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Old 06-10-2021, 11:23 AM
Ed Caffrey's Avatar
Ed Caffrey Ed Caffrey is offline
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2 x 72" Grinders.... A rehash

OK.... I know most of you have heard/read my feelings on 2x72" grinders, but recently I am seeing, and receiving emails with people who claim to be "serious" knifemakers, asking me for my advice on some el-cheapo grinder.... typically something from Amazon or Harbor Freight..... then when I try to explain that they are simply throwing money away, and to save their pennies for a "Top End" grinder...... I get a bunch of guff.
So for the sake of some of those folks possibly finding this thread via an internet search, or me being able to copy/paste it, here are some thoughts on 2 x 72" grinders.

*** DO NOT TRUST AND INTERNET SEARCH WHEN SEEKING ADVICE ON A GRINDERS!**** I just did it....and the first thing that pops up, rates the Grizzly 2 x 72" as "The Best grinder" NOTHING could be further from the truth. Get on the net and look up established knifemakers, and get their input! If you haven't figured it out...these are the people who have the experience, and know what they are talking about....period!


1. If you are anything other than a dabbling hobbyist, and you think you need a "grinder"....then you need a quality 2 x 72" grinder.
**Build or Buy?** First of all, far too many overestimate their ability/skills when it comes to fabricating a 2 x 72" grinder... thinking they are going to save a ton of money by building their own. Sadly, with the exception of a few who are experienced/gifted/talented fabricators, it usually ends up costing as much or more, for a machine that runs poorly and doesn't do what the individual wants/needs. For the majority of people, they will be far ahead in terms of money, time, and effort, to purchase a grinder instead of building one.

2. Yes, they can be spendy, but you will get what you pay for, especially a 2 x 72" grinder. That is...provided you do your homework, and NOT buy from any of the "Johnny come lately" outfits.

3. There are a TON of "new guys" building and selling 2 x 72" grinders.... BEWARE! Many of them are only trying to capitalize on the current popularity of knifemaking, and building the cheapest machine they can, then selling it for what seems like a screaming deal price.... but when you need support, service, or parts.....they won't be there. If the price seems too good to be true....it very likely is. Scrutinize EVERYTHING about any grinder you are interested in buying.... take the time to call (do NOT email or PM the seller) and ask questions. If the seller can't or won't answer your questions, then it's best to look else where. Talking on the phone will also give you an idea of the type of person/company you are dealing with. Yes, it might be old fashioned, but I trust my gut instincts, and can usually tell from a single phone conversation if I can trust and/or like an individual or company. The "wheels" used on the machine can tell you much. Are they actual rubber or urethane wheels? Do any wheels with bearings have shielded or sealed bearings? Do the wheels on the platen assembly have smooth or grooved wheels (grooved wheels can be very dangerous, so look for either smooth aluminum or rubber/urethane wheels on platen assemblies) I have seen some really STUPID things such as caster wheels, open bearings, and even skateboard wheels being used on grinders that are for sale to the public.... any of those are just accidents waiting to happen, and if you buy something like that.... I simply have not pity for you.

4. What brand should you look for? I have my favored brands..... those being KMG/Beaumont Metal works, Bader, Burr-King, or any other brand that has been around, and proven to withstand the test of time.

5. The heavier the better! Many tout "light weight".... or "light weight and strong". Don't believe it! When it comes to grinders, lighter equates to increased vibration, chatter, and often times LESS durability than machines that are "over built" with steel construction. I am not even a real fan of aluminum tooling arms for most grinders...with the exception of those such as the KMG TX, which thoughtfully has "tabs" that place pressure on the tooling arm, versus the end of a bolt that digs into an aluminum tooling arm.

6. Speaking of tooling arms.... SIZE MATTERS! Specifically, I recommend only those machines that use 1 1/2" tooling arms. Why? because that is "the standard", and most all accessories offered are designed for machines that use 1 1/2" tooling arms.

7. Steer clear of machines that tout/use Aluminum, or those that have all kinds of "eye candy" cutouts in the frame/body of the machine..... both lead to increased vibration, chatter, and are simply not as durable.

8. Variable or single speed? Plain and simply....VARIABLE... and more specific, a 220V/3 phase motor, with a VFD (variable frequency drive) speed controller. Don't skimp on the VFD/Controller! I know some folks go with the cheapest controller they can find....but just buy a KBAC brand, and you will be worry free. I've used the KBAC VFDs every since they became available to the public....and there is not a more simple, durable, or longer lasting VFD on the market.

9. How much should you pay for a grinder? That depends on your needs/desires, but I'd say that if you find a Variable speed package 2 x 72" grinder, for less than $2K, then be suspicious.

Some are now saying... "BUT! I can't afford that!" Fact is, IF you are trying to make knives at any level above a dabbling hobbyist.... you can't afford not to! The machine will be the center of your shop, and you will find that it will be used every day you are in the shop, whether you are knifemaking that day or not.

10. What size motor? I personally use 3HP Leeson TEFC motors and KBAC 29D controllers on my grinders (I have 3 grinders). Remember this.... you WILL "grow into" a larger motor....but if you start out with small (as in 1hp), you have no room to grow...beyond buying an larger HP motor..... so that being said... I recommend at least a 2hp motor. NOW... out of necessity, you may have to go smaller if you don't have the power (220 Volt) to run a grinder. In that case, I would suggest to seriously consider installing, or having a 220V circuit installed, and go with the 2hp motor.

Finally..... I'm just gona come out an say it. I recommend Beaumont Metal Works, and the KMG grinders. I have worked on just about every brand/type of grinder out there that can used for knifemaking, and keep coming back to the KMG machines. They are simple and thoughtfully designed, built like tanks, and the customer service far surpasses any other I have experienced. KMG states "Industrial Belt Grinders and Machinery" and they mean it! I can't think of any other brand of grinder that makes that statement.. and demonstrates it in their products like Beaumont does.

VFDs.... KBAC in the proper model to match the HP motor you choose. I buy my KBAC VFDs here:https://www.electricmotorwholesale.c...rch/?term=kbac They range in models, and you MUST have the correct model for whatever HP motor you intend to control.

I'm sure there are tons of other opinions out there, and that's OK. Everybody has a right to their opinion....but I am speaking from 30+ years of experience using 2 x 72" grinders.

Feel free to ask questions....because there is no way I could cover all possible questions in one post.... GO!


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Last edited by Ed Caffrey; 06-12-2021 at 08:18 AM.
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