I’v been an HVAC mechanic for 29 years and have worked on fan, sheaves and pulleys of all kinds an sizes. I’v worked blower sections as large as a full story of a 40 floor building. I’v worked with mechanical engineers of all levels. My compliments to you my friend you are a great teacher!
This is totally the opposite of reality. The chart shows how much horse power can be transmitted using a larger diameter pulley due to the ability to grip the belt. Your leverage idea works exactly the opposite of how you explained it. The further from the center of rotation the pressure applied will be less, that is true, but when the distance from the center to the point of resistance is greater, the power that is required to create rotation is greater. Think of it this way. If you had a wrench attached to a shaft, as you illustrated, and you had a certain amount of torque applied to the shaft, would it be easier to prevent rotation by placing your hand on the wrench 4" from shaft center or 18" from center. Obviously 18". This, therefore, means it would require much greater HP to rotate a 36" diameter pulley than an 8" pulley.
You earned my subscription. Every video I have watched from you has kept me listening til the end. Thank you, and please continue making educational videos! The world needs you on TH-cam! Lol
Thank you Jeremy. I checked this channel out looking for inspiration. My new ride-on lawnmower was chewing through blade drive belts, which fail to turn the blade, and then overheat by friction and break. The tensioning pulley is inside the belt track and moves outwards to tighten the belt, and in so doing it reduces the lap angle on the driven pulley to 125 degrees. I was stuck on the idea that this was the principal problem. Surprisingly I had Shigleys on my bookshelf but I found no clear indication of minimum lap angle. The realization of the real fault dawned on me after quite some time. As is so often the case, the answer lay not in the highly technical but in the basics. The fact was that the original belts were too long, and while the belt tension appeared to be adequate, in fact the tensioning pulley was at the end of its spring arm travel, and a little warming of the belt was enough to expand a little and allow slip to start. Soon the belt would roast and shred. I fitted a belt just one inch shorter. It increased the tension and the lap angle by 12 degrees. I got my lawn mowed.
I had the same issue. I added a piece of chain from the tensioner arm so I can adapt to different length belts. I went from using 2-3 belts a year to 1 belt lasting 2-3 years.
Been vaguely planning out a custom made table saw build to replace my bodged together upside down circular saw setup and this kind of information is absolutely priceless. Thanks for sharing what you've learned and helping all of us better tinkerers and makers.
Minor technical inaccuracy at 5:40: Work = Force x Distance moved. Compared to the shorter wrench, you are using less FORCE with the long wrench, but by moving the handle a greater distance you are doing the same amount of WORK. You are my favorite TH-camr. Keep up the good work (no pun intended)!
Just learned about pulleys in a class i took this semester. We used the same book! Incredible that you condensed the basic concepts down to 6 minutes. Good work!
Thanks Jeremy. I am building a Trommel to separate rocks from dirt using a 55 gallon drum cut for screens and driven by a motor and pulleys. This video is very helpful.
Clarification. The key point for tip # 7 is The belt is experiencing more force as the pulley gets smaller. I show the formula in the video. The only conclusion you should get from that is small pulleys might reduce the life of your belt. It has no effect on hp. (Edited to be more concise.)
Still a little confused you're not really gaining power you're just not loosing as much as you would with a small pulley. The large pulley has a better and easier contact area and just works better. Leverage wise it's still just a gear ratio isn't it? You can gain torque or rpm, horsepower is what ever the motor can supply. I'm just a plumber but I live in my garage and enjoy your work so keep it up. You make things easier to understand my mechanic skills and wood working are decent but your engineering and electrical are fun to watch. Oh and last question what are the little hearts after the comments? Also a little computer illiterate.
Forget about every other part of the system... we are only interested in the force on the belt. For the same torque you either have a lot of force and a small lever or a little force and a large lever. If the BELT has a small lever as when it goes around a small pulley, it will have to endure more force through it. Therefore the tension stresses in the belt are highest when wrapped around a small pulley...this changes when the belt goes around to the other pulley. Thinking of one small section traveling around. You can do the math using the formula shown in the video. Like I said in the video, It is counterintuitive when you are thinking about all the components. Focus on the belt
I think I understand a little bit better it's the first chart that screwing me up. I believe the chart is explaining how much horse power can be pushed through a particular size sheave at a given rpm. Because as you said the smaller the sheave the less contact area you have. You can't put 8hp to a 2 5/8" sheave unless you tighten the crap out of it which is all bad. Thanks for the reply and awesome as usual video. But what are the little hearts for after peoples comments? P.S Merry Christmas to you and your family
That is TH-cam’s way of letting you know I love a comment. I use that instead of the thumbs up so people know I read and acknowledged their comment. If I use the thumb you don’t know who put it there.
This video is fantastic! Been struggling with a large centrifugal blower at work burning up belts and pulleys over the last three years. New bearings, soft starter, laser alignment- Still smoking belts and pulleys way more often then it should. I watched this and started to question whether the pulley diameters were large enough to effectively drive this load? Sized a new set 1.5x larger that would maintain close to the same RPM yet increase the leverage and wrap and installed. My RPMS went from 1445 to 1464 but my running amps dropped from 31A to 22A. Interesting! Also absolutely no belt slip at this point. Going to recheck belt tension in the morning but happy with the results so far! Thank you
Hey Jeremy, I have been watching your videos for a bit now and I gotta thank you. I was addicted to taking things apart ever since I was little. I took apart the tv...the new tv... it was not appreciated. You, among a few others have helped me understand what to do with the bits’n’pieces after the deconstruction of a particular thingy. So, thanks again for letting me into your shop for a laugh partner. I hope this finds you doing well.
This is excellent. I just built a thickness sander using some of the information from your chanel. Thanks for putting this together it is a great resource
Keep in mind that increasing the diameter of a motor drive pulley can and will increase the amp draw of the motor. It can also change the cfm of a blower(s) attached to the driven pulley shaft which can be critical in air conditioning applications.
Mr. Fielding, I subscribed because I love the information about the components that make up the thing you are making. Not many people take the time to explain how all of these things work. Thank you for your teachings! I look forward to learning more! Thank you! Thank you! Thank you!
Thank you..twenty years I have been having issues with my boat lift pulleys and belts..the pulleys have been scalloping and causing the belts to slip and burn up.. They too used a very large pulley on the bracket of the lift but a super small pulley on the motor side (the one that always scalloped causing the slip and the belt to burn) this video is late. But again I was having issues and figured I'd TH-cam it to see if anyone else was having the same issues. So glad you did this video.. I was afraid of going to a bigger pulley etc..now with the information you provided perfectly, I understand the issue and can correct it this time!! Thank you very much!! Much appreciate this tutorial!!
I just found your channel last night. I really enjoy the way you explain things and use what you can salvage to build with. I'm an electrical engineering student and avid garage tinkerer of salvaged things. Thank you!
Thank you, Mr. Fielding. I did find this helpful. I never knew that there were so many factors for belts. As well, this explained a mystery I have in my home. That being, why my whole-house fan uses such a skinny belt. The answer was in the first example, wrap.
Thanks for this. My belt was squeaking on my new car build. Turns out the mechanic used an A belt, when the 400hp/tq engine needs at least a 1.5" belt per your book. I've ordered a new pulley/belt set.
I really like your videos!! I used to have access to all sizes of motors I changed out, some weren't even damaged or just needed bearings and I gave them away to people I knew in motor rewinding field. I wish I had some of those motors now since watching your videos. Some of the motors were so big it took 2 men to unload but most were 1 to 4 hp. I'm gonna keep my eyes out for some I can strip out of old equipment. Thanks again for your videos
Jeremy, I usually gain something (some I learn a lot) from your videos. Thanks again for saving me lots of extra work when I go to set up more of my own projects.
Also I have I built this a trike with a 6 horsepower Honda motor I have a very short belt with a smaller one on top and larger drive belt to the axle directly underneath the small belt still is a very short belt I don't have much wrap what is the solution for this my axle is directly beneath my motor output shaft very small belt as in length police almost touching each other one above the other what can I do to gain traction on this on this belt so that it will actually turn my trikes rear axle instead of slept
Yeah I have a centrifugal clutch run trike driving a 6-inch police probably a 4 inch pulley I cannot keep I don't have much wrap Beltre are police are almost touching each other one above the other how do I alleviate this slipping
I think I will try and put some blocks underneath the motor to make the belt tension tighter but what side of the I'll be drive belt what I put the tensioner if they both turned counter-clockwise the motor shaft and the rear axle
So what I put the tensioner on the front of the drive belt or the rear I would put out word tension on the belt from the end pushing out but that would leave even more blessed up contact that would leave even less rap on the drive pulley output shaft of the engine
A lot of good points mentioned in this video. I am working on modifying a 5-speed dual-pulley V-belt driven drill press to be able to drill 12 mm diameter holes through a 7 mm thick 62+ Rockwell C bearing steel thrust washer. This is no easy task. My M42 cobalt drill bits just left a small dent when bearing down with well over 500 lbs on the spindle. No cutting action. That washer is so hard, nothing short of tungsten carbide will scratch it. This operation calls for a starting spindle speed of around 200 rpm. The lowest spindle speed of my drill press is 740 rpm, from a motor speed of 1790 rpm. To achieve a 9:1 speed ratio with V-belts, you have to use an intermediate reducer pulley, otherwise the motor pulley would slip way too easily from insufficient wrap. The importance of wrap angle cannot be overstated. For a given amount of belt tension, the amount of torque than can be transferred without slipping is directly proportional to pulley diameter, and exponentially correlated with the wrap angle! As the speed ratio of the belt drive tends further from unity, the amount of torque that can can be transferred decreases for the smaller pulley. This places a practical limit on the effective "gear" ratio of the belt drive. Increasing the center-to-center distance of the pulleys increases the wrap angle and torque transmission capability of the drive, but I'm fairly limited in this regard with the drill press because of the belt drive housing space constraints. An intermediate pulley will allow me to break down the 9:1 ratio I need into two much more feasible 3:1 ratios. Only, the intermediate pulley needs to be movable so that it can be tensioned. For this, I plan to to install it in a flange block bearing mounted into T-track.
In a pinch, I recommend using a hand drill (with variable speed) to drive your drill press at a low RPM. You will have to improvise the connection (on my Jet drill press, a 30mm socket fits on the motor pulley nicely, and a 1/4 hex to 1/2 square drive adapter makes it easy to drive with the hand drill). I've used this setup (+cutting oil) for drilling and tapping hard materials. I realize your comment was a couple years old but hopefully you or someone else finds this shortcut helpful!
Nice! I got an old scroll saw from my neighbor and I’ve been messing around with different pulley sizes. The way I set mine up, similar to a lot of belt driven contractor style table saws, the weight of the motor puts the tension on the belt. And it works ok until it starts vibrating. I’m going to experiment with springs and other mechanisms to prevent the motor from jumping.
So glad I watched this! I am building an apple scratter and have salvaged a motor from a tumble dryer. I searched on youtube for "Can I use a dimmer to slow down rpm on an electric motor" and I found your video on this which has led me to this goldmine of information and motivation. I subscribed and am finding the whole thing fascinating, I am 60 and loving all this new information. Thank you.
The last part about the belt rating per pully size had me thinking for a while. I understand it now but it wasn't something I'd considered before...thanks!
Quite clearly Jeremy knowledge is way above average and explaining it on video even better. Any motor pulley under 75mm is a pain , worth spending a few bucks more and get a cogged belt for those small diameter ones.
interesting, although when replacing pulleys on flywheels for stamping presses, it is implied that the tension is tight apparent to a fixed dimension, then after a calculated amount of working hours, the belt is re-tensioned. i also think alignment is a very important factor that deserves to be mentioned, as a maintenance engineer, i have found most cases of machine failure with pulleys, is poor pulley alignment. cool video and nice bandsaw, shoutout from New Zealand
You and your videos are great too watch and to learn from however those little things might be. Keep at it, and I too wish you and family a very good festive time.
Thank You again Mr. Fielding. And also for sighting your source book. Very good explanation. And to check alignment , I always carried a straight edge; a piece of string. And a very happy and safe New Year to you and yours sir.
Really love these purely educational videos! I’m working a lot with gt2 timing belts right now for the robot arm I’m building and I’d love to watch a video about timing belts with timing pulleys!
Oh, BTW that homebuilt bandsaw is awesome. I came to this site because I have a contrary rototiller and I thought it might be the design and belt wrap. After watching this I have figured it out!
Thank You for this video! I am putting together an antique lathe with no motor pully that has a four groove pully on the lathe. I was about to make a big mistake in purchasing a multi-groove pully for the motor. Definitely became a subscriber! Thank You Again!
You will still need a four groove pully for the motor. The motor pully will be installed in the opposite direction of the drive pully using only one belt. That is how you change the speed of the lathe rotation! I suggest that you look at a drill press belt system. Same idea, small motor pully to larger lathe pully gives less speed than the larger motor pully to the smaller lathe pully. It appears that you will have four speeds to choose from, depending on the material being worked. Just move the belt to the desired speed.
I find the best way to visualise the pulley ratios is to think of a bicycle. The fastest speed is a big chain ring with a small rear cog. For hill climbs a small front cog and a big rear cog does the trick. Great video thanks!
I first learned about belts and pulleys when I was modifying riding lawn mowers to go really fast. I really wish I would have seen this then it would have saved me a lot of frustration.
If you are stuck having to use an undersized pulley, a notched V-belt is some help in easing the wrapping problem and/or over tightening the belt. Another important consideration in getting good belt performance is to ensure the pulley shafts are parallel and the sheaves are aligned with each other. If you have belt problems that's the first thing to check.. even on a brand new piece of equipment. Merry Christmas!
I have an emergency supply fan with a motor with double adjustable sheaves. One of the sheaves is more open than the other. Problem I have is that when you create tension on the pulleys, one of the belts is tight and the other really loose. In order for the second belt to have some tension, the first one becomes suuuuper tight. This seems to be creating opposing tension on the belts, or tension on opposite sides of the belts (like you mention at around 2:26) , causing the motor to work harder and not blow the air it is intended to. So, my question is: would changing the belt size for one of the sheaves to create even tension help solve this issue? The fan runs only on emergencies only (thankfully we have not had any) and we had not noticed the potential problem with this setup. If I remove one of the belts and create the necessary tension on the one belt, the motor turns perfectly fine. I appreciate your feedback!
All you said was very correct and interesting but could I add there are other types of "V" belts and one in particular designed to be used with smaller pulleys. The clogged V belt is such a type especially the SPZ range will work satisfactory with pulleys down to two inches with a one horse power motor, especially useful on mini Lathes.
It's a great video. Here is a real world belt challenge: A garden tractor with a front mounted vertical shaft engine needs to power a rear mounted garden tiller. The V belt required is 70 inches long because it not only goes to the rear of the tractor, it also has to change direction over idler pulleys and a tensioner to drive a horizontally mounted pulley on the tiller reduction box. The problem is that the belt is so long under the tractor that it stretches and flexes and pops off under load. You cant have anything that hangs to low under the tractor and you can't overly tension the belt because of the electric clutch. How do you support the belt so it doesn't come off. This is pretty typical of older equipment.
Ive got a racing lawnmower and i wonder why im always eating belts! I used to have a 6 inch pulley on the engine and a 2 inch on the transaxle, i would go through belts like crazy. Now i have a 10 inch on the front and a 3 1/2 on the transaxle. Ive had it like that for several months and only went through 1 belt, and the only reason it broke is because my rear pulley broke. It was only cast aluminum and didnt like the 10k plus rpms and the 20+ horsepower i was pushing through it :) im now thinking about doubling everything up to have more power delivery, i can tell the belt slips a bit because the pulleys get pretty hot. Ive definately learned a bunch!
6:19 Has anyone asked yet, why is the motor pulley at 6:19 offset from the key? Looks like the shaft key is at 11 o'clock but the pulley key way is at 1 o'clock.
Oops, Jeremy. The last motor your featured that was belted to the large wooden pulley, the key way on the motor shaft was not aligned with the key way on the pulley. Is there some alternative method of securing the pulley to the motor shaft?
Really good video! Your explanation, along with the demonstration, made it super easy to understand some of the issues faced when dealing with v-belts. Thanks for making this!
Hi Jeremy from Chile, how many hp is recommended in a motor to be able to easily cut 6-inch wood, because my 3/4 hp band saw stops a lot when cutting wood over 4 inches, thanks in advance.
Thanks again for another informative video. I have no comments. I would just like to wish you and yours a Merry Christmas and thank you for all your help this year.
I’v been an HVAC mechanic for 29 years and have worked on fan, sheaves and pulleys of all kinds an sizes. I’v worked blower sections as large as a full story of a 40 floor building. I’v worked with mechanical engineers of all levels. My compliments to you my friend you are a great teacher!
Hi fella can I contact you by email I would like to ask you a question on fan touque Dave
Are you in U.K. fella.
This is totally the opposite of reality. The chart shows how much horse power can be transmitted using a larger diameter pulley due to the ability to grip the belt. Your leverage idea works exactly the opposite of how you explained it. The further from the center of rotation the pressure applied will be less, that is true, but when the distance from the center to the point of resistance is greater, the power that is required to create rotation is greater. Think of it this way. If you had a wrench attached to a shaft, as you illustrated, and you had a certain amount of torque applied to the shaft, would it be easier to prevent rotation by placing your hand on the wrench 4" from shaft center or 18" from center. Obviously 18". This, therefore, means it would require much greater HP to rotate a 36" diameter pulley than an 8" pulley.
Fully alimented lenth full and v belt detan es tighted full loos baic motor ssmll setled dimetr hosepower tighted
You earned my subscription. Every video I have watched from you has kept me listening til the end. Thank you, and please continue making educational videos! The world needs you on TH-cam! Lol
I am honored thank you! Welcome to the neighborhood
Thank you Jeremy. I checked this channel out looking for inspiration. My new ride-on lawnmower was chewing through blade drive belts, which fail to turn the blade, and then overheat by friction and break. The tensioning pulley is inside the belt track and moves outwards to tighten the belt, and in so doing it reduces the lap angle on the driven pulley to 125 degrees. I was stuck on the idea that this was the principal problem. Surprisingly I had Shigleys on my bookshelf but I found no clear indication of minimum lap angle. The realization of the real fault dawned on me after quite some time. As is so often the case, the answer lay not in the highly technical but in the basics. The fact was that the original belts were too long, and while the belt tension appeared to be adequate, in fact the tensioning pulley was at the end of its spring arm travel, and a little warming of the belt was enough to expand a little and allow slip to start. Soon the belt would roast and shred. I fitted a belt just one inch shorter. It increased the tension and the lap angle by 12 degrees. I got my lawn mowed.
I had the same issue. I added a piece of chain from the tensioner arm so I can adapt to different length belts. I went from using 2-3 belts a year to 1 belt lasting 2-3 years.
Been vaguely planning out a custom made table saw build to replace my bodged together upside down circular saw setup and this kind of information is absolutely priceless. Thanks for sharing what you've learned and helping all of us better tinkerers and makers.
Minor technical inaccuracy at 5:40: Work = Force x Distance moved. Compared to the shorter wrench, you are using less FORCE with the long wrench, but by moving the handle a greater distance you are doing the same amount of WORK. You are my favorite TH-camr. Keep up the good work (no pun intended)!
Just learned about pulleys in a class i took this semester. We used the same book! Incredible that you condensed the basic concepts down to 6 minutes. Good work!
Fascinating. I wish all my teachers had been able to communicate as well as you do. Thanks.
Thanks Jeremy. I am building a Trommel to separate rocks from dirt using a 55 gallon drum cut for screens and driven by a motor and pulleys. This video is very helpful.
This helped me fix my bandsaw's belt issue, thanks!
Clarification. The key point for tip # 7 is The belt is experiencing more force as the pulley gets smaller. I show the formula in the video. The only conclusion you should get from that is small pulleys might reduce the life of your belt. It has no effect on hp. (Edited to be more concise.)
Still a little confused you're not really gaining power you're just not loosing as much as you would with a small pulley. The large pulley has a better and easier contact area and just works better. Leverage wise it's still just a gear ratio isn't it? You can gain torque or rpm, horsepower is what ever the motor can supply. I'm just a plumber but I live in my garage and enjoy your work so keep it up. You make things easier to understand my mechanic skills and wood working are decent but your engineering and electrical are fun to watch. Oh and last question what are the little hearts after the comments? Also a little computer illiterate.
Forget about every other part of the system... we are only interested in the force on the belt. For the same torque you either have a lot of force and a small lever or a little force and a large lever. If the BELT has a small lever as when it goes around a small pulley, it will have to endure more force through it. Therefore the tension stresses in the belt are highest when wrapped around a small pulley...this changes when the belt goes around to the other pulley. Thinking of one small section traveling around. You can do the math using the formula shown in the video. Like I said in the video, It is counterintuitive when you are thinking about all the components. Focus on the belt
I think I understand a little bit better it's the first chart that screwing me up. I believe the chart is explaining how much horse power can be pushed through a particular size sheave at a given rpm. Because as you said the smaller the sheave the less contact area you have. You can't put 8hp to a 2 5/8" sheave unless you tighten the crap out of it which is all bad. Thanks for the reply and awesome as usual video. But what are the little hearts for after peoples comments? P.S Merry Christmas to you and your family
That is TH-cam’s way of letting you know I love a comment. I use that instead of the thumbs up so people know I read and acknowledged their comment. If I use the thumb you don’t know who put it there.
OK a little embarrassed about the heart thing but my grandma would be happy as I learned something new today keep up the videos.
This video is fantastic! Been struggling with a large centrifugal blower at work burning up belts and pulleys over the last three years. New bearings, soft starter, laser alignment- Still smoking belts and pulleys way more often then it should. I watched this and started to question whether the pulley diameters were large enough to effectively drive this load? Sized a new set 1.5x larger that would maintain close to the same RPM yet increase the leverage and wrap and installed. My RPMS went from 1445 to 1464 but my running amps dropped from 31A to 22A. Interesting! Also absolutely no belt slip at this point. Going to recheck belt tension in the morning but happy with the results so far! Thank you
And what was the gearing ratio before and what's it now?
So all the power was being lost to friction from the higher tension and belt flexing with the smaller diameter pulleys I guess-
Hey Jeremy, I have been watching your videos for a bit now and I gotta thank you. I was addicted to taking things apart ever since I was little. I took apart the tv...the new tv... it was not appreciated. You, among a few others have helped me understand what to do with the bits’n’pieces after the deconstruction of a particular thingy. So, thanks again for letting me into your shop for a laugh partner. I hope this finds you doing well.
It does... thanks for sharing 👍
This is excellent. I just built a thickness sander using some of the information from your chanel. Thanks for putting this together it is a great resource
Keep in mind that increasing the diameter of a motor drive pulley can and will increase the amp draw of the motor. It can also change the cfm of a blower(s) attached to the driven pulley shaft which can be critical in air conditioning applications.
100% Right
Must check Amp Draw to the Spec Sheet Numbers.
Thank You
I instantly subscribed. I appreciate your thorough, easy to understand, explanations.
Mr. Fielding, I subscribed because I love the information about the components that make up the thing you are making. Not many people take the time to explain how all of these things work. Thank you for your teachings! I look forward to learning more! Thank you! Thank you! Thank you!
👍
Your complexion is at contest with your education. Bravo.
Thank you..twenty years I have been having issues with my boat lift pulleys and belts..the pulleys have been scalloping and causing the belts to slip and burn up.. They too used a very large pulley on the bracket of the lift but a super small pulley on the motor side (the one that always scalloped causing the slip and the belt to burn) this video is late. But again I was having issues and figured I'd TH-cam it to see if anyone else was having the same issues. So glad you did this video.. I was afraid of going to a bigger pulley etc..now with the information you provided perfectly, I understand the issue and can correct it this time!! Thank you very much!! Much appreciate this tutorial!!
I just found your channel last night. I really enjoy the way you explain things and use what you can salvage to build with. I'm an electrical engineering student and avid garage tinkerer of salvaged things. Thank you!
Thank you for taking the time to make this video. You explain the process very well.
Sir. You are an excellent teacher. Bravo.
Thank you, Mr. Fielding. I did find this helpful. I never knew that there were so many factors for belts. As well, this explained a mystery I have in my home. That being, why my whole-house fan uses such a skinny belt. The answer was in the first example, wrap.
I've been working on designing a few machines, this video sums up a lot of information I had to find very nicely!
Jeremy is clear and professional in his delivery! I learned a lot!
Thanks for this. My belt was squeaking on my new car build. Turns out the mechanic used an A belt, when the 400hp/tq engine needs at least a 1.5" belt per your book. I've ordered a new pulley/belt set.
This video was and is so helpful. The info on the power rating for the belt answered my question on why I need 2 belts on my compressor. Thanks!
this channel is a complete course for my project.
I really like your videos!! I used to have access to all sizes of motors I changed out, some weren't even damaged or just needed bearings and I gave them away to people I knew in motor rewinding field. I wish I had some of those motors now since watching your videos. Some of the motors were so big it took 2 men to unload but most were 1 to 4 hp. I'm gonna keep my eyes out for some I can strip out of old equipment. Thanks again for your videos
Thanks for the useful video. I'm going to install a reverse pulley on my rototilller and I'm in the learning phase. Thanks again.
This helped me choose the proper pulleys for my milling machine. Much appreciation for this video!
Jeremy, I usually gain something (some I learn a lot) from your videos. Thanks again for saving me lots of extra work when I go to set up more of my own projects.
Also I have I built this a trike with a 6 horsepower Honda motor I have a very short belt with a smaller one on top and larger drive belt to the axle directly underneath the small belt still is a very short belt I don't have much wrap what is the solution for this my axle is directly beneath my motor output shaft very small belt as in length police almost touching each other one above the other what can I do to gain traction on this on this belt so that it will actually turn my trikes rear axle instead of slept
Yeah I have a centrifugal clutch run trike driving a 6-inch police probably a 4 inch pulley I cannot keep I don't have much wrap Beltre are police are almost touching each other one above the other how do I alleviate this slipping
I suppose I could raise the motor to tension the belt
I think I will try and put some blocks underneath the motor to make the belt tension tighter but what side of the I'll be drive belt what I put the tensioner if they both turned counter-clockwise the motor shaft and the rear axle
So what I put the tensioner on the front of the drive belt or the rear I would put out word tension on the belt from the end pushing out but that would leave even more blessed up contact that would leave even less rap on the drive pulley output shaft of the engine
A lot of good points mentioned in this video. I am working on modifying a 5-speed dual-pulley V-belt driven drill press to be able to drill 12 mm diameter holes through a 7 mm thick 62+ Rockwell C bearing steel thrust washer. This is no easy task. My M42 cobalt drill bits just left a small dent when bearing down with well over 500 lbs on the spindle. No cutting action. That washer is so hard, nothing short of tungsten carbide will scratch it. This operation calls for a starting spindle speed of around 200 rpm. The lowest spindle speed of my drill press is 740 rpm, from a motor speed of 1790 rpm. To achieve a 9:1 speed ratio with V-belts, you have to use an intermediate reducer pulley, otherwise the motor pulley would slip way too easily from insufficient wrap. The importance of wrap angle cannot be overstated. For a given amount of belt tension, the amount of torque than can be transferred without slipping is directly proportional to pulley diameter, and exponentially correlated with the wrap angle! As the speed ratio of the belt drive tends further from unity, the amount of torque that can can be transferred decreases for the smaller pulley. This places a practical limit on the effective "gear" ratio of the belt drive. Increasing the center-to-center distance of the pulleys increases the wrap angle and torque transmission capability of the drive, but I'm fairly limited in this regard with the drill press because of the belt drive housing space constraints. An intermediate pulley will allow me to break down the 9:1 ratio I need into two much more feasible 3:1 ratios. Only, the intermediate pulley needs to be movable so that it can be tensioned. For this, I plan to to install it in a flange block bearing mounted into T-track.
In a pinch, I recommend using a hand drill (with variable speed) to drive your drill press at a low RPM. You will have to improvise the connection (on my Jet drill press, a 30mm socket fits on the motor pulley nicely, and a 1/4 hex to 1/2 square drive adapter makes it easy to drive with the hand drill). I've used this setup (+cutting oil) for drilling and tapping hard materials.
I realize your comment was a couple years old but hopefully you or someone else finds this shortcut helpful!
Your craftsmanship and ingenuity is undeniable. (HVAC-R trained and I work on freeze dryers lyophilizers)
Thank you!
Superb video. It solved my drill press belt slippage problems. Cheers from Spain.
Nice! I got an old scroll saw from my neighbor and I’ve been messing around with different pulley sizes. The way I set mine up, similar to a lot of belt driven contractor style table saws, the weight of the motor puts the tension on the belt. And it works ok until it starts vibrating. I’m going to experiment with springs and other mechanisms to prevent the motor from jumping.
That is the main problem with that design. The belt can move the motor.
So glad I watched this! I am building an apple scratter and have salvaged a motor from a tumble dryer. I searched on youtube for "Can I use a dimmer to slow down rpm on an electric motor" and I found your video on this which has led me to this goldmine of information and motivation. I subscribed and am finding the whole thing fascinating, I am 60 and loving all this new information. Thank you.
wonderful video, this is why youtube is so good, it provides those with a wish to learn the best teachers.
The last part about the belt rating per pully size had me thinking for a while. I understand it now but it wasn't something I'd considered before...thanks!
I added a note to the description which gives more detail on this.
Quite clearly Jeremy knowledge is way above average and explaining it on video even better. Any motor pulley under 75mm is a pain , worth spending a few bucks more and get a cogged belt for those small diameter ones.
interesting, although when replacing pulleys on flywheels for stamping presses, it is implied that the tension is tight apparent to a fixed dimension, then after a calculated amount of working hours, the belt is re-tensioned. i also think alignment is a very important factor that deserves to be mentioned, as a maintenance engineer, i have found most cases of machine failure with pulleys, is poor pulley alignment.
cool video and nice bandsaw, shoutout from New Zealand
I added a note to the description about alignment. Thanks for sharing!
Jeremy is the guy Matthias calls when he needs something explained.
LOL
Lol
Mark McCluney ??? When does that happen. ??!?
No offense to Jeremy. But no. Let’s not disrespect the god.
Who?
Very good video, I’ve never thought of it that way till now. You opened my eyes to understand better.
You and your videos are great too watch and to learn from however those little things might be. Keep at it, and I too wish you and family a very good festive time.
I'm a vibration analyst for commercial HVAC and this video was very helpful not only to me but to the fan builders I train
Great video, had many of the answers I needed to fix my design, thanks Jeremy. Great content?
Thank You again Mr. Fielding. And also for sighting your source book. Very good explanation. And to check alignment , I always carried a straight edge; a piece of string. And a very happy and safe New Year to you and yours sir.
Building a welder generator and needed some of these tips.
Big thanks for the tips, Jeremy.
Very clear on explaining!
You must be a teacher.?
Thanks for sharing!
Larry
Excellent vid Jermey, you answered my question and taught me a load of pulley info. New sub!
Great video with excellent information! Thank you for your time. It's amazing what folks can accomplish together !
Lot of great info......i need to save this video, have a great weekend Jermey
Your explanation is succinct, helpful and informative. Thanks for sharing.
Really love these purely educational videos! I’m working a lot with gt2 timing belts right now for the robot arm I’m building and I’d love to watch a video about timing belts with timing pulleys!
Oh, BTW that homebuilt bandsaw is awesome. I came to this site because I have a contrary rototiller and I thought it might be the design and belt wrap. After watching this I have figured it out!
Your my hero, it has taken 75 years of life to find you.
thanks dude! you've got this all under your belt
Thank You for this video! I am putting together an antique lathe with no motor pully that has a four groove pully on the lathe. I was about to make a big mistake in purchasing a multi-groove pully for the motor.
Definitely became a subscriber! Thank You Again!
You will still need a four groove pully for the motor. The motor pully will be installed in the opposite direction of the drive pully using only one belt. That is how you change the speed of the lathe rotation! I suggest that you look at a drill press belt system. Same idea, small motor pully to larger lathe pully gives less speed than the larger motor pully to the smaller lathe pully. It appears that you will have four speeds to choose from, depending on the material being worked. Just move the belt to the desired speed.
You have inspired me. I appreciate your thorough, yet simple explanation of a concept that has been complicated by others.
I find the best way to visualise the pulley ratios is to think of a bicycle. The fastest speed is a big chain ring with a small rear cog. For hill climbs a small front cog and a big rear cog does the trick. Great video thanks!
I first learned about belts and pulleys when I was modifying riding lawn mowers to go really fast. I really wish I would have seen this then it would have saved me a lot of frustration.
Again one more video for education!
Happy christmas and a good new year to you and your family!
Cheerio from Germany.
Excellent mate BETTER THEN ANY teachers I had
Thanks for the video :) I had a vague idea about some of that stuff but it was great to hear it spelled out so clearly.
If you are stuck having to use an undersized pulley, a notched V-belt is some help in easing the wrapping problem and/or over tightening the belt.
Another important consideration in getting good belt performance is to ensure the pulley shafts are parallel and the sheaves are aligned with each other. If you have belt problems that's the first thing to check.. even on a brand new piece of equipment.
Merry Christmas!
Thanks
Is that the purpose of the cogged v belts? To enable the use of smaller diameter pulleys?
@@hwingerrr5680 Yep.
Learned a lot from your video. Very well explained. Thank you.
very informativ and entertaining the same time, thanks for sharing your knowledge!
Nicely explained. You, sir, have earned another subscriber.
Once again, good content, keep up the good work.
Excellent video, well explained and has given me some ideas as to what might be wrong with my bandsaw!
I have an emergency supply fan with a motor with double adjustable sheaves. One of the sheaves is more open than the other. Problem I have is that when you create tension on the pulleys, one of the belts is tight and the other really loose. In order for the second belt to have some tension, the first one becomes suuuuper tight. This seems to be creating opposing tension on the belts, or tension on opposite sides of the belts (like you mention at around 2:26) , causing the motor to work harder and not blow the air it is intended to. So, my question is: would changing the belt size for one of the sheaves to create even tension help solve this issue? The fan runs only on emergencies only (thankfully we have not had any) and we had not noticed the potential problem with this setup. If I remove one of the belts and create the necessary tension on the one belt, the motor turns perfectly fine. I appreciate your feedback!
Hej, you one of the bests! Your videos are awesome. Thanks a lot and greetings from Germany.
Very well organized and great pacing. Thanks!
All you said was very correct and interesting but could I add there are other types of "V" belts and one in particular designed to be used with smaller pulleys. The clogged V belt is such a type especially the SPZ range will work satisfactory with pulleys down to two inches with a one horse power motor, especially useful on mini Lathes.
It's a great video. Here is a real world belt challenge: A garden tractor with a front mounted vertical shaft engine needs to power a rear mounted garden tiller. The V belt required is 70 inches long because it not only goes to the rear of the tractor, it also has to change direction over idler pulleys and a tensioner to drive a horizontally mounted pulley on the tiller reduction box. The problem is that the belt is so long under the tractor that it stretches and flexes and pops off under load. You cant have anything that hangs to low under the tractor and you can't overly tension the belt because of the electric clutch. How do you support the belt so it doesn't come off. This is pretty typical of older equipment.
Let the head scratching begin LOL
Find a place about half-way to mount a double pulley riding on 'pillow block' bearings then use two belts.
Ive got a racing lawnmower and i wonder why im always eating belts! I used to have a 6 inch pulley on the engine and a 2 inch on the transaxle, i would go through belts like crazy. Now i have a 10 inch on the front and a 3 1/2 on the transaxle. Ive had it like that for several months and only went through 1 belt, and the only reason it broke is because my rear pulley broke. It was only cast aluminum and didnt like the 10k plus rpms and the 20+ horsepower i was pushing through it :) im now thinking about doubling everything up to have more power delivery, i can tell the belt slips a bit because the pulleys get pretty hot. Ive definately learned a bunch!
Thanks for another vid. It's awesome when you pull out the text book.
6:19 Has anyone asked yet, why is the motor pulley at 6:19 offset from the key? Looks like the shaft key is at 11 o'clock but the pulley key way is at 1 o'clock.
This is exactly what I was looking for.
Thank you for sharing. I really enjoyed your video and learned a lot.
Oops, Jeremy. The last motor your featured that was belted to the large wooden pulley, the key way on the motor shaft was not aligned with the key way on the pulley. Is there some alternative method of securing the pulley to the motor shaft?
Really good video! Your explanation, along with the demonstration, made it super easy to understand some of the issues faced when dealing with v-belts.
Thanks for making this!
Love the video, Thank you. I always loved engineering but don't have all the brainpower to understand some concepts.
Very interesting observations and wishing you and yours a very happy Christmas 🎄🌨⛪.
Always good teachings. Thanks again.
Thanks for this video. You made this very clear.
You ave answered to my questions i had for almost a month
Hi Jeremy from Chile, how many hp is recommended in a motor to be able to easily cut 6-inch wood, because my 3/4 hp band saw stops a lot when cutting wood over 4 inches, thanks in advance.
Just discovered this channel - it's awesome. Great video, so useful.
Thank you, and welcome to the neighborhood!
I'm looking at possibly making my own metal lathe because I'm too poor to buy one so this is very helpful
Sooooooooo informative. EXCELLENT and many thanks!!
Thanks again for another informative video. I have no comments. I would just like to wish you and yours a Merry Christmas and thank you for all your help this year.
Thank you. Short video, but learn a lot.
Merry Christmas to you and yours Jeremy always like your explanations
Very interesting, thanks. So much to learn, so little time.
Thanks for sharing your knowledge! I learned a lot here.
Great information about v-belts and pulleys.
Thank you!
Really helped with my project 👌👌
This is awesome way of explanation
Dang dude. You are super smart! Thanks for the great info
Great video. Perfect explanations.