Homemade 2" X 72" belt grinder

[@AndysOutdoorAdventures]

As name suggests you have kept it simple and more than that this build serves the purpose , with variable speed and easy to operate mode , Great build cheers to you.

[@allymariachi9230]

i have a treadmill motor and by switching the lead wires it basically changes direction of rotation of the motor,cw to anti cw,try that and get the motor on the other side for easy belt changing

[@jameshall8914]

Thank you! I love the simplicity of your explanations of all the working parts of the machine.Something 98% of these videos lack!🤘😜🤘

[@Moronicsmurf]

For anyone wanna crown a skateboard wheel.. put it in the freezer for 15-20minutes, then do one crown, and then redo it for the next crown.

[@Simplelittlelife]

That's a great idea! Works fairly well?

[@Moronicsmurf]

With a really sharp HSS tool that has a polished edge it works really well.. chip breakers tend to gunk up so i just dont use em on urethane.

[@winterhorse290]

I used idler pulleys from Chrysler vehicles. It's the 1 inch wide ones. take two and put them face to face and just tack weld them. running a 9/16 bolt thru to hold it true. been using the wheels for 5 years without a problem

[@ejterhune84]

I don't imagine the bearings will hold up that long with side pressure. Buy you some ceramics or zirconium bearings.

[@alienh1701]

Best video I have seen on this subject! Thank you!!!!! Now I have to convince my wife that I need to re-purpose the treadmill.

[@jaredevans8565]

Hey guys I just wanted to share some of my fails and triumphs with the treadmill belt grinder build. Simple little life I love your build it was so simple and inspiring. With that I got a free treadmill and it was going to start a build went after taking it apart and putting it back together I fried the circuitboard. I thought that this was the end of my building was gonna have to find another treadmill and after some trial and error with the motor I realize that it was still good. I ended up finding a control switch on eBay for $30. This control has the transformer in it as well so it went 110 V AC to 130 V DC. Which matched my motor almost perfectly. With this I was also able to reverse the polarity of the motor so that it would spin counterclockwise. The significance of this is being able to mount the motor on the opposite side of the belt. The second significance to have you and there's separate control module rather than the controller that was with the treadmill is I'm able to get 100% out of the motor. With the treadmill controls I wasn't able to reach the 5900 RPMs that the motor is able to achieve . So far without being done yet or having a belt hooked up to this motor it works amazing. I wish I could show you guys picture but I will show a video when I get done.

[@jvmiller1995]

Can we see it now'

[@glenking3337]

That is by far the coolest and simplest grinder there is. And here I been salvaging treadmills only for their rubber for garage floor runners.

[@waltermurphy3870]

Thanks for great tutorial of your belt grinder. You as your name says keep everything SIMPLE!!! Thanks for keeping everything SIMPLE . Your the best MURF

[@charitiekbyrd1]

I've watched several of these videos on how to make a belt grinder and I have to say, Thank you for the tip about crowning the wheels, not one video explained why that's important. Thanks again!!!

[@mattbrown5511]

love seeing people repurpose materials. thank you for sharing your knowledge.

[@flaplaya]

"Nose to the grindstone".. So good to see a large community of hard workers, our forefathers and foremothers are proud :)

[@Grizzydan]

I use a treadmill motor for various tools. Sometimes a lathe, sometimes a grinder/buffer station. I'm building a 2x72 out of a riding mower frame with old roller derby wheels (got a whole bucket of them) picked up 20 skateboard bearings for $18 at a local shop, I doubt I'll have to actually put real wheels on it, but eventually I want to make some out of aluminum, so I'm saving all my cans and non ferrous metals and eventually plan to cast some in a soup can. Nice idea on the drive wheel. I never could get that pulley off the motor so I might try something similar.Thanks for sharing!

[@moonolyth]

I kinda like that you simplified several areas of this build including the frame. Great to see that you used the original drive plate by adding a tube face to it. I'm trying to eliminate the purchase of wheels as they aren't cheap.

[@Simplelittlelife]

Thank you!

[@JohnKlopp]

I work in a hospital that has a stress lab and a rehab dept that throws out old tread mills often. I never thought about it before, but I will grab the next motor I see out for disposal and start planning my next project. Thanks!

[@Simplelittlelife]

+John Klopp yeah you bet. They make a great option because they are variable speed and usually have a decent HP rating.

[@linmal2242]

You crazy knife makers! But I love your inventions. I want a decent woodworking linisher, so I need none of all that superstructure! Just a nice flat 4 -8 in wide linisher, 3ft long! Will take your good advice and run with it.

[@Simplelittlelife]

Right on👍

[@douglasalan7786]

Nice simple build you built. A dream machine for most people, to be sure. Just goes to show it doesn't take 2 grand to own an excellent belt grinder setup. I built mine 48". Contact drive and idle/track. Why ? The belts wear out faster(sounds goofy) and they track better than a 3 or 4 wheel setup. When my 36 grit is duller, I toss it aside. You use yours for far more cuts after its half dull. I make knives so 36 grit gets put to the side for welding stuff at about 25% loss and a new one goes on for cut consistency.I also made mine with a 1 1/2 wide wheel setup. I like narrower for the style knives I make. Same price for custom belts and I find flawless splices that way too.

[@Simplelittlelife]

cool beans.

[@Wolfsdenforge]

I'm building one right now and you're design has a few features I like better than what I designed, thanks for the video!

[@Alcarria92]

Mate well done love it , I’m building my one next week

[@southernblueblood5402]

Are there specific measurements need for the distance between the flywheel and the planten, that's my biggest question. Any help you can give would be greatly appreciated.

[@coreyriggle]

I was not expecting the treadmill motor controller! but great idea.

[@Simplelittlelife]

Thanks. Works well and it's easy:)

[@AlanAlanAlanDave]

I’m thinking of a simple post with a planten bolted to it and bolted to a surface inline with with the motor. Fix the tracking bar and wheel to the post with a spring or strut fixed on the post. Most simple design and depending on distance from motor any length belt can be used.

[@luismorales4617]

Cool machine, cool video, and cool about " The Chupacabras"...

[@bertmarchand238]

I understand the wanting to see if it works part about not taking time to paint. I'm the same way.

[@liamstone3437]

So how far apart do you have the pulleys on the business end? How long is your platen from top to bottom? What is the diameter of the wheels you made? What size shafts are you using on your pulleys? What size box tubing did you use? Thanks for the video and for talking about your build - so many of these videos seem to show off skills without any interest in sharing enough info to actually duplicate the builder's efforts. Thanks for sharing.

[@conservativemacro80]

nice video, im 16 and really want to start making knives, I welded up a forge and know I need to get some files and a few other things to start. Eventually will get more tool and stuff as I get money. Thanks for the knowledge

[@Simplelittlelife]

+Conservative Macro You bet! That's awesome that you welded up a forge. That's a huge start! That's where the industrial revolution started. Good luck gathering the rest of your gear and getting started! I'd love to see how it's going for you when you get it all sorted out. Cheers!

[@ChuckNorrisUltra]

That's the best VFD I've seen so far!

[@malikon7450]

I love that thing man. You did an excellent job. I like how you applied the K.I.S.S. (keep it simple stupid) method in this build. It isn't over engineered.

[@idahosagebrush5662]

Good job on your build... And thanks for the video with details. I'm a cheapskate too, and I have a treadmill motor waiting for me in the shop, too... Using a DC motor is, in my opinion, far better than an AC motor. The advantage of a DC motor like this is that it delivers full power at all speeds. I bought my wife an industrial walking foot sewing machine for doing heavy vinyl tarp material. It has about a 1 1/2 or 2 HP DC motor with an electronic speed controller. Her sewing machine motor has a small selector knob on the motor housing for coarse adjustment of dead slow to full speed ahead. There is a separate foot controler for fine adjustment speed, which would be simple to adapt as it's just a potentiometer on a mechanical linkage. Awesome power to sew through 3/4" of heavy material with thick thread without bogging down or stalling... If anyone wanted to use a new motor without the spare treadmill parts and a rewire job, they can be bought online for less than an AC motor w/o any speed control. Look online for industrial sewing machine suppliers. Of course, the drive wheel setup would be different than this, but no multi speed pulleys would be needed ...

[@Simplelittlelife]

+Idaho Sagebrush ah yeah that would be a good option too. Last week I mean my belt grinder for probably 5 hours a day 4 days in a row and I'm amazed at how well it handles it. I did a lot of heavy hogging down on stock for a larger batch of knives I had to get out. Really a decent option. Cheers!

[@joeydesveaux9075]

nice job man! i was not sure about using a tredmil motor, but now ill search for one!!

[@Simplelittlelife]

Thanks. Yeah, it works really well. I've used mine for about 4 years now or something like that and I'm shocked how well it's done for me. I think I'm starting to come close to end of the motors life, but I'm really starting to use it a lot more every day and I certainly can't complain about how it's done for me. Hope you find one to use. Cheers!

[@jamesmclane2826]

Great job with your grinder 🙏thanks for doing the video😎🤙🖖

[@frost2621]

Really cool project I am really considering making one of these. its seems like you got a really nice set up there! Great Video!

[@Simplelittlelife]

+Cole Smieja Thanks, I'm glad you liked it and hope it helps. Cheers!

[@mrirondance]

Nice simple design , good video thanks . if you don't mind what are the general measurements. length of tubing and so on :)

[@Simplelittlelife]

+barry connolly I don't have them off the top of my head but I'll get them for you in a couple days. Cheers!

[@andylangton780]

I’ve wanted to build a 2x72 belt sander for a while, I have treadmill motor but was wondering if you had any plans?… I guess I could just figure it out but I really liked your design. Thanks for making the video and sharing your ideas🙂

[@OldGuyOnBass]

I learned a lot from this vid - thanks, man.

[@Simplelittlelife]

Glad to hear it! Thanks 👍

[@TheFishstick9983]

man that's an awesome rig ! I was wondering how possible it was to fab up one of these .. .and boom there it is! thanks for the video. now i don't have to buy some cheap one i can make a nice 72incher

[@Simplelittlelife]

+Mike G you bet! A hand made one will last much longer than a junkie purchased one. Plus, it'll most likely be made of much better materials so modifications as you see fit will be easy.

[@billys652]

Hello from Australia. Great job on the belt sander. Can I assume that there's a gap between the drive motor fly wheel and the body of the horizontal member? I couldn't actually see how the belt slipped past when fitting and removing! Thank you.

[@Simplelittlelife]

Hello back at you from Canada eh? Yes there is a gap. Not huge so I actually have to slip the belt in there but it is there. Cheers!

[@ricikeri]

Great creativity....keep up the good work and disregard the "know it all trolls"...some people just aren't happy unless they can bring somebody else down...

[@Simplelittlelife]

Thanks. I really appreciate the support. Cheers!

[@bennyhill3642]

Thank you for all the info😇Great job🖒

[@Simplelittlelife]

You’re welcome and thank you for watching!

[@robertverduzco4351]

Hi thanks for the video and I would LOVE LOVE the specs on your belt sander so I can attempt to make one

[@Simplelittlelife]

I'll see about getting a video with some more info on it. Cheers!

[@eoghanruane4441]

hi i have two questions 1.where can you get other types of 2hp motors and 2.could this be done with wood

[@djstanstillmke]

if you have a lathe and want to machine rubber: hand grind your tool steel blank by adding a deep chip break channel and a razor sharp cutting edge. You want to get the chip away from the workpiece quickly and you want NO tool pressure while doing it..I always end up making mine into 45degree tools because I would need to chamfer a corner. Try it next time then comment if it worked for you..

[@jaygallagher8064]

Thank you for all the detail information. Very nice!

[@salirezakm]

Hey, Jeremy! I'm thinking about having a belt grinder made because of economic reasons & I've got 3 questions :D 1- could you tell me how many watts does the motor produce and what's it's maximum rpm, please? 2- do you think a slightly weaker (cheaper) motor could also do the job? 3- how significant was the total cost difference between making this device, and buying a manufactured one? Thank you very much

[@larrybud]

If you look at 2:46, it's a 2hp motor, which is ~ 12 amps at 120v single phase.

[@countryenduro4504]

I am thinking of doing this also what issues did you run into and what should I avoid in order to make the build less of a hassle Thank you in advance

[@Simplelittlelife]

Not really. Just get all the materials ready before you start (wheels, tensioning spring or system etc) and it's pretty straight forward. Cheers!

[@Simplelittlelife]

Oh, also know how you are going to mount it. That was one thing I didn't think about until I was almost done, and it would have probably made it a little easier.

[@lucianosalvador7931]

I liked it very much and I will make one like it, I ask you have how to make this template of the knife of the video available?

[@travisrider7314]

Thanks for the detailed video. I've been wanting to make one.

[@hunterdeem258]

Very neat grinder.

[@Simplelittlelife]

+Hunter Deem Thank you kindly!

[@julianwebb8680]

I’m planning on building one myself. Some of the online videos say that the motor/control board have to be protected from the metallic dust that the grinder creates. One guy said the motor drew in air/metallic dust and short circuited the motor. I see you posted this a few years ago. How is it working out?

[@thomshere]

Great video as is all your others! How much crown did you put on your belt wheels would you say? Thanks advance!

[@prmaddock]

may be asking a lot, but could you take measurements of the square tubing for this and post them?

[@billblake6954]

Great overview - thank you. Any chance you can provide some data? diameter of the drive wheel, RPM of the motor at Maximum, what grit is your belt and do you use different grits as you finalise the profile of your blades? Also, do you ever use the motor at full speed or is that just a bit too fast?

[@Simplelittlelife]

Thanks, and you're welcome. The drive pulley is a 6" (just happened to be the size of pipe I needed to machine to fit over the flywheel that was already on the treadmill motor. I actually run it quite slow compared to what it can do. The treadmill controller has buttons that reference a preset speed (in mph, for the treadmill belt) and I typically grind at 3 mph, while there are buttons that go all the way up to 10 mph. There are also little up and down arrows that will allow you to fine tune the speed and those are handy when I'm working on wood and handle materials when I was a slower speed to I don't start to burn the material I'm working on. I might do a video with all the dimensions and specifics of the grinder. I get quite a few questions about it. Cheers!

[@billblake6954]

Good info - thanks again. If I can be a pest. Is there an RPM listed on the motor specs. With that I can calculate a belt speed etc. G'day from Downunder.

[@TheKajunkat]

3 miles per hour should work out to 44 feet per second if I did my math right. mile =5280 feet and hour is 360 seconds. Another way to do it would be to add 14.7 feet per second for each mile per hour. The pulley is a little bigger but that should get you close. If you knew the original pulley size you could figure a correction factor to the 6 inch pulley

[@Simplelittlelife]

There is a way to figure out the belt speed of the grinding belts with math, but the MPH designation on the treadmill controller also accounted for the fact that there was further speed change from the pulley that was on the motor to the pulley that was on the treadmill belt shaft. Without those measurements, you'd need to know what the 3 MPH sets the RPM of the motor to. I put my tachometer on it a while ago and i think 3 MPH is closer to 60 feet per second. I suppose I could just check it again though. All I know is that at 5 MPH, it's way too fast to grind on (faster than my KMG with 3600 SFPM) and feels like it's going to fly apart:) Scary fast.

[@MadMaxWill]

Superb! I've been looking for a variable speed 72" plan that's affordable. Except for that part about buying a lathe.. Lol! Leaving the original speed control hooked up is genius. Do you think a smaller drive wheel would be feasible? Maybe a $50 dollar 5" bought wheel with the corresponding bore and key-way size? I like the design, but forging a fit seems a little over my head. Great share!

[@Simplelittlelife]

Glad it helped. I think a smaller wheel would work for sure. When I'm trying to hawg off max material during the initial grind, I think I only run up to a 6.5 out of 10 on the speed dial. Obviously it varies for treadmill to treadmill but I've never come close to using all the speed that this one has. Smaller wheel means more torque and might even be better for the motor and bog down less with the heavy grinding... Cheers!

[@MadMaxWill]

+Simple Little Life This has me excited, my 1x42" just isn't cutting it now. You make a good point about torque, but I suppose a smaller drive wheel would also increase the speed minimum. If you get a chance I'd be interested to know the diameter of your drive wheel. This is going to help a lott of people get into the hobby.

[@Simplelittlelife]

+Maxwill Beryl Hey just FYI, the drive wheel that I am using is 6 3/4" diameter. I just measured. Cheers!

[@sandotrinistories.7820]

Great video, you have used many common items to create an excellent sander. You are a great D.I.Y. source.

[@PiefacePete46]

Excellent, really useful machine. Great video thanks.

[@GnarledSage]

Very nice. How much did you end up spending on this? You said you even bought a lathe just for this project?

[@merleswanger5749]

How long is the tubing from the motor to the front pulleys

[@har99ley]

Do you have a site with measurements I'm looking to do something like that.....? nice build Thanks

[@peterchamberlain2922]

mate can you put a detailed drawing on the internet I think your 2 x 72 grinder is fantastic , I am just getting into knife making

[@billymartinozarkmountainfo225]

I am making one now out of a tread mill. I will do the motor the same way on the pull. Haveing it with such a big one it will fix a lot of problems others are having with it not throwi g sparks like they should. Thanks for the idea. Send u pic or vid when it's done thanks

[@MrJack-yx6nm]

Does the belt have contact with the platon (however it's written) or is there some space between them? And how did you figure out the design for your belt grinder so that the belt would fit good?

[@Caughtitoutdoors]

I'm in the process of building a 2x72. Is there any reason why I shouldn't build it with the belt on the left side of the grinder?

[@shnitzelpickle1]

cool build looks pretty solid

[@Simplelittlelife]

+Richard Maor Thanks!

[@aaronswank5558]

Hey man, thats was very informational, awesome video man!! Thank you.

[@Simplelittlelife]

Sweet! Thank you so much! Glad it helped you. 👍

[@karf450]

Treadmill motor and controller is very nice. Make another and sell it.

[@Simplelittlelife]

Thanks. If I had more time I might be tempted to make some more. I know that when I was looking to buy a used one (several years ago) they wouldn't last more than a few hours on local classifieds. Certainly a market for them. Cheers!

[@FantazzticoRendidorMaravilloso]

Very nice work¡¡ My question is : ¿It is really impossible to align the belt using straight wheels, or just it´s difficult or hard to do it? ----Perhaps if i do a groove to ´´seat´´the belt about 2 millimeters deep will fit in line¿? I noted a bump in the belt and of course is not the same to use a perfect flat grinder belt , instead to use a ´´bumped´.May be for rough pieces will work well but in very precise ones i think a flat belt will give better results. ¿What do you think about it Master.? Thanks.

[@Simplelittlelife]

+Fantazztico Rendidor Maravilloso I'm certainly no Master, hahahaha, but I used to work for a company that manufactured and installed airport baggage handling system. Those big huge conveyor belts are pretty much the exact same thing as a belt grinder and we crowned all of our pulleys and it made a huge difference. It would be possible to track a belt without crowned pulleys but you would have to have everything so precisely square and then have the ability to micro adjust for discrepancies between one belt to another. If you machined a fairly heavy groove it might keep the belt in there, but it would wear the belt quite badly. For the amount of work it is to crown a pulley it saves so much time and make the machine work so much better. I would be possible to do without crowning the pulleys, but it would be much more difficult. Also, the belt is designed to flex and arc and then come back to flat. When it's running on the platen, it is as flat as it would be if you had perfectly flat wheels. The crown in the wheels does not affect the belt where you use it for grinding. Cheers!!

[@bigfatbill5187]

I would love to see how you made the aluminum wheels. Was it difficult on the lathe?

[@Simplelittlelife]

+Tim Coombs No it wasn't hard at all, but I did work in a machine shop for years. Maybe the next time I need to make some new ones (thinking about making a horizontal belt grinder) I'll do a video on making them. Cheers!

[@AustrianJager]

Very well made belt grinder!

[@Simplelittlelife]

Thank you!

[@msblades5382]

Simple little life I am wanting to diy a grinder and want to use a treadmill motor like yours.The question I have is have you had any issues with the motor due to the fact I have heard they are not ideal on account they are a mag. drive and not sealed. Is your grinder still running on this motor? I have seen your more recent videos and it seems you are using a different grinder. Any help will do. If I can use this motor for a while and be able to upgrade or diy another. possibly seal the motor in a box?

[@ProfessorCastle]

Shan Moldovan I made a grinder with a treadmill motor. I just built an enclosure for mine. Fan cooled with air filters. But the motors are dirt cheap. I get them free. So if one goes out is easy to replace.

[@lghusky2014]

Awesome, the motor is genius!! love it and i find me a treadmill

[@analog56x]

thats freaking genious! i was trying to think of what to use for a motor speed controller... now im searching my local area for treadmills haha! i gotta rebuild my belt grinder... tiny 1/2hp motor with a 2x42 belt, and my platten is tilted back about 20* so its difficult to flat grind... i also have no table haha! its worked so far, but i want something better now...

[@ixamraxi]

You only need one crowned pulley, more than one crowned pulley could amplify even the slightest mis-alignment between the different pulley's, causing the belt to oscillate back and forth (due to the multiple crowned pulley's acting against each other).

[@Simplelittlelife]

No. They won’t oscillate back and forth. Ask me how I know....Amra.

[@ixamraxi]

@@Simplelittlelife Given how many people have gotten rid of a second crowned pulley and in the process eliminated oscillation of the belt, it seems reasonable that this can be a cause of belt oscillation. I did not imply this is the only cause of belt oscillation, and I happily agree that if you've done a good job in aligning your pulleys, even multiple crowned pulleys wont/shouldn't oscillate. The point is simply that multiple crowned pulley's is not necessary, requires much higher levels of precision during manufacturing, and doesn't produce significantly improved results over a single one. Having built my own grinder, I can attest to the fact that a single crowned pulley is more than sufficient to track a belt perfectly. But, I'm always one to hear peoples own experience, so please; tell me how you know.

[@StraightCutGears]

How long did your motor last?

[@Simplelittlelife]

Still

[@louiscypher7090]

Why not use the motor from a wetsaw then run the drip Lines just above where the blade makes contact with the belt?

[@paschalia100]

very nice grinder

[@mcorrade]

great job. I use to work with metal and really miss it but, my new passion is wood and I made a nice small sanding belt sander from wood, some metal but I think you thoughts on the longer belt cooling faster is right on so I think I'm going for 2x72 thanks!

[@toppertruthio]

p.s any chance of a part 2 where you design the anchorage?

[@LonniesGarage]

What is the inside and outside diameter of the steel tubeing your using

[@toddleshane]

Where do you buy larger tube steel like that? I've never really needed anything larger than what you get at lowes or hd, and the only places I can find seem to be mostly interested in industrial clients. Great build by the way. Looks great.

[@Simplelittlelife]

Metal Supermarkets is a great place for all kinds of steel, and they sell to the person off the street just as well as they do to the big manufacturing companies. (actually, I'm pretty sure they don't sell to big manufacturing companies). They are really great and have a bunch of locations across Canada and US. I hope there's one near you! Cheers! www.metalsupermarkets.com

[@toddleshane]

Oh excellent! Yes looks like there is one about 40 mins from me. That won't be to bad a drive for the frequency I need larger steel. Thanks!

[@Simplelittlelife]

tlane567 you betcha!

[@bertmarchand238]

I'm in Two Hills Ab. And was wondering what you think about a 1&1/2 horse motor that runs at 3450 rpm and if it would work alright with a 4 inch drive pulley.

[@Simplelittlelife]

Hey Bert, yeah, I think that would work for sure. I'm actually just uploading a video where I respond to your question. The motor I have is 3470 RPM, 1.5HP and I have a 4" drive pulley. I have a ratio from the motor shaft to the grinder drive shaft that isn't quite 1:1 so it changes the speed a bit, but my grinders running at 3332 surface feet per minute. Which is great for knife making. If you have the drive pulley running at 3450 RPM you'll get pretty much the same speed (maybe a bit faster) but it will work great for you. Cheers to a fellow Albertan! (I bought a truck that was originally sold from a dealer in Two Hills. '81 Chevy)

[@Mikeyfix]

when you had this turning fast and started to grind your jig I think I heard chattering ,if so do you reckon heavier building pieces

[@discflight]

Dude! Thanks for sharing this - simple, informative and really useful 👍

[@marcusjames2139]

subscribed for this video. really good. Definitely going to try

[@GiorgiKhabeishvili]

so all 4 wheels/pulleys are crowned? thanks

[@Simplelittlelife]

nope. Just the drive wheel and the tracking (the one on top) wheel. Usually the wheels on the platen are not crowned. Even on my purchased KMG grinder the platen wheels are not crowned. Cheers!

[@GiorgiKhabeishvili]

ok got it. thank you very much!

[@beachboardfan9544]

Wouldn't a concave crowned pulley track better then a convex crowed pulley? I would think a convex shape would make the belt want to slip off of one side where a concave would make it want to fall into the center.

[@PiefacePete46]

The belt will always try to climb up the slope to the highest point, which is the middle of a crowned pulley. This makes it self-centering. With a concave pulley the belt will climb towards the edge, and come off. If you have a V-belt drive and the pulleys are not perfectly in line, it will throw the belt off because the belt climbs out of the V. Study a picture of 100 year old farming equipment, many used large flat belts with crowned pulleys.

[@beachboardfan9544]

John Colvin Its interesting, I wonder whats taking place to cause this effect? It seems counter intuitive to me.

[@karlhurtubise7073]

The belt stretches a bit on the higher side of the crown, and travers faster than the unstretched side. This applies a force to the wheel to one side (since the wheel can't be pushed, the belt tracks instead). It kinda works like a car , if a wheel goes slower on one side, the car will be pulled towards that side, exept in this case, the car is the crowned pulley, and since it can't move side to side, the force is applied to the belt instead (opposed to the direction that the wheel would go,thus pushing the belt to the higher point of the pulley). As it gets to the top, both sides of the rubberband are at the same speed, thus it stops it going any further.

[@kylemacdougall1410]

brilliant video, im inspired to build one myself. thanks

[@savvybuilds]

Thank you!, Great info :).

[@ANTThePANT79]

I'm curious about this... I got a treadmill motor and did the same thing but when i put any load on the motor it stops and gives me an error code. Ever had this happen to you?

[@drakereuter90]

What grit sand paper do you use for the initial grind on the bevel

[@timmccarthy1780]

Drake Reuter between 36 grit and 60 grit

[@VincesEngines]

Nice job

[@mikemiller5984]

I might be slow or just missed it but, how do you change the belt?

[@ClownWhisper]

You should let everybody know that if their control panel is fried or they just got the motor for some reason it will run on I believe 48 and 24 volts and I think just a handful of amps I can't recall exactly the amperage you need but basically I run mine on a 48 volt Tayo yoden that has 24 to and it runs at about half speed at 24 but it loses a little bit of the torque as well. But with that flywheel you don't really feel it. So you can wire it up with just a switch for 48 or 24 volts or for that matter. See you even if you don't have the controls or the control board with the Transformer because that fries often you can still run it just for the power supply.

[@NuManXplore]

I am finally getting around to watching a few more of your vids. That belt grinder is awesome! I knew some guys used treadmill motors, but I had never thought about keeping the variable speed controls connected to use for the grinder - thats a great idea. One question, I noticed that the belt is tight against the platen, and even slightly angled near the top wheel, do you find that the back of the belts wear faster because of that? Just curious... Cheers!

[@Simplelittlelife]

+NUMan14 That was because I changed the top wheel from when I had originally built it. I think it probably does cause the belts to break down quicker but I haven't actually noticed a difference. Ideally though it was better when I first made it and there as very little difference between the two. Cheers!

[@nicholasduncan3921]

Any info on where to get parts to build a belt saw

[@heavymetalworks6375]

I thought that the wheels on platen attachment was to be plum with the plate. It looks like your wheel are set back and the plate stick out by the wheels. i would think it would ware the plate and the belt out faster like that. but that my 2 cents

[@Simplelittlelife]

+Adam Lewis yup, you're absolutely right. The top wheel is one that I machined and the stock that I had kicking around in the garage was smaller than the longboard wheels I originally built the grinder with. I needed to get a knife out for a friend and decided to make the wheels out of smaller stock anyway and after several months (probably 20-25 knives) I really don't notice any increase in belt wear. Obviously it will eventually be noticeable that it's wearing on the platen, but by then I'm sure I'll have built another grinder. There are a lot of changes I'd like to make. But you're spot on, those wheels and the platen should be in line with each other. Cheers!

[@RJB_FixinStuff]

If this is an MC 60 speed controller or similar you can ditch the big bulky panel and use a simple 5k potentiometer and a knob. Message me if you need assistance.

[@Paracorder]

Can I buy this off of you now that you have a new one? My 1x30 broke and it's not worth getting another because I'm at the transition stage of being limited by tools and money. Thx

[@Simplelittlelife]

I actually still use it. I have this one set up for my handles and kydex and the other set up for hard grinding of the metal. Since the other one is a single speed (for now) I have it running pretty fast and need a slower option for the other grinding work I need to do. Sorry about that.

[@Paracorder]

No problem it's yours. Just keep me in mind when the time comes. Loved your 30 day challenge

[@Simplelittlelife]

Thanks. I will certainly keep you in mind. Cheers, Jeremy.

[@towoperations]

I'm not sure if anyone will read this that can help but I have a okay shop and I just made my first knife out of a large wrench. I'd love to show it to someone with some experience to grade it and let me know what they think. I haven't quenched it yet so the steel is still workable. I have a mediocre forge that I built myself. I heard the gentleman in the video mentioned that he measured his bevel. For this first night I decided to eyeball it and I believe it turned out pretty damn straight. So I have questions about that as well I'm not looking for a fluff review just the no BS how did I do. You can reply to this comment to get ahold of me.

[@patrickwagun8713]

How mutch did the whole build cost?

[@bobbyschwarz4074]

Any suggestions for someone with NO welding equipment or skill?

[@pantelissaliaris5398]

got a question. i am making a belt grinder myself now and i haven't decided what belt to make it to fit. in uk where i live i found a website with a variety of belts with good prices so i made my rollers to fit a 100mmX1575mm belt but i think a 4 inch/100mm belt is an overkill. i am thinking of making them to fit a 75mm belt and can also fit a 50mm belt hopefully (a lot of variety and cheap belts at 2"/50mm i have to admit). are you happy working with a 50mm/2" belt? would you go with a 3" if belts were readily available? thanks

[@ProfessorCastle]

Pantelis Saliaris 2"x72" are the norm for knife makers I've talked to online. That's what I use. There seems to be a lot more belt variety in that size.

[@snipes3234]

did u ever have a problem with your grind lines being wavey?

[@Simplelittlelife]

At first I did, but with practice you kind of learn how to avoid that. Having said that, I find it much easier to get really straight and crisp grind lines with my new KMG grinder. Cheers!