Been a carpenter all my life , only once i started fooling with furniture did i need a flater area to sharpen my tools . To get a better edge. I never gave it any thought on how they got that metal flat the first time. Amazing , thank you
@@_FJB_you have a big pool of molten metal and slowly pour molten glass ontop, where it "floats", then let it cool down to where the glass gets solid but the metal is still molten. The glass will be super flat on the interface side
My mind was blown as a young man when I first learned about hand scraping precision flattening. Initially, it seems impossible to get something perfectly flat by such a “crude” process, but then you see the labor involved and how little material is removed at each step and it makes sense. I appreciate your dedication and willingness to share with us.
I'm a retired machinist, welder repairman. Part of my apprentice training was learning how to hand scrape Amco bronze round bearings that had an inside diameter of 8 in. Also learning how to scrape flat bronze wear plates on a thread rolling ram. It is slow time consuming and very physical. You scrape until your forearms are burning. Rest 5 minutes and scrape some more. That was 60 years ago. I still have those forearms. 😂😂 2:48
Just love the visual image of a micron-reading mechanical gauge used in conjunction with a wooden rule to establish the data for drawing the graphic. Good work.
Ever since I learned of this technique I wanted to re-scrape the ways on my mill. It's been many years and I've since switched from one clapped out milling machine to another one, but have yet to try it. I think I may be able to get to this soon. Thank you for sharing. This is inspiration.
There's a Russian machinist on YT who had to scrape his mill's ways but he said you didn't want them perfectly smooth, but rather to scrape so all the high spots are equally flat, so there's 6 points of contact to minimize friction. I'm not sure exactly what he was getting at but might be relevant research for you!
If you ever scrape in the ways of your lathe pleaseeee don't forget you have to make them flat and then scrape in oil bearing marks into the flat ways or you will kill lathe extremely quickly. Lathe ways are flat but have small low spots to retain oil into the ways
@@cheyannei5983it's to do with the ability for the ways to retain lubrication if you make them too smooth oil doesn't adhere to the surface and you end up with metal to metal contact which will kill your lovely hand scraped ways
As someone who barely knows anything at all about machining it's incredibly cool to see a process like this being done by hand. It gave me an idea, which might either be a lot of unnecessary work or kind of cool: making prints of the printings, i.e. after each pass, laying a sheet of paper into the metal after the printing and rolling it down like printmakers do (which would no doubt force you to reapply the bluing, hence the extra work!). I could see this making a really cool series of art prints, plus it would be an amazing way to graph the progression of the flattening of the surface.
Very few craftsman know how to do things like this. I've met about 2 that can do everything you did in this video. Grinding your own tools, the scraping itself is a super rare skill now, and the measurements. Reminds me that i still have a very long way to go in my trade before i can claim I'm even half as skilled as a craftsman like this.
I think, seeing the whole picture, there is too much to learn for an entire lifetime. I think the real "skilled" craftsman is skilled, because he knows how much there is to learn, keeps and open mind and is always interested in learning new things. Adam Savage wrote in his book 'Every Tool is a Hammer': "Dig through the bottom of that rabbit hole!" - And what that means is, to not just touch surface on things, but really dig into it, until you get the feeling that you really have a clue what's going on. And then, repeat on other topics. Stay curious, that makes it really easy in my eyes.
@@buildfromsketch8102 every tools a hammer is a book I listen to at least once a year. Such a beautiful grounding Bible for anyone on the journey of making things.
For some reason, when I read hand scraping and saw the thumbnail, I thought you were literally going to rub the thing with your bare hand and some grinding compound. My brain is scaring me
that was my first assumption too but then i thought if the steel is getting noticeably smoother how will your hands look ? they are getting grinded with just as much force if not more
Fun fact: When the first precision flat plates were first scraped, using the three plate method which ensures you will not develop a radius... It brought us into the industrial revolution. It was needed for the ways of lathes, and then, in turn for the ways on machine tool mills... And here we are. This was the handicraft skill that launched us into the modern world. Without it, we wouldn't have had the lathes and mills to help us develop steam engines.
Watching this, I was thinking about exactly that problem and came up with exactly the same solution. I guess there's pretty much only one way to do it.
I have never liked Prussian blue for printing, it's very hard to read. Instead, use copper sulfate solution. The approximate formula is 150 ml water, 2 g copper sulfate, and 1 g of weak hydrochloric acid (sulfuric also works). Wipe the solution on clean dry metal plate with a clean paper towel, it will instantly turn lovely dark copper color. When rubbed on the surface plate, the high places are shiny and very easy to see. On the next printing, just wipe solution on the bare metal you have scraped. No worries about your surface plate, It will not damage it in any way.
This seems like a great deal of work to build an air hockey table. But seriously, my regards to you for the patience and the results you've achieved. I don't _need_ so large and precise a surface plate, but I'm glad I now know what it takes to manufacture one.
Great video, thank you! The half-moon could be where the slab of steel got hit hard with a hammer of other tool late in its manufacturing process. I made my lapped plate using an ultra-precision spirit level instead of a Mahr gage. It came out at about 50 microns, I only needed about 130 microns flatness (for woodworking). It surprised me how accurate the spirit level was, I could have achieved probably 10 microns pretty easily.
I recently brought home a hand scraped surface plate from a local metals recycler. I don't currently have any use for it, but I felt that i had to preserve it for for the huge amount of work and effort in the quest for precision that it represents. Great video!
I never would have guessed it was such an intensive manual process. I always assumed two blanks would be automatically ground together with progressively finer grit.
@@buildfromsketch8102this is what I really want to see, ever since I learned of it back in uni decades ago. Why no one else thought it was worth recording, I don't know.
"...I don't have the money to do that and I don't see why." I understand what you meant in context, but I like that phrase out of context a lot more! haha
Ive just recently aquired my own space for hand work, soon I'll be teaching myself steel scraping. Its always helpful to see somebodies methods and philosophies on something so experience *and* technique oriented
I grew up in job shop machine shops, quite literally. Every time I've seen any of the machine ways and tables getting scraped, they did it in more than two different planes. Also, they typically used a much finer tool for the ways.
I'm in the second month of my apprenticeship and I filed down a hunk of steel to .1mm tolerance and am proud and kind of surprised of myself. I can't imagine the patience required for a project like this.
Wow....can we say "Zen Exercise"? I understand the value of an absolutely flat refference surface. And seeing the labor, and time required, only makes me feel confident in saying the satasfaction level in a job well done has GOT to be off the charts. Awesome.
I have no desire to scrape myself a surface plate, but knowing how it is done is a nice technique to file away for a repair in the future. Also 47:00 - Pauli would be proud!
That hard imperfection you describe at the start of the video, might be not fully melted pieces of bearing races/drill bits/reamers/taps/files/etc. that were used as scrap steel raw material to make that plate (I encountered this in "cost-effective" Taiwanese cast iron, as example, that I had to scrape as a machine builder).
by distinguishing the country where it is made, you could now step up on some politicly sensitive toes, Most of the "cost-effective crap" is coming nowadays from China ( no to confuse that with Taiwan, that would be the same as you say the Mose meat from the USA is crap.... but it came from Canada ) but if they build shit In Taiwan they do deserve the notification....
@@freddykoopmans6985 it arrived from Taiwan, as far as I know, but I have no clue where it was actually made. And I'm not really blaming them for it - who can sort through tons of chips and chunks of metal looking for files and ball bearings before dropping into smelter?
Excellent demonstration of the process! I’m puzzled by the scrapping technique as you’ve shown many times that areas WITH ink are high spots! In my experience with auto body, spots where I had left guide (ink) were supposed to be the low spots. Could you go over that part to explain why scrapping is the reverse? Thank you very much!
@@roadshowautosports It is reversed because the marking medium is put on in reverse. In scraping, the marking medium is put on the perfectly flat reference surface. When the work piece is put on, only the high points touch and transfer the ink. In auto body work, you put the guide coat on the work piece that is not flat. Therefore the guide coat flows into the low spots. Your sanding block is the "perfectly flat" reference and only sands the high points, leaving your guide visible in the low spots.
Amazing video. I didn't know that microns were so "big", coming from a computer background. I had no idea they were physically measurable in such a way. Awesome!
I have experience of scraping a straight edge made of mild steel. If the total flatness of the part is more than 0.02mm it takes days and weeks to make it flat. First of all we must make it as flat as possible with surface grinder and then start scraping.
Really, weeks? 8 hours of scraping every day? I've heard using a surface grinder will make it too "slippery" to get it going. Some prefer even a milled surface
@@valkman761 he wasn't suggesting the grind be the final surface, just to save time when scraping. though I kind of disagree on his time table, that table just isn't that big, 0.2mm is like 8 thou, right? its a lot, but its a few hours, less with a power scraper. I only mention this because a lot of people dont have access to a surface grinder, or the part it too big--in those cases, you can scrape 10's of thous pretty quick...plus its about the only way. Yes, smooth surfaces do tend to be prone to stick slip, but on a surface plate, you really want a smooth (which can be scraped) gauge quality finish. If you got a plate like this ground & it was done with acceptable geometry, you could just do more pattern flaking to make it slide smoother.
39:14 I can only Like your video once unfortunately. Great edge case. Reminds me of Top Gear - the longest straight racetrack. The end isn't visible from the start because it follows the curvature of the earth. Patience of a saint!
I am curious how you overcome the dynamic and constant and irregular deformation of the plate subsequent to random thermal changes, you know, a forearm here, a palm there, a gust of cold air from a door opening etc.
Touching it will not do much, as the heat is conducted internally inside the plate pretty fast. Cold air and temperature changes in general are indeed an issue. So keeping the door shut and doing the final scraping during a time, with minimal to no thermal drift is a good idea.
Mild steel if it has been cold milled(rolled), you must anneal it first, otherwise will be milling stress left on both sides of surface. This stress trend to curl your surface as you try to wear only one side down.
Yeah, that's pretty much true for all materials. Also for cast iron. The cooldown process is the most critical thing. Warping in my case is not really a problem, because the plate was precision gound on both sides (ground without magnet-clamping on first side). There might be still some stress in the plate, but as long as you don't heat it up locally or release the stress by removing a significant amount of material (by milling for example), it will not affect the plate. This is one of the biggest advantages of scraping: the amount of material removed is very small and almost no stress is induced into the workpiece (at least compared with all other proccesses).
That half moon is most likely a spot of impurity from the steel manufacturing. S355 is a low-alloy structural grade material. If some piece of high-alloy scrap made it into the mix, it could have failed to mix with the batch and ended up creating a hard spot in the plate.
Most carbides are highly carcinogenic and generally never leave the body. Id recommend wearing disposable gloves and a respirator when grinding any carbode. If you gave a way to wet grind it aswell that is even safer
@@dm55american citizens don't really have control over this right now. Hopefully we'll stop being stubborn at some point. Life in the manufacturing industry would be greatly improved by a unified system. 2 sets of tools for the 2 measurement systems is really annoying.
The surface plate (granite) is smaller than the piece you doing. I'm new to this, so I ask if it would be safe put a larger piece on a smaller reference surface. If it is, how to do it safely? The larger piece I intend to do in the future is a ML Myford bed (about 1 meter length). Thanks in advance!!
Hey there! The granite plate i used is a little bit bigger than the plate i scraped. Generally, you can scrape a larger surface with a smaller reference, but your result will be less accurate. You can move the reference in overlapping intervals and also use a micron indicator on the reference, to double check for deviations.
Hi there, that sounds like a lot of work. You may want to consider having it reground before. Anyways, as long you are not aiming to replicate any NIST standards in you home garage, some lowspots are absolutetly ok. The plate I scraped here isn't perfect either. As long as you lnow your plate, that's totally fine for some work you do at home :)
I have the exact same issue, I bought a pair of cast iron surface plates and a camelback at an auction from a former technical college. The camelback was covered in a moderate layer of rust, clearly not having been used in a long while and not having been stored covered in oil, and those surface plates were especially dinged up. We have a lot of projects planned where we need precision references and thus we now have a couple side projects to acquire ultra precise (
@@pieterveenders9793 , Hey there. The issue is that the Whitworth three plate method requires three plates, as the name already indicates. It's also required to have the ability to rotate these plate by 90° in order for the plate to work. Robin Renzetti has a good video, explaining the problem using some kitchen sponges. Nevermind, if that's what you are aiming for, things will require a full regrind first, then copying everything off a known good plate, then Whitworth-scraping it using a third plate. Finally a lapping step may be required to achieve 5µm/1000mm.
Just to add that the youtube channel "an engineers findings" also explored scraping steel and came up with some conclusions on scraping angles that worked (at least for him)
Never done any of this (to speak of), but I found another guy who scraped steel. He suggested a totally different tool geometry, since the blade tend to dig in on steel. Yours look very conventional though, as used on cast Iron? Beautiful video though, I will watch it again!
Yes, i found that video as well, after I made this plate. He is completely right and his tool geometry is definitely better. I personally didn't experience the work hardening as a big thing. I am sure it reduced tool life a bit, but it wasn't unbearable. I also talked to a guy who does a lot of professional scraping, and he said he just runs with a 0 degree angle. So yeah, it's a thing, but nothing to overthink actually.
Just out of curiosity. Is there any reason not to use lapping tools to make it more flat? Like the way they use them on granite surface plates. Is it because of the difference in material or is there some other reason?
@@Chris-io2cs Good question! Yes, you can use a lapping plate to continue, and therefore make it even flatter. But the problem is, you need a lapping plate in the same or bigger size. If i had three plates of the same size, i could rub them against each other with lapping compound inbetween, which would increase the flatness. I have an upcoming video where i will show that!
Thanks! :) This is my daily shop plate that I use for lower precision measurements of small and medium parts, as well as a marking plate for scraping lines onto workpieces, for example to precisely mark holes I want to drill into stuff :) I made it, so i don't risk damaging my granite plate or wearing it out. But for really high precision measurements, I still use the granite plate from time to time.
Did you measure how much the drilling and tapping the side distorted the top surface? It looks like that area was low, relative to the highest parts, so it didn't affect thr result, but it would have been interesting.
No, I actually didn't measure that. I will do once I have have time for that. Good idea! But as you already said, it wasn't high so it didn't affect the end result :)
Thanks! I used a +5 degree angle, which as I found out later is not ideal. You actually would aim for something like a -5 degree angle, as I found out from some very old literature. Nevermind, for me it still felt okay to be honest. I also talked to an oldschool scraping guy, and he used a 0 degree angle for steel, which seemed perfect for him personally. So yeah, -5 degree by the book, but you can get away with other angles as well :)
Can you automate the scraping with a gantry or robotic arm? I'm guessing flaws in machines might translate onto the plate, but I'm also wondering if one might slightly randomize the movements of the machine a bit, and calibrate each run manually with data input from your ink printing method. I.e. don't automate the whole process, just help some of the monotony.
Well it's monotone, but it clears your mind :) But automating it is hard, as you need a camera to detect the highspots. But that's next to impossible, as cameras and scraped surfaces are not working well together. But there is also no commercial application that would justify the automation...
Very nice video. I enjoyed it very much. I have limited experience scraping. I've scraped some of the ways on my milling machines and lathe, as well as a 635mm steel straight edge. Scraping steel is much more difficult than cast iron. When you were scraping this steel plate, you probably took heavy, medium, and light scraping depths. What do you think those depths were? Thanks.
Well, it is stiff indeed. It worked out for me anyway. Here in Germany I actually have never really seen the more flexible scrapers. But I know they exist. I would like to test them out in the future :)
@@martinnovak3949 It's 25mm. Altough I used a 30mm carbide blade in the beginning (it's sticking out quite a bit). 25mm seems to be a decent allround size, although it's too big for smaller things.
some wise guy said: if want something done well you have a few choices: 1# pay somebody to do it, #2 do it yourself, or #3 tell your kids not to do it. For nr 3 i do not trust my kids to get their yogurt in an 8" bowl so forget about something about microns... for pay someone to do it for you without you can check their work......... that is only a good plan if you have money to spend and you know what they do and you can check there a process. heads off his efforts and ill think he did a pretty good job
The godfather hasn't spoken yet, but maybe you are right and he is sitting in his basement right now thinking: "Well, this is a reasonable quality plate."
It is interesting how were made rotary parts like spindles or shafts of the first machine tools in the world. I've been always thinking about it. My question is: is it possible to get a cylindrical part using this method?
Hey there! Good question! Yes, you can also scrape round parts, for example bearings and spindles. The first machines were made from wood, with a primitive spindle that was made by hand, carving a round part out of wood. When steel was invented, they filed and scraped round parts by hand. They again were used for the first lathes. At a certain point it was possible to make more precise parts with the machine, than by hand. From this point on they used machines, and hand work together to build more and more precise machines, that again could build more precise machines. But all precision comes from a flat reference: the surface plate. You can use a surface plate as reference to build everythin you want. And you can make a surface plate by scraping it, using the whitworth three plate method.
gr8 work here, you should continue on this plate with lapping, you will get sub micron if u did so, use a precision machinist level it can sense 1um curvatures but u will need very solid base or measure on bare ground, the dial measure you have used is not really for flatness it is for uniformity, imagine u r using the same setup on a perfect sphere you will still read zeros, also i never liked the neutral/positive rake angles on the blade on that video, it does a lot of biting, even on the video it shows that, not sure why the guy and everybody was happy with that, btw about the diamond wheels, how you control the run out on them? do they come with a convex curve so when you bolt them to the grinder they become flat? how that is addressed?
Hello there, thank you very much! You do have some very good questions. You are right. I did talk about the measurement theory in the video as well: 34:49 The blade angle is something that somebody already suggeested to change to 0° or +5°. I will try this the next time when scraping steel. The runout of the diamond disc is not controlled at all. It's just a cheap diamond wheel off ebay- mounted to a wooden plate. The runout is not critical.
@@buildfromsketch8102 got you, will wait for your experiment with a 0 or +5 rake coz it really did not work with me at all, thanks for your reply, keep up the good work!
There is a way of measuring two (any) surfaces to the precision of the dial gage, it is called reversal method. Can be done with 2 dimensional surfaces but works best with narrow beams: Put two beams side by side and measure one agains another at equally spaced points. Flip one and measure it from the underneath at the same points. Take the slope out of the two series of measurements. Essentially make the points the deviation from the slope. First beam is the average of the two measurement series. Second is the half the diference of the two measurement series. There is a video on youtube by Dan Gelbart: (Reversal method at the end) ruclips.net/video/cwdoUjynpEk/видео.html To avoid flipping one beam, 3 beams and a fixture to rest the the dial on the outside ones and measure the one in the center. After the 3 permutations of the center beam there is enough data to determine the 3 of them. Hope I was clear enough.
Hey there, thanks for your comment! Yes, you are right. The way Dan Gelbart is showing in the video, is a great way of doing this. Unfortunately I don't have a surface plate that is big enough to cross-check my hand scraped one. But I will revisit this surface plate in the future and do some more measurements on it! :)
I believe the important thing with local flatness is not having the feet of test instruments falling into holes- so test with a 10mm / 3 /8 foot is the standard way to go
The more standard way is to use an instrument holder with a flat lapped base or use a ``repeat-o-meter``... Also, using of gauge blocks is the norm with some measuring methods, if scraped surfaces are in question... The feet are more for general purpose high precision measuring, but for stuff such as this, lapped, instrument grade surfaces akin to gauge block ones are used... The instrument base may be machined as to provide a reduced surface, as in faking feet of larger size, but the end result is lapped... Either way, for madly flat surfaces, you dont even want feet, a large flat lapped surface is preferable, as it will indicate any shift due to any positive extreme anomaly however small on a larger area... Which is what large repeat-o-meters are practically designed for, just like the auto-collimators, but in a different way of doing it, its a bad comparison, but a somewhat adequate one...
Been a carpenter all my life , only once i started fooling with furniture did i need a flater area to sharpen my tools . To get a better edge. I never gave it any thought on how they got that metal flat the first time. Amazing , thank you
Thanks for your comment and watching! :)
Really like to hear, that a rather dry topic like this, spreads so much joy in the world!
Pleasure!
Depending on what tools we are talking about here, float glass is super flat and works perfectly with the sandpaper based "scary sharp" approach.
@@MrJofArnold"float glass"?
This has been on my mind for maybe months if not a year or more now. Hoping this video will finally give me answer.
@@_FJB_you have a big pool of molten metal and slowly pour molten glass ontop, where it "floats", then let it cool down to where the glass gets solid but the metal is still molten.
The glass will be super flat on the interface side
[ ] Sleep
[✓] Watching a man flattening his plate
That's the spirit!
Literally me at 1:33am😭😭
lol 1:43am for me
3/4 of an hour well spent.
i cant believe i watched a man scrape a metal plate for 40 minutes, and i liked it
Glad you liked it!
1 minute for us represents 1 hour of actual time
My mind was blown as a young man when I first learned about hand scraping precision flattening. Initially, it seems impossible to get something perfectly flat by such a “crude” process, but then you see the labor involved and how little material is removed at each step and it makes sense. I appreciate your dedication and willingness to share with us.
I'm a retired machinist, welder repairman.
Part of my apprentice training was learning how to hand scrape Amco bronze round
bearings that had an inside diameter of 8 in.
Also learning how to scrape flat bronze wear plates on a thread rolling ram. It is slow time consuming and very physical. You scrape until your forearms are burning.
Rest 5 minutes and scrape some more.
That was 60 years ago. I still have those forearms. 😂😂
2:48
I feel you, the pain is real :D
I think I’d be more worried if you didn’t still have them 😅
@@Googahgee I think he meant the strength and/or muscle gains 😂
@@_..-.._..-.._
That's exactly what I meant.
👍👍👍
@@_..-.._..-.._ wooosh :D
Just love the visual image of a micron-reading mechanical gauge used in conjunction with a wooden rule to establish the data for drawing the graphic.
Good work.
Not only that, but a folding ruler. I haven't seen one of those for 40 years.
Ever since I learned of this technique I wanted to re-scrape the ways on my mill. It's been many years and I've since switched from one clapped out milling machine to another one, but have yet to try it. I think I may be able to get to this soon. Thank you for sharing. This is inspiration.
Thank you for watching! :)
There's a Russian machinist on YT who had to scrape his mill's ways but he said you didn't want them perfectly smooth, but rather to scrape so all the high spots are equally flat, so there's 6 points of contact to minimize friction. I'm not sure exactly what he was getting at but might be relevant research for you!
If you ever scrape in the ways of your lathe pleaseeee don't forget you have to make them flat and then scrape in oil bearing marks into the flat ways or you will kill lathe extremely quickly. Lathe ways are flat but have small low spots to retain oil into the ways
@@cheyannei5983it's to do with the ability for the ways to retain lubrication if you make them too smooth oil doesn't adhere to the surface and you end up with metal to metal contact which will kill your lovely hand scraped ways
As someone who barely knows anything at all about machining it's incredibly cool to see a process like this being done by hand. It gave me an idea, which might either be a lot of unnecessary work or kind of cool: making prints of the printings, i.e. after each pass, laying a sheet of paper into the metal after the printing and rolling it down like printmakers do (which would no doubt force you to reapply the bluing, hence the extra work!). I could see this making a really cool series of art prints, plus it would be an amazing way to graph the progression of the flattening of the surface.
Nice idea! :)
Very few craftsman know how to do things like this. I've met about 2 that can do everything you did in this video. Grinding your own tools, the scraping itself is a super rare skill now, and the measurements. Reminds me that i still have a very long way to go in my trade before i can claim I'm even half as skilled as a craftsman like this.
I think, seeing the whole picture, there is too much to learn for an entire lifetime. I think the real "skilled" craftsman is skilled, because he knows how much there is to learn, keeps and open mind and is always interested in learning new things.
Adam Savage wrote in his book 'Every Tool is a Hammer': "Dig through the bottom of that rabbit hole!" - And what that means is, to not just touch surface on things, but really dig into it, until you get the feeling that you really have a clue what's going on. And then, repeat on other topics.
Stay curious, that makes it really easy in my eyes.
@@buildfromsketch8102 every tools a hammer is a book I listen to at least once a year. Such a beautiful grounding Bible for anyone on the journey of making things.
@@buildfromsketch8102I don't trust any skilled worker who doesn't have an understanding of just how much they don't know
For some reason, when I read hand scraping and saw the thumbnail, I thought you were literally going to rub the thing with your bare hand and some grinding compound. My brain is scaring me
You were not the only one actually. But in order to calm you down: I didn't gain any superpowers :)
Honestly that was my first assumption
that was my first assumption too but then i thought if the steel is getting noticeably smoother how will your hands look ? they are getting grinded with just as much force if not more
Fun fact: When the first precision flat plates were first scraped, using the three plate method which ensures you will not develop a radius...
It brought us into the industrial revolution. It was needed for the ways of lathes, and then, in turn for the ways on machine tool mills...
And here we are. This was the handicraft skill that launched us into the modern world. Without it, we wouldn't have had the lathes and mills to help us develop steam engines.
Thanks for the comment!
You're completely right.
I actually have an upcoming video regarding the three plate method ;)
Watching this, I was thinking about exactly that problem and came up with exactly the same solution. I guess there's pretty much only one way to do it.
all hail whitworth
@@buildfromsketch8102subscribing
I wondered why he didn’t just grind 3 different surface plates together
I wasn't feeling well so I re-watched you video, and it's still a beautiful job, and end product.
Thank you so much!
I have never liked Prussian blue for printing, it's very hard to read. Instead, use copper sulfate solution. The approximate formula is 150 ml water, 2 g copper sulfate, and 1 g of weak hydrochloric acid (sulfuric also works). Wipe the solution on clean dry metal plate with a clean paper towel, it will instantly turn lovely dark copper color. When rubbed on the surface plate, the high places are shiny and very easy to see. On the next printing, just wipe solution on the bare metal you have scraped. No worries about your surface plate, It will not damage it in any way.
Looks interesting. Never thought about it this way despite it is all reasonable.
This seems like a great deal of work to build an air hockey table.
But seriously, my regards to you for the patience and the results you've achieved. I don't _need_ so large and precise a surface plate, but I'm glad I now know what it takes to manufacture one.
Great video, thank you!
The half-moon could be where the slab of steel got hit hard with a hammer of other tool late in its manufacturing process.
I made my lapped plate using an ultra-precision spirit level instead of a Mahr gage. It came out at about 50 microns, I only needed about 130 microns flatness (for woodworking). It surprised me how accurate the spirit level was, I could have achieved probably 10 microns pretty easily.
Fascinating. Love that you did this! Thanks for sharing.
Thanks for watching! :)
I recently brought home a hand scraped surface plate from a local metals recycler. I don't currently have any use for it, but I felt that i had to preserve it for for the huge amount of work and effort in the quest for precision that it represents. Great video!
wow, someone that knows how to drill into steel, refreshing.
I thought that too😅
Absolute Handwerkskunst, Präzision und Perfektion. Herzlichen Dank!
I never would have guessed it was such an intensive manual process. I always assumed two blanks would be automatically ground together with progressively finer grit.
You are not wrong, but you would need three plates to achieve flatness. I did that as well six months ago, i need to finish that video though :)
Oh that would be really nice to watch!
@@buildfromsketch8102this is what I really want to see, ever since I learned of it back in uni decades ago. Why no one else thought it was worth recording, I don't know.
Kudos for an incredible patience, I would go mad after 2 hours of scraping.
Thanks :D
Respect ! Scraping such a steel plate is quite a task !
"...I don't have the money to do that and I don't see why."
I understand what you meant in context, but I like that phrase out of context a lot more! haha
That's my golden rule as well when I somebody asks me to get a fancy car, but as you said, it may be way more universal than i actually thought :D
My hands hurt just from watching this video, such a task is a propper workout!
Ive just recently aquired my own space for hand work, soon I'll be teaching myself steel scraping. Its always helpful to see somebodies methods and philosophies on something so experience *and* technique oriented
I grew up in job shop machine shops, quite literally. Every time I've seen any of the machine ways and tables getting scraped, they did it in more than two different planes. Also, they typically used a much finer tool for the ways.
It is interesting how were made first machine tools when there were no machine tools
I'm in the second month of my apprenticeship and I filed down a hunk of steel to .1mm tolerance and am proud and kind of surprised of myself. I can't imagine the patience required for a project like this.
Wow....can we say "Zen Exercise"? I understand the value of an absolutely flat refference surface. And seeing the labor, and time required, only makes me feel confident in saying the satasfaction level in a job well done has GOT to be off the charts. Awesome.
I'm still amazed at the results you can get by hand.
Makes the Egyptian pyramid conspiracies seem funny doesn't it
@@jeremymcadam7400 Definitely.
I have no desire to scrape myself a surface plate, but knowing how it is done is a nice technique to file away for a repair in the future. Also 47:00 - Pauli would be proud!
Very cool project and your determination paid off. It looks amazing...thanks for giving me the bug!!
That hard imperfection you describe at the start of the video, might be not fully melted pieces of bearing races/drill bits/reamers/taps/files/etc. that were used as scrap steel raw material to make that plate (I encountered this in "cost-effective" Taiwanese cast iron, as example, that I had to scrape as a machine builder).
Yeah, that might be possible! Good comment! Thanks!
by distinguishing the country where it is made, you could now step up on some politicly sensitive toes, Most of the "cost-effective crap" is coming nowadays from China ( no to confuse that with Taiwan, that would be the same as you say the Mose meat from the USA is crap.... but it came from Canada ) but if they build shit In Taiwan they do deserve the notification....
@@freddykoopmans6985 it arrived from Taiwan, as far as I know, but I have no clue where it was actually made. And I'm not really blaming them for it - who can sort through tons of chips and chunks of metal looking for files and ball bearings before dropping into smelter?
Excellent demonstration of the process! I’m puzzled by the scrapping technique as you’ve shown many times that areas WITH ink are high spots! In my experience with auto body, spots where I had left guide (ink) were supposed to be the low spots. Could you go over that part to explain why scrapping is the reverse? Thank you very much!
@@roadshowautosports It is reversed because the marking medium is put on in reverse. In scraping, the marking medium is put on the perfectly flat reference surface. When the work piece is put on, only the high points touch and transfer the ink. In auto body work, you put the guide coat on the work piece that is not flat. Therefore the guide coat flows into the low spots. Your sanding block is the "perfectly flat" reference and only sands the high points, leaving your guide visible in the low spots.
Really enjoyed every second of your work. Thank you for sharing your experience in creating something that is so mesmerising to watch. Great work!
Thank you so much!
The heat treating process you're describing at the beginning sounds alot like flame straightening, for anyone interested in the technical term.
Wonderful test of patience. And what a result!
Beautiful. There is nothing like a scraped surface. Thank you for sharing.
Thanks for watching! :)
I don't got nothing to say. You just deserve the engagement.
Amazing video. I didn't know that microns were so "big", coming from a computer background. I had no idea they were physically measurable in such a way. Awesome!
Thanks for watching!
I agree, compared to computers and optics, microns are rather big. Precision is always a question of context in my eyes.
Your fingers can feel deviations as small as 13 nanometers!
I have experience of scraping a straight edge made of mild steel. If the total flatness of the part is more than 0.02mm it takes days and weeks to make it flat. First of all we must make it as flat as possible with surface grinder and then start scraping.
Really, weeks? 8 hours of scraping every day? I've heard using a surface grinder will make it too "slippery" to get it going. Some prefer even a milled surface
@@valkman761 he wasn't suggesting the grind be the final surface, just to save time when scraping. though I kind of disagree on his time table, that table just isn't that big, 0.2mm is like 8 thou, right? its a lot, but its a few hours, less with a power scraper. I only mention this because a lot of people dont have access to a surface grinder, or the part it too big--in those cases, you can scrape 10's of thous pretty quick...plus its about the only way.
Yes, smooth surfaces do tend to be prone to stick slip, but on a surface plate, you really want a smooth (which can be scraped) gauge quality finish. If you got a plate like this ground & it was done with acceptable geometry, you could just do more pattern flaking to make it slide smoother.
If mild steel, take an angle grinder to speed up the process.
I'm a grown man crying. Bravo. God really does have a plan for us all and if this flat surface is not indicator enough i dont know what is.
These are the supertasks i love. Great video btw.
Thank you! :)
Wer viel misst, misst mist!
Absolutely loved the air bearing demonstration at the end :)
Reminds me of the time helped a budy polish a telescope lens
That sounds like a lot of work!
Well done. The air hockey effect at the end was so satisfying. 🎉
Thank you so much! :)
Now it's time to get started on that other side!😁
Großartig! Tolle Arbeit! Und großartig präsentiert. Glückwunsch zum Ergebnis! Hat sich wirklich gelohnt.
Hallo und vielen Dank für die lieben Worte! :)
That's pretty cool, Grownup NialRed!
This is that "true level" that Rick was talking about.
Everyone: "What hobbies do you have?"
This dude: "..."
Can't see anything wrong with that.
Very nice job.
Plate looks Beautiful.
Thanks for sharing.
Take care, EM.
39:14 I can only Like your video once unfortunately. Great edge case. Reminds me of Top Gear - the longest straight racetrack. The end isn't visible from the start because it follows the curvature of the earth.
Patience of a saint!
Oh yes this takes me back to my apprenticeship, had scrap machine slids as a training exercise.... master hand tools before let near machine tools..
I am curious how you overcome the dynamic and constant and irregular deformation of the plate subsequent to random thermal changes, you know, a forearm here, a palm there, a gust of cold air from a door opening etc.
Touching it will not do much, as the heat is conducted internally inside the plate pretty fast. Cold air and temperature changes in general are indeed an issue. So keeping the door shut and doing the final scraping during a time, with minimal to no thermal drift is a good idea.
Very relaxing, really needed this right now
Amazing amount of work.
Thx! :)
Mild steel if it has been cold milled(rolled), you must anneal it first, otherwise will be milling stress left on both sides of surface. This stress trend to curl your surface as you try to wear only one side down.
Yeah, that's pretty much true for all materials. Also for cast iron. The cooldown process is the most critical thing. Warping in my case is not really a problem, because the plate was precision gound on both sides (ground without magnet-clamping on first side). There might be still some stress in the plate, but as long as you don't heat it up locally or release the stress by removing a significant amount of material (by milling for example), it will not affect the plate.
This is one of the biggest advantages of scraping: the amount of material removed is very small and almost no stress is induced into the workpiece (at least compared with all other proccesses).
That half moon is most likely a spot of impurity from the steel manufacturing. S355 is a low-alloy structural grade material. If some piece of high-alloy scrap made it into the mix, it could have failed to mix with the batch and ended up creating a hard spot in the plate.
Yep, that theory came up in some other comments before. It could potentially be a not perfectly molten bearing ring.
We can still recognize you despite the glasses, Superman.
Most carbides are highly carcinogenic and generally never leave the body. Id recommend wearing disposable gloves and a respirator when grinding any carbode. If you gave a way to wet grind it aswell that is even safer
4chan users: "I have the strongest forearms"
Deviantart users: "No, I have the strongest forearms"
This guy: "AMATEURS."
Wondering where the 40 hour super cut is...
This is great. I'm also interested in how the precision granite tables are made as well.
I didn't record the whole thing, but you are not the first to ask :D
does the surface stay flat when temperature or pressure change in the workshop ?
Yes
"What are you doing next week?"
"Flattening a plate"
"Why are you giving me that look?"
- "What look?!"
"Ah, I see, you want to join me!" :)
Just to be clear, .015mm = .000591"
America must catch up with the rest of the world.
@DM55 maybe when the world catches up with us we'll humor your silly little suggestions.
@@dm55american citizens don't really have control over this right now. Hopefully we'll stop being stubborn at some point. Life in the manufacturing industry would be greatly improved by a unified system. 2 sets of tools for the 2 measurement systems is really annoying.
@horacerumpole6912 , thank you.
That's what he said. 0.59.. of a "thousands of an inch".
Qual aço e esta base ou é ferro fundido ???
The surface plate (granite) is smaller than the piece you doing. I'm new to this, so I ask if it would be safe put a larger piece on a smaller reference surface. If it is, how to do it safely? The larger piece I intend to do in the future is a ML Myford bed (about 1 meter length). Thanks in advance!!
Hey there! The granite plate i used is a little bit bigger than the plate i scraped.
Generally, you can scrape a larger surface with a smaller reference, but your result will be less accurate. You can move the reference in overlapping intervals and also use a micron indicator on the reference, to double check for deviations.
That was so intriguing to watch. You wonder, who built the first precision machine without precision. Well now I know. So cool!
No dust cover?
I'm looking to rescrape my freshly acquired cast iron surface plate. It has big dings and marks so it can be off quite a lot as of now.
Hi there, that sounds like a lot of work. You may want to consider having it reground before. Anyways, as long you are not aiming to replicate any NIST standards in you home garage, some lowspots are absolutetly ok. The plate I scraped here isn't perfect either. As long as you lnow your plate, that's totally fine for some work you do at home :)
I have the exact same issue, I bought a pair of cast iron surface plates and a camelback at an auction from a former technical college. The camelback was covered in a moderate layer of rust, clearly not having been used in a long while and not having been stored covered in oil, and those surface plates were especially dinged up. We have a lot of projects planned where we need precision references and thus we now have a couple side projects to acquire ultra precise (
@@pieterveenders9793 how about visiting someone who has a good big plate to do the job
@@pieterveenders9793 , Hey there. The issue is that the Whitworth three plate method requires three plates, as the name already indicates. It's also required to have the ability to rotate these plate by 90° in order for the plate to work. Robin Renzetti has a good video, explaining the problem using some kitchen sponges. Nevermind, if that's what you are aiming for, things will require a full regrind first, then copying everything off a known good plate, then Whitworth-scraping it using a third plate. Finally a lapping step may be required to achieve 5µm/1000mm.
Lovely work. Plenty good enough for 99.9% of any work on a steel surface plate.
Hey great job and I like the less amount of ink it makes the high very visible.
Just to add that the youtube channel "an engineers findings" also explored scraping steel and came up with some conclusions on scraping angles that worked (at least for him)
Thanks! Yeah found that after publishing the video! :D
Never done any of this (to speak of), but I found another guy who scraped steel. He suggested a totally different tool geometry, since the blade tend to dig in on steel. Yours look very conventional though, as used on cast Iron? Beautiful video though, I will watch it again!
Yes, i found that video as well, after I made this plate. He is completely right and his tool geometry is definitely better. I personally didn't experience the work hardening as a big thing. I am sure it reduced tool life a bit, but it wasn't unbearable. I also talked to a guy who does a lot of professional scraping, and he said he just runs with a 0 degree angle.
So yeah, it's a thing, but nothing to overthink actually.
Impressive endurance and craftsmanship. But i am not so decided about were the border between master endurance and a nerd is...
The distance between genius and insanity is only measured by success.
Just out of curiosity. Is there any reason not to use lapping tools to make it more flat? Like the way they use them on granite surface plates. Is it because of the difference in material or is there some other reason?
Commenting so I get notified if he replies
@@Chris-io2cs Good question! Yes, you can use a lapping plate to continue, and therefore make it even flatter. But the problem is, you need a lapping plate in the same or bigger size. If i had three plates of the same size, i could rub them against each other with lapping compound inbetween, which would increase the flatness.
I have an upcoming video where i will show that!
Hey what is the model of your Planam jacket ? It seem to be a pretty good fabric and quality assembled !
Hey,
sorry for the late response!
The model is called PLANAM BW 270
@@buildfromsketch8102 that’s the one I guessed ! Thank you. No worry for the delay ;)
Looks really cool, but what do you use the scraped plate for?
Thanks! :)
This is my daily shop plate that I use for lower precision measurements of small and medium parts, as well as a marking plate for scraping lines onto workpieces, for example to precisely mark holes I want to drill into stuff :)
I made it, so i don't risk damaging my granite plate or wearing it out.
But for really high precision measurements, I still use the granite plate from time to time.
Did you measure how much the drilling and tapping the side distorted the top surface? It looks like that area was low, relative to the highest parts, so it didn't affect thr result, but it would have been interesting.
No, I actually didn't measure that. I will do once I have have time for that. Good idea!
But as you already said, it wasn't high so it didn't affect the end result :)
Nice work , what cutting angle have you use on your carbide tip ? same as regular iron tip ? as steel is quite difficult to scrap .
Thanks! I used a +5 degree angle, which as I found out later is not ideal. You actually would aim for something like a -5 degree angle, as I found out from some very old literature. Nevermind, for me it still felt okay to be honest. I also talked to an oldschool scraping guy, and he used a 0 degree angle for steel, which seemed perfect for him personally.
So yeah, -5 degree by the book, but you can get away with other angles as well :)
What about installing hexagonal LED lighting as in in car detailing shops?
Can you automate the scraping with a gantry or robotic arm? I'm guessing flaws in machines might translate onto the plate, but I'm also wondering if one might slightly randomize the movements of the machine a bit, and calibrate each run manually with data input from your ink printing method.
I.e. don't automate the whole process, just help some of the monotony.
Well it's monotone, but it clears your mind :)
But automating it is hard, as you need a camera to detect the highspots. But that's next to impossible, as cameras and scraped surfaces are not working well together. But there is also no commercial application that would justify the automation...
Nicvto watch, thank for sharing
What i wanna know.. is what is that beautiful black colored block made of... It looks to be Stone. But i would love to know what it is
Granite
Great video. What is the radius on the carbide blade?
Thanks! 140, 90, 60 and 40mm radius :)
Very nice video. I enjoyed it very much. I have limited experience scraping. I've scraped some of the ways on my milling machines and lathe, as well as a 635mm steel straight edge. Scraping steel is much more difficult than cast iron. When you were scraping this steel plate, you probably took heavy, medium, and light scraping depths. What do you think those depths were? Thanks.
It's hard to quantify that, so i don't really have an answer to that question, sorry.
I looked up the scraper and it's only 300mm long. Isn't that too stiff ?
Well, it is stiff indeed. It worked out for me anyway. Here in Germany I actually have never really seen the more flexible scrapers. But I know they exist. I would like to test them out in the future :)
@@buildfromsketch8102 Thanks for the reply! What's the width of you scraper ?
@@martinnovak3949 It's 25mm. Altough I used a 30mm carbide blade in the beginning (it's sticking out quite a bit). 25mm seems to be a decent allround size, although it's too big for smaller things.
What if you used another flat scraped surface thats been hardened in some way to make the surface more flat?
38:00 I'd like to see someone mount a mirror to a gauge block and point a laser at it. can you measure it on the wall?
some wise guy said: if want something done well you have a few choices: 1# pay somebody to do it, #2 do it yourself, or #3 tell your kids not to do it. For nr 3 i do not trust my kids to get their yogurt in an 8" bowl so forget about something about microns... for pay someone to do it for you without you can check their work......... that is only a good plan if you have money to spend and you know what they do and you can check there a process. heads off his efforts and ill think he did a pretty good job
Thank you sir, highly appreciated!
Nice work!
Thx! :)
You may even earned Stefan Gotteswinter‘s respect with this one..😅
The godfather hasn't spoken yet, but maybe you are right and he is sitting in his basement right now thinking: "Well, this is a reasonable quality plate."
@@buildfromsketch8102 „Well, kind of ok-ish..“ 😁
Nice work btw and I am amazed by your dedication.
Is the semi circle from work hardening from the previous owner
What is this? Nile green?
It is interesting how were made rotary parts like spindles or shafts of the first machine tools in the world. I've been always thinking about it.
My question is: is it possible to get a cylindrical part using this method?
Hey there! Good question! Yes, you can also scrape round parts, for example bearings and spindles. The first machines were made from wood, with a primitive spindle that was made by hand, carving a round part out of wood. When steel was invented, they filed and scraped round parts by hand. They again were used for the first lathes. At a certain point it was possible to make more precise parts with the machine, than by hand. From this point on they used machines, and hand work together to build more and more precise machines, that again could build more precise machines. But all precision comes from a flat reference: the surface plate. You can use a surface plate as reference to build everythin you want. And you can make a surface plate by scraping it, using the whitworth three plate method.
@@buildfromsketch8102 it is interesting what methods did they use to make them
gr8 work here, you should continue on this plate with lapping, you will get sub micron if u did so, use a precision machinist level it can sense 1um curvatures but u will need very solid base or measure on bare ground, the dial measure you have used is not really for flatness it is for uniformity, imagine u r using the same setup on a perfect sphere you will still read zeros, also i never liked the neutral/positive rake angles on the blade on that video, it does a lot of biting, even on the video it shows that, not sure why the guy and everybody was happy with that, btw about the diamond wheels, how you control the run out on them? do they come with a convex curve so when you bolt them to the grinder they become flat? how that is addressed?
Hello there, thank you very much!
You do have some very good questions. You are right. I did talk about the measurement theory in the video as well: 34:49
The blade angle is something that somebody already suggeested to change to 0° or +5°. I will try this the next time when scraping steel.
The runout of the diamond disc is not controlled at all. It's just a cheap diamond wheel off ebay- mounted to a wooden plate. The runout is not critical.
@@buildfromsketch8102 got you, will wait for your experiment with a 0 or +5 rake coz it really did not work with me at all, thanks for your reply, keep up the good work!
@@GraphicManInnovations Thank you for your comment, your questions and your nice words! I will do a follow up video about this in some time!
There is a way of measuring two (any) surfaces to the precision of the dial gage, it is called reversal method. Can be done with 2 dimensional surfaces but works best with narrow beams:
Put two beams side by side and measure one agains another at equally spaced points.
Flip one and measure it from the underneath at the same points.
Take the slope out of the two series of measurements. Essentially make the points the deviation from the slope.
First beam is the average of the two measurement series.
Second is the half the diference of the two measurement series.
There is a video on youtube by Dan Gelbart: (Reversal method at the end)
ruclips.net/video/cwdoUjynpEk/видео.html
To avoid flipping one beam, 3 beams and a fixture to rest the the dial on the outside ones and measure the one in the center. After the 3 permutations of the center beam there is enough data to determine the 3 of them.
Hope I was clear enough.
Hey there, thanks for your comment!
Yes, you are right. The way Dan Gelbart is showing in the video, is a great way of doing this. Unfortunately I don't have a surface plate that is big enough to cross-check my hand scraped one. But I will revisit this surface plate in the future and do some more measurements on it! :)
Just found your channel and subscribed. Very nice work. Interesting video
Beautiful
I believe the important thing with local flatness is not having the feet of test instruments falling into holes- so test with a 10mm / 3 /8 foot is the standard way to go
The more standard way is to use an instrument holder with a flat lapped base or use a ``repeat-o-meter``... Also, using of gauge blocks is the norm with some measuring methods, if scraped surfaces are in question... The feet are more for general purpose high precision measuring, but for stuff such as this, lapped, instrument grade surfaces akin to gauge block ones are used... The instrument base may be machined as to provide a reduced surface, as in faking feet of larger size, but the end result is lapped... Either way, for madly flat surfaces, you dont even want feet, a large flat lapped surface is preferable, as it will indicate any shift due to any positive extreme anomaly however small on a larger area... Which is what large repeat-o-meters are practically designed for, just like the auto-collimators, but in a different way of doing it, its a bad comparison, but a somewhat adequate one...