Hi Tom, awesome video as always. I'm an aircraft engineer and started my career building jet engines for B707s one of the jobs I enjoyed was lapping the carbon seal face plates we had a 16" cast lap plate with a diamond slurry, straight line rubbing was the name of the game count to five then turn 90° and repeat as you can imagine a hard chrome faceplate took a while. Gee the hours I spent doing this haha good memories. There's something special about old school engineering that satisfied me and still does. It's an art.love the show you do. 🤠🇦🇺
Hi Tom! Maybe you find this useful : aluminum foil from food or hardware store (especially 30-40um) is pretty precise, thickness deviation is less than 1um for the whole roll. I use pieces of this foil as a "bib" for my surface plate while running a 3d-printed planetary lapping machine with abrasive powders on it. Just a tiny drop of viscous (220cSt) oil on a plate, decently spread on surface, holds foil sheet very strong. Surface plate is always clean, and you don't have to wipe it while changing abrasive number. Parts from this DIY lapping machine are almost as flat, as an optical flat, checked that recently.
That sounds very interesting. I have never heard of lapping done this way but it appears to have all the ingredients with the exception of grooves in the lapping plate. Film thickness would have to be controlled well to get good results. Thanks for the comment and suggestion. Cheers, Tom
Yes, grooves do a lot of good job with worn-out abrasive particles, foil method has this disadvantage. Classical flat-lapping machine uses interchangeable disks with grooves, but they are big, heavy and rather expensive. Thank you again for all your videos, it's a pleasure to watch!
I find this fascinating. Why, I don't know. I'll never need to do this. I'm not a machinist and at 70, it's not likely I will become one but I like your videos anyway. Nice work.
Tom's videos show us a side of machining we rarely see. Part of his job is to explore the best techniques for specialized machining jobs. From seeing the techniques he can share, it make us all a lot wiser.
Hi Tom, another great video! I just wanted to mention that you can further improve your accuracy and increase time between resurfacing your laps if you rotate them periodically in addition to rotating your part. An even more ideal option, especially for larger parts, is a heavy stand you can walk circles around while lapping.
Hi Tom. i always like watching your posts as it brings back memories & even though I've been retired for many years when I worked as A Toolmaker at a Government Factory & during The Vietnam War we made heaps of Fuse Timing Components for Both The Australian & American Services we had Vacuum Furnace which was very handy to Harden very small Punches & Dies as we could make them to Size Then harden them without any movement like what happened in The Salt Pots. Also we used The Diamonds on Lapping Plates.. We also Rolled Diamond Dust onto Small Mandrills for Jig Grinding very Small holes.
Thanks for an awesome video! Reminds me of a time when I was challenged years ago with putting together a lapping department for Pratt & Whitney bearing seal plates for main LPT shafts on JT8D, JT3D, GG4 + GG3 engines. The roughly 5" to 10" in. diam. thin plates were a repair. Had to grind off chrome, plate again, rotory grind .00005 flat and and lap. Tolerance .00002 and 5 micro. I used Speedfam and Lapmaster revolving tables w/ 9 to 5 micron slurry and a polish on the lapmaster with a 5 micron lexan film all under unconstrained free weight. The trickiest part I fond was cleanliness between the work and flat. I used a 12" flat. I used similar to drag method but dragged wipe from under work instead of work off wipe. Always that 'pinch' of fiber on the ending edge. I then resorted to moving the part away from last wipe contact to 'roll' any fiber out from under the part edge. Yes, I put work on flat with mirror under it with a 12"x2" thick circular flat which is cumbersome to move around. Clean sterile clean was the key to achieve 1 dispersed circular fringe without suction meaning it was simply hugging the flat which was flat within .000002. Glad I'm making chips again ;- ) Thanks and thumbs up!
Used to work at a machine shop that ground Steel mill rolls, and these rolls were ground to a 3 microinch finish. At that level of finish, the surface actually becomes dark, the linear scratches set up an interference pattern with visible light causing the reflections to cancel each other out.
Thank You Tom for another great video ! When I worked in the die shop 45 yrs back we would grind magnetic blocks to the chuck and first grind them in flat. Then we would grind the surface till it cleaned up, backing off the the mag chuck power we would turn the part 45 Deg and using the same height take a pass across the part. Then turn the part 45 Deg in the opposite direction and run across the part again at same height setting, we called this cross check grinning which would leave a cross check pattern but would remove many of the humps and bumps. Very Interesting Video & Helpful. Bill B
Hey Bill, That makes for pretty flat ground surfaces. There is another technique called spot grinding but its not for the faint of heart. Probably not a good thing to show in video form. Thanks for the comment. Cheers, Tom
Hi Tom, as I mentioned on on of Robin's recent videos, when watching both your channels, my head tends to explode getting my brain around these measurements. As you eluded to 'All that glitters is not gold'. Kindest regards. Joe.
Excellent video! Hoping you have a "Part 2" in the pipeline, as I'm very keen to see how you go about lapping for square and parallel, as that's something I need to do in my workshop soon :)
THANK YOU!!! I've been ranting for years that lapping for flatness and dimension is a skilled and finicky procedure. Rubbing two surfaces together with Clover valve grinding goo does not constitute precision lapping. My experience has been with production lapping like on a LapMaster. I have no experience with toolroom lapping or even the traditional apparatus used to do it so have been frustrated by my own ignorance in mentoring others. "That's wrong. I don't know what's right, but that ain't it." is unpursuasive to say the least and sure as hell doesn't lead to enlightenment. This video has been a revelation for me and I hope for others laboring under the blithe delusion of rubbing etc. I'd like to see more particularly lapping to dimension, roundness, gage making, lapping media, and more. Thanks again. Most educational.
Hey Forrest, You can count on lots more controlled rubbing. That little pile of heat treat I showed contains many examples of the types of fancy rubbing you mention. All the best, Tom
Hi Tom, another great video. When you clean sandpaper on a plate, wrap rare earth magnet in some plastic foil (even thicker plastic bag will work). Just gently swipe over sandpaper and it will collect all swarf. Unwrap magnet over the waiste bin, all swarf fall of, and magnet is clear. Of course it works only for steel/iron, and may not remove every tiny bit of swarf, but you do not get swarf and grit flying in the air around. Another thing is that loose abrasive grit will stay on top of sandpaper and continue to cut, so you get more from same sheet. Yes I know this is not lapping, but you can consider it "rough" preparation, and there are situations where this is just good enough (of course not for toolmakers instruments).
This is very interesting and illuminating, I appreciate the education in new precision terminology such as, dinguses, humpty bumptys, little du-du-dah-dits and little hick-ups, etc. As these terms are new to me, I beg your tolerance in my spelling, I’m sorta wingin’ it. On the serious side, this was extremely interesting and I look forward to more
"11 millionths - pretty flat" Love this channel man. As a hobby woodworker/welder/machinist I now have an idea as to how un-flat the backs of my chisels are.
Nicely done Tom, have you tried the kimwipe drag method of cleaning the part and the flat? I find it to be the fastest and most sure fire method. looking forward to seeing more on these parts. ATB, Robin
"Diamonds tend to settle out": worst James Bond movie ever. It's when he and the Bond girl have gained weight, their teenage kids are entitled brats, and their respective bosses belittle them at work.
Logical. Don't be a superspy. It's dangerous, you get tortured a lot, your ass gets whupped a lot, and and there is no way that you can top that, and I don't say that admiringly. It's better just to live an ordinary life, that way when you start living an ordinary life, it's not a disappointment.
Great video to come and rewatch sometimes. I just noticed you were using a raiser block on the surface grinder at 21:02 but I can't figure out why? The wheel goes down all the way to the chuck so, why would one choose to use a raiser block?
Euv lenses are 0.1nm figure and finish over the 600mm lens. I really liked your explanation and demo of the optical measurement of the surface. Scanning probe demo would also be good for me and perhaps your audience. Thanks again!!
Missed your detailed description of what you are doing, Hope everyone is well. You have obviously been quite busy,to bake any meatloaf. (i do enjoy it so very much) I Thank You Mr. Lipton
I got to spend some time many years ago with a master optician - he made large amplifier slabs for laser fusion research, a foot in diameter or more, an inch thick, and flat and parallel to 1/20 wave - and one of his tricks was to draw a few lines across a piece with a wax pencil before setting the reference flat on it. This was soft enough not to scratch anything, easy to remove, and gave the right spacing to easily see the fringes while bridging over any micro-dust that might be on the surface.
I've gound precision indexable carbide bits, and one of the first things to do is put them all in a plate with bit sized holes, and this would rotate off center against a bar. The plate with all the pieces will spin slowly on a 3 foot wide lapping table. The finished pieces were so flat they would stick together easily after wringing them together. I've also ground a lot of glass and plastic optical lenses. Many times, I've needed to grind what are called Plano surfaces on a lens blank
Thank you again. Please let this be the first of several. If you could, please give your thoughts on how the feedback from oil dye matching, solvent dye matching and monochromatic light gap referencing compaire to optical flat mapping.
Hi Carson, You got me on those. Don't know anything about dye matching or solvent dye matching. Sounds like a technique for measuring particulate size but I'm just guessing. Can you provide a link to the techniques you describe? Regards, Tom
oxtoolco Yeah, you might find my vocabulary off. I'm coming at this from the "how do I get this to fit tight" side, rather then the "how do I get this to index/reference repeatedly" side. Think high pressure matting surfaces. Dye matching is just like you do for a scraped surface, but instead of counting points, you dye the part, press it to a reference and look at how much of the dye didn't come off. Normally would use Prussian blue in oil, then in alcohol to show valleys as opposed to ridges. If you want to get crazy, use india ink or black it with soot and press. You print straight down and back up. No spinning or wiggling allowed. Less messy is using a long wave monochromatic light (the opposite of what you're doing) at a low angle to backlight a gap between the part and a plate or a straight edge. Sorry, I tried to find formalized reference material to link and came up empty. I appreciate your response and if you have read this far, you may find this interesting: www.techbriefs.com/component/content/article/1831
Makes me wonder if optical comparator prices jump every time you publish one of these videos. I think it's great that you are giving yourself a good challenge as well. Looking forward to seeing you soon, sir. Tom Z
Actually I didnt miss anything...I have seen all Tom's lapping and optical flat's videos. I was admiring the finish on the heated treated parts done in vacuum. I dont chase millionths but its interesting stuff
Super useful! Between your videos and those from Robin Renzetti, One of these days I'll get down to reconditioning these surface plates lying around neglected.
Thanks for the up load, your vids are helpful. Is there any way you can make a in depth video on optical flats? Like the set up and getting measurements, or understanding when it means to get into 2 lightbands or 3 lightbands. If not, do you of any other videos that might have this info?
Jeff Winkelman The interesting bit would be the difference heat treat makes to the ground surface. The previous videos didn't show anything that had been heat treated.
somebody else Partially. Surface finish is micro-scale deviations from an ideal surface. I wouldn't expect professionally heat treated parts to warp, but seeing if there were small-scale deviations as well as surface roughness.
That's the first time I'd ever heard the word 'dingus' (19:12). It is now officially my favourite word. 1. Something whose name is unknown or forgotten. 2. A person regarded as stupid. 3. Vulgar Slang The p*nis. I also learned a lot about lapping. Thanks for the super video
Interesting stuff Tom. You mention lapping soft materials is tricky, it seems like that would not be done that often? I'm working on a small job in OFHC Copper there is a "best effort" flatness spec on it...
Hi Bill, Soft copper is what got me started in lapping. Had a job for one micron over one inch that was .030 wide. Exit slit for a monochromater. The little diamond impregnated lap I showed is your best bet. Do it wet with something like lighter fluid that has a thin film and does not evaporate too quickly.
How did you make the fully charged diamond lap? I feel like that deserves a video. (Also I don't find any video about that on the tube, nor any article or forum post on the www)
I see some dovetails on some of those parts. That could get interesting? This is all very interesting what am I sayin' . The" give" in that sandpaper on the plate is what rounded those side's on that test piece like if you put some paper towels under sandpaper and rubbed say some 10 gauge on its edge you'd get a radius edge that really showed up on the optical thanks tom, mind stimulated ,many questions resolved
Thanks Tom, your lapping videos are always interesting as it's not something I've done much of, and then only with cast iron charged laps. How do you intend to determine perpendicularity to lapping tolerances? IIRC I don't think you have an autocollimator and that is way below indicator resolution.
Ahh but I do have an Autocollimator and electronic indicators that have microinch resolution. I should be able to inspect the right angles down to less than an arc second. We will find out together.
Oh you have an autocollimator? I didn't remember that, have you ever shown it in a video (I don't get to watch them all, and when I do I've often been working through the night, sorry if I forgot). You probably know it already, but one way to check perpendicularity with an AC is to put a known perpendicular surface in front, collimate on it, then slide it out the way. That will be accurate to the limit of your plate. Since your surface has 2 parallel surfaces there are of course other ways you no doubt know. Mirrors can be hard to get/expensive. I have successfully used old disk drive platters for first surface mirrors. They are double sided and very accurate, best of all free. Since they're double sided a mirror can be self-proved. I'm looking forward to the video you put up on the AC action. Thanks Tom
Very interested in perpendicularity in lapping video to come also! I haven't done any of that before, just some flat stuff. If there are any ways to do things on a low budget to lap/check, can you include them? I'd really like to start lapping some of my angle plates, 1-2-3 blocks, etc. to start doing this, but $ is tight.
Hello Tom. I am Asko from Finland. Thanks for great videos. I have 1916 manufactured Finnish made Karhula Sorvi, Sorvi means in English Lathe.. In spring She goes in my shop. She is very good conditition about age.. 210mm x 1500mm are dimensions. Maybee I take in spring some videos here. She,s weight is 1150 kg. Nice machine. Sorry my mistakes about writing. Try understand. All best for you and your Family from Finland.. T.Asko and Pimu, Pimu is my dog, 45kg.. Pimu means in english Pretty girl..
In my case, the die making created the OCD due to it's nature. Now I'm OCD on anything I work on, and I let the big pile of clothes in front of the hamper get noticed by the lady of the house's OCD. 😊
I have both ocd and add/hd. It's a wonderful attribute in the prototyping/small specialty parts business, but doesn't mesh very well if you're in a production environment.
@@keefjunior4061 thanks for saying that. I have been struggling for about 15 years to find a suitable work/job where my adhd and asberger/autism fit in. In other words: there is hope for me too.
Ouch!!! Cringing at the dry lapping... I've always done it wet, under moderate flowing water, to immediately wash away the SLAG and keep a "truer" surface. It's an extremely noticeable difference from dry, in both finish and accuracy..... I like to progressively go up to 2500 before polishing, it's painstaking but worth it. The lapping plate with diamond grit method you used is great! I always enjoy your videos, thanks for sharing!
Have you quantified your wet sanded surfaces for accuracy? In my experience adding water generally promotes greater edge rolling degradation than dry sanding with frequent cleanings. If you then polish to produce high luster you are smearing the material at the microscopic level and not producing accurate geometry. Lapping is all about the geometry not the finish.
Yeah i agree... It depends what your going for though, ultimate flatness or some level of compromise... some parts require polishing. In my experience wet has been far more predictable and edge rolling is largely due to technique and holding. Also, the way you introduce water... Avoiding floating of your part. Building a personal technique is crucial, eventually you can feel as the surface comes into flatness while your surfacing.
Kid, you have a lot to learn. You are just shining up your parts, nothing to do with accuracy. For now, you just "don't get it" (what's this all about with lapping, polishing, and so on). Bow down to the older folks. PS Having CNC doesn't make you "innovative".
wow classic ignorance... I might not be old but I'm 35 with 2 kids. I've worked in laser optics (spectral beam combining) and aviation components for years, i have the experience... Maybe you shouldn't be so quick to judge... Plus I said I agreed with what he said....I cringe at dry sanding like most do with nails on a chalk board... You have nothing pertinent to offer to the conversation, troll on somewhere else...
Having a CNC definitely does make you 100x more productive. Too stupid to learn a CAD program? Can't 3D model? Then fuck off gramps into the hell your generation brought US manufacturing into in the very early 90s. The only place left for you is machinery repair so enjoy it while you can still lift a steel bar into your manual lathe with worn out slideways and atrocious backlash. The young elite of CAD/CAM today are thousands times more valuable than an army of old bums who spent years in front of manual turret lathes and mills with all kinds of lame jigs. Sure there are a lot of young CNC bums having problems with some of the basics of metalworking but in the end they still spit out more complicated parts in more volume than the old generation who can't even work with a goddamn digital read out (my experience). Once an older slightly above average machinist meets a younger engineer who also has CAD/CNC experience they usually piss and shit their pants and can only talk about how in the older days he was the best in his team. Bow down to older folks my ass you US manufacturing destroyers!! To be good today you need to know metrology, basic physics of metal removal and machine stiffness, advanced design and great CAD skills - doing well optimized CNC programs will only come naturally to you. In my experience the elite of the elite are about 40 years old college educated engineers - the education and time they had to soak up makes them not only the best machine designers (semiconductor, sattelites, particle physics detectors) but remarkable machinists who can do their own CNC programs that on certain projects can be in the tolerance of nanometers. It's not an rarity to meet today a PhD person who not only designs parts, electronics, writes code, does simulations and also is a goddamn crazy good CNC dude. Just a week ago I've met this guy who already in college worked on nanometer tolerance projects and now works for ASML - pretty much the top semiconductor company of the last 10 years and the tips and tricks he shared were out of this world.
Hi Tom, firstly great informative videos, you have a gift for explaining things... I'm particularly interested in trying to achieve greater precision with my tooling around in the shed. I'm interested in the pair of little honing stones you often use to clean up the machine table etc... What sort of grit are they, how do you keep look after them and maintain flatness? Cheers Paul I
So why use copper? That's a really soft metal and wouldn't it become "unflat" really fast? Also when lapping do you need to worry about taking off that tempering purple finish? How deep does that finish go into the metal?
Next time, when you get to showing an example like at the time frame of 15:30.... can you show how much a line drawn in ink from a "SHARPIE" marker will change the flatness.. maybe a dot of ink, and or a ink line ... just to give an idea of how thick the ink is and how much it may throw off the glass if at all?
Hello love your videos! Would it be possible to do a video on how to achieve parallel surfaces while lapping? I think that would be really interesting content as I have not seen any video covering the subject.
Newbie here to lapping. It would be helpful if you explain where to get that glass and what kind of glass to use as well as what lighting to use. Thanks!
It's called an optical flat. It is some kind of quartz glass... not sure. The important thing is the lightsource, it should be a monochromatic light. A source which outputs exactly one colour of known wavelength of light.
"Just because it's shiny doesn't means it's flat" - Nicest thing anyone has said to me. My shiny bald head thanks you!
Lol. At least won't need an optical flat to find the belly button.
Hi Tom, awesome video as always. I'm an aircraft engineer and started my career building jet engines for B707s one of the jobs I enjoyed was lapping the carbon seal face plates we had a 16" cast lap plate with a diamond slurry, straight line rubbing was the name of the game count to five then turn 90° and repeat as you can imagine a hard chrome faceplate took a while. Gee the hours I spent doing this haha good memories. There's something special about old school engineering that satisfied me and still does. It's an art.love the show you do. 🤠🇦🇺
Hi Tom! Maybe you find this useful : aluminum foil from food or hardware store (especially 30-40um) is pretty precise, thickness deviation is less than 1um for the whole roll. I use pieces of this foil as a "bib" for my surface plate while running a 3d-printed planetary lapping machine with abrasive powders on it. Just a tiny drop of viscous (220cSt) oil on a plate, decently spread on surface, holds foil sheet very strong. Surface plate is always clean, and you don't have to wipe it while changing abrasive number. Parts from this DIY lapping machine are almost as flat, as an optical flat, checked that recently.
Инженер that sounds like a great setup, could you do a video on it?
That sounds very interesting. I have never heard of lapping done this way but it appears to have all the ingredients with the exception of grooves in the lapping plate. Film thickness would have to be controlled well to get good results. Thanks for the comment and suggestion.
Cheers,
Tom
Yes, grooves do a lot of good job with worn-out abrasive particles, foil method has this disadvantage. Classical flat-lapping machine uses interchangeable disks with grooves, but they are big, heavy and rather expensive. Thank you again for all your videos, it's a pleasure to watch!
Why not, will try to do a short clip.. If you agree to deal with my horrible "russian english")
Ай промис ту дил виз ё хоррибл рашн инглиш, соу вэйтинг фо ё видео игэрли.
I find this fascinating. Why, I don't know. I'll never need to do this. I'm not a machinist and at 70, it's not likely I will become one but I like your videos anyway. Nice work.
Tom's videos show us a side of machining we rarely see. Part of his job is to explore the best techniques for specialized machining jobs. From seeing the techniques he can share, it make us all a lot wiser.
"I'm not a robot."
You know who says that? Robots, that's who.
I know who the robot is. Dale Derry. Guy doesn't blink at all in most of his videos.
hey, i passed the turing test on only my third try!
You missed your Calling. You are a great Teacher, Now i finally understand the process, I might need to know that someday. Thank You.
Hi Tom, another great video! I just wanted to mention that you can further improve your accuracy and increase time between resurfacing your laps if you rotate them periodically in addition to rotating your part. An even more ideal option, especially for larger parts, is a heavy stand you can walk circles around while lapping.
I do rotate the laps as I use them. Just didn't happen to show in the video. Good point as a reminder.
Great video. The elegance of producing premium surfaces with this method is just beautiful.
Hi Tom.
i always like watching your posts as it brings back memories & even though I've been retired for many years when I worked as A Toolmaker at a Government Factory & during The Vietnam War we made heaps of Fuse Timing Components for Both The Australian & American Services we had Vacuum Furnace which was very handy to Harden very small Punches & Dies as we could make them to Size Then harden them without any movement like what happened in The Salt Pots.
Also we used The Diamonds on Lapping Plates.. We also Rolled Diamond Dust onto Small Mandrills for Jig Grinding very Small holes.
I learned a lot from the lap series and the light and lens measurement technique is amazing
Thanks for an awesome video! Reminds me of a time when I was challenged years ago with putting together a lapping department for Pratt & Whitney bearing seal plates for main LPT shafts on JT8D, JT3D, GG4 + GG3 engines. The roughly 5" to 10" in. diam. thin plates were a repair. Had to grind off chrome, plate again, rotory grind .00005 flat and and lap. Tolerance .00002 and 5 micro. I used Speedfam and Lapmaster revolving tables w/ 9 to 5 micron slurry and a polish on the lapmaster with a 5 micron lexan film all under unconstrained free weight. The trickiest part I fond was cleanliness between the work and flat. I used a 12" flat. I used similar to drag method but dragged wipe from under work instead of work off wipe. Always that 'pinch' of fiber on the ending edge. I then resorted to moving the part away from last wipe contact to 'roll' any fiber out from under the part edge. Yes, I put work on flat with mirror under it with a 12"x2" thick circular flat which is cumbersome to move around. Clean sterile clean was the key to achieve 1 dispersed circular fringe without suction meaning it was simply hugging the flat which was flat within .000002. Glad I'm making chips again ;- ) Thanks and thumbs up!
Your're a really good teacher, thanks for the video!
Great video.
You're definitely the next level and beyond.
Very interesting Technology and explanation.
Thanks for sharing.
Take care, Ed.
Used to work at a machine shop that ground Steel mill rolls, and these rolls were ground to a 3 microinch finish. At that level of finish, the surface actually becomes dark, the linear scratches set up an interference pattern with visible light causing the reflections to cancel each other out.
Thank You Tom for another great video ! When I worked in the die shop 45 yrs back we would grind magnetic blocks to the chuck and first grind them in flat. Then we would grind the surface till it cleaned up, backing off the the mag chuck power we would turn the part 45 Deg and using the same height take a pass across the part. Then turn the part 45 Deg in the opposite direction and run across the part again at same height setting, we called this cross check grinning which would leave a cross check pattern but would remove many of the humps and bumps. Very Interesting Video & Helpful. Bill B
Hey Bill,
That makes for pretty flat ground surfaces. There is another technique called spot grinding but its not for the faint of heart. Probably not a good thing to show in video form. Thanks for the comment.
Cheers,
Tom
That sounds pretty similar to what Don Baily shows in this video. ruclips.net/video/CsTbWAu0k-o/видео.html
Thats a deep understanding a love for knowledge to master this art. And a shop load of tools. Much respect
One of your best. Well, organized and presented. Keep up the good work.
that is incredible educational video ..every minute of it is fore price of gold .
thank you for shearing
Thanks for all your time with the video, just got a lapping job coming up and can use all the techniques I can get.
Hi Tom, as I mentioned on on of Robin's recent videos, when watching both your channels, my head tends to explode getting my brain around these measurements. As you eluded to 'All that glitters is not gold'. Kindest regards. Joe.
Excellent video! Hoping you have a "Part 2" in the pipeline, as I'm very keen to see how you go about lapping for square and parallel, as that's something I need to do in my workshop soon :)
And I thought you were going to talk about cats drinking milk and not spilling any, You learn something new every day.
This is not the world I work in but it is cool to see and learn about none the less. :-)
the same here :) have asses to a milling machine and Lathe both Manuel in a Makerspace also others hand tools, but only a pin-welder no TIG or MIG
THANK YOU!!! I've been ranting for years that lapping for flatness and dimension is a skilled and finicky procedure. Rubbing two surfaces together with Clover valve grinding goo does not constitute precision lapping. My experience has been with production lapping like on a LapMaster. I have no experience with toolroom lapping or even the traditional apparatus used to do it so have been frustrated by my own ignorance in mentoring others. "That's wrong. I don't know what's right, but that ain't it." is unpursuasive to say the least and sure as hell doesn't lead to enlightenment.
This video has been a revelation for me and I hope for others laboring under the blithe delusion of rubbing etc. I'd like to see more particularly lapping to dimension, roundness, gage making, lapping media, and more.
Thanks again. Most educational.
Hey Forrest,
You can count on lots more controlled rubbing. That little pile of heat treat I showed contains many examples of the types of fancy rubbing you mention.
All the best,
Tom
This channel is fascinating! Thank you for posting for us!
FINALLY BACK TO NORMAL TOM!!!! THANK GOD!
Man, I'm so jealous you can do cool shit as an exercise. You are doing something right man. Beautiful work.
That tool steel is such a nice colour after heat treating. Great stuff!
Hi Tom, another great video.
When you clean sandpaper on a plate, wrap rare earth magnet in some plastic foil (even thicker plastic bag will work). Just gently swipe over sandpaper and it will collect all swarf. Unwrap magnet over the waiste bin, all swarf fall of, and magnet is clear.
Of course it works only for steel/iron, and may not remove every tiny bit of swarf, but you do not get swarf and grit flying in the air around.
Another thing is that loose abrasive grit will stay on top of sandpaper and continue to cut, so you get more from same sheet.
Yes I know this is not lapping, but you can consider it "rough" preparation, and there are situations where this is just good enough (of course not for toolmakers instruments).
This is very interesting and illuminating, I appreciate the education in new precision terminology such as, dinguses, humpty bumptys, little du-du-dah-dits and little hick-ups, etc. As these terms are new to me, I beg your tolerance in my spelling, I’m sorta wingin’ it. On the serious side, this was extremely interesting and I look forward to more
I can't believe you have made over a hundred lapping videos. Good man, keep em coming. :-)
"11 millionths - pretty flat" Love this channel man. As a hobby woodworker/welder/machinist I now have an idea as to how un-flat the backs of my chisels are.
Awesome content as always. Thanks for sharing. The epoxy embedded Renzetti stones look great!
looking forward to learning how you maintain the geometry during lapping. thanks for another great vid Tom.
Nicely done Tom, have you tried the kimwipe drag method of cleaning the part and the flat? I find it to be the fastest and most sure fire method. looking forward to seeing more on these parts.
ATB, Robin
Final cleaning of industrial laser lenses is done by just dragging the lens paper, as well. I think it's a common practice with optics in general?
Yes it is indeed.... the ol' drop'n drag. (never dry!)
love your vids, I learn something every time I watch them
Thank you. You’re an exceptional teacher.
Thank you for this most informative tutorial! I learned a lot about lapping.
Thanks for the very informative video.
I dont know what im watching and have no expertise at all.. but I know this is damn interesting... Keep up the great work!
"Diamonds tend to settle out": worst James Bond movie ever. It's when he and the Bond girl have gained weight, their teenage kids are entitled brats, and their respective bosses belittle them at work.
Logical. Don't be a superspy. It's dangerous, you get tortured a lot, your ass gets whupped a lot, and and there is no way that you can top that, and I don't say that admiringly. It's better just to live an ordinary life, that way when you start living an ordinary life, it's not a disappointment.
This video was so captivating. I appreciate it! I cant wait to get into some high accuracy lapping sometime in my future :)
Great video to come and rewatch sometimes. I just noticed you were using a raiser block on the surface grinder at 21:02 but I can't figure out why? The wheel goes down all the way to the chuck so, why would one choose to use a raiser block?
This is just fantastic. Great talent!
Very good info as always. Still working to get my plates flat, but it's also good to see what is possible, and how it is achieved. Thanks Tom! 👍
That was a fantastic video
Nice video Tom, thanks for sharing 👍
Euv lenses are 0.1nm figure and finish over the 600mm lens. I really liked your explanation and demo of the optical measurement of the surface. Scanning probe demo would also be good for me and perhaps your audience. Thanks again!!
Missed your detailed description of what you are doing, Hope everyone is well. You have obviously been quite busy,to bake any meatloaf. (i do enjoy it so very much) I Thank You Mr. Lipton
I got to spend some time many years ago with a master optician - he made large amplifier slabs for laser fusion research, a foot in diameter or more, an inch thick, and flat and parallel to 1/20 wave - and one of his tricks was to draw a few lines across a piece with a wax pencil before setting the reference flat on it. This was soft enough not to scratch anything, easy to remove, and gave the right spacing to easily see the fringes while bridging over any micro-dust that might be on the surface.
I've gound precision indexable carbide bits, and one of the first things to do is put them all in a plate with bit sized holes, and this would rotate off center against a bar.
The plate with all the pieces will spin slowly on a 3 foot wide lapping table.
The finished pieces were so flat they would stick together easily after wringing them together.
I've also ground a lot of glass and plastic optical lenses.
Many times, I've needed to grind what are called Plano surfaces on a lens blank
Excellent teaching!!!
Thank you again. Please let this be the first of several. If you could, please give your thoughts on how the feedback from oil dye matching, solvent dye matching and monochromatic light gap referencing compaire to optical flat mapping.
Hi Carson,
You got me on those. Don't know anything about dye matching or solvent dye matching. Sounds like a technique for measuring particulate size but I'm just guessing. Can you provide a link to the techniques you describe?
Regards,
Tom
oxtoolco Yeah, you might find my vocabulary off. I'm coming at this from the "how do I get this to fit tight" side, rather then the "how do I get this to index/reference repeatedly" side. Think high pressure matting surfaces.
Dye matching is just like you do for a scraped surface, but instead of counting points, you dye the part, press it to a reference and look at how much of the dye didn't come off. Normally would use Prussian blue in oil, then in alcohol to show valleys as opposed to ridges. If you want to get crazy, use india ink or black it with soot and press. You print straight down and back up. No spinning or wiggling allowed. Less messy is using a long wave monochromatic light (the opposite of what you're doing) at a low angle to backlight a gap between the part and a plate or a straight edge.
Sorry, I tried to find formalized reference material to link and came up empty. I appreciate your response and if you have read this far, you may find this interesting:
www.techbriefs.com/component/content/article/1831
Thanks Tom
Enjoyed the content. Very Zen for me.
I need to make surface plates for lapping the bottom of my handmade infill wooden hand planes 😁 great work
very interesting stuff, as always we learn a lot.
Makes me wonder if optical comparator prices jump every time you publish one of these videos. I think it's great that you are giving yourself a good challenge as well. Looking forward to seeing you soon, sir.
Tom Z
Hope you make a new video soon... it's a pure joy to watch you do your thing... ☺
Great video. I feel like I just got a practical introductory education in lapping flat surfaces.
Nothing, not even the world, is "flat" :). Good demonstration, thanks.
can we get 'just because it's shiny doesn't mean it's flat' tshirts ?
That immediately made me think of a glitter covered T shirt over a pair of boobs, but that's just the way I think most of the time.
Re-runs! I watched the first showings.
2020 calling. Where's muh shirt? :)
Great video Tom. Keep them coming. Matt C.
nice. thank you. why copper for the lap surface
Nice looking parts Tom
It's not about the look. You completely missed the message.
Actually I didnt miss anything...I have seen all Tom's lapping and optical flat's videos. I was admiring the finish on the heated treated parts done in vacuum. I dont chase millionths but its interesting stuff
Super useful! Between your videos and those from Robin Renzetti, One of these days I'll get down to reconditioning these surface plates lying around neglected.
Thanks for the up load, your vids are helpful. Is there any way you can make a in depth video on optical flats? Like the set up and getting measurements, or understanding when it means to get into 2 lightbands or 3 lightbands. If not, do you of any other videos that might have this info?
It would be nice to see a comparison of a freshly ground surface both pre- and post- heat treat with the lapped surface under the optical flat.
Paul Ste. Marie I think he may have in his other video where he laps steel plates. I think.
Jeff Winkelman The interesting bit would be the difference heat treat makes to the ground surface. The previous videos didn't show anything that had been heat treated.
Heat treat affects different with different materials and shape of the parts. Some are pretty stable, others will flex like crazy.
I wonder if he means how the surface finish (not part geometry) is affected by the heat treatment?
somebody else Partially. Surface finish is micro-scale deviations from an ideal surface. I wouldn't expect professionally heat treated parts to warp, but seeing if there were small-scale deviations as well as surface roughness.
When I was at Vickers BEA system's we had a rotating table. Pour on liquid grind paste. Place in the piece leave for x amount of time.
GREAT VIDEO !!!
That's the first time I'd ever heard the word 'dingus' (19:12). It is now officially my favourite word.
1. Something whose name is unknown or forgotten.
2. A person regarded as stupid.
3. Vulgar Slang The p*nis.
I also learned a lot about lapping. Thanks for the super video
Interesting. Good job
No more figure of eight!! Thanks Tom this totally makes sense and I always hated it. Genuine thanks.
„I have a much bigger one, but it tends to squeeze all the air out.“ 😂
Wow thank you for this video Tom.
Thank you for sharing! It would have been interesting to see you inspect it with an dial indicator before and after lapping.
Interesting stuff Tom. You mention lapping soft materials is tricky, it seems like that would not be done that often? I'm working on a small job in OFHC Copper there is a "best effort" flatness spec on it...
Hi Bill,
Soft copper is what got me started in lapping. Had a job for one micron over one inch that was .030 wide. Exit slit for a monochromater. The little diamond impregnated lap I showed is your best bet. Do it wet with something like lighter fluid that has a thin film and does not evaporate too quickly.
oxtoolco Will give that a look, my part is .250 dia with .016 hole in the center. They want no CS edge on the hole. Thanks again.
I’m spoiled having access to a Balatron wheel balancer. It won’t get you gage block level finish but you can get pretty darn close though
Susssh! I've been lurking around trying to snag one.
How did you make the fully charged diamond lap? I feel like that deserves a video. (Also I don't find any video about that on the tube, nor any article or forum post on the www)
I see some dovetails on some of those parts. That could get interesting? This is all very interesting what am I sayin' . The" give" in that sandpaper on the plate is what rounded those side's on that test piece like if you put some paper towels under sandpaper and rubbed say some 10 gauge on its edge you'd get a radius edge that really showed up on the optical thanks tom, mind stimulated ,many questions resolved
Thanks Tom, your lapping videos are always interesting as it's not something I've done much of, and then only with cast iron charged laps.
How do you intend to determine perpendicularity to lapping tolerances? IIRC I don't think you have an autocollimator and that is way below indicator resolution.
Ahh but I do have an Autocollimator and electronic indicators that have microinch resolution. I should be able to inspect the right angles down to less than an arc second. We will find out together.
Oh you have an autocollimator? I didn't remember that, have you ever shown it in a video (I don't get to watch them all, and when I do I've often been working through the night, sorry if I forgot).
You probably know it already, but one way to check perpendicularity with an AC is to put a known perpendicular surface in front, collimate on it, then slide it out the way. That will be accurate to the limit of your plate. Since your surface has 2 parallel surfaces there are of course other ways you no doubt know.
Mirrors can be hard to get/expensive. I have successfully used old disk drive platters for first surface mirrors. They are double sided and very accurate, best of all free. Since they're double sided a mirror can be self-proved.
I'm looking forward to the video you put up on the AC action. Thanks Tom
Very interested in perpendicularity in lapping video to come also! I haven't done any of that before, just some flat stuff. If there are any ways to do things on a low budget to lap/check, can you include them? I'd really like to start lapping some of my angle plates, 1-2-3 blocks, etc. to start doing this, but $ is tight.
Is the shop made autocollimator project on the schedule yet? :)
11 millionths-
Tom: "Meh. Its Pretty flat" 😁
Great video! Keep it up!
Hello Tom. I am Asko from Finland. Thanks for great videos. I have 1916 manufactured Finnish made Karhula Sorvi, Sorvi means in English Lathe.. In spring She goes in my shop. She is very good conditition about age.. 210mm x 1500mm are dimensions. Maybee I take in spring some videos here. She,s weight is 1150 kg. Nice machine. Sorry my mistakes about writing. Try understand. All best for you and your Family from Finland.. T.Asko and Pimu, Pimu is my dog, 45kg.. Pimu means in english Pretty girl..
It appears that being extreme OCD is a benefit if you are precision machinist.
afn29129 David You do know that extremely OCD people insist that it's "CDO" - must be in alphabetical order don't you know.
In my case, the die making created the OCD due to it's nature. Now I'm OCD on anything I work on, and I let the big pile of clothes in front of the hamper get noticed by the lady of the house's OCD. 😊
I have both ocd and add/hd. It's a wonderful attribute in the prototyping/small specialty parts business, but doesn't mesh very well if you're in a production environment.
@@keefjunior4061
Too true.
@@keefjunior4061 thanks for saying that. I have been struggling for about 15 years to find a suitable work/job where my adhd and asberger/autism fit in. In other words: there is hope for me too.
Yes. Monday is my Sunday, and I get Precision lapping instructions for breakfast.
Ouch!!! Cringing at the dry lapping... I've always done it wet, under moderate flowing water, to immediately wash away the SLAG and keep a "truer" surface. It's an extremely noticeable difference from dry, in both finish and accuracy..... I like to progressively go up to 2500 before polishing, it's painstaking but worth it. The lapping plate with diamond grit method you used is great!
I always enjoy your videos, thanks for sharing!
Have you quantified your wet sanded surfaces for accuracy? In my experience adding water generally promotes greater edge rolling degradation than dry sanding with frequent cleanings. If you then polish to produce high luster you are smearing the material at the microscopic level and not producing accurate geometry. Lapping is all about the geometry not the finish.
Yeah i agree... It depends what your going for though, ultimate flatness or some level of compromise... some parts require polishing. In my experience wet has been far more predictable and edge rolling is largely due to technique and holding. Also, the way you introduce water... Avoiding floating of your part. Building a personal technique is crucial, eventually you can feel as the surface comes into flatness while your surfacing.
Kid, you have a lot to learn. You are just shining up your parts, nothing to do with accuracy. For now, you just "don't get it" (what's this all about with lapping, polishing, and so on). Bow down to the older folks.
PS
Having CNC doesn't make you "innovative".
wow classic ignorance... I might not be old but I'm 35 with 2 kids. I've worked in laser optics (spectral beam combining) and aviation components for years, i have the experience... Maybe you shouldn't be so quick to judge... Plus I said I agreed with what he said....I cringe at dry sanding like most do with nails on a chalk board... You have nothing pertinent to offer to the conversation, troll on somewhere else...
Having a CNC definitely does make you 100x more productive. Too stupid to learn a CAD program? Can't 3D model? Then fuck off gramps into the hell your generation brought US manufacturing into in the very early 90s. The only place left for you is machinery repair so enjoy it while you can still lift a steel bar into your manual lathe with worn out slideways and atrocious backlash. The young elite of CAD/CAM today are thousands times more valuable than an army of old bums who spent years in front of manual turret lathes and mills with all kinds of lame jigs.
Sure there are a lot of young CNC bums having problems with some of the basics of metalworking but in the end they still spit out more complicated parts in more volume than the old generation who can't even work with a goddamn digital read out (my experience).
Once an older slightly above average machinist meets a younger engineer who also has CAD/CNC experience they usually piss and shit their pants and can only talk about how in the older days he was the best in his team.
Bow down to older folks my ass you US manufacturing destroyers!! To be good today you need to know metrology, basic physics of metal removal and machine stiffness, advanced design and great CAD skills - doing well optimized CNC programs will only come naturally to you. In my experience the elite of the elite are about 40 years old college educated engineers - the education and time they had to soak up makes them not only the best machine designers (semiconductor, sattelites, particle physics detectors) but remarkable machinists who can do their own CNC programs that on certain projects can be in the tolerance of nanometers. It's not an rarity to meet today a PhD person who not only designs parts, electronics, writes code, does simulations and also is a goddamn crazy good CNC dude. Just a week ago I've met this guy who already in college worked on nanometer tolerance projects and now works for ASML - pretty much the top semiconductor company of the last 10 years and the tips and tricks he shared were out of this world.
Very interesting to see what flatness really is. 🙂🙂🙂
I would love to see what a hand scraped surface looks like under one of these optical blocks
Always interesting. I'm in Brians camp tho....tractor stuff! ;-)
Hi Tom, firstly great informative videos, you have a gift for explaining things...
I'm particularly interested in trying to achieve greater precision with my tooling around in the shed. I'm interested in the pair of little honing stones you often use to clean up the machine table etc... What sort of grit are they, how do you keep look after them and maintain flatness?
Cheers Paul
I
Hey Tom, thanks for the vid! Do you have any learnings from lapping for squareness?
So why use copper? That's a really soft metal and wouldn't it become "unflat" really fast? Also when lapping do you need to worry about taking off that tempering purple finish? How deep does that finish go into the metal?
What material are the lapping discs made of?
Super good Tom! Thanks for this :)
I fell down the rabbit hole, where did the time go. :D Thanks :)
Next time, when you get to showing an example like at the time frame of 15:30.... can you show how much a line drawn in ink from a "SHARPIE" marker will change the flatness.. maybe a dot of ink, and or a ink line ... just to give an idea of how thick the ink is and how much it may throw off the glass if at all?
Tom did a video a while ago where he measured the thickness of the ink of different markers. It's massive (by his standards anyway)
Here it is : ruclips.net/video/46DBNUfhATo/видео.html
I bet he uses sharpie marks to shim up parts on his surface grinder...
Hello love your videos! Would it be possible to do a video on how to achieve parallel surfaces while lapping? I think that would be really interesting content as I have not seen any video covering the subject.
thanks for the video ,, good lesson...
Nice job.
Newbie here to lapping. It would be helpful if you explain where to get that glass and what kind of glass to use as well as what lighting to use. Thanks!
It's called an optical flat. It is some kind of quartz glass... not sure. The important thing is the lightsource, it should be a monochromatic light. A source which outputs exactly one colour of known wavelength of light.