# belt grinders



## scott.livesey (Dec 8, 2017)

this was started in The Kitchen Knife section when talking about women and knives, kind of a sharp turn off the subject.
My experiences:
I am an amateur maker with a small shop. I have 4 belt grinder/sanders. the main one I use working with steel is a Wilmont LB1000 2x72 with multiple motors, drive wheels, and variable speed. for finishing, sharpening and polishing, I use an 800 rpm Leeson 1 hp 3 phase motor with a 3" drive wheel. power is provided by a Leeson Speedmaster inverter/variable speed drive that converts 120 vac to 3 phase 240 vac. It cost about $1000 when I assembled it. the grinder without motor is $800 plus shipping and is a kit that takes about 2 hours to assemble. it will accept any 56C motor and is set up for direct drive(no pulleys). the motor was a factory special order that I found on eBay for cheap, so was the drive. with this motor/drive wheel combination, I can easily run at belt speeds as low as 300 sfpm without stalling or overheating the motor. low speed is critical for wet grinding, belt life and prevention of over heating the blade.
I have a Craftsman 4x36 with a 6" disk that works ok but is one speed, about 1100 sfpm. I use it occasionally for steel when doing rough shaping. I have a Porter-Cable 4x36 with 8" disc that is high speed and only used for wood. I have a Buehler 4x36 wet lab grinder that is awaiting conversion to variable speed. I welcome questions.


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## K813zra (Dec 8, 2017)

I know pretty much nothing about power tools. I am a hand plane kind of guy at heart. However, I do have a cheap harbor freight side by side belt/disk grinder. It works to play with. What are your thoughts on a good grinder for someone who never intends to be more than a hobbyist. Maybe thinning out ebay forgecraft projects and such? Maybe a knife blank or two from various outdoor suppliers. 

I know it is a vague question but it is what I have.


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## scott.livesey (Dec 9, 2017)

the way most inexpensive belt sanders are constructed, it is a project to try and modify. the main issue is speed control. speed control can be done by changing the motor to DC with DC speed control or a 3 phase motor with a VFD. even if you shop well, either option is probably $200 for just the motor and drive. then you have to figure out how to mount the new motor. I have thought about modifying my Craftsman 4x36, about the same as the harbor freight one, but you just end up putting lipstik on a pig.


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## LifeByA1000Cuts (Dec 12, 2017)

Would almost be interesting to try and use some kind of tachometer sensor plus negative feedback and use the existing motor...

(NB this is just an idea thrown in. Don't "just try" that with a power tool that could very well throw things across the room if the speed control went into an unstable/oscillating feedback behaviour)


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## scott.livesey (Dec 12, 2017)

i understand. unless it is a 3 phase or DC motor driven by an adjustable drive, variable speed is not feasible. be aware that a belt or disc grinder at "low" speeds can still take the blade from your hands and bury it in the floor. luckily my shop floor is plywood and the blades and me were not damaged.


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## natto (Dec 13, 2017)

scott.livesey said:


> i understand. unless it is a 3 phase or DC motor driven by an adjustable drive, variable speed is not feasible. be aware that a belt or disc grinder at "low" speeds can still take the blade from your hands and bury it in the floor. luckily my shop floor is plywood and the blades and me were not damaged.



I would like a belt drive with different gears. Specially for wet grinding. Keeps electric dry!


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## aboynamedsuita (Dec 14, 2017)

scott.livesey said:


> ...I welcome questions.



what do you think of my idea, or am I an idiot? I am working on heavily thinning a knife (large cleaver), and it is painfully slow by hand... to the point I don't even want to look at it. So I bought a 3x18" variable speed (around 400-900 fpm) belt sander, the plan is to find a way to mount it so I can do the bulk of the work on this before going to the stones. Stupid idea? :dontknow:


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## scott.livesey (Dec 15, 2017)

aboynamedsuita said:


> what do you think of my idea, or am I an idiot? I am working on heavily thinning a knife (large cleaver), and it is painfully slow by hand... to the point I don't even want to look at it. So I bought a 3x18" variable speed (around 400-900 fpm) belt sander, the plan is to find a way to mount it so I can do the bulk of the work on this before going to the stones. Stupid idea? :dontknow:



is reasonable idea. i guess you could mount it belt side up in a vise and set the speed. if you can find a zirconia belt it might go faster. use lots of sharpie marks so you can see what you are doing. have a large container of water nearby so you can dip the blade ofter. hardest part will be keeping the grinds even on each side. I picked up an old Foster Bros. WW2 vintage cleaver and used a 4 1/2" right angle grinder to remove rust, stains, and dents before finish grinding.


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## jessf (Dec 15, 2017)

I made around 15 knives with a cheap belt sander. Very doable. I still prefer the width of a 3x18 belt to my 2x72.


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## milkbaby (Dec 15, 2017)

I think jessf was using one of those hand held belt sanders mounted in a vise or some other way. If you search, you can find the pic I believe. As Scott mentioned, a bucket of water to keep the blade cool is important. A thick cleaver will be a heat sink but the thin edge can still overheat quickly if not careful.

Edited top add: as you can see, jessf chimed in while i was writing... :laugh:


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## K813zra (Dec 15, 2017)

milkbaby said:


> I think jessf was using one of those hand held belt sanders mounted in a vise or some other way. If you search, you can find the pic I believe. As Scott mentioned, a bucket of water to keep the blade cool is important. A thick cleaver will be a heat sink but the thin edge can still overheat quickly if not careful.
> 
> Edited top add: as you can see, jessf chimed in while i was writing... :laugh:



What do you use to grind your projects? I'd love to see a "process" thread, maybe you already have one. But I was following along with a few you made and posted elsewhere.


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## jessf (Dec 15, 2017)

K813zra said:


> What do you use to grind your projects? I'd love to see a "process" thread, maybe you already have one. But I was following along with a few you made and posted elsewhere.



if the question was directed at me then you can read some of the following. You will need to first install the google chrome plugin Dave posted in the link below as all the photo links were broken when Photobucket crapped on everyone's parade. 

http://www.kitchenknifeforums.com/showthread.php/34163-Photobucket-Fix

http://www.kitchenknifeforums.com/showthread.php/26661-WIP-Honesuki?highlight=
http://www.kitchenknifeforums.com/showthread.php/26952-WIP-Nakiri-Gyuto-then-Birds-Beak?highlight=
http://www.kitchenknifeforums.com/showthread.php/27384-WIP-Western-full-tang?highlight=
http://www.kitchenknifeforums.com/showthread.php/27783-Another-Gyuto-WIP?highlight=
http://www.kitchenknifeforums.com/showthread.php/28034-WIP-Western-hidden-tang?highlight=
http://www.kitchenknifeforums.com/showthread.php/28165-WIP-Gandknife-the-Grey?highlight=
http://www.kitchenknifeforums.com/showthread.php/29199-WIP-Not-a-Gyuto?highlight=
http://www.kitchenknifeforums.com/showthread.php/28596-WIP-The-tusk?highlight=
http://www.kitchenknifeforums.com/showthread.php/29898-WIP-Petty?highlight=
http://www.kitchenknifeforums.com/showthread.php/30262-GIP-Paring?highlight=
http://www.kitchenknifeforums.com/showthread.php/30309-WIP-Bread-knife?highlight=
http://www.kitchenknifeforums.com/showthread.php/31767-WIP-Forging?highlight=
http://www.kitchenknifeforums.com/showthread.php/34074-Knife-17-Brute-de-forge-chef-3?highlight=

in short, a $60 belt sander can go a long way in making a knife from scratch, much less thin an existing one. 2x72 grinders and the like are best for faster removal and higher production.


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## K813zra (Dec 15, 2017)

jessf said:


> if the question was directed at me then you can read some of the following. You will need to first install the google chrome plugin Dave posted in the link below as all the photo links were broken when Photobucket crapped on everyone's parade.
> 
> http://www.kitchenknifeforums.com/showthread.php/34163-Photobucket-Fix
> 
> ...



That works. I know Milkbaby makes knives too and was curious there as well.  But I like looking at projects! Thank you for sharing and answering my question!


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## LifeByA1000Cuts (Dec 16, 2017)

Anyway, what is the noise level working with the cheap sanders? Something that will immediately have the neighbors knocking on the walls, or very civil?


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## jessf (Dec 16, 2017)

Less noisy than a vaccuum cleaner. If youre working in an apartment or indoors id be more worried about setting off the fire alarm. More of an issue once the blade is hardened and throwing sparks. Best to work outside.


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## milkbaby (Dec 16, 2017)

Kit, if you were asking me, I use a relatively cheap Grizzly combo sander that has a 1x30 belt and a 5" disc. It's not very efficient, but I don't have the funds or space for a 2x72 right now. While some people discouraged me from starting by hand with files, lots of people start that way and some stick to that. 

I'm an apartment dweller and never had a complaint about the sanding noise. It does sound loud to me while I'm doing it though. I did have a neighbor kindly ask me to delay hammering as they wanted to take a nap.


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## K813zra (Dec 16, 2017)

milkbaby said:


> Kit, if you were asking me, I use a relatively cheap Grizzly combo sander that has a 1x30 belt and a 5" disc. It's not very efficient, but I don't have the funds or space for a 2x72 right now. While some people discouraged me from starting by hand with files, lots of people start that way and some stick to that.
> 
> I'm an apartment dweller and never had a complaint about the sanding noise. It does sound loud to me while I'm doing it though. I did have a neighbor kindly ask me to delay hammering as they wanted to take a nap.



Ah, I see. I am a live in the middle of nowhere dweller! My chickens might complain but then I'll eat 'em. You do nice work though!


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## aboynamedsuita (Dec 16, 2017)

scott.livesey said:


> is reasonable idea. i guess you could mount it belt side up in a vise and set the speed. if you can find a zirconia belt it might go faster. use lots of sharpie marks so you can see what you are doing. have a large container of water nearby so you can dip the blade ofter. hardest part will be keeping the grinds even on each side. I picked up an old Foster Bros. WW2 vintage cleaver and used a 4 1/2" right angle grinder to remove rust, stains, and dents before finish grinding.





jessf said:


> I made around 15 knives with a cheap belt sander. Very doable. I still prefer the width of a 3x18 belt to my 2x72.



This should be possible, I got some zirconium diablo belts in 36 and 50 grit, could get higher too

My cleaver is a moritaka so the softer cladding should hopefully be easier by power sanding than the hand sanding I was trying the core may be a different story though. I pretty much want to raise the shinogi a lot and make the angles more acute


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## scott.livesey (Dec 16, 2017)

the zirconium belts will eat the core just fine. i use them on tool steel at Rc62-65 with no issues. 50 grit is a little coarse. see if you can find any at 100 grit.


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## aboynamedsuita (Dec 16, 2017)

Shouldn't be a problem, Home Depot had a lot of grits I just got the coarsest since I was starting by hand and it was super slow (I actually cut the belts and double-sided taped them to a glass plate haha)


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## jessf (Dec 17, 2017)

For thining i wouldt start with anythting lower than 80 unless you want to be chasing deep scratches. 36 and 50 are for serious stock removal. 80 or 100 and up is where you should consider starting for thinning. It will produce more heat but with a slower 3x18 belt sander heat builds up more gradually so its easier to manage.


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## aboynamedsuita (Dec 17, 2017)

jessf said:


> For thining i wouldt start with anythting lower than 80 unless you want to be chasing deep scratches. 36 and 50 are for serious stock removal. 80 or 100 and up is where you should consider starting for thinning. It will produce more heat but with a slower 3x18 belt sander heat builds up more gradually so its easier to manage.



Point noted, I'll be starting around 100 or so, probably work outside today since it's only like -4°c and the belt sander says to take the Collection bag off if sanding metal, I may hook up the shop vac to the port if I'm working inside though


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## Dave Martell (Dec 17, 2017)

Grind lengthwise on that cleaver. You have less of a chance to create over grinds + the finish will come out much finer and nicer looking. 

I'd go so far as to clamp wood on both sides to make a guide/stop. This would allow you to get a nice crisp looking transition and select your bevel height.

Sharpen the cleaver first and then grind down until the edge is almost gone and even along the length.

Use finer and finer grits and maybe even buy a 3x18 Scothbrite belt to finish.


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## aboynamedsuita (Dec 22, 2017)

Dave Martell said:


> Grind lengthwise on that cleaver. You have less of a chance to create over grinds + the finish will come out much finer and nicer looking.
> 
> I'd go so far as to clamp wood on both sides to make a guide/stop. This would allow you to get a nice crisp looking transition and select your bevel height.
> 
> ...



Thanks for the tips Dave, et al.

I was off the forums when this was posted and trying to work with the small platen on the inverted handheld sander with wasn't as easy as I had thought I have a new level of respect for those who make their livelihood at this and also for the serious hobbyists.

You can all laugh at this setup lol




Here it is after I gave up hand sanding, I'm raising the shinogi from about 12mm to 40mm. I discovered that gorilla tape at Home Depot is like an electrical/duct tape hybrid and useful. 



I was able to get some decent removal with the grinder doing quick passes from heel to tip (several seconds to complete), but have since switched to using my sigma power 120 stone like the takeda handheld whetstone I was surprised how warm some spots got at the lowest speed, it wasn't too hot to hold barehanded and there's no discolouration but if you were to touch at the right spot towards the shinogi it'd be uncomfortable for a brief moment. Hopefully I didn't fk it up lol


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## Dave Martell (Dec 22, 2017)

Looks like fun T!


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## jessf (Dec 23, 2017)

Sounds like you were doing it right. I keep one gloved hand and one bare hand to feel for heat. I basically lay the knife down rub back and forth then dunk in water, shake off, then repeat. The sander seem to be able to handle some water without issue but i wouldnt go nuts, make sure you shake the water off the blade after cooling.



aboynamedsuita said:


> Thanks for the tips Dave, et al.
> 
> I was off the forums when this was posted and trying to work with the small platen on the inverted handheld sander with wasn't as easy as I had thought I have a new level of respect for those who make their livelihood at this and also for the serious hobbyists.
> 
> ...


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