Author Topic: V Belt Questions  (Read 2513 times)

18hvenhuizen

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V Belt Questions
« on: September 29, 2016, 09:34:48 am »
I am building a drum spinner and am trying to figure out how to drive it. So far I have some up with needle bearings inside the drum spinning on a dead shaft. There will be a pulley mounted on the drum. I need a 4:1 gear ratio (preferably 4 inch and 1 inch pulleys). What I want to know is a.) Do v belt pulleys reduce by number of teeth on the pulley or by size? b.) Where can I get the right pulleys? (couldn't find the right sizes in McMaster-Carr, if anyone else can thank you!) c.) Can I weld the pulleys to the drum?
This drum spinner will be about 20 lbs and used on a 120 lb. bot. I am using an Ampflow A28-150 to drive it. I don't want to spend too much on these belts and pulleys.

Coboxite

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Re: V Belt Questions
« Reply #1 on: September 29, 2016, 01:21:05 pm »
V belt reduction is based off of pulley size, not teeth(That would be timing belts.) Some V belts have teeth, but they're for heat dispersion.


Most commercial pulleys are made to be cheap. You're probably going to have to machine the pulleys yourself.


You can weld the pulley on, as long as you're precise about it. Even a few millimeters off will cause the whole thing to shake violently.


You should really not go cheap on your transmission meathod. Next to your weapon shaft, its the most important part. Go cheap at your own peril.

18hvenhuizen

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Re: V Belt Questions
« Reply #2 on: September 30, 2016, 10:49:13 pm »
V belt reduction is based off of pulley size, not teeth(That would be timing belts.) Some V belts have teeth, but they're for heat dispersion.


Most commercial pulleys are made to be cheap. You're probably going to have to machine the pulleys yourself.


You can weld the pulley on, as long as you're precise about it. Even a few millimeters off will cause the whole thing to shake violently.


You should really not go cheap on your transmission meathod. Next to your weapon shaft, its the most important part. Go cheap at your own peril.

We don't have anything we can machine pulleys with, and we can't fit it into our budget. What shaft pulleys would you recommend buying?

Coboxite

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Re: V Belt Questions
« Reply #3 on: October 01, 2016, 12:42:22 am »
If you can't machine a pulley yourself, outsource it to somebody else. If you really need to buy the pulley, I found one that might fit your design, but I'd be cautious. Its not meant for combat, and very likely could be made from inferior steel.


Though, I do wonder how you can afford to machine the drum and not the pulley.
« Last Edit: October 01, 2016, 02:15:10 pm by Coboxite »

Team whanton2

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Re: V Belt Questions
« Reply #4 on: October 01, 2016, 01:08:14 am »

18hvenhuizen

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Re: V Belt Questions
« Reply #5 on: October 03, 2016, 09:15:19 am »
If you can't machine a pulley yourself, outsource it to somebody else. If you really need to buy the pulley, I found one that might fit your design, but I'd be cautious. Its not meant for combat, and very likely could be made from inferior steel.


Though, I do wonder how you can afford to machine the drum and not the pulley.

We're not machining a pulley. We have a large piece of pipe, sheet metal, and a bar of steel that we are using to build it. We're using lots of welding.

18hvenhuizen

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Re: V Belt Questions
« Reply #6 on: October 03, 2016, 09:20:26 am »
If you can't machine a pulley yourself, outsource it to somebody else. If you really need to buy the pulley, I found one that might fit your design, but I'd be cautious. Its not meant for combat, and very likely could be made from inferior steel.


Though, I do wonder how you can afford to machine the drum and not the pulley.

We're not machining a pulley. We have a large piece of pipe, sheet metal, and a bar of steel that we are using to build it. We're using lots of welding.
Sorry I meant were not machining a *drum*

Jeff Gier

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Re: V Belt Questions
« Reply #7 on: October 03, 2016, 05:18:32 pm »
I've seen V-belts and pulleys at ace hardware before.  They are steel, so you should be able to weld them to it.