teeth? it collapses in 42 teeth. the dedendum circle becomes bigger than the base circle and it doesn't work. it is a great tutorial but I've been struggling with this all day long...
it probably has to do with the pressure angle you're working with. remember that if we want to constrain the dedendum and base circles, we can express their relationship as: (pitch diam) - 2(dedendum) < (base diam) with pitch diameter equal to (module)*(num of teeth), or (num teeth)/(diametral pitch) and base diameter equal to (pitch diameter)*cos(pressure angle), just like the textbooks give us. you can solve for your max number of teeth by moving all other variables to the opposite side, but you should see that the num of teeth at 20 degrees pressure angle is mathematically limited to like 41 or something.
Thanks for the demo. I noticed on SW14, that for the circular pattern, I was able to set the number of instances to be the global variable N so it auto updates. Also the fillet radius can be set to "c" / 3 or 4 or whatever.
Very nice tutorial Mr Cao, I have a question, do you know, how to design a rack and pinion (obviously I learned how to do a pinion), but I cannot to draw a rack to matching pinion with, I will be very happy, If you could do that. Thank you very much.
Hi Dr Yang Cao, Thanks for the video! it help a lot, but I noticed the link for the tutorial file isn't working any more, I wonder where I can download it again, it's very good information.
Very usefull material. Thanks a lot. When you say "a" need to hear "b" as well. Don't you have a tutorial for internal involute gear too? Hot to direct involute curve toward center now?
Hello Mr. Cao. I am trying to create my initial equations just like you do on the video. However, I am not able to do so. After I enter the Global Variable name I press enter and continue to the Value/Equation area. Once there, I enter the value I want and press enter, but it does not accept the value. I cannot continue beyond that point. Hope you can make a suggestion to my problem. Thank you in advance.
Great video. Used this information to make a template using a design table for not only spur but helical gears as well. The only thing I am unsure of is what determines what the clearance, or fillet radius, is. Does anyone have any knowledge of this?
If you're referring to the *180/pi, this is the conversion from radians to degrees. This is here because the equation calls for radians, (notice "phi rad"), however our pressure angle is in degrees
thnk u for the video, my problem is with m=2.5 angle pressure 20 ans nbr of teeth 45 the base diametre is higher than the dedundum cercle diameter how can i solve this please
Hi and thanks for sharing this great tutorial! It has been very helpful. Can I ask, is this gear design based on a "zero backlash" basis? And if so, how would you recommend building in backlash? Is there way to do it using global variables such as modifying the pitch circle diameter or module etc? Many thanks again!
Great video! Helped me a lot. Just one comment. When you named your global variables, you called "P" Diametral pitch but I think that should be the pitch diameter (in) and you called "dp" pitch diameter when that should be diametral pitch(teeth/in). The values are correct though. Thank you so much for your help.
One mistake that I noticed is during the circular patterning of the filet and extruded cut. The number of instances should be set to the global variable "N" rather than the number 20 which is shown.
to clarify.. when you input your equation curve, the genereated curve goes from left to right...0 degrees, to the right, with the given equation... my line goes up... from 0 degrees, vertical...I have No idea why its doing this. I even went back and did it with all your numbers..
Thank you for this video. Is there a way where I can dictate the addendum circle diameter? I am trying to remake a gear I currently have that has a addendum circle diameter of .94454 with a diametral pitch of 24, 42 teeth, and pressure angle of 20deg. Thank you
hello, nice video,first i modeling 2 gear but i have a probleme for collision when i want to assemblate them, why ? the second, i want to simulate stress gear, how can i do it ? thank you very much
This video worked out great for my except for one thing. When I finished my gear even though I had an N of 21 I ended up having 24 gear teeth. I noticed that on yours too you ended up having 20 gear teeth when you finished your circular pattern. Is there anyway to fix that?
I followed your instructions.. just putting in my own numbers for the variables at the beginning... and my first equation curve is completely wrong. im not sure why. sw 2016
Hello! Excellent tutorial! I am running into one issue though with the Phi value. I can change N and P to all the combinations I need without issue, but when I change Phi to 30 degrees I get a Dedendum circle that is larger than the base circle and the pattern won't cut. Any advice on how to fix this? I am trying to draw a 5/10 36T 30deg involute gear.
Thanks for the great tutorial. I`m just confuse why do you need to create the second involute? when i tried to mirror the first involute using a quarter of angular circular pitch, the result was the same.
+francis wayne mojana, it doesn't work properly if you simply mirror. It does work for the very first gear you create, but when you change the number-of-teeth variable and rebuild, you'll notice that the tooth profile is wrong. You need both sets of parametric equations for this to work as a template for creating other gears.
Hi Dr Yang Cao, i did succesfully created a pinion with N= 36 Teeth , Moudle= 1.25, with P=0.8 . However when creating the Gear of N=108 Teeth (3:1) ratio, i had a problem with beta angle as it turn to be negative and this cannot be accepted in solidworks , so resulted in a different involute profile for the gear ?. How to solve this problem? and what angle beta should be used for the gear. i would really appreciate your help. Cheers
Does anyone know how to do this with SW2007? I can work out the equation feature differences, but this version does not have the Equation Driven Curve feature. Any ideas?
Personally it's a bit difficult to create a spur gear in this wat. Rather than using your toolbox, and using any spur gear in there.. I can see the use for this, if you want to create some type of special gear, that does not exist in the toolbox. Other than that, this will be too time consuming.
when dedendum lies above base circle, i found an interesting thing. involute profile generated from base circle cuts pitch circle somewhere between addendum circle. Would you please help me through this problem?
I have the same problem. But I guess you will have to change the sketch for these cases. My solution was to make the base at dedendum, in which case the fillet would be between dedendum circle and the involute curve.
Wow, wish I had Dr. Cao as my professor. What an excellent demonstration and accompanying material. Thank you for making this accessible to everyone!
Thank you so much for this great tutorial. I'm really glad to learn the equation driven function for drawing the involute, instead of drawing numerous tangent lines and confusing myself. You've helped me out so much!
Thank you so much for this. Absolutely spectacular. I'm using this to make a clock, and I found that by simply inputting "N" for the number of instances in the circular pattern you can have it auto update. Also, I made the diametral pitch dependent on the pitch diameter via adding another variable. Just a couple things to make changing gear sizes easier.
Can you explain why you made the diametrical pitch dependent on the pitch diameter? What does this solve?
Matthew Miller I'm using SDW 2014, not sure if it will work on older versions. I simply put "N" (without quotes) into the field "Number of Instances" when I did the circular pattern. This way I can make a bunch of different size gears without having to update the number of teeth in the equations AND the circular pattern. As for the pitch diameter, I just made another variable (named pitchdia I think) and changed the value for "P" to an equation based on "pitchdia." This really doesn't solve anything for most practical uses, but when you're making a bunch of different sized gears, it shaves a minute or two off each one.
Super helpful video. Some advice would be set the number of instances of your circular pattern to "n" and the fillet to a fraction of "c" (for example he used R.10 with a .125 clearance, so you could set your fillet to 4/5*"c") to ensure it will never be larger.
Great tutorial, sir!
Just one note: when creating the circular pattern, one might need to be sure to have the "Geometry pattern" checkbox checked in the circular pattern dialog box, otherwise it might not let one propagate the fillet as well
Damn it. I just lost an hour erasing and redoing everything step by step. I was going crazy until I figured it out on my own.... I was going nuts! Now that I'm reading your comment I feel trolled xD
BTW great tutorial Yang Cao, but you should have used an equation in the circular pattern, that's pretty obvious. So you don't have to manually adjust it every time. Number of patterns must be equal to "N". Same thing for the fillets, you could have used an equation like "fillet radius equals 0.5*clearance" or sth like that.
You are a gentleman and a scholar. Thank you so much for this comment.
I had an issue with that, but I changed my fillet so that it was included in the sketch, and then set it to an equation.
Thank you sir. True legend lol
thanks alot for this
Thank you so much! I am helping a client design a machine utilizing a few existing parts and needed to create gears with a dimetral pitch of 4.62. I couldn't make it work, but with this, it was a breeze!
I wish, I had lectures like these 10 years ago in university. Great tutorial! Thank You!
Your video has certainly helped my team design our own gears for a design project. Your video is very clear and concise. Thank you Sir.
Hello, thanks very much, you saved my life :D
Just a suggestion, to automatic define the root fillet, i used 0.8*c, so we got 80% of clearance (a safe value).
Thank you for sharing!
Note: to write equation you may need to write with " " the variables.
Improvements:
- Number of tooth can be linked to the circular pattern instances
- Fillet radius can be setted as Diameral Pitch / 10, this prevent manual adjust
- Alpha calculation is not required, simply link the line to the intersection with Diametral pitch, than simpler equation as 360/4/N.
- Not necessary to write two equation, can be used one than mirror it
Circular pattern when linked revert back to same value any idea
Why pattern 20 when he got 18 teeth? it happened to me when i designed my gear (different characteristics)
This is fantastic! I was able to follow along using OpenSCAD instead of Solidworks because of how detailed your explaination was. It also cleared up a bunch of questions I had regarding gears in general. Thanks for sharing!
Great tutorial. This video captures the difference between hobbyist level CAD and actual mechanical engineering XD
Thanks Yang, the tutorial is detailed and easy to follow. Save me tons of time!.
Hello, I very much enjoyed your presentation and demo, excellent, you kindly explained all the steps and it was relatively easy to follow, much appreciated. Thanks.
Thanks for putting together this video, really appreciate it. Comprehensive and easy to understand.
Dr. Cao, thanks for posting this! Now to find out why Solidworks fails at 39 teeth (when the dedendum circle diameter is greater than the base circle diameter).
+Jeff Biss
Have you, by any chance, figured out yet why it fails at 39 teeth? I'm experiencing the same problem.
+tobyteddy222, nope, I have not figured out why. I have contacted my reseller and they said that they are looking into it, I sent them my part file. I think that it has something to do with base circle being a smaller diameter than the dedendum circle. If you look at the results of 39 teeth, you'll see that the tooth base produces "notches" with the involutes. Trimming the dedendum circle and each involute turns one of the involutes red and the "The sketch has not been undated..." message is displayed. I will post any resolution when I get it.
+tobyteddy222, I still haven't received a reason why this fails but have developed a work around:
1. Open an new sketch on the same plane as that which holds the equation driven involutes.
2. Select the involutes and the base (dedendum) circle.
3. Click Convert Entities. Those features are now copied onto the new sketch with no equation driven relations between them. They can now be trimmed as required so that you can use the new sketch to Extrude Cut the disc. After you extrude cut, simply create a Circular Pattern using that Cut-Extrude feature and you're done!
You can now create spur gears of any number of teeth up to 105. There is a problem with this method because 360/(4*N)-alpha equals zero when N = 105.3916. So, gears with 106 and more teeth will fail.
Very good work. I have now a complete parametric gear !
Thank you very much !
This was an excellent lesson. I managed to create this in AutoCAD INVENTOR. If anyone needs the Equation Formula for INVENTOR, I've listed them below. INVENTOR is very particular about the syntax and unit parameters:
BaseCircleDiameter / 2 ul * ( cos(1 rad * t) + t * sin(1 rad * t) )
BaseCircleDiameter / 2 ul * ( sin(1 rad * t) - t * cos(1 rad * t) )
BaseCircleDiameter / 2 ul * ( cos(1 rad * -t -2 * BaseCircleDiameter / 1 in * 3.14159265359/180) - t * sin(1 rad * -t-2 * BaseCircleDiameter / 1 in * 3.14159265359/180) )
BaseCircleDiameter / 2 ul * ( sin(1 rad * -t -2 * BaseCirceDiameter/ 1 in * 3.14159265359/180) + t * cos(1 rad * -t-2 * BaseCirceDiameter/ 1 in * 3.14159265359/180) )
tmin = 0.00001
tmax = 0.68
屏幕录像专家。。。记得当时看黑客视频就是用这个软件。
现在在油管上看到了，满满的回忆啊
I just wanna thank you for this, this is an incredibly helpful tutorial and your other videos are very helpful as well. You're a fantastic professor. I wish SolidWorks had a gearing tool though. Also, it would be helpful if you could speak up a little bit in your videos.
In SW 2013 if you double click the pattern and edit the dimension in the view window, you can enter the global variable there. This also works for helix.
This is an amazing tutorial, thank you very much for taking the time to make it and sharing it with the world!
Well, that's about as good a demo as can be done. Nice job, sir. And thanks for a solid technique.
Thank you so much!! I needed to crank up a bit but it was totally worth it!
Im so happy I can make gears now!!!!
Excellent video - very helpful. One question though. At 9:45 you enter 0.68 into the T2 field. What does this value represent, and how is it derived?
That is just a value for "t" I randomly selected after a few trial.
he chose 0.68 so he can put bounds on the curve of that first involute line, otherwise it would keep plotting for all infinite points of t (reference for anyone else wondering)
this determines the length of the curve from the start . it is the end point of the curve. it just needs to be long enough to go past the outer edge of the gear body so you can trim it later. type 2.00 in that field and you will see what happens.
finally sb who knows his shit. though those long ass equations in the notepad could be given in desription to copy
It basically saved my life thanks sir
Thank you so much sir!! I m really greatful!!
Do you have similar explaination for Internal Spur Gear Modeling?
Nice info,thanks for sharing it with us, well done :)
Equation Driven Curve:
"D2@Sketch2" - Circle Name from which is shape created
"D2@Sketch2"*.5*(cos(t)+t*sin(t))
"D2@Sketch2"*.5*(sin(t)-t*cos(t))
Mirrored Curve:
"D2@Sketch2"*.5*(cos(-t-2*"D4@Sketch2"*pi/180)-t*sin(-t-2*"D4@Sketch2"*pi/180))
"D2@Sketch2"*.5*(sin(-t-2*"D4@Sketch2"*pi/180)+t*cos(-t-2*"D4@Sketch2"*pi/180))
Remember you need to be in Sketch2 to make it work.
Great Work Many thanks
Do you have vedio on helical gear tooth cut ..like you showed on spur gear
This is best video about gears in SW! Pro. Thank you!
Awesome tutorial! I think you can also drive the fillet and circular pattern using equations. That would make it a little more time saving. Thanks again for this tutorial! =)
This method looks pretty strong
Excellent video
Thank you my Teacher
great job displaying the exact equations necessary to produce a gear that can be changed with only a couple variables.
Could you produce a video teaching us how to build equation driven helical bevel / miter gears?
Hello Sir, can you please make a video on internal spur gear involute shape as well? I am struggling to design it. It will be very helpful for me in my research field
Dr Yang, really helpful video. Question from my side (couple of years after your video and the majority of the responses)
But, can you please describe / explain why are you using "t2=0.68" which such value?
I've reviewed your material, and I don't see, yet, the correlation
Could you please help me to understand?
Thanks
I played with it. I could be totally wrong but I think t2=.68 just guarantees the involute curve will extend past the addendum circle diameter. Like if you made both t2s=.75, the gear would still be exactly the same.
Thank you for the post! Helped me immensely!
Thanks for uploading this, it really helped me understand the process a lot more.
I have made my version of your model, are there any conditions that need to be modified to account for a much larger spur gear? I am trying to model the angle but my value comes back as a negative value and cannot define the angle.
Diametral Pitch = 0.3333
No of teeth = 110
Pressure angle = 20°
Addendum Diameter = 336mm
Pitch Diameter = 330mm
Base Circle = 322mm
Dedendum Diameter = 322.8mm
My tan and beta angle values in the involute curve come back with a value of -0.3°
Has anyone used this to create a relatively large spur gear?
I really love it, job well done!!! You have won a new subscriber :)
thanks for the tutorial, very good! Can you give me a solution for a number of teeths >420 and metric module 4?
Very helpful video. Thank you very much!
Great video sir!
THANKS a bunch from australia :)
Unreal tutorial! Thank you so much!
Great tutorial, but wouldn't be easier to make the second involute curve as a symmetry from the first one (via the constrution line)?
Would it be possible to mirror the second involute istead of using another parametric curve?
Thanks a lot for this awesome tutorial. Till now, it is the best one with scientific basis. The voice is clear, the accent is very good, and referring to lecture is very nice. Can you please tell me why the "base circle diameter=Pitch circle diameter*cos(Phi)"?
khkgears.net/new/images/basic_gear_terminology_and_calculation/Fig.-2.6-Working-Gear-Nomenclature.jpg
This is the link to a picture, on which you'll see that it's a simple right-angled triangle
Thanks a lot Mr. Yang Cao.
I really appreciate your effort. I am just beginner of solidworks and followed your lecture and got it. As you mentioned I encountered the base circle diameter is smaller than dedendum circle diameter. Do you have other lecture for this or should I draw from the beginning? Please let me have your tip for this. Thanks in advance
why does this don't work when I go to more teeth? it collapses in 42 teeth. the dedendum circle becomes bigger than the base circle and it doesn't work. it is a great tutorial but I've been struggling with this all day long...
thats bad
it probably has to do with the pressure angle you're working with. remember that if we want to constrain the dedendum and base circles, we can express their relationship as:
(pitch diam) - 2(dedendum) < (base diam)
with pitch diameter equal to (module)*(num of teeth), or (num teeth)/(diametral pitch) and base diameter equal to (pitch diameter)*cos(pressure angle), just like the textbooks give us.
you can solve for your max number of teeth by moving all other variables to the opposite side, but you should see that the num of teeth at 20 degrees pressure angle is mathematically limited to like 41 or something.
Awesome tutorial. Thanks!
Well this is way above my level, probably I will just guess the dimensions of my gears.
Thank you so much for this sir !! this is Absolutely well done and very helpfull !!
Thanks for the demo. I noticed on SW14, that for the circular pattern, I was able to set the number of instances to be the global variable N so it auto updates. Also the fillet radius can be set to "c" / 3 or 4 or whatever.
Good to know. Thanks for the information.
Very nice tutorial Mr Cao, I have a question, do you know, how to design a rack and pinion (obviously I learned how to do a pinion), but I cannot to draw a rack to matching pinion with, I will be very happy, If you could do that. Thank you very much.
Fantastic tutorial
Hi Dr Yang Cao, Thanks for the video! it help a lot, but I noticed the link for the tutorial file isn't working any more, I wonder where I can download it again, it's very good information.
Very good! Two question. The parametric part remains blue is it still undefined then?
Very usefull material. Thanks a lot. When you say "a" need to hear "b" as well. Don't you have a tutorial for internal involute gear too? Hot to direct involute curve toward center now?
Hello Mr. Cao. I am trying to create my initial equations just like you do on the video. However, I am not able to do so. After I enter the Global Variable name I press enter and continue to the Value/Equation area. Once there, I enter the value I want and press enter, but it does not accept the value. I cannot continue beyond that point. Hope you can make a suggestion to my problem. Thank you in advance.
Excellent video
Great video. Used this information to make a template using a design table for not only spur but helical gears as well. The only thing I am unsure of is what determines what the clearance, or fillet radius, is. Does anyone have any knowledge of this?
Hi there, on your notepad, the alpha equation is different than shown on the PDF. It is wrong?
If you're referring to the *180/pi, this is the conversion from radians to degrees.
This is here because the equation calls for radians, (notice "phi rad"), however our pressure angle is in degrees
Can u make the same tutorial for Bevel Gears? Thanks.
any odds you could make the drive public?
thnk u for the video, my problem is with m=2.5 angle pressure 20 ans nbr of teeth 45 the base diametre is higher than the dedundum cercle diameter how can i solve this please
Thank you so much man
Thank you soooo much.....it was very helpful....😃
Hi and thanks for sharing this great tutorial! It has been very helpful.
Can I ask, is this gear design based on a "zero backlash" basis? And if so, how would you recommend building in backlash? Is there way to do it using global variables such as modifying the pitch circle diameter or module etc?
Many thanks again!
Great video! Helped me a lot. Just one comment. When you named your global variables, you called "P" Diametral pitch but I think that should be the pitch diameter (in) and you called "dp" pitch diameter when that should be diametral pitch(teeth/in). The values are correct though. Thank you so much for your help.
this is the best. It helps. Thanks
One mistake that I noticed is during the circular patterning of the filet and extruded cut. The number of instances should be set to the global variable "N" rather than the number 20 which is shown.
The old version of SolidWorks does not allow to do that.
I am using solid works 2016, and when I set the number of instances to global variable N it simply substitutes the current value
For number inside of the circular pattern could you not just call the variable "number or teeth"?
Hello Sir, Kindly provide me access to the drive file... Thank You !
to clarify.. when you input your equation curve, the genereated curve goes from left to right...0 degrees, to the right, with the given equation... my line goes up... from 0 degrees, vertical...I have No idea why its doing this. I even went back and did it with all your numbers..
I made the same mistake. You probably wrote the Y(t) equation wrong. My error was putting a plus instead of a minus lol
Have you tried to build a non circular gear with involute teeth? Something like gearify but with involute teeth. Would be great!
where does the 0.68 come from in the involute curve parametric equation
while draw the equation driven curve, how did you come up with t = 0.68
See Chad Wassink's comment below: Yang Cao replied "That is just a value for "t" I randomly selected after a few trial. "
@@harmonytan6746 Lmao. I was just wondering about that
Thank you for this video. Is there a way where I can dictate the addendum circle diameter? I am trying to remake a gear I currently have that has a addendum circle diameter of .94454 with a diametral pitch of 24, 42 teeth, and pressure angle of 20deg. Thank you
Great job sir!
hello,
nice video,first i modeling 2 gear but i have a probleme for collision when i want to assemblate them, why ?
the second, i want to simulate stress gear, how can i do it ?
thank you very much
How do you create a curve with profile shift?
This video worked out great for my except for one thing. When I finished my gear even though I had an N of 21 I ended up having 24 gear teeth. I noticed that on yours too you ended up having 20 gear teeth when you finished your circular pattern. Is there anyway to fix that?
Thanks
Can I add the module in the equations instead of updating manually??
And add also the relation between module and number of teeth and the pitch??
I followed your instructions.. just putting in my own numbers for the variables at the beginning... and my first equation curve is completely wrong. im not sure why. sw 2016
Could you provide the information on how to obtain alpha? Thanks
Hello! Excellent tutorial! I am running into one issue though with the Phi value. I can change N and P to all the combinations I need without issue, but when I change Phi to 30 degrees I get a Dedendum circle that is larger than the base circle and the pattern won't cut. Any advice on how to fix this? I am trying to draw a 5/10 36T 30deg involute gear.
I find my solution thank you:)
Thanks for the great tutorial. I`m just confuse why do you need to create the second involute? when i tried to mirror the first involute using a quarter of angular circular pitch, the result was the same.
+francis wayne mojana, it doesn't work properly if you simply mirror. It does work for the very first gear you create, but when you change the number-of-teeth variable and rebuild, you'll notice that the tooth profile is wrong. You need both sets of parametric equations for this to work as a template for creating other gears.
Hi Dr Yang Cao, i did succesfully created a pinion with N= 36 Teeth , Moudle= 1.25, with P=0.8 . However when creating the Gear of N=108 Teeth (3:1) ratio, i had a problem with beta angle as it turn to be negative and this cannot be accepted in solidworks , so resulted in a different involute profile for the gear ?. How to solve this problem? and what angle beta should be used for the gear. i would really appreciate your help.
Cheers
Great work Sir
I am having problem in calculating "alpha", with same values my alpha values turned out to be -1.37
Did you forget the square root?
@@arvindmahadevan9337 no
Does anyone know how to do this with SW2007? I can work out the equation feature differences, but this version does not have the Equation Driven Curve feature. Any ideas?
Personally it's a bit difficult to create a spur gear in this wat. Rather than using your toolbox, and using any spur gear in there.. I can see the use for this, if you want to create some type of special gear, that does not exist in the toolbox. Other than that, this will be too time consuming.
How can I alter this to make less than 13 teeth possible?
Can you please provide the document
when dedendum lies above base circle, i found an interesting thing. involute profile generated from base circle cuts pitch circle somewhere between addendum circle. Would you please help me through this problem?
I have the same problem. But I guess you will have to change the sketch for these cases. My solution was to make the base at dedendum, in which case the fillet would be between dedendum circle and the involute curve.
Yucel Sert This isn't a good idea because having a base of the wrong size will lead to improper geometry.
simplification: alpha = tan(phi)-phi or ?
what about profile shift?
Hi, how to use auto double quote with equation?