I am hoping to conceal control rods on an RC airplane. Looking for a timing Hub with a 2~3 MM bore and outside diameter no more than 3/8inch . would like to join that to a larger diameter hub but have no clue of the tooth count from hub to nub or belt. catalog is overwhelming and not all hubs give all measurements. Do not have access to a walk in store to look at all options. Any help would be great
Hello @rich126 and welcome to the RobotShop community,
Maybe this one could work for you?
- Bore 3 mm
- Pitch Diameter: 8.59 mm / 0.338 inch
If not, you can find most of the options available here, if you are interested in one but the description doesn’t mention some of the specifications you are looking for let me know.
Thanks very much!, that is exactly what i am looking for. Another dumb question should do it, I assume that if the timing pulley is 9T , then the other pulley and belt need to also be 9T
Great!
I assume that if the timing pulley is 9T, then the other pulley and belt need to also be 9T
Not really, you need a 3mm pitch belt (4mm wide or less). And to choose the other pulley you could use this tool:
Thanks again for your reply! So if I understand, pitch size is the diameter of the pulley including the “catch ridge not actual tooth diameter”. tooth count is only based on how many teeth can be on that diameter pulley . With that said , in the example if i stay with finger tech every pulley tooth gap (distance between teeth} will be the same ,thus tooth count will change based on pitch diameter allowing more teeth but tooth gap remains the same and tooth count for belt is based on length. If that is true do all manufactures maintain “tooth gap distance” thus allowing you to mix and match brands ?? Sorry for my ignorance!
pitch size is the diameter of the pulley including the “catch ridge not actual tooth diameter”
No, pitch size is the “tooth gap distance”. The pulleys and belt should have the same pitch size to be compatible.
tooth count is only based on how many teeth can be on that diameter pulley
Yes, that’s correct
With that said , in the example if i stay with finger tech every pulley tooth gap (distance between teeth} will be the same ,thus tooth count will change based on pitch diameter allowing more teeth but tooth gap remains the same and tooth count for belt is based on length.
Not 100% sure I understood what you meant but I think you have the right idea you just misinterpreted what pitch size means.
Do all manufactures maintain “tooth gap distance” thus allowing you to mix and match brands ??
Not really, manufacturers usually offer multiple models with different “tooth gap distance”=pitch size.
For example, here’s a finger tech belt with 3mm pitch
And here’s an Actobotics belt with 5mm pitch:
In order to mix and match simply check if the pitch size matches and the belt width will work with the pulley you chose.
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By Geroge I think I got IT. Thanks for your patience!
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