Cheap Diamond Sharpening Stones - Any Good? 

I use cheap diamond stones *not* to sharpen tools but to flatten and restore the surface of my *wet stones.* They work great.

I've been using my cheap plastic backed diamond rod for 2 years. It's all I use. It puts a razor sharp edge on everything fast.

As a general rule I recomend DMT products. I prefer the steel based plates, mono diamonds and BALLISTOL diluted with water for lubing. Then you wash with clean water and dry, allow the stones to COMPLETELY DRY BEFORE STORAGE. You do not want moisture or ANY solvent that will displace or damage nickel over time to remain trapped near or in any diamond plate for obvious reasons. I also use Spyderco ceramics with great success. 40 years of hand sharpening and honing. The BEST skill I ever learned from my grandfather.

hi mitch, as a professional cabinet maker i will admit that i use the cheap set for preparation of my blades and then use a dmt fine/ultrafine for final hone. they do a perfect job and are a fraction of the price. by the time i have stropped the edge i am shaving with the blades. i freehand my sharpening and take a max of a minute to carry out a full sharpening with a dull blade as per my video here on youtube. i think one of the popular misconceptions with tools are that cheap is nasty and expensive is good. i buy cheap chisels as the steel in them is just as good as the fancy very expensive chisels. after all a chisel is a chisel is a chisel lol

I had a cheap set of stones, I found the diamonds wore off very fast. However I replaced them with an $80 Australia 8 inch diamond stone that has worked a treat for years now

I purchased same set of three stones and I must say I like them. I have done some serious hours long grinding and the diamonds are holding well.

I use them purchased from Harbor Freight over here for $9.95 a 2x6- 300.400,600 and 800 grit and their own non skid block housing and they work just fine for me !

I have a Harbor Freight diamond sharpening block that has worked quite well for about five years. It's my go to for flattening chisel and plane blade backs. With 200, 400, 600, and 800 grit faces it rips through pitted tool steel with ease. I've used it to sharpen brazed tungsten carbide metal lathe tools. I like that it withstands an abusive environment. Requiring only water as a lubricant is attractive but the grit and scarf left behind in the stone rust unless it's washed and dried almost immediately. I give it a ten for price, a nine for utility, and a six for sharpening. The holes in the matrix are a problem for use with smaller edged tools.

Hi Mitch, I also have some of the cheap diamond stones (they are available everywhere it seems at the minute) I personally couldn't get used to them for the finer finishing but I do like them in certain situations such as removing chipped edges, and also putting an edge onto garden tools such as shears, brush slashers and lawn edges. I have found alot of the cheaper stones can vary vastly in quality aswell, it's a bit of a lottery. Nice film by the way, I am now a subscriber. N.

The cheaper ones soon come apart from the plastic base after a bit of flexing and moisture but they're usable for freehand honing in certain applications instead of the credit card sized diamond plates. It's the flexibility that makes them useless for larger chisels and plane blades and the sharpness of cut seems to wear out pretty quick...

Thank you. My favorite teacher in the world, is Dr Donald Kagan, who teaches Greek History at Yale. One of the things I love about him is that he is so good about documenting his work, that even from the lessons he teaches, you can find yourself disagreeing with him because he so fairly presents the material, that you really can make up your own mind. Likewise, I think this video was great. It clearly showed what they do, what the benefits and the costs are. For me, I think this helped me decide that I am willing to spend a little more on the more expensive stones, but I could never have decided that without this video which gives the less expensive stones a fair review, and shows them at work in reasonable conditions. Thank you for making this video and helping people make their own informed choices based on real examples. I really appreciate it.

Yours are brand new. I inherited a similar set from my father. If you're not after precision or flatness, then fine... The set is blue/red/yellow (the coarseness of the grain not writen anywere by the way, so you have to guess...), some years old and didn't age well (an understatement). Meaning: the plastic plate (on all three of them) is bend like a bow and the diamond plates (sheets rather, they are so thin) are half "de-glued" and - no surprise - bend as well... they are still abrasive though... I still have two DMT credit card ones I bought years before my dad passed away and they are in way better shape... pun intended.

I've used the Trend 1,000 / 300 extensively and am very pleased . $150 US dollars. I free hand sharpen both chisels and plane blades. The 1,000 is used to establish a secondary bevel and the 300 side is used to flatten the 16,000 Shapton that I use for the tertiary bevel for both planes and chisels. Using this method I get shavings that are 0.0005 of an inch and leave a polished finish on the wood.

I went to a local granite countertop shop and came away with a bunch of free scraps that work as excellent backing for these or for wet-dry sandpaper. For polishing, I have been using the same block of hard maple and compound for about 30 years. Still working great!

this was so sensible and puts things in perspective. Thanks for sharing...subscribed!

I spent a lot of time in a cabinet makers work shop while growing up. there were generally about 5 craftsmen working there at any one time. They taught me to sharpen chisels on oil stones I now use diamond stones. I find the mid range stones much cheaper I honed a new chisel on a cheap diamond stone recently. Once I'd finished I threw the stone away it was shot. The stone cost me £8 for one sharpen! If you don't want to spend £30 for a decent one buy an oil stone.

I just at the beginning. I hope to start out soon. I don't have a belt grinder and space is limited. So I think what I have will work for now. I can't wait to get started. Cheers to you mate.

Very interesting, Mitch. If you're not a professional woodworker - or aspiring to be one - I wonder how low a price you can go before you'd quickly notice how your diamond stone is doing you a disservice; flexing, actually wearing out, etc. For sharpening, or grinding really, I have two DMT Duo Sharps, one with Extra Coarse and Coarse, the other Fine and Extra Fine. I bought these instead of the Paul Sellers' recommended brand, Eze Lap, because they were cheaper. Trying to make myself feel better at ignoring Paul, at the time I swallowed DMT's pitch that their monocrystalline diamonds are better than polycrystalline ones, which EZE Lap uses. However, now I no longer think this is true. Both types are good, in different circumstances. Next time around, I might well go with Eze Lap. Fortunately, DMT makes good quality stuff, and my stones have been standing up to the type of abuse only an ignorant rookie could dish out. It's been about two years of hard use, but my stones are still perfectly flat and cut very well. Here's a somewhat interesting story. When I was doing research on DMT stones, I read the reviews at Amazon.com, and one reviewer said that the DuoSharp I intended to buy was worth five stars - but only for flattening water stones. As sharpening stones for knives and plane irons, he gave it about one or two stars. I felt that the review somehow insulted me (and of course, my budget), so I bought the DMT stones immediately. Oh, the young and rash. But, as I got deeper into woodworking, I learned more about what "sharp" really means, and I got to hearing more about getting the blades polished right up to the edges. One way is the way you describe it Mitch, diamond stones followed by MDF and metal polish (or with Paul Sellers, green honing compound), while the other is with water stones. After months of thinking and picking change under the sofa cushions, I decided to bite the bullet and bought four Shapton Professional water stones, straight from Japan. These were the 2k, 5k, 8k and 12k stones. I learned two things. 1) Diamond stones do a great job of grinding your desired shape. But to if you want to really want sharp, you need water stones for honing. 2) Though not the best to do so, the DMT stones do work well in flattening the Shaptons. That reviewer in Amazon.com was completely right. *sigh* I don't use microbevels, so the Shapton 12k gives me a big rectangle of mirror-like surface to the very edge. It's sweet to look at, and even sweeter to cut with. This, together with some hard lessons in setting up a hand plane, has enabled me to completely vanquish tear-out, in ash no less, which is a surprising little bitch. But, back to cheap diamond plates. I wonder whether I could have as easily added water stones to my arsenal if I had gone the economic route. Certainly I wouldn't trust my Shaptons to a stone that flexes, or won't stay in one piece. Perhaps one day a brave, intrepid soul would do a comprehensive video on this, showing long-term results, and save the budget of woodworkers everywhere. Anyway, good job on the vid, Mitch!

Great information on stones allays a mystery on what is the best so many on the market at different prices. A useful video for the hobbyist. Shaun.

Yes, I have had a set for years. Separated from the plastic backing soon after buying & I mounted them on 5/16 oak. Great for a quick edge, not a fine/scary edge.

I have similar cheap or inexpensive 'stones' purchased from Harbor Freight and I've had fairly good results with mine. I wouldn't use them as the be-all/end-all for maintaining my tools but they are sufficient for getting through the day or job and still have viable, working tools at the end. I was rather disappointed with the inadequate plastic backing but a few moments of salvage work and they were mounted on some beefier hardwood and dilemma has been reduced to a memory. I would recommend them (the cheap stones) as a matter of resolving a necessity. The price was far cheaper, here in the States, than what was demonstrated in the video but that could be just a Locale issue, nothing more. I've had mine for about a year now and I must willingly say I am quite satisfied. I've been woodworking for over 50 years (yes, we did woodworking back then...) and I know what a bargain is when comes to maintaining my livelihood! Enjoyed the video...thanks for sharing!!!

I had cutting compound for use on buffing car clearcoat. It achieves a great result. Stick some leather to a piece of timber and about 30 strokes later, a mirror finish.

Will they sharpen? Absolutely without a doubt. And for an infrequent user for a very long time. But for someone who sharpens on a daily basis (butcher, wood worker etc) you will get about 5 years out of them at best. The key difference between a DMT set vs say you HF special is the type of diamonds used and more importantly the type of adhesive used to adhere the diamond to the plate. DMT uses a nickel plating process to adhere a mono (structure?) type diamond that doesn’t break down as a diamond with many outcroppings would. Both much more expensive to manufacture.

Thanks! Great video. I recently bought a cheap Harbor Freight (that's a low end tool store in the U.S. if you aren't familiar) sharpening set similar to yours for $8 US Dollars if I remember right. I went from no sharpening system at all to having this Harbor Freight set, so my cheap chisels were greatly improved. I had wondered how that would compare to more expensive stones, so it's interesting to see your results!

Really no need for diamond plates for chisels - the good old Norton India /fine and coarse/ works superb in this role if they are followed by a soft or hard arkansas. Very useful video - thanks and have a nice day.

I use mine on top of a piece of granite and they seem to be fine. I also use a leather pad to finish off the edge. If i had access to the more expensive ones I would invest the money.

I've had some of these cheap diamond stones and they do a fine job to start, but they don't last. They are made with poly-crystaline cultured diamonds which fracture quickly and then are worn away. My 3 plates, "coarse, medium, and fine" are now indistinguishable from each other after trying to restore a couple of old knives. So I'm saving up for some quality mono-crystaline plates which I expect to last much much longer - 'till then, back to my wet stones!

Great comparison! Thanks Mitch. I recently started using polishing compound to touch up edges when I work. Its inexpensive to setup and a quick way to keep an edge sharp.

New to sharping my chisels and plane blade, I used coarse and fine wet and dry sandpapers with a strop finish for a lovely result, must say a bit extra work tho

For preperation of a sharp edge, a cheap stone could be an echonomic solution. However the sharp edge itself is not enough. We also need flat chesel and iron surfaces too. So it would be a better comparission. Either way it is a nice video.

I use the Harbor Freight 200/300/400/600 diamond (looks just like what you have there in a block) to do my rough sharpening and a 1000/4000 combo water stone (also Norton) for finish and touch up. I am pretty happy with the shavings off my smoothing planes and chisels. I may add that mdf strop though... hmmm

Hi Mitch. First, this is an excellent idea for a video and your presentation/ observations were great. I have used several methods for sharpening my tools including the exact same set of of cheaper diamond stones. My own observations were that yes they can put a workable edge onto chisels and a scrub plane blade. Bottom line is " you get exactly what you paid for " and they are absolutely fine for a wood worker to use in their shop especially if a wood worker is just getting started. Diamond Plates are obscenely over priced in my opinion and I have found an excellent compromise between cost and the excellent end results I can achieve with my own tools. I won't get into the weeds on this but I use the "Scarey Sharp" method utilizing Float Glass and many grades of automotive sand paper. There are several RU-vid videos out there that clearly demonstrate the set up and process and if anyone wants to consider this alternative sharpening, I have no reservations recommending it. I have achieved results that rival any type of stone at a fraction of the cost. Maybe you can consider putting a comparison video together using the diamond and sand paper methods to the test. Cheers Mitch. Derek

Thanks for putting this up. Help me decide which to buy.

Thanks for confirming that what I suspected for my amateur efforts was adequate

Good video Mitch. I use a Worksharp power sharpener for my chisels and plane irons. It works great I too have a Harbor Freight cheap diamond hones that I can't complain about. I think I paid $30 for the whole set and I've had them for years. $75 for each of the premium stones is a tough pill to swallow, especially if you purchase 4. $30 vs $300 is an easy decision.

I bought this set at harbor freight. It made quick work of a badly chipped and incorrectly shaped plane cutter. It took about an hour to go through the different grades to set the angle and get rid of the chip. I then used the scary sharp method up to 5000 grit.

what a brill vid thank you am just starting with wood working you can blow your mind with all the info on sharpening chisels so this very helpful have just got a multi sharp for doing chisels and plain but wish i had seen this befor getting it as think this would have been cheaper and give a better end result Thank You

Nice demo! Stones can also do a fine job for a lot less money than the diamond hones.

useful video, succinctly presented. thanks

I did a video on this and these were my favorite. The stand on mine wasn't great so i just clamped down. Good video.

I use them and they work great

I used a heat gun to separate the diamond plate from the plastic then used epoxy to stick it to a tile.

gonna try that mdf tip,I buy set of those cheap stones once a year and finish with 1200 grit wet and dry, the mdf seems less hassle if I get some honing paste thanks for the tip, thanks for your advice regarding my stanley 45,I managed to find some 9mm stainless rod which is less than 0.5 mm off an airtight fit so I think that should be fine hopefully

I got a cheap set a while back. After a few sharpenings it stopped cutting. The diamond wore away almost immediately. I threw them away and I bought two combination water stones for fifty bucks a piece. Had them for two years.

Nice demo Mitch. The question is how well they last over time.

Very helpful going to get them cheap ones for my carving knifes. Thank you.

Great comparison. Thanks for posting the video for us hobbyist from Fayetteville, Ga usa..

I made a whole box for a set of these things with an insert on the lid to hold them and keep them flat. I've used them for a while now, and last if you use an oil (NOT WD40) and keep them clean. If they come apart, glue them back with some silicone and they'll hold for a while. I've found the medium and coarse grits aren't really useful unless you're resetting the bevel, but I get a useable edge.

I use a 120 grit and a 400 grit diamond stone and while they do work just fine on tools steel or carbide tools they are not that useful on high carbon steels (found on laminated western tools and Japanese tools) as the diamonds don't cut as well as Silicon carbide or Aluminium oxide. This can cause tensions within the cutting edge reducing its lifetime. The plates I'm using are actually professional grade ones and about 3 years old now :) I started noticing this after about a year of use so while they are virtually useless for most of my tools I can still use them on 2 of my planes and for flattening my sharpening stones :) If I wanted to buy one again I would go for a medium priced stone like yours or an Atoma especially since they have grooves between the diamond "pads" which allows for the metal chips to be channeled off. On the plates I use the diamonds are evenly scattered over the surface which is not good at all because the material that is ground off clogs the plate and you need to rinse it very often to get it to cut again :( My conclusion is that neither are suitable for my use :D the cheap ones disintegrate too quickly and the expensive ones don't hold up long enough and have too many design flaws....

Beautiful video, Mitch. My Stechbeitel I've always sharpened with Japanese water grindstones and polished. For the planer knives I have now Diamond Sharpening Stones (medium, fine, superfine) concerned, like Paul Sellers.

I bought the lower priced diamond hones from harbor freight tools in 1996. they still give a decent edge on chisels. Altho it takes more time to sharpen a tool than when they were new.

I use the Harbor Freight version (under $10.00 US) and glue them down with some CA. That keeps them good and flat and keeps them in place.

The worksharp 3000 is the best thing I've ever purchased for my shop. I'd go that route.

Nicely done! I have the same three cheap stones and just recently sharpened my 6 inch jointer knives. They did require quite a bit of elbow grease but did produce a fairly good edge, however, I'm glad you mentioned the honing paste as I lacked that nicely polished look. Where might I get some of the paste as I live in Ontario, Canada and haven't seen any as of yet? Again well done!

I have recently purchased and used similar diamond sharpeners and you hit the nail on the head with the flex issue plastic backs . All around good advise , thanks.

I was looking at cheap sharpening stones the other day and was wondering if they would be any good for me, thank you for letting me know, I'm off to get some this week.

The biggest problem with cheap diamond stones and files is that they loose the diamonds pretty fast. Better quality stones last many times longer and are therefore cheaper to use in long run.

briliant old chap, simply remarkable, mdf and paste it is!

Thanks Mitch for the informative video. Great job!

Thanks I have those exact cheap ones the actually work ok. thanks for the video much appreciated.

thanks for the video it really helped because I have 16 chisels to sharpen and now know what to do

Do a few other tests. Look at flatness of the stone might be a good one. And I'd be surprised if the cheaper stone lasts even a 10th of the use of the better stone. I've had a Trend 300/1000 grit for 12 years.

Hey Mitch. I bought a 3 pc set from Harbor Freight. One not on that set is the "fine" is 360 grit. I use a black granite tile 12x12 as my base. After the fine pass I use either 500 grit and sometimes 1000 grit wet/dry sand paper. Then strop them. Oh, none of my media are fixed in place. The sandpaper I stretch with my free hand.

You saved me lots of money. Thank you.

Hi, I have a mixture of diamond stones all of varying grade and price,the cheapies are great for rough work shears etc and I have sharpened chisels on them ,for final finish I use my spider stones which are very expensive but worth every penny,I still use my old norton/india/others when I'm being sentimental,cheers malc

Great job. Well done. Thanks for the comparison of diamond plate options.

It's not the ideal way to sharpen, but it's what I use... a large hone, bench and guides can't be EDC items, but a few 4" diomond hones and a polished ceramic tile rip fits easily in my pocket. I can sharpen and shave with an old spoon if I want, any time and anywhere.

They are good for sharpening things like garden tools etc and restoring primary bevel on chisels. Not much good for getting them "scary" sharp

Stuck some 3mm plywood on it. Works good for $10.

This was one of the better pieces of advice I have seen for taking care of my chisels and gouges. Do you have the video for tuning the Plow Plane yet?

I use knives every day in prosthetics . The cheap diamonds are great, I hit em several times a day.

I had a cheap set, looked very similar to yours. Was on special and I think I paid something ridiculous like NZD $6. The plastic backing boards fell off in no time flat, and I didn't like how they felt. The seemed kind of rough and uneven. I ended up throwing them out and now use sandpaper. I like your suggestion of honing paste & MDF - I must try that.

They do everything I need them to do. Unless you plan on castrading a fly, I think they are fine. They're all I use for my knives, and my knives are plenty sharp. The only thing is, my stones have a 2 inch thick plastic backing, so they do not flex. (that's a good thing.)

i find they're ok if you need to refurbish an edge and take a lot of metal off. otherwise i use 'scary sharpening' and finish by stropping

great tip for me (beginner) thank you

I use them on occasion for my chisels, or resufacing my regular stones.....they are cheap and I have yet to replace them...they are not wide enough for my plane irons, but for chisels, along with a strop...seems to be fine....the are a little flexy and need reinforcement.

The HF diamond sharpeners are great. I use them for all my rough work such as nicked chisels, profiling old knives, and axes. They are still good after many years, and I use the heck out of them. I do have a better quality solid metal one for my finer work. You can use pressure sensitive adhesive sand paper on the back of them so each does double duty.

Great video; well presented and very useful. I just purchased a Trend honing guide for my chisels and plane irons, and Trend say that I should use diamond honing stones with it. Hence, I am wondering what price range of stone I should invest in. I do a few hours woodwork every few days so not a heavy user. Helpful advice in the video and may go for the cheaper version to start with. Love the tip on using MDF with stropping cream! I've always had trouble getting a straight blade edge with the standard honing guide with a single, small wheel, which is why I have bought the Trend one with a two inch wheel, which works a treat.

not sure how quality is important in tools, but i was using diamond initially for kitchen knives. When new, it did great, but after a while, the fine grit (600g) started to wear out . i remember i would get a really nice bite with the courser grits nut when i reach the 600g, it completely undid my hard work. i suspect it could have been deformed over a period of extensive use;

Water on diamond whetstone can destroy the whetstone. Try using lap oil, a good lapping oil would be mineral oil with vitamin E. Your technique needs work. When using the cheap stone try angling the edge to avoid chipping the edge or the stone. Using rubbing compound and mdf should be done by pulling the edge only to avoid gouging. Maybe try stropping with your compounds and only use the same grit compound on each strop or mdf. I have used the cheap stone with grit 200, 300, 400, 600. The stones that you were using were most likely Blue 180, Yellow 260, Red 360.

Great demonstration. Thanks.

Very very interesting! I did not know about the MDF being a good finisher of edges?? so the cheap diamond sharpeners are alright for occaisional use, thank you very much

Very helpful video. I've just got some of the cheap ones and will give them a try.

You don't have to push so hard. Moving them back and forth is enough. Otherwise you will eventually break of the diamonds

Hey mitch, good demo/compare.me personally like the water stones. I made a little set up/station for them when i do use them. Ive ised the cheap harbor freight plates which look identical to thoe cheap ones u had. I also bought a set from rockler. Tbh i didnt care for either of them. i prefer the water stones. And i never knew that about mdf!. Thanks for sharing these little videos. I really appreciate them and find them helpful. "Learn something new everyday"

For me the bigges disadvantage of the plastic-backed ones is that they have holes.

Iv alway preferred wet stone as long as you keep the stone flat nothing beats it

Had some cheap diamond but threw them away. I am a fan of the Norton India stone and leather.... Together they produce a wonderful edge. Only 2 weeks for toolmake15!

I have a set that look like yours they came from Harbor Freight the problem they have is that they are curved from front to back and from side to side. I can't use them on plane blades or chisels, when I remember that I have them I use them to sharpen our machete.

I have the HF ones as well. They work well on a flat surface. I also picked up one of their $10 1/4 sheet sanders that I put in a jig with a hard base on it, with some spray tack glue on it. This allows me to change grits fast, and get in the neighborhood for the final honing and stropping. Great review.

I had a try with a set of these. Also one of those cube things with a different grit on each face. I found their flexibility to be an issue and in a short time they came away from their plastic backing and the abrasive soon wore away. Never used a really good quality diamond stone but this kind of put me off.....its not the diamonds, but what holds the diamonds to the plate I worried about.......So I bought a good set of waterstones. :o)

The cheap ones come unglued after a use or two, and im also sure they wear out really fast, not so good IMO, also for the stropping, theres a much easier way! get a polishing wheel on your grinder and block of polish, go to town on the bevel and in about 5 seconds it will be so sharp you wont believe it, so much easier than all the other messing around

Did I see wrong or was the cheap version allready bending while sharpening? I have rather expensive diamond stones and also leather strop for polishing (I use the polishing paste from tormek). To me these stones are the best solution. They are flat and they stay flat. Just a bit wd40 and I'm good to go. I feel that honing guides break more easily or the wheels wear much faster on diamond stones then on other stones. So i learned free hand sharpening. Anyway. The result -sharp tool- is the only thing that counts. Not the method or tool was used... or price. And this video shows that both results are pretty much the same. But in my opinion it also shows the quality difference. (Bending).

The cheap ones r perfect for site work cos when they get nicked ( and they will) it doesn’t hurt so much

Thanks Mitch. I need to revamp my sharpening system. I use Norton water stones now but honestly I hate the mess and don't have a proper stone to flatten them.

Thanks for sharing. Think I have some issues with my sharpening technique. But probably just need some more practice :-)

# One draw back with the (cheaper) plastic block 'stones' is the larger 'holes' between sharpener that make consistent strokes more difficult on smaller section tools - e.g. that narrow chisel

only the super fine is any use. Hard to keep the stone stationary. A finer stone is still recommended though. Personal experience from working at an abattoir

we use 'em glued or double taped to wood paddles or bats. they work o.k.

I'm just looking to keep a keen edge on a few stainless steel kitchen knives. So the el cheapos should do well enough for that. Thank you. To the point without any b.s.