How to create a GT2 Timing Pulley in Fusion 360 - CAD Tutorial

[@nietaki]

I would have never guessed that when I find myself needing to design a custom GT2 Pulley in Fusion 360 someone will have already made a perfect video for me. The internet community is a beautiful thing. Thank you for making this!

[@CNCModellerUK]

Hi Nietaki, glad it's useful to you. Happy building! :-)

[@zforce69]

Great video, thanks for taking the time to make it. To all those reading that think this is too complex, it's not. the outcome is more than worth the time you invest.

[@CNCModellerUK]

Thanks for the positive feedback. Comments like this from are what keep me doing this :-)

[@kevinwilliams510]

I realize you posted this 5 years ago, but I only just needed to use it. I figured out why you had to fudge the transition between the R=1.00 and R=0.555 arcs and, consequently, why there were issues with circular patterns after changing the number of teeth. You used a fudge of 0.2*ToothAngle to replace the 0.40 mm horizontal distance between the centers of the two arcs. However, that creates too large of a distance to join the arcs when wrapping the tooth profile around a circle. So I found a better way to fix the center point of the R=1.00 arc to allow the two arcs to meet. With a flat profile, the distance between those centers is sqrt(0.4^2 + (ToothHeight-0.555)^2) = 0.445mm. So I created a point constrained to the circle at the top of the teeth and 0.445mm from the R=0.555 center and used that as the center of R=1.00 arc. That allowed those two arcs to be coincident and tangent without having to create an intermediate arc. It also allows me to scale the profile through a much larger range of tooth counts.

[@MultiBahader]

You really taught me how to create Pulley with zero knowledge of Fusion360.That really saved my life! thank you so much.

[@CNCModellerUK]

Glad it was helpful!

[@Golem_design]

Tho this is really helpful, I'm having trouble trying to not fall asleep watching this video.

[@TheSelfUnemployed]

Excellent guide sir! Even for someone who only has 2 Fusion 360 tutorials under my belt this was not to difficult to follow.

[@christianedelmann6880]

Extremely helpful and really helped me understand the general workflow of fusion. Thank you!

[@CNCModellerUK]

Glad you found it useful. Good luck with your projects! :-)

[@maximthemagnificent]

I learn best when doing an actual project and this video taught me a lot of Fusion 360 features I hadn't really needed yet. Thanks!

[@CNCModellerUK]

Hi Maximilian, glad you found it useful. Good luck with your future projects! :-)

[@sprobertson]

Thanks for actually describing all the dimensions! Was able to replicate this just the same in OnShape.

[@CNCModellerUK]

No worries Sean, glad it all worked out for you!

[@jafinch78]

I was just watching thinking I can do the same. Thanks again all!

[@CNCModellerUK]

Glad you found it useful! :-)

[@pidayrocks2235]

Absolutely incredible video! Thank you so much for this! It's exactly what I needed.

[@CNCModellerUK]

No worries. Glad it was useful! :-)

[@mtraven23]

thank you, this was a great help! I've gotta grind a tool to cut these, having a good model really helps. did run into an issue dropping to 16 teeth. I think you technically left the lengths of 3 of those arcs unrestrained, so when I scaled down, it drew crazy tangents. I just used another center circle to fix the length of the lower arc (0.90mm larger than root diam).

[@BrianBoniMakes]

Great video, learned so much. The first part I produced from this tutorial was better than about 7 test tries of my previous example.

[@CNCModellerUK]

Hi Brian, Thanks for the feedback, glad you found it useful! :-)

[@bears7777777]

To those having issues when changing the tooth count: When Fusion 360 does the "Combine" Operation, it does not combine any new teeth (e.g. made it a 30 tooth pulley, it will only combine the original 20 teeth). This causes the mirror operation to only operate on the combined body with only 20 of the teeth. I would recommend leaving the pulley width fixed, and the mirroring only the flanges, or just not mirroring at all. If you want to 3D print the pulley, make sure to combine everything manually before exporting so that the model is uniform.

[@swamihuman9395]

HERE'S THE 'FIX'... - Do 'Circular Pattern' on the 'Extrude/join' FEATURE, not on body. - Also, use 'Compute Option:Optimized'.

[@ericsherman8198]

Super helpful tutorial, 3d printed mine and it came out perfect. thanks!

[@CNCModellerUK]

No worries Eric. Glad it all worked out for You! :-)

[@joshlamont]

Thank you so much for this video! I learned so much!

[@CNCModellerUK]

Great news! I'm glad you found it useful 😁

[@ColinWatters]

Thanks for the useful vid.

[@CNCModellerUK]

Glad it was helpful!

[@seabeepirate]

I’ve been tinkering for years and never saw how powerful parameters were until now.

[@felicemorgigi1764]

Thanks for the great video! p.s.: you should become a dubbing artist with your voice haha

[@CNCModellerUK]

Thanks for the compliment lol. Glad you like the contents from more than one perspective!

[@glennrmarks]

The way you design your tooth assumes that the tooth distorts and flexes as much as the narrow part of the belt. But I would contend that the tooth stays rigid and only the thin part of the belt flexes (the part of least resistance). This would mean that you would design the cut out for the tooth as per spec from a straight line from tooth top to tooth top. What you define as the tooth top on a curved surface and rounded edges (shoulder radius) is difficult to say. Where you define it varies the depth you cut into the pully for the root radius of the tooth. I used the 1 mm transition radius minus 0.4 (because it starts 0.4 on the other side of center) i.e. 0.6 + 0.15 (shoulder radius) to give 0.75 (as a reference point). Looking at the tooth profile of a 15 tooth pully and a 60 tooth pully I was surprised to see a round-top on the teeth (no flat spot at all). When you flex a belt to a small diameter you see that the gap between teeth in the belt is almost round matching the tooth profile on a 15 tooth pully. I arbitrarily changed the shoulder radius to a formula that gives almost a round top tooth at 15 teeth and the original 0.15 radius at 300 teeth (to all intentions just like a strait belt) as follows (0.143 + (2.1 * (1 / number of teeth)). I used this formula multiplied by 0.8 + 0.6 as a multiplier to 1/2 the tooth angle to get an angle for a construction line. Where this line intersects the tooth height circle is the point I drew a straight line across. I then had a construction line (from the straight line across) going down the tooth height (0.75) to the bottom of the "root radius" circle and created a 2 point circle using this bottom point. The transition radius point also on this straight line across. By making the root radius ark, transition radius ark, shoulder radius ark, and the tooth height circle all coincident and tangential gives the finished profile. Your thoughts? (if only I could add a photo of the sketch to this comment) The center of the root radius is on the vertical line you used for the center of the tooth. This puts my completed tooth to the right of center after mirroring to the right using the tooth angle construction line as the mirror plane.

[@CNCModellerUK]

That's totally another conceptually valid approach. Personally I was looking for something that works, and under load the only really important aspect is the radius of the belt webbing and good engagement. The rubber teeth will compress to accommodate any errors and that compression should improve tooth location. I just used the simplest transformation that I could, that being Cartesian coordinates on the drawing to polar to wrap it around the pulley. Let me know how you get on with your approach. All the best Barry M

[@NBFL]

Well that's a convenient video. Thanks!

[@CNCModellerUK]

No worries, glad you found it useful!! :-)

[@goodboogie]

This is great. I need to build a ring with these GT2 teeth at a known diameter but an unknown number of Teeth. I suspect I'll just be able to change the parameters with a little math and should be able to work it out.

[@CNCModellerUK]

Glad you found it useful. Good luck with your project!

[@LuxorAB]

That's one awesome video, thanks man

[@CNCModellerUK]

Glad you found it useful! 👍

[@tikiss81]

Great video! Only one thing is not really clear and not nice (maybe it is not correct) how you connected the "Trans_Radius" to "Root_Radius" (with an undefined arc radius), I am not a professional but I think the "TransOffsetAngle" is not correct and that is why the two arcs are not crossing. The drawing has a parameter "b" which is 0,4mm, this is the distance between the center of "Trans_Radius" and "Root_Radius". If I measure it based on the "TransOffsetAngle" it is not 0,4mm. So I have deleted the "TransOffsetAngle" and constraint (Tangent and Coincident) the "Trans_Radius" and "Root_Radius". This will give a center distance of 0,399mm. What do you think?

[@CNCModellerUK]

Hi Tibor. Thanks for letting me know what you think. Without digging back into the CAD I'm not sure. However if you go back through the comments there was one that suggested some refinements. I also Posted an update video that might help too. kzbin.info/www/bejne/lZ6bdnlmoph2btU Good luck with your design!

[@min4ef]

Amazing video. I'm your admirer.

[@CNCModellerUK]

Thanks for the feedback, it's great to know you find my videos useful! Many thanks, Barry M

[@ramspantoja6197]

thank you so much for this video!!!

[@CNCModellerUK]

Glad you found it useful! :-)

[@jimmy2times]

Thanks indeed!

[@CNCModellerUK]

No worries. Glad you found it useful!

[@pablomunoz5776]

Great video, can you tell me, where you got the 0.2 to obtain TransOffsetAngle?

[@CNCModellerUK]

Hi Pablo, Glad you liked the video. It took me a while to figure out the 0.2 value myself from just looking at the footage, as I couldn't remember and it wasn't obvious to me either! The 0.2 value is the ratio between the tooth pitch (and hence angle) and the offset distance. 0.4/2 = 0.2. So the offset angle is 0.2 x the tooth angle. Hope that helps. All the best Barry M

[@downintheshop4147]

I'm getting a "compute failed" error when changing the tooth count. Is it possible to post a link to the f3d file to see if maybe I missed a step somewhere?

[@CNCModellerUK]

Hi @Down In The Shop, have you tried this fix? Hope it helps. kzbin.info/www/bejne/lZ6bdnlmoph2btU

[@rogerneumair170]

I tried the example and it is working fine. I ran into problems when trying to generate a pulley with more than 40 teeth. It says PulleyTeeth failed. PulleyTeeth is the name of the sketch generating the teeth. I have not done the combination of all the teeth to be more flexible in parameterizing the pulley. Any idea where this can come from?

[@CNCModellerUK]

Unfortunately I've not looked at this for a long time so I can't remember off the cuff. Sorry.

[@jesseb5378]

Excellent video! Might consider voice over though. Hard to understand you even with headphones on.

[@CNCModellerUK]

Thanks for the feedback. I'm hoping to get back to posting again soon so will keep that in mind. :-)

[@frandalzotto7244]

Hello, I have a problem to solve, it happens that I cannot find the table of measurements of the GT3 8M timing belt to be able to model a gearbox of an engine.Or simply tell me a way to model a pulley in Fusion 360 with the parameters that I want. you would help me a lot. Thank you

[@CNCModellerUK]

I assume a gt3 belt is a 3mm pitch... So you could try scaling the parameters accordingly?

[@frandalzotto7244]

@@CNCModellerUK In fact, it is 8mm pitch, so I can't find the required parameters, thank you very much in advance.

[@sentientproductions3281]

Great video! Thank you!

[@CNCModellerUK]

Glad you found it useful! 👍

[@neilfpv]

Amazing! I'll watch it again since I got lost on some areas. Sub'd too!

[@CNCModellerUK]

Thanks Neil, glad you found it useful! Thanks for the sub, it's the wonderful support from the community that keeps me coming back for more!

[@Experiment_UAE]

Thankyou very much

[@CNCModellerUK]

No worries, glad you found it useful!

[@weldchip]

thanks for this. really helped me out. is there a method to easily make the pulley bigger with more teeth but maintain the 2mm pitch? i tried messing about with the no of teeth in the parameters but it doesn't scale up correctly just by adding teeth to the parameters.

[@CNCModellerUK]

Hi Ash, No worries, glad you found it usefull. Fusion doesn't seem to like scaling the fillet between the root radius and the tip radius. If you remove that and change the parameter from memory it should scale properly. I just needed a very large gear 720t so I needed a really accurate design to make the belt fit over that nearly 650 teeth spread. good luck with your design. Cheers Barry M

[@lejF88]

@@CNCModellerUK Hi. I'm also having problems scaling this. Could you explain in more detail how to do what you wrote here?

[@CNCModellerUK]

Hi Lefe, I've been asked about this quite a lot recently so I'm going to create an addendum video to clarify what to do. Life has been a little chaotic recently but I hope to get it uploaded soon. Many Thanks Barry M

[@lejF88]

@@CNCModellerUK That's great! Thank you for going through the trouble

[@cubbucca]

Perfect

[@CNCModellerUK]

Thanks cubbucca! :-)

[@muchamadshofiudin9393]

i am sory, i want to ask how it can be simulate with belt?

[@CNCModellerUK]

Hi, To be honest I've not thought about it. You could use the same principle to draw the belt wrapped around the pulley and then use the belt drawing for the links between pulleys. You could also use joints in fusion to let the pulley rotate but I don't think you could simulate the belt moving too. Hope that helps! All the best Barry M

[@laurakiasgreece]

How can i find what type of drive belt is the 59c-46241-00 drive belt ( this is yamaha part code)

[@CNCModellerUK]

Hi I, sorry I don't know much about motorcycle drive belts. Google is your friend! Best of luck!

[@sentientproductions3281]

Circumference?

[@Fexer441]

Thank You!

[@CNCModellerUK]

You're welcome!

[@gigglesmclovin]

can someone please share a file with the final result in it?

[@kylekirchen2205]

where did you get the canvas?

[@CNCModellerUK]

Hi Kyle, I just searched on Google for GT2 timing belt dimensions... Hope that helps. :-)

[@cshort42]

Help: Does anyone have the drawings for a GT5 timing pulley ?

[@CNCModellerUK]

Sorry I don't. Google is your friend...

[@olenorgren7915]

16:34-16:38 Tea is ready!

[@CNCModellerUK]

Lol! :-)

[@MC-xg9fv]

This is incorrect. GT2 belt profile is different to pulley profile.

[@CNCModellerUK]

Hi MC thanks for the feedback, that may be the case. However this profile works perfectly for any pulley size I've tried, so is good enough for me! If you have a link to the specification for a pulley feel free to leave it in a comment below. Cheers, Barry M

[@CNCModellerUK]

Hi All, I've posted a short update to help with changing the number of teeth of the pulley.The latest version of the file I'm using seems to be working OK now. Not sure if its a Fusion update or if I changed something but the fix in the video is what I used to have to do too. The update to this video will be released on Friday the 31st Jan 2020 here: kzbin.info/www/bejne/lZ6bdnlmoph2btU , Patreon supporters have early access now.

[@cyberstar251]

i can barely hear what your saying.

[@CNCModellerUK]

Thanks for the input. I've had that feedback before. Hopefully my latest videos are better.

[@Addepat]

youre talking to yourself, not to listeners...hardly to understand what youre saying...

[@yusufkor5900]

Snail speed...

[@CNCModellerUK]

Thanks for the feedback but I'm not sure what you mean!