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    Default reduce frequency, not torque

    Posting this as a separate thread, since this is a separate topic. I am interested in reducing vibrations from my 8" buffer. I added a speed controller to it's AC input, however the speed controller also reduces the torque of the buffer, I am guessing a current limiting device... I am interested in increasing torque while reducing RPM. Main goal is to reduce vibrations from 8" wheels, which correlates to RPM. I there a device that can do this for me? I would guess that I need a frequency converter, rather than current limiter, Any one can suggest something available off the shelf? May be even a gear reduction box?

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    Quote Originally Posted by pcm81 View Post
    Posting this as a separate thread, since this is a separate topic. I am interested in reducing vibrations from my 8" buffer. I added a speed controller to it's AC input, however the speed controller also reduces the torque of the buffer, I am guessing a current limiting device... I am interested in increasing torque while reducing RPM. Main goal is to reduce vibrations from 8" wheels, which correlates to RPM. I there a device that can do this for me? I would guess that I need a frequency converter, rather than current limiter, Any one can suggest something available off the shelf? May be even a gear reduction box?
    Not sure what you HAVE as a "speed controller", but a GOOD VFD would be the minimum.

    Even then, you might have to up the motor HP & Torque a size. Or even two if you need a drastic RPM drop.

    Why not seek to balance the buffer, first? Or replace it. 8" doesn't sound all that "industrial" to begin with and I do NOT even wanna know if it is from Harbor Freight...


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    Not from HF, but it is a crappy one i got to learn what i want from the real deal later. I have another thread for balancing the wheels, figured leave this thread for electrical side of things.My speed controller is the: "MLCS 9400 Standard Duty Router Speed Control". Looks like it is the current/voltage limiter, rather than frequency modifier.

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    Quote Originally Posted by pcm81 View Post
    Not from HF, but it is a crappy one i got to learn what i want from the real deal later. I have another thread for balancing the wheels, figured leave this thread for electrical side of things.My speed controller is the: "MLCS 9400 Standard Duty Router Speed Control". Looks like it is the current/voltage limiter, rather than frequency modifier.
    "Erg limiter" might be more accurate. Duty-cycles an ignorant SCR's ON time is all. No load-regulation to it.

    Goods news is you have ONLY hobby-grade junk, so no fear when you trash the lot of it for better gear.


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    Quote Originally Posted by Monarchist View Post
    "Erg limiter" might be more accurate. Duty-cycles an ignorant SCR's ON time is all. No load-regulation to it.

    Goods news is you have ONLY hobby-grade junk, so no fear when you trash the lot of it for better gear.

    Yup, So far getting hobby grade junk to play with, learn and figure out what I want from the real deal.I balanced the shafts using a scraper and a 50uin indicator, But still have imbalance with 8" buffs on. Trying to figure out how to slow it down without loosing torque.

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    Quote Originally Posted by pcm81 View Post
    ..how to slow it down without loosing torque.
    Type "T" Dee Cee motor has been the go-to since forever-ago. Hoists, elevators, electric rail, machine-tools, conveyor lines, etc.

    A nice 5 HP Reliance, brand new, is only about 12 thousand USD, too!



    All you REALLY need is common AC and a better motor, bearings, hubs, and buffs than what you have now.

    Off-the shelf Baldor @ 1-P 240 VAC was all we needed for long hours of production use.

    If you want "slower" without the economic pain or torque loss, just buy a decent 10" machine and run a good grade of 8" or even 6" buffs on it instead-of / as-well-as 10" ers.

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    Quote Originally Posted by Monarchist View Post
    Type "T" Dee Cee motor has been the go-to since forever-ago. Hoists, elevators, electric rail, machine-tools, conveyor lines, etc.

    A nice 5 HP Reliance, brand new, is only about 12 thousand USD, too!



    All you REALLY need is common AC and a better motor, bearings, hubs, and buffs than what you have now.

    Off-the shelf Baldor @ 1-P 240 VAC was all we needed for long hours of production use.

    If you want "slower" without the economic pain or torque loss, just buy a decent 10" machine and run a good grade of 8" or even 6" buffs on it instead-of / as-well-as 10" ers.
    Thanks for the advice, but i am afraid my 110 AC hook up won't pull the 5HP Reliance.
    On a more serious note, looks like i'll be adding a 3/4hp baldor to my shopping list. The $60 that my current buffer ran me was worth the things i learned from it so far.

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    Quote Originally Posted by Monarchist View Post
    Type "T" Dee Cee motor has been the go-to since forever-ago. Hoists, elevators, electric rail, machine-tools, conveyor lines, etc.

    A nice 5 HP Reliance, brand new, is only about 12 thousand USD, too!



    All you REALLY need is common AC and a better motor, bearings, hubs, and buffs than what you have now.

    Off-the shelf Baldor @ 1-P 240 VAC was all we needed for long hours of production use.

    If you want "slower" without the economic pain or torque loss, just buy a decent 10" machine and run a good grade of 8" or even 6" buffs on it instead-of / as-well-as 10" ers.
    Yep, Monarchist is correct with what you have your out of luck and going about your end goal vibration wrong. Your lower grade buffers motor is not balanced well. Balancing your wheels likely be of little help.
    No matter how slow you get it turning it will still be out of balance as you know. Regardless there is no way to slow that single phase motor down and not lose torque. Using what your using will ruin the motor in short time. I am 90% sure those router speed controllers are not made for that type of motor. I have been through a number of buffers over the years and the only one I can recommend is a Blador 3/4hp or larger. The Jets and Grizzly are all made in the same place and are not any good. You need to figure out what rpm your wheels and compound want or need to work efficiently. I my self like an 1800 rpm buffer for anything but the heaviest compounds. There is an art to buffing. Back when I was doing Lots of mirrors polished knives I used 3 buffers 1 3600 rpm 2 1800 rpm with those I had 5 different wheels and compound. From a 600 belt finished blade to mirror polished in 5 min or less.

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    Quote Originally Posted by B-Mathews View Post
    Yep, Monarchist is correct with what you have your out of luck and going about your end goal vibration wrong. Your lower grade buffers motor is not balanced well. Balancing your wheels likely be of little help.
    No matter how slow you get it turning it will still be out of balance as you know. Regardless there is no way to slow that single phase motor down and not lose torque. Using what your using will ruin the motor in short time. I am 90% sure those router speed controllers are not made for that type of motor. I have been through a number of buffers over the years and the only one I can recommend is a Blador 3/4hp or larger. The Jets and Grizzly are all made in the same place and are not any good. You need to figure out what rpm your wheels and compound want or need to work efficiently. I my self like an 1800 rpm buffer for anything but the heaviest compounds. There is an art to buffing. Back when I was doing Lots of mirrors polished knives I used 3 buffers 1 3600 rpm 2 1800 rpm with those I had 5 different wheels and compound. From a 600 belt finished blade to mirror polished in 5 min or less.
    Thank you for sharing your experience. I realized that the limit of what can be expected from this cheap buffer will be hit pretty soon, I now have a 3/4HP baldor on my wish list. What got me trying to balance and slow down the wheels is that the buffer runs smooth with bare shafts, but i guess the bearings with no load on them are the reason, cheap buffer, cheap bearings, get running ugly mighty fast with any load added to them.

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    Before accusing the motor of poor balance it's worth while checking it. Remove the buffing wheels and run it up. If the vibration is still there it's the motor or spigots. if not, it's the wheels. You can try dressing the wheels with a wood turning tool hald against a tool rest. If you're really enthusiastic, search for things such as 'automatic ball balancer' for ways to make a balancer that will dynamically reduce the out of balance of the machine.

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    Since all of you "bad people" have convinced me to eventually spend more money, here is something for yall's to drool over: Best Pedestal Buffer - Busch Buffer and Baldor Buffer - YouTube

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    Quote Originally Posted by pcm81 View Post
    Posting this as a separate thread, since this is a separate topic. I am interested in reducing vibrations from my 8" buffer. I added a speed controller to it's AC input, however the speed controller also reduces the torque of the buffer, I am guessing a current limiting device... I am interested in increasing torque while reducing RPM. Main goal is to reduce vibrations from 8" wheels, which correlates to RPM. I there a device that can do this for me? I would guess that I need a frequency converter, rather than current limiter, Any one can suggest something available off the shelf? May be even a gear reduction box?
    You're looking at this wrong, not to mention overthinking it. If you want good results buffing you need the right surface speed. You manage this with mop diameter. Slowing the motor with the right size mop gives you too slow surface speed. You want to go slower, use a smaller (6" or 4") mop. Same result (less surface speed, less vibration) without losing torque.

    How well is this thing bolted down?

    Sent from my HTC 10 using Tapatalk

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    Quote Originally Posted by pcm81 View Post
    Since all of you "bad people" have convinced me to eventually spend more money, here is something for yall's to drool over: Best Pedestal Buffer - Busch Buffer and Baldor Buffer - YouTube
    That is a nice stand but I weld up my own as the height of the spindle is very important to me so I can have a firm grip and have my arms looked into my sides. The buffer is the most dangers tool in a knife makers shop by far.

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    Quote Originally Posted by B-Mathews View Post
    That is a nice stand but I weld up my own as the height of the spindle is very important to me so I can have a firm grip and have my arms looked into my sides. The buffer is the most dangers tool in a knife makers shop by far.
    I take the opposite approach and don't press the work piece against the buffer hard enough that it would rip it out. Even in knife sharpening, light pressure is the key. If you have to press the piece hard to remove the metal that you have to remove, that means the piece is not yet ready for that grit. But of-course my way is not "the only right way". There are plenty of successful techniques that require firm grip and heavy hand on the wheel.


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