PRECISION GROUND TOOLROOM STONES

I describe/show where and how to use precision ground flat stones. Why these are an absolute must for working with high precision tooling. What makes them work and how to make your own your own set.
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Two of the papers I mentioned
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www.sciencedirect.com/science/...

[@wallacesaan]

Robin: thank you SO much for this fantastic video! I immediately bought a couple pairs of stones and ground them (one set for myself and one set for my son). They are amazing. A quick tip for others when grinding them ... Rather than making the nifty hold-downs like you have, I simply used a couple of toolmaker clamps lying flat on the mag chuck and lightly snugged up on the stone, one at each end. Worked great.

[@ROBRENZ]

I like the toolmaker clamp idea! I have had the hold-downs forever so they were my first pick but I love the toolmaker clamp idea! Thanks for watching and commenting!

[@James-fs4rn]

wallacesaan thanks for the great idea!

[@tobyw9573]

Would a smoother mating surface on tools and tool holders work to reduce tool chatter? Tightening forces might distort mating surfaces into enough contact to render finish moot. Chatter might make a good video. Or maybe optimizing chatter in lesser quality machinery. I have headphones with great response and Abom’s big lathes and work have resonance at near subsonic, for instance as does his camera.

[@DracoOmnia]

would you mind making more and selling them? Some of us don't own surface grinders..

[@johnlampros7038]

I was taught differently, You would rub the stones together to keep them flat and only coarse to coarse and fine to fine . Fine to coarse will contaminate your fine stone with coarse particles. They should be kept separately and everything cleaned before changing stone to minimize cross contamination. The stones wear and can wear unevenly and is is vital to keep them dead flat. and should be checked often.

[@techno_mesh]

By comparison, the stuff you just taught in the video makes me feel as somebody opened a door in my bedroom disclosing something I didn't know existed, but what is more daunting, I didn't know the friggin door existed!!!!!!! Thanks!

[@ROBRENZ]

Thanks and thanks for watching and commenting! I like that analogy.

[@RaivoltG]

That's a good one!

[@kreglamirand2637]

Man... this is just incredible. When I first got into this hobby I could barely comprehend dividing an inch by a thousand. Now I'm learning from a master about super pricey stones, optical flats and millionths of an inch.

[@oxtoolco]

Finally! You've been threatening to do this video for ages. I so glad you found the time to produce it. I think Norton will see a spike in sales for the combination bench stones. Excellent video! Talk to you soon. ATB, Tom

[@Engineerd3d]

Where is the shaper video Tom? I have been digesting all of your videos over and over again. I have need for shaper videos in my diet. :)

[@davidberndt6275]

One could say 'Tasty'

[@ROBRENZ]

Thanks Tom, as you are well aware sometimes it can be tough to make time for doing videos. ATB, Robin

[@Engineerd3d]

Absolutely! I did not mean to sound like a demanding arse to Tom. Love the videos from both of you guys. This stone video has been put in my to do list now, right after reassemble and test my surface grinder.

[@TechGorilla1987]

I'm watching this video for what is probably my 5th time and it's 2020 now. Robin, you and ToT have some of the best content out there.

[@ROBRENZ]

Thanks, that's quite a compliment.

[@TechGorilla1987]

@@ROBRENZ I truly mean it. I really wish you could put out more content. You have a balance of perfectionism (usually a psychological deficit) and f*ck it, lets roll with it fortitude that I admire greatly. What I wouldn't give to be your apprentice as I have said several times in comments. I'd learn more cleaning the ways of your lathe than I would have through a tech school education.

[@Ihorecek195]

@@TechGorilla1987 Im watching for 5th time aswell, i actualy bought BPH 300 surface grinder just because i watched Robin do so much things with it. I think that Robins videos are very saturated with knowledge that isnt easily found anywhere else. Its really amazing to see that every video from Robin is just so different and full of useful information. I think that Robin is one of most influential people for me, im trying my best to do everything as perfect as i can, thanks to Robin. Thank you Rob, its been pleasure to watch and learn from your videos!

[@ShadonHKW]

I have a (single) diamond ground stone that gives me occasional problems with stray scratches, I am constantly at the sink cleaning it, this clears up a lot of the mystery, thank you for this, always enjoy you videos.

[@ROBRENZ]

Thanks Stan, I enjoy your videos also but I have bee so busy I have not had time to watch and comment like I would like to. Hope to make the bash next year. ATB, Robin

[@AJMansfield1]

9:40 lol, no you were right the first time, it's a 1-6-6 block. A 1-1-6 would be a long rectangular bar, that one's a wide plate. Love the video and the explanation for how precision flatstones work; even though I'd heard of them, it's not something I'd really known anything about before this. 13:00 ok wow I was just thinking "would be really nice to see how you'd use these to actually remove a visible burr or surface damage" then right as I'm thinking it, the mad lad _he does it!_

[@markwatson9816]

Wow. Yet another master class at the feet of Professor Robin. On a humorous note: This is the first time I've been lectured for 35minutes of the virtues of getting stoned and it's completely legal!!!

[@handsofrhythm3415]

Thank you Robin for taking the time to make this long format video. I know you prefer the short format of instgram but these larger chunks of detailed information are really appreciated by the rest of us. Keep excelling in your craft.

[@bobeboph]

My only regret is that I have but one like to give this video. Thank you for sharing your amazing breadth and depth of knowledge with us!

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@vpitool]

Robin. could please you do a video on mounting and dressing diamond wheels on the surface grinder?. This seems to be one of the things we struggle with most in the shop... Thanks for all the great videos!.

[@davidgoodell4298]

I have been a tool and die maker (mold maker) for 40+ years. I am learning all kinds of stuff. I feel a bit stupid now.... Thanks

[@Carknocker001]

Another fine seminar offered by Renzetti University! Thank you!

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@raystanczak4277]

I want a set of stones-and I’m not even a machinist! Always enjoy the high level expertise and knowledge that you bring. I’m not a machinist, but one of my earliest jobs (50 years ago) was as an inspector in a precision machine shop. The gauges that were required, and the education required to use them properly were all directed towards production of these beautiful (to me) finished pieces which started out as a dirty bar of steel on a pallet. I remember looking at my first granite table and wondering what the hell that little, thick table was for. It looked kind of...ridiculous. Turned out to be another amazing precision instrument. Thanks!

[@dip20000]

The stones where developed by Japanese engineers at Nikon precision, they used them on polishing ways of wafer processing equipment (electronic industry).

[@greglaroche1753]

Great video. Thanks ! Not the first time I’ve watched it, but each time I pick up new information.

[@markrobbins4700]

Im a moldmaking apprentice new to this trade , the information is awesome so informative !!!

[@Preso58]

The whole time I was watching this I was wondering how you were going to hold it down to the mag chuck. It seems there's always a way. Very informative and interesting stuff! Thanks.

[@bcbloc02]

Deliciously educational! I don't need any ultra flat stones to see the imperfections in my grinding though. lol

[@ROBRENZ]

Thanks Brian and thanks for stopping by. ATB, Robin

[@davidcolwill860]

Thanks for taking the time to do this.

[@ROBRENZ]

You are welcome

[@somebodyelse6673]

This is actually one of the very few "things you didn't know you needed" - that I actually need. Amazingly clear and direct presentation, as well. Please keep sharing the wisdom, you're shining a light on stuff that I don't think is taught anywhere.

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@danielwerger5641]

Robin, you blow me away with your content. Very, very cool and very, very useful. Thank you sir....!

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@moeszyslack4676]

Another great video Robin, thanks for putting it up. Your work and attention to detail is on another level. Always a pleasure seeing a true craftsman (or is it now artist?) work and share his knowledge and skill.

[@ROBRENZ]

Thanks for the kind words Moe and thanks for watching and commenting!

[@slausonm]

One of the best oxtool videos is when he urged his viewers to check out your videos. I love your teaching method and the quality of your work. Thanks for another great video.

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@keithkrueger1609]

we made a dozen sets at work. they work great. it was a great upgrade from standard stones.

[@dfailsthemost]

"No bite" is exactly what I need. I've done the math, and I need even contact on as much surface area as possible. Otherwise I'll end up scratching into my part. So, I need the bur to press into the stone as opposed to the aluminium oxide particles pressing into the stones.

[@emilgajewski1371]

As always more then entertainment. I've used stones in my work going way back but you brought it to a new level in procession. Thanks and keep them coming

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@wallbawden5511]

Rob the way you explain things is second to none i enjoy watching and re-watching your videos get more out of them each time thanks for doing them

[@wtechboy18]

as a software developer I'm never gonna be able to justify spending like $500 on a pair of abrasive stones, but damned if this kind of content doesn't make me wish I could take a couple machining classes.

[@ROBRENZ]

You should!

[@wtechboy18]

@@ROBRENZ I'd love to, but I gotta get my current computer egghead degree finished, and also knock down some debts and stuff before I go and take up what looks to be a fairly expensive hobby. Soon, hopefully.

[@ctrlz4439]

GCODE is code too... You may get in CNC machining. However I am not sure if making hobby a work is good idea.

[@dfailsthemost]

I did. And it's awesome.

[@StefanGotteswinter]

Thank you, I was waiting for that video! Absolutely enjoyed it, very good information. I already gave a surfaceground stone a try and I was very satisfied, but I will make a matched par just as you showed. Are you familiar with the Degussit synthetic ruby stones? Those are over here considered as "flat" and what most people doing mold/tool/grinder work are using for stoning without altering the surface.

[@ROBRENZ]

Thanks Stefan, I knew of the ruby stones but did not know they were that flat. They sure are expensive and I think the cutting action would be a little different than the PGFS

[@StefanGotteswinter]

I ran an indicator over both of my ruby benchstones at work, they are well below 1/100mm flat - The medium grot ones do not have any cutting action, they just burnish the surface or attack raised areas. Compared to the stone I ground flat they are a little more dull/slow in removing raised material. I think they are a good alternative to the precision ground flat stones if one didnt want to pay 500$ or has no surfacegrinder... That said, I have currently 7 pairs of stones waiting to be ground..

[@ROBRENZ]

Great! just watch out for retained stress in the stones. If you remove very much material to get them to clean up they seem to move quite a bit. I had to do two both sides twice on mine to get them to behave.

[@felixf5211]

This may be the most influential machining video on YT. Who'd even heard of the stones before this? Yes, I was using honing stones for various applications, but this is whole different deal. The vid came up in my feed; hard not to watch again. Now I own 3 pairs of diamond ground stones in various configurations. So remarkably useful. Just yesterday, got some inexpensive 1-2-3 blocks in the mail. One didn't indicate within spec. Ran the side of the block lightly on a stone and what do you know, meets spec.

[@mgbrv8]

Mr Renzetti As usual thank you for the amazing content of rare uncommon knowledge. I am always excited about any and all of your new content. thank you for sharing Dave Hetrick

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@turningpoint6643]

Hmmmf, now I'm pretty much disgusted and disappointed with how little I actually know instead of thinking I knew at least a bit Robin. Fantastic video and I sure wish I could give more than the single thumbs up.

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@Goodwithwood69]

1. Cross check your measurements with a lesser accuracy gage 2. Always push on your indicator stand to see if the needle comes back to the same spot 3. Don’t assume your grinder ways are worn out when you can’t hold size anymore, it might be your tailstock that’s worn out. 4. Invest in taper stones to remove burrs and scratches from center adapters and tool holders 5. Don’t necessarily believe the gage with the highest resolution 6. Always wring up 2 stacks of gage blocks 7. How you hold on to a part is probably going to be your greatest source of error 8. A 3 jaw chuck doesn’t necessarily bend your part 3 lobe 9. 60 degree centers are a gift from God 10. Check to see if your indicator tip is loose 11. Look for flats on your indicator tip 12. Counter drill your tapped holes 13. Bigger screws don’t necessarily make for a better bolted joint 14. Ground surfaces go together better than lapped surfaces 15. Put light bulbs inside your machine base to keep the base from getting too cold in the winter 16. Remember that you are a big source of heat 17. Make sure you soak your part long enough before you measure it 18. Always stone your parts 19. Always stone your surface plate 20. If you want to do a very fine infeed try bending your machine 21. A soft hammer works well to move a plain way machine slide a very small amount 22. It is perfectly reasonable to level your machine 23. Balance your grinding wheel 24. Most machines can be made to be much more accurate by replacing the work spindle with a Blockhead air bearing 25. Don’t necessarily assume that your spindle is bad because your parts are 26. Everything is rubber when you measure in microinches 27. Get yourself a good used Mikrokator 28. Most machine tool slides are very well made; the biggest deficiencies in most machine tools are their work spindles and their tool/work holding 29. There is nothing magical about 20 degrees centigrade; what you really want to do is avoid temperature gradients and fast temperature changes 30. Don’t pour warm coolant over a cold machine and expect not to have trouble 31. Don’t pour cold coolant over a warm machine and expect not to have trouble 32. Check your gage calibration over the range that matters to you 33. Electronic gages need good batteries even when you have them plugged in 34. Invar’s coefficient of expansion is as far away from steel’s as aluminum's 35. Worry about your material’s thermal conductivity as much as you worry about its coefficient of expansion 36. Know what you are measuring; often what you think you are measuring is different from what you are actually measuring 37. Generally the more massive your indicator mount is, the better your measurements will be 38. Make sure your screws are properly tightened 39. Things bend when you tighten screws 40. Collets only work correctly when your part is the right size 41. Your spindle’s drive is very often the main source of spindle error motion 42. Air regulators are not created equal; get a good regulator and consider cascading if you want to do precision work on an air bearing spindle 43. Don’t necessarily believe your diamond grinding wheel salesman; he might want to sell you a wheel that lasts a long time and your parts might be better with a less durable wheel. 44. Running your grinding wheel at a slower speed sometimes gives you better parts 45. Don’t run your wheel at your machine’s natural frequency 46. Lessons learned from diamond turning don’t always transfer to other kinds of precision machining 47. Donaldson Reversal isn’t a very practical a way of separating spindle error from ball error 48. In spindle testing it is very important to have your master sphere integral to its mount 49. Running your CMM slower can increase its accuracy; the formula that tells you how accurately you can measure with your CMM assumes fairly fast measurements 50. Granite Dents

[@ROBRENZ]

I have that list from PI also. very good stuff but I don't agree on a few items.

[@Goodwithwood69]

Glad to hear from you! Hopefully more content soon!

[@CalvinoBear]

@@ROBRENZ I would be very interested to see what you disagree with.

[@paulaitchison4912]

Ignore comments with too many characters🙄might try too imply a false sense of knowledge.

[@thomasutley]

Every Robrenz video I watch reprioritizes my tool wish list. Now a surface grinder is up to #3 behind the lathe and mill. Another excellent, knowledge-packed, well-explained lesson. Thanks Robin!

[@ROBRENZ]

Thanks and you are welcome Tom,

[@GGTV10]

As 11 years of being precision grindin operator... I can say is 👏

[@James-fs4rn]

How do you insure that that the surface grinder diamond wheel is true and flat? Thanks for another amazing video Robin!

[@ROBRENZ]

I am doing a follow up video where I will cover this

[@pierresgarage2687]

Hi Robin, This is a video packed with serious knowledge, I've picked up lots of details that will help me to improve my work... ;) What about ruby or jade stones for ultra fine work? Is there any other way than a diamond stone to prepare them on the surface grinder, meaning less $$$ involved...??? Sincere thanks for taking the time to put his up and sharing, Pierre

[@ROBRENZ]

Hi Pierre, Shars sells diamond wheels pretty cheap and as I said nothing works as well as grinding the stones. Thanks for stopping by, ATB, Robin

[@keithhansen3963]

After watching this I while back I finally got around to completing a set for myself. Thanks for the inspiration and tutorial Rob. Really don't know how I've lived without these for all these years.

[@gregbrodie-tyrrell3473]

Excellent stuff, Mr Renzetti! Thank you very much! As other blokes have said, it's amazing what you don't know until somebody knowledgeable tells you, but you just did that.

[@mattc8313]

So are those alu oxide India stones you used ? Thank You for all the work you do making these videos, your content is top notch 👍

[@johngamal141]

Great video Robin, I am wondering if I can use widthworth 3 plate method to generate perfectly flat planes. Just buy 3 stones and use the same sequence on rubbing both faces using diamond powder between them. What I know that this method only works well in square and round geometries not rectangular..

[@ROBRENZ]

Correct, square or round would be best

[@jimlandes1801]

@@ROBRENZ I purchased three Norton IB64 stones with the idea of using the Whitworth method to flatten them. Any ideas on what abrasive would be good during the process? Do I need abrasives (i.e. will the stones just make their own?). I am concerned that added free abrasives would be embedded in the stones resulting in an overly aggressive action resulting in the stone removing more than just the high spots. Thank you for your awesome content! ** Update of Impatience ** I found some 600 grit silicon carbide from a rock polishing kit and use it as an abrasive. The IB64 stones are round (4" x 1" thick), and after about 2 hrs of the Whitworth 3 plate method the stones 1) glide over flat surfaces without making any scratch or hazing marks and 2) "catch" on surface imperfections and remove them. All that said the three stones cost me about $70 shipped and I'm happy/amazed with how well they work and I've cleaned up a variety of things around the shop. I'd like to get an optical flat and monochromatic lamp to see how flat they really are, but I'll be content (for now) with them working as desired. Best Regards and Thanks!

[@rocksolidhugo]

So much knowledge in every video. Thank you for taking your time and shooting this. Hugo in Portugal

[@1100Bigmak]

Flat stone are great, thanks for the video. I didn't have a regular diamond wheel so I tried mounting my cup wheel and held the stones vertically. The turned out just fine. Thanks again, Robin.

[@patrickhennigan9689]

Quickest method I've ever learned cleaning stones is with spraying WD40 on cardboard then rubbing the stone on the cardboard. Sucks all the crap right out.

[@TylrVncnt]

Great tip

[@mxcollin95]

Hi Rob, awhile back you mentioned that you were going to start producing and selling these stones for cheaper than the Precision Instruments' stones. By any chance have you started selling these flat stones yet?

[@ROBRENZ]

I will definitely be selling them but it might be several months before I get my first production run done. I will do a follow up video when they are available.

[@saf3ty3rd]

Sadly, I don't have a surface grinder in my home shop. I would definitely be interested in buying a set or two.

[@ptman3]

Fantastic Video. Thank you for taking the time to put this together.

[@howder1951]

Wow! Man have I learned a lot with these groups that have gone through the scraping classes in the youtube community, now this just adds to the depth of that same knowledge. This stoning technique is definitely the icing on the cake so to speak! You have a great talent for explaining these fine techniques, thanks Robin!

[@ROBRENZ]

Thanks howder1951 and thanks for watching and commenting!

[@ianjoubert7505]

Robin, this video was long overdue, please dont have such long intervals between videos, I think most people can learn something from you, even if you film yourself cleaning the shop it will be educational! Thank you, Ian South Africa

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@BuildSomthingCool]

Great Video! Your getting more views then I am. :-)

[@ROBRENZ]

Thanks Dale, as you well know that varies a lot with topic. Thanks for stopping by. ATB, Robin

[@sharkbaitsurfer]

Wonderful video Robin, thank you for taking the time to detail all of that so thoroughly

[@moms762]

Wonderful video, now I can go to work and tell everyone they are using the "as bought" stones for the wrong purpose, IE: destroying surfaces instead of making them better. I will make some of these in the tool room.

[@xyzzyx6468]

This is what 99% of machinists, mechanics, technicians, whatever - do whole life (they thing, brand new stones are "perfect")...

[@placidesulfurik]

I'ts 1-6-6 bro

[@sawduster121212]

What coolant are you using on these stones? Thanks

[@ROBRENZ]

Houghton 795-MP

[@sawduster121212]

@@ROBRENZ Thanks for the information and for producing this excellent video

[@rogerjohnson5798]

Thanks, Robin! Your video has provided the answer to a common shop problem I've struggled with for years. Not having the tools to make these myself, I took a chance and bought a set on eBay. I was pleasantly surprised at the quality of the stones. They worked great on parallels, toolmakers vices, machine tables and various slightly bruised precision tool surfaces - removing just the "bump" without marring the general surface. The seller included instructions and credited you, giving a link to this video and recommending your other great videos. I can't thank you enough for the knowledge you've shared in your videos!

[@sharkrivermachine]

Every time I watch one of your videos I realize how crude my machining techniques are. However I am in the market for a small surface grinder to step my shop up a notch. Thank you for sharing.

[@ROBRENZ]

Thanks R. Steven Lang and thanks for watching and commenting!

[@chronokoks]

soooo... how do you dress your diamond wheel?

[@ROBRENZ]

I will be doing a follow up video.

[@Factory400]

Do you know anyone making these for less than $500 per set? I don't have a grinder - but would like to have a set.

[@ROBRENZ]

I will be in a few months. Thanks for watching and commenting.

[@Factory400]

Sign me up! Any estimate of cost? $200? $250? $300? :-)

[@remz473]

ROBRENZ I'd be very interested as well, diamond wheels are hard to come by for me. I'll keep up and listen for an update. Thanks for the great videos.

[@MachinistGuru]

Absolutely amazing! In the 30 years I've been machining, and I've just now run across this. I've always known the stones we used were not flat, but I've always just tried to find the flattest one of the bunch and take good care of it. After watching your video I had to make a pair to see for myself. This turns the stones into completely different tools. Thank you for schooling us, Mace

[@ROBRENZ]

Glad you found it useful. Thanks and thanks for watching and commenting!

[@ronpeck3226]

Rob, With all the scraping, honing, lapping and polishing being talked about. Your timing is spot on! Thanks for sharing

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@xyzzyx6468]

Actually, there is no full information about real polishing (which is not only "shining things up" as 99% of people think, it's about keeping geometry too)!

[@btodoroff]

LOL, nope 1-6-6 block...😂

[@J0Gu7]

$500 and they don't come flat?????

[@andrewlesuer3504]

The non flat/stock stones are 10x cheaper, the 500 pricetag is for already flat ground stones.

[@outsidescrewball]

Happy Easter Robin...just got my stones from Lance, awesome tool, watched this video again for a refresher course on use and care...

[@OORAH659]

Thank for sharing your knowledge that humans are still needed to perfect a flatness better than a machine ... We The Few will learn more from you for now on....OORAH!!

[@Beanpapac15]

Thank you so much for this video Robin. I purchased a pair of these stones from an ebay seller and was able to completely rework the bed of the mill at work. A previous individual left a dents on the bed surface and vises that I was able to get out with a couple hours of stoning.

[@DonsWoodies]

Excellent, excellent video. Best explanation of these tools I've ever seen. Retired Tool & Die maker here. Wish I had know of these way back when I started in the craft and couldn't figure out why everything had burrs that were so hard to get rid of without compromising the surface of the tools. Made a couple sets of these over the years and still to this day am amazed at how incredibly well they work.

[@SkylerOlsen]

Wonderful presentation. Thanks for taking the time Robin.

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@natemfjones3865]

I definitely learned something new. Great information and explained very well

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@nathanmasi3766]

I can't say that I've ever thought about stones this way. This was an excellent explanation and demonstration! One thing I enjoy about all of your videos and instagram posts is that I now actively think about the concepts and techniques you've demonstrated and try to incorporate them as much as possible. Thank you for the time and effort you're putting in for us.

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@gregm1457]

Many thanks for this video- had never heard of stones like these. I bought a pair a just did my Bridgeport table. Its 60yrs old, in reasonable shape but has the usual wear- picked up quite a few high spots all over. Will do the horizontal mill table and vises next, and my various blocks.

[@motormaker]

Top shelf content Robin. I look forward to watching this again to see what all I missed the first time through. Good stuff. Thanks for all your hard work and thanks for sharing this hard to come by information.

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@rengecko]

Great insight into a whole new level of flat and smooth, clearly and comprehensively presented as we've come to expect. Thanks for sharing your knowledge and taking the time to make this for us to enjoy.

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@yawpaw9796]

Thanks man! You have so much to say about everything. And the best of all is the content! OMG! Those camera angles and zooms and focus! Always smartin ppl around.

[@ROBRENZ]

Glad you liked it!

[@MrJugsstein]

Rob thanks again for sharing A whole subject that I had never run into and so interesting. enjoyed every minute

[@patwicker1358]

Excellent Robin! I watch a lot of machining videos and it is always nice to find something new like you and Tom Lipton come up with.

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@jimzivny1554]

Robin, thanks for this video, it is a wealth of information that can help raise the quality of our work. I have some stones I thought were flat but now I'll have to start looking at them differently. Thanks for taking the time to share.

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@VanillahGarillah]

I’m just starting my machining adventure (I’m 53 👀). In any case, your videos are outstanding (and humbling). I have so much to learn.

[@veegee24]

Thanks a lot for making this video. I tried this technique with my own stones and it worked great. I bought two new Norton stones (which are nowhere near flat out of the box), then flattened them first against a diamond plate immersed in kerosene. That alone took some time due to how warped the stones are out of the box. After that, I dried them and flattened them against each other. I tested it on my lathe spindle nose and it worked out great! I have some expensive Mitutoyo gage blocks, one of which has a scratch on it from the carbide tip of a micrometer. These gage blocks have a mirror finish. I'm afraid to test out the stones on the scratch though.

[@VoidedWarranty]

after about a month of using them after eeeing this video, I'm seeing a general improvement in the parts that come off the mill! mating the vise to the table, the jaws to the vise, etc... small things adding up to a big improvement! Thanks for this!

[@Smallathe]

You are a wonderful teacher. Thank you so much!

[@williamhamill813]

Sounds good. You are the most talented machinist I have found on you tube. Thanks for teaching us.

[@ROBRENZ]

Thanks William for the very kind words and thanks for watching and commenting!

[@bulletproofpepper2]

Thanks for sharing. Very good information and amazing results!!!

[@rdp316]

Excellent video, Robin. Thanks for the Professional Instruments shout out! I've worked there a long time now, and flat stones make what we do possible.

[@ROBRENZ]

Thanks Daniel and thanks for watching and commenting! Was my commentary accurate?

[@rdp316]

ROBRENZ Yeah, totally! You did an excellent job explaining what makes flat stones so special. I've used them my whole career and tend to take that knowledge for granted.

[@ROBRENZ]

I would love to take a tour through your place!

[@duobob]

Excellent video, Robin. I have been thinking about surface grinding stones. Now I have way more information than I ever thought I needed, and that is a very good thing...

[@ROBRENZ]

Thanks Bob and thanks for watching and commenting! ATB, Robin

[@stephenmurray2335]

As ever Robin the quality of your work is astonishing and beautifully presented. Many thanks for sharing.

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@marcellemay7721]

I've been eagerly awaiting this video. I had made a request for this video in a previous video of yours, when you used one of these stones and mentioned it quickly in that video. Thank you so much for making this video! 😊

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@markstevens9630]

Best of the best! The depth and technical content are Superb. You will always have an audience at this level of expertise.

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@joeldriver381]

This is awesome content. Thank you for the detailed information.

[@OyvindRyeng]

Awesome video, just great. I've been watching machining and shop videos on KZbin a few years and this is the best one by far. I'm amazed of the simplicity and usefulness of these ground pieces of rock. Great job, please keep it up.

[@ROBRENZ]

Thanks and thanks for watching and commenting!

Yet another amazing video! Thanks for sharing your knowledge.

[@ROBRENZ]

Thanks Armandas and thanks for watching and commenting!

[@Simon28298]

Thanks Robin! I was looking foward for this video. I did mine couple monts ago and they do a big difference, the quality of my work as upgrade a lot on the grinder and I feel more confiant when it's time to put part off and on the chuck. Diamond wheel can be a real paine, we bought some vitrify diamond wheel at work and they seem to be a litlle easier to dress flat. Thanks a lot again you're a master of the mechanical arts!

[@ROBRENZ]

Thanks for the kind words Simon and thanks for watching and commenting!

[@886014]

Rob thanks for putting this video up. I'll be the first to admit I thought the whole concept was BS when I heard you first mention them, but your excellent description of how they work has me eating humble pie. An excellent description of the process involved and yet another example of how we can't be so quick to judge on the path of lifelong learning.

[@ROBRENZ]

Thanks Pete, I have learned a lot of lessons like that on here (YT) and elsewhere myself. Thanks for watching and commenting, sorry I haven't had any heighth topics lately ;-)

[@Watchyn_Yarwood]

Glad to see you back! We have missed you!

[@ROBRENZ]

Thanks William and thanks for watching and commenting!

[@JackS425]

This video is a masterclass in not only high precision machining, but any machine setup work in general. I purchased and ground my own set of stones over 3 years ago and i use them all day every day. I make precision fixtures and before every setup I stone my machine table/mag chuck. Before I put any work holding on my machine whether it be a vise or angle plate, it gets stoned to remove any little burs. I have found one good way to clean the stones up is to use some WD-40 on cardboard and "stone" the cardboard. It seems to pull most of the impurities out really quickly. Then I rinse them with some IPA and they're ready to go.

[@stephenmellino122]

Thanks Robin. I really enjoy the content of your vids. You tend to go more in depth on your subjects and its filling in the gaps of things I thought I already knew. I'm new to your channel but will be enjoying many more. Thanks for sharing what you have learned. Thanks Steve

[@ROBRENZ]

Thanks, and thanks for watching and commenting!

[@mrsoars]

Many thanks, Robin. Excellent content!

[@StraightThread]

Robin, another fine masterclass on an elite subject in precision machining. It is very satisfying to attend your lectures and demonstrations because you present things so clearly and understandably. The characteristics and use of the ground flat stones are simply fascinating. Though intuitively one might not expect the results produced with the ground flat stones, after hearing your explanation it makes perfect sense. Very well done, sir!

[@ROBRENZ]

Thanks Richard for the very kind words and thanks for watching and commenting!

[@Brian-ug7du]

Thanks for making the videos. I have to watch them several times to take in all the info. I hope you find the time to make many more for years to come! Brian

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@ianpendlebury3704]

Excellent as usual - I always learn so much from your videos - thanks for taking the time effort to produce this content.

[@ROBRENZ]

Thanks and thanks for watching and commenting!

[@DawidKellerman]

I am waiting for my small surface grinder so I will be watching as much of your videos as possible this weekend! I can unfortunately give only one thumbs up your video was brilliant an I hope to learn a lot more from you! Thank you! so much for taking the time to make it

[@ROBRENZ]

Thanks, and thanks for watching and commenting