Should you join a chain gang?

Anyone try silent chains? Ramsey Products | Silent chain for power transmission and conveying overview

Locking bushings are nice. No need for a key way.

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Hello All
Thank You a lot for this article and comments. Iam mechanical designer and my next build will be on chain. Based on this I refreshed my university education and made some research with basic calculations. Please check it, mainly chain riders and please let me know Your feedback on this theory.

At first european 05B are more or less in the same strength category like ASA25 and 06B is equal to ASA35H. What is very iportant for us is the pitch of chain which is together with tooths define diameters of sprocket. And diameter on wheel should be so small as is possible ,to have enought space out of road. On the other side, motor sprocket should be so big as is possible to avoid “polygon effect”. See fallowing link. Sprocket Design Tutorial - CAD - Chief Delphi
Therefore in case that You would like to have fast board (slighly more than 50km/h) and still usefull torque , my recomandation is to choose motor with low kv and gear ratio aroun 1:3. For efample 140kv and 10:36 (or 9:35)with 06B chain.
In industry , to have long chain life, motor sprocket should have odd number of tooths and wheel sprocket even number of tooths. Reason is to have equal abrasion for complet setup. I do not want to put all rules here, You can check Your gear ratio here: ⚡Chain and Sprocket Calculator | RPM and Chain Speeds

Iam already made few of calculation. I would like to use motor Flipsky 6374 140kv 3,5kW. This motor have max. torque 8N/m. My targer was to use ASA25H chain becouse of small pitch, unfortenatly with this motor Iam slighly cross safety border line. So I must choose B06 or ASA35. Iam from Europe so B06 is for me most avalible. If You are not able calculate it, You can use following pictures. It looks for me also usefull.


and

Next point is the maintenance. Chain shoul be time to time greased and in case of any mechanical damage should be replaced. Based on Czech or Slovak standard should be replaced after 2% of extension ,according EU standard it is after 3% extension. I mean this is very important unfortenatly I never saw this on any Youtube builds where guis are using chain from Alixpres without any strength tension value introduced by seller. I would say ,it can be little risky.
Idea of closed chain gear it looks nice, maybe I will design it, but definitly with 06B chain. I do not want to see ,what can happen inside gearbox in case that chain will be broken and block wheel:(

Thank You All for reading this comment and please let us to know if this theory was tested by You.

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Can I achieve the same result if it’s the other way around?
I mean my motor sprocket is 14t even and 65t odd for the wheel.
My other board have 12t by 47t.
All 25h systems using using motorcycle timing chains.

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It is general rules, to be honest I have nothing to compare how big influence have this rules on lifecycle, Mainly is inportant to avoid thath both sprocket will have even number of tooths or both will have odd number of tooths. But also it exist combination which will works also with it. Anvay according attached link on calculator, Your nombers will worrk great. Iam not sure what is your axial distance, but it should be ok. As Iam wrote this is theory from industry.

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Sorry. This is correct. Iam used different chain typ for first calculation. It have just dimensional ipact :slight_smile:

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FRC robotics forums love it, wish they had updated earlier maybe I would have used it more.

Could you show off some previous robotics work? not enough shown on this forum.
Introduce Yourself and Share Your Plans (SERIOUS)
^^ in this thread

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i have used 04b, 05b and 06b chain on emtbs. 04b too weak/ small for emtbs but on a small longboard works great. 05b is lightweight should only be used for low power jumper boards and 06b is double the strength of 05b imo the perfect chain for power to size ratio for mtbs, have a look at chain wax it works a treat for protecting chain from dirt ingress (when ya chain gets crispy)

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Thank You for Your experiences.

Gentleman’s

Did You try go-kart chain? It looks like alternative with small pitch and high strength. I suppose that availability of sprockets for us will be an issue.

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Sprockets can be machined easily enough.

How do the specs of go-cart chain compare against 06b?

I think the main problem with 06b chains (for MTB) is the diameter of the wheel sprocket and the lack of ground clearance. If you can make an improvement there without sacrificing robustness, only then would an enclosure become really practical.

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Let see: ČZ Řetězy s.r.o. - Kart chains
Pitch is less then 06B and strengts is very similiar. So it can solve clearence issue. Just this chain is not roller chain but bush. That mean need to be often changed and maintanned becouse chain is not rolling on sprocket, but sliding, probably noice will be also different. Noice and colour of sound will be probably different. Sure, sprocket can be mashined, just it is not so comon tooth profile, so Iam not sure if anybody is able to produce it. Anyway I will made both variant B06 and 219 drawings to check price.

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Because sprockets are widely used in industry, it is usually easy to obtain the CAD drawings for whatever chain type you want.
for example :

And their shape and flatness are good matches for laser or waterjet cutting, which is quite affordable and easy to get done locally. Typically much cheaper than CNC

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That is clear. I was talking about 219 chain and needed dimensions. Did You already tested 219 chain?

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McMaster-Carr Has anyone tried to use this ?

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Iam little afraid to covering chain. If You would like to use it, You must be clear that You will check extension of chain. So You will change chain befor will be break and block gears in cover.

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Just remark. Custom sprocket for cart chain 219 type if fckn expensive:( I made drawings and received few offers. Price was include motor mount on gear drive level :man_facepalming:

Would you mind sharing those drawings here? I’m really surprised to hear they were so expensive to manufacture. I wonder if the likes of @SabreDynamics, @moon or @Savage1 could advise on whether you’re being ripped off or if your design could be optimised for manufacturing cost.

Sure, design can be tuned to be cheaper, like remove of chamfer on pinion etc. I have price from local suppliers. I already asked on Alibaba some asian companies but Iwas not able find somebody with good reputation willing do so small series. Effort which i must invest to this activity is not equal to situation , that You can buy 06B or other most used chain sprocket common avalible on market.
Bellow pictures from 3D printed prototypes. In case that I will be an owner of cnc machine , maybe it will make a sense:)

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I bet the expensive part here is in the motor pinion, not in the sprocket. Sprockets can be laser or water jet cut out of the right thickness material and then you have to sand the edges a bit on an angle to make the teeth more chain friendly. That’s a 5mn job. I’d expect the sprocket to be around $10-30 each in small batches.

Pinion is more complex to produce, and I’d expect that to be quite expensive indeed, but it should be available already as is from AliExpress or similar. Or is that a crazily exotic chain type that no one in the world uses? Or do you have exotic requirements in terms of bore that make the available ones not compatible at all?

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Appropos of nothing I have had this link in my list forever.

I have to admit I’m kind of turned on by the idea of a dual-chain sprocket :slight_smile:

image

I CNC’d my sprockets out of Delrin, they work great.

Originally I started with a steel drive sprocket and wore it out way too quickly. Once I switched to Delrin, a couple of years on - I’m almost due for a new set. If I had dual Delrin I bet it would go forever.

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