Remember Pete I ask all my students to teach. Stefan asked me before posting it if I minded if he did it and I said I would be honored for him to pass on what I taught him. He knew how to scrape before, I just tweeked his info. lol. I hope someday we can have a reunion of all the kids, what a great time! Rich
My Father used to teach aprentices in the field. He#s what we'd call a Schlosser meister. In one of his classes he let his students scrape 100x100mm stainless steel plates. when his prime student was done, he put an oil film on both plates so a crane could test the strength. the 100x100mm plates could hold five tons of weight without letting go and at 5,4 tons the assembly ripped apart but the plates held together.
Good to see one of Richard King's deburring stones over there in Germany. They're a telltale sign that one's been through his class. He's going to be very proud to see his methods saved for posterity. Excellent job describing the process, as always!
Viele Danke, Stefan! All the guys here in the US are basking about their recent scraping class experiences, but no one's teaching. Now that I've seen it, I know I can do it. And endless thanks to Richard King for encouraging this!
Thank you for the great lesson. I've been trying to flatten out some mounting plates at work and am on my own for learning how to do it. Thank you again.
Thank you so much Stefan! Fascinating and well presented, detailed enough to start building skills but yet not scare the amateur. Looking forward to the next video.
I like how you demonstrated how to spread the ink/canode. Most others simple film what they are scraping and who is there but skip the small yet important details.
Hi Stefan, great work explaining the foundation stuff. The 'hinging' is often overlooked (guilty myself at times). One additional note I would add, is the amount of 'pressure' you place on the part when printing - it affects the print no end even when roughing - my advice would be avoid downward pressure and larger movements to minimize rocking motion over the master plate. Also consistent approach to print - hold same place and push /pull same amount each cycle. Just my experience having spent quite a few hours over the past few months scraping by hand - you tend to work out what sets your progress back when the scraping effort is higher :-). All the very best Mat
Trabalhei 55 anos nesses trabalhos de Rasqueamento nivelamento e alinhamengo geométricos de maquinas operatrizes de usinagem leve medias e pesadas.Hoje com tecnologias modernas diminuiram muito esses trabalho mais nunca deixara de ser usado porque os milésimos de mm sempre ficaram para serem raspados.Parabens pelo vídeo👍 .
Remember to teach the "Richard Kings 4 scraping rules" 1) scrape individual scrape marks 2) Scrape individual scrape marks 3) check the depth of the cut 4) Hinge the part. Stefan can explain what they mean. Amazing how what he shows looks so familiar....LOL He must have a photographic memory. LOL Rich
I was taught by an old machinist hot to scrape. That was thirty years ago. And I still have not forgotten what this man showed me. Scraping is a feel and art at the same time. Today most scrapers are just hacks, in a bad way.
Stefan, your work is certainly impressive, I always learn something from your videos but I would like to point out a few things. I’m certainly no expert, just an unknown apprentice with a passion to learn this trade, but my guidance on the subject has been from a couple of solid sources… Most of what I have learned comes from reading the Connelly Machine Tool Reconditioning book, cover to cover 😊, and from a career (40 plus years) scraping “master”- Harold, who I have recently been lucky enough to consult with. Couple of quick thoughts that may help you and the viewers that may be learning: 1) When spotting for the first time I’ve been applying much more bluing, it acts like a lubricant between the part and the surface plate when you have a few, very high, points that can have a negative impact on the plate as they can cause damage. Goal is always to remove bluing as you go, getting finer and finer resolution so that you are not mislead by excess bluing. 2) Pressure applied by the operator during the spotting can have a negative affect and skew readings, only enough sliding pressure (usually applied from the end), not downward, to move the part is required. The goal should be to never rock the part with downward pressure. 3) It’s very important to place the part on the plate, as flat as possible, with no chance to lower one corner early and impart false readings as a result. 4) When spotting, the motion required to impart the bluing is much less than what you have shown, sometimes as little as a ¼ inch would be sufficient. Once the surface gets better it requires even less movement to get a decent reading. This is a subject that very little is known about, most machines are no longer built with this technique, and it is awesome that you are spreading the bluing, I mean word 😊, as you have a good teaching skill that comes through in your videos. Please take this as my contribution to the subject, I don’t reach as many viewers as you do….Thanks for putting out these videos! Take Care
Stefan, I'm glad I found your channel after seeing your comment about the Drill Doctor. I enjoyed this video, nicely presented and you covered a lot of information. I've now subscribed and looking forward to part two and more. Nice meeting you.
Excellent instructional video. One observation, I would leave the ink roller on the back corner of the granite block when not in use to avoid picking up contaminants from your bench surface.
Thank you for another interesting video. I'd just like to point out that wellies are rubber boots, the pockets on the scraped surface are wells. Thanks again regards Matthew
Thank you very much for this video! Very educating! Unfortunatelly, Shaber worker is diyng profession along with ongoing deindustrialisation in my country. Great lathe and milling machines are going for scrap iron... Greetings from Russia.
"Stiction" is indeed the word you were looking for. I heard it most in reference to motorcycle forks, or stanchion tubes. The highly polished sliders in close contact with the fork seals required for oil retention, caused the undesirable side effect of "friction + sticking" = stiction. Your scraper topography as I'm sure you are aware is also the reason behind engine cylinder bores being roughened with a hone for oil retention.
Memories! Did scrape for about 3 years on high precision spirit levels and electronic inclination measurement tools. Different technic though. All by hand and the tool was drawn and not pushed. Also smaller tip.
Stefan's explanation of the metal-to-metal contact at around the 3-4 minute mark was enlightening to me. I have always had the impression that the numerous oil-filled pockets would feed oil *between* the metal surfaces and provide hydrodynamic lubrication with little or no metal-to-metal contact. I haven't watched much more than this at this point, so it may be covered further on, but I am confused as to how the oil can serve as a lubricant at all if the metal surfaces are in direct contact. Clearly, I have much to learn about fluid dynamics!!
Paul Dorman you have to squeeze all the oil out to get direct metal to metal contact. If the parts are moving, even just a bit, the oil on the high spots will be maintained by sticking to the metal.
Paul Dorman the film thickness of the oil is greater than the depth of the valleys. The surfaces are not actually in contact with each other, unless the film strength of the oil is exceeded (which takes a tremendous amount of load)
It would also seem to me that scraping allows you to control the pattern of the highs and lows. Every surface is going to have high spots and scraping ensures they are distributed evenly as opposed to potentially getting 2 "large " high spots binding on each other. Maybe?
Regarding hinging at time point 27:00 . The precise answer is not 33,3% but 1 - 1/√2 ≈ 29,29% this can be calculated by assuming a pivot point, adding up all forces acting on the pivot due to material to the right of the pivot, adding up all forces acting on the pivot due to material to the left of the pivot and then realizing both have to be equal (as they are already opposite, due to rotation). Otherwise there would be a net positive force on the pivot, causing the pivot to move, as there is absolutely nothing preventing the pivot from sliding (as we assumed perfect flat surfaces, so the force pushing down on a small area is only determined by the mass directly above said area, since the pivot is a point (i.e. has no area) the mass above the pivot is 0, therefore the force pushing down on the pivot is 0 as well. Looking at the formula for static friction we take an arbitrary friction coefficient µ multiplied with the downward force 0, resulting in 0 friction forces holding the pivot where it is).
Love this! I have an unusable jointer bed that I'm planning to flatten so this is really handy. I have bought a steel hand scraper, but I'm not sure how to sharpen it. But 60 degrees and -5 degrees sounds like a great starting point. Does it the steel scraper is flat (parallell)?
Back in the day we used old half round files which worked really well. And they did not cost anything as we got them from the scrap barrel. Using carbon steel actually works rather well. You are just always sharpening the tool.
Stefan, Thank you for this series. With everyone here in the states that have taken Richards classes you are the only one who has offered to teach us what you have learned!
hi stefan thank you for sharing all this information, around here if you even mention the word scraping ppl look at you funny, so i learned almost i know from books and watching nick mueller, tony and a few others, but what i have found to be an eye opener is the hinge points technique you described and the importance of it. . two questions if you have the time, how do you manage the cast iron dust/chips (if any) . take care. pete
Very interesting and well explained video. I would like to try scraping but I don't know a lot about it. I know they usually work with cast iron. Can i scrape steel ? Because i don't have cast iorn on hand and i would like to practise on some scrap material before doing some real parts.
Thank you so much for the transfer of this priceless knowledge, you have no idea how it's important to me, i will transfer your knowledge that i have mastered to younger precision fanatics who cross my path !
I know this is an old video Stefan but the hand scraper you made, what steel did you use for the body? I would think that mild steel at 4mm thickness would just bend and stay bent rather than have any spring in it at all.
If I'm to acquire some material to make a scraper handle like yours, what's preferred? I haven't worked with thin stock like this which wasn't aluminium so I'm a bit unsure whats the appropriate amount of springy @ 4mm
A rigid bench would reduce chatter. You do roughly the same thing flattening a wooden board with a plane, and a heavy bench with maybe floor bolts makes the board flatten and straighten much more quickly and accurately.
Nice! Thank you Stefan. Gonna do this to my lathe support. In the ends, it stucks due to unequal wear. Since it's called 'Part 1', can't find 'Part 2' 🤔
Where can I order carbide inserts and a holder? Is it Biax? I have been searching, but i cant find anything that looks like the holder and inserts like you have.
something I think is cool about scraping is that you don't actually need to start out with a master surface, given the right material you can make your own
Is there any practical way to scrape a machine without having a professional straight edge of any sort? I have a very old mill the knee moves up n down very easily on the upper part of its range, but the lower is rather hard (minimal wear there I assume) I would like to spend some time with this machine in the future trying to fix it up a lil bit (no intention of making it perfect to the 1/2 thou) its never going to be as nice as a modern Bridgeport, but would just like to make it a lil better. Any thoughts?
Raised corners seem to make sense. The metal block was probably squared up on a milling machine, whose table was probably a tiny bit more worn in the middle than on the edges, as these things go. So it basically describes a slightly concave path under the mill, no?
I just gave scraping a go an a piece of saw cut aluminum and a known to be bad surface plate. By hinging it on different spots of the surface plate and doing it twice for each spot after rotating the part 180 degrees I was able to surpass the flatness of my granite plate (it's way off from being flat)!
Remember Pete I ask all my students to teach. Stefan asked me before posting it if I minded if he did it and I said I would be honored for him to pass on what I taught him. He knew how to scrape before, I just tweeked his info. lol. I hope someday we can have a reunion of all the kids, what a great time! Rich
Thank you Richard . I am definitely going to make use of what I learn here .
One day I will take one of your classes!
Cheers Rich
excellent!
This Old Tony show me your TH-cam curriculum!! 😂
I like to play a game on TH-cam.....it’s called find This Old Tony.
Ur the coolest personality.
My Father used to teach aprentices in the field. He#s what we'd call a Schlosser meister. In one of his classes he let his students scrape 100x100mm stainless steel plates. when his prime student was done, he put an oil film on both plates so a crane could test the strength. the 100x100mm plates could hold five tons of weight without letting go and at 5,4 tons the assembly ripped apart but the plates held together.
Good to see one of Richard King's deburring stones over there in Germany. They're a telltale sign that one's been through his class. He's going to be very proud to see his methods saved for posterity. Excellent job describing the process, as always!
Well Done Stefan! I'm also one of Rich's students and it's great to see an instructional video on TH-cam now. Fantastic work.
Viele Danke, Stefan! All the guys here in the US are basking about their recent scraping class experiences, but no one's teaching. Now that I've seen it, I know I can do it. And endless thanks to Richard King for encouraging this!
Thank you for the great lesson. I've been trying to flatten out some mounting plates at work and am on my own for learning how to do it. Thank you again.
Thank you so much Stefan!
Fascinating and well presented, detailed enough to start building skills but yet not scare the amateur.
Looking forward to the next video.
I like how you demonstrated how to spread the ink/canode. Most others simple film what they are scraping and who is there but skip the small yet important details.
Stefan You have hit the sweet spot passing on this type of information . Thanks .
"Really old school" was to re-purpose worn out files for scraping, lots of grinding and resharpening, but it does work.
David Essam i just did this today! Had an old worn out file, turned it into a scrapper and it works somewhat well
you teach this art so well in very listenable manner, this is such an excellent presentation of valuable skill, thank-you from Australia
Absolutely love it! Thank you so much for this very technical training. Much appreciated
Great stuff! This type of craftsmanship is valuable! Love it! Cheers, Doug
Well done Stefan! I picked up a few pointers.
Best, Robin
Thanks Robin! I am always impressed by the Moore-style scraping you showed, thats something I hope to learn one day too.
stefan, that was a very good, comprehensive explanation and demonstration on the basics of hand scraping. Thank you!
I'm thoroughly impressed with both the utility of this finish and the technique to achieve it.
Excellent video. The words you were looking for are "rake angle" and "pivot point."
Excellent video. Thanks for taking time to make this series.
Hi Stefan, great work explaining the foundation stuff. The 'hinging' is often overlooked (guilty myself at times). One additional note I would add, is the amount of 'pressure' you place on the part when printing - it affects the print no end even when roughing - my advice would be avoid downward pressure and larger movements to minimize rocking motion over the master plate. Also consistent approach to print - hold same place and push /pull same amount each cycle. Just my experience having spent quite a few hours over the past few months scraping by hand - you tend to work out what sets your progress back when the scraping effort is higher :-). All the very best Mat
Excellent novice scraping video, Stefan, the best I have seen yet!
Trabalhei 55 anos nesses trabalhos de Rasqueamento nivelamento e alinhamengo geométricos de maquinas operatrizes de usinagem leve medias e pesadas.Hoje com tecnologias modernas diminuiram muito esses trabalho mais nunca deixara de ser usado porque os milésimos de mm sempre ficaram para serem raspados.Parabens pelo vídeo👍
.
Mr Pete is my shop teacher. This is exactly what i was looking for. Great content.
The black art of scraping............ now I know, thank you, superb craftsmanship, superb explanation skills.
The most informative scraping video on TH-cam (I havn't seen them all ;-). Excellent! Thank you.
Excellent lesson on scraping, thank you Stefan.
Remember to teach the "Richard Kings 4 scraping rules" 1) scrape individual scrape marks 2) Scrape individual scrape marks 3) check the depth of the cut 4) Hinge the part. Stefan can explain what they mean. Amazing how what he shows looks so familiar....LOL He must have a photographic memory. LOL Rich
I was taught by an old machinist hot to scrape. That was thirty years ago. And I still have not forgotten what this man showed me. Scraping is a feel and art at the same time. Today most scrapers are just hacks, in a bad way.
Stefan, your work is certainly impressive, I always learn something from your videos but I would like to point out a few things. I’m certainly no expert, just an unknown apprentice with a passion to learn this trade, but my guidance on the subject has been from a couple of solid sources… Most of what I have learned comes from reading the Connelly Machine Tool Reconditioning book, cover to cover 😊, and from a career (40 plus years) scraping “master”- Harold, who I have recently been lucky enough to consult with. Couple of quick thoughts that may help you and the viewers that may be learning: 1) When spotting for the first time I’ve been applying much more bluing, it acts like a lubricant between the part and the surface plate when you have a few, very high, points that can have a negative impact on the plate as they can cause damage. Goal is always to remove bluing as you go, getting finer and finer resolution so that you are not mislead by excess bluing. 2) Pressure applied by the operator during the spotting can have a negative affect and skew readings, only enough sliding pressure (usually applied from the end), not downward, to move the part is required. The goal should be to never rock the part with downward pressure. 3) It’s very important to place the part on the plate, as flat as possible, with no chance to lower one corner early and impart false readings as a result. 4) When spotting, the motion required to impart the bluing is much less than what you have shown, sometimes as little as a ¼ inch would be sufficient. Once the surface gets better it requires even less movement to get a decent reading. This is a subject that very little is known about, most machines are no longer built with this technique, and it is awesome that you are spreading the bluing, I mean word 😊, as you have a good teaching skill that comes through in your videos. Please take this as my contribution to the subject, I don’t reach as many viewers as you do….Thanks for putting out these videos! Take Care
very intricate lesson, cant wait for part 2, thank you
Its already there :)
Thanks for watching.
i massively enjoyed this video mate
Stefan, I'm glad I found your channel after seeing your comment about the Drill Doctor. I enjoyed this video, nicely presented and you covered a lot of information. I've now subscribed and looking forward to part two and more. Nice meeting you.
Awesome video! I dont know if i will never need to scrape something but i really enjoyed the video!
Excellent instructional video. One observation, I would leave the ink roller on the back corner of the granite block when not in use to avoid picking up contaminants from your bench surface.
Very informative, I always wondered how it was done
Thank you Stefan!
Many thanks for the excellent video, good luck and inspiration in the work!
Muchas gracias por compartir tu información.
Un saludo desde España.
Thank you for another interesting video. I'd just like to point out that wellies are rubber boots, the pockets on the scraped surface are wells. Thanks again regards Matthew
Большое спасибо. Очень доходчиво и обширно.
Great videos, thanks ! Scraping is fascinating ...
Thank you for the excellent explanation.
So true about the oil based dye - and no, I've not scraped flat surfaces, only the normal round cast bearings and cylinders.
I didn't realize that this is how it's done. Thanks
Thank you very much for this video! Very educating!
Unfortunatelly, Shaber worker is diyng profession along with ongoing deindustrialisation in my country. Great lathe and milling machines are going for scrap iron... Greetings from Russia.
"Stiction" is indeed the word you were looking for. I heard it most in reference to motorcycle forks, or stanchion tubes. The highly polished sliders in close contact with the fork seals required for oil retention, caused the undesirable side effect of "friction + sticking" = stiction. Your scraper topography as I'm sure you are aware is also the reason behind engine cylinder bores being roughened with a hone for oil retention.
Looked you up after watching Steve summers, excellent video, very good content for beginners like me. Thank you.
Interesting, clever, simple : Brilliant ( a susual !! ) !!
I love the labels on your drawers. You must get through a lot of Dymo tape with all those technical German words.
Thank you for sharing,great.
Memories! Did scrape for about 3 years on high precision spirit levels and electronic inclination measurement tools. Different technic though. All by hand and the tool was drawn and not pushed. Also smaller tip.
Did you work for Wyler?
@@StefanGotteswinter :-) yes! Moved then to KELLER AG für Druckmesstechnik before I went to the FH to study Electronic Engineering.
thank you for the info! that you labored for.
Stefan's explanation of the metal-to-metal contact at around the 3-4 minute mark was enlightening to me. I have always had the impression that the numerous oil-filled pockets would feed oil *between* the metal surfaces and provide hydrodynamic lubrication with little or no metal-to-metal contact. I haven't watched much more than this at this point, so it may be covered further on, but I am confused as to how the oil can serve as a lubricant at all if the metal surfaces are in direct contact. Clearly, I have much to learn about fluid dynamics!!
Paul Dorman you have to squeeze all the oil out to get direct metal to metal contact. If the parts are moving, even just a bit, the oil on the high spots will be maintained by sticking to the metal.
Paul Dorman the film thickness of the oil is greater than the depth of the valleys. The surfaces are not actually in contact with each other, unless the film strength of the oil is exceeded (which takes a tremendous amount of load)
I learned a lot.
Just brilliant Stefan! Please can you do a video on correcting dovetail geometry?
love how comprehensive is this tutorial
excellent explanation, thanks!!
It would also seem to me that scraping allows you to control the pattern of the highs and lows. Every surface is going to have high spots and scraping ensures they are distributed evenly as opposed to potentially getting 2 "large " high spots binding on each other. Maybe?
this is what i was looking for .thanks alot for sharing us this great lesson
I hope you like it! :)
Stefan Gotteswinter .when we following, you we,don't have to go to college ..sure i,like all,your jobs
Excelente información, saludos desde México
Thanks again Stefan!
thanks for sharing Stefan
Regarding hinging at time point 27:00 . The precise answer is not 33,3% but 1 - 1/√2 ≈ 29,29% this can be calculated by assuming a pivot point, adding up all forces acting on the pivot due to material to the right of the pivot, adding up all forces acting on the pivot due to material to the left of the pivot and then realizing both have to be equal (as they are already opposite, due to rotation). Otherwise there would be a net positive force on the pivot, causing the pivot to move, as there is absolutely nothing preventing the pivot from sliding (as we assumed perfect flat surfaces, so the force pushing down on a small area is only determined by the mass directly above said area, since the pivot is a point (i.e. has no area) the mass above the pivot is 0, therefore the force pushing down on the pivot is 0 as well. Looking at the formula for static friction we take an arbitrary friction coefficient µ multiplied with the downward force 0, resulting in 0 friction forces holding the pivot where it is).
Love this! I have an unusable jointer bed that I'm planning to flatten so this is really handy. I have bought a steel hand scraper, but I'm not sure how to sharpen it. But 60 degrees and -5 degrees sounds like a great starting point. Does it the steel scraper is flat (parallell)?
Back in the day we used old half round files which worked really well. And they did not cost anything as we got them from the scrap barrel. Using carbon steel actually works rather well. You are just always sharpening the tool.
Excellent video!!!
Good video to pass on to the younger generations. Many years ago we would make blades out of large machine hacksaw blades, hours spent scraping.👍
Awesome video!
thank you/ awesome job
Thank you, great job!
Stefan,
Thank you for this series. With everyone here in the states that have taken Richards classes you are the only one who has offered to teach us what you have learned!
good episode, I like it
Hi, great video!!
Have you measured how many micros, you take off after each pass?
What I’ve done, at times, for moving parts, is to surface grind, and then to scrape a wandering line for oil. It’s just maybe two tenths deep.
hi stefan thank you for sharing all this information, around here if you even mention the word scraping ppl look at you funny, so i learned almost i know from books and watching nick mueller, tony and a few others, but what i have found to be an eye opener is the hinge points technique you described and the importance of it. . two questions if you have the time, how do you manage the cast iron dust/chips (if any) . take care. pete
Very interesting and well explained video. I would like to try scraping but I don't know a lot about it. I know they usually work with cast iron. Can i scrape steel ? Because i don't have cast iorn on hand and i would like to practise on some scrap material before doing some real parts.
Thank you so much for the transfer of this priceless knowledge, you have no idea how it's important to me, i will transfer your knowledge that i have mastered to younger precision fanatics who cross my path !
I know this is an old video Stefan but the hand scraper you made, what steel did you use for the body? I would think that mild steel at 4mm thickness would just bend and stay bent rather than have any spring in it at all.
If I'm to acquire some material to make a scraper handle like yours, what's preferred? I haven't worked with thin stock like this which wasn't aluminium so I'm a bit unsure whats the appropriate amount of springy @ 4mm
A rigid bench would reduce chatter. You do roughly the same thing flattening a wooden board with a plane, and a heavy bench with maybe floor bolts makes the board flatten and straighten much more quickly and accurately.
Nice! Thank you Stefan. Gonna do this to my lathe support. In the ends, it stucks due to unequal wear. Since it's called 'Part 1', can't find 'Part 2' 🤔
great video thanks a lot.A question if we don t have a profecional marble . for hobby machine can use a glass or a common marble??'
Thank you for the vid. How thick material does one pass remove?
Obrigado, vídeo esclarecedor.
Sempre gostaria de saber qual era os ângulos e raio desta ferramenta.
What the hell did i just watch? 30+ minutes of a man scratch some steel? and now I cant wait to see part 2...
Where can I order carbide inserts and a holder? Is it Biax? I have been searching, but i cant find anything that looks like the holder and inserts like you have.
Awesome!
Thanks!
Great video! Needs more Prokofiev.
Nice Job
PPI writes cleaner than P/25.4mm. lol Great demo!
Stefan, I
something I think is cool about scraping is that you don't actually need to start out with a master surface, given the right material you can make your own
Yes - The three plate method. I would not want to do that ;)
Is there any practical way to scrape a machine without having a professional straight edge of any sort? I have a very old mill the knee moves up n down very easily on the upper part of its range, but the lower is rather hard (minimal wear there I assume) I would like to spend some time with this machine in the future trying to fix it up a lil bit (no intention of making it perfect to the 1/2 thou) its never going to be as nice as a modern Bridgeport, but would just like to make it a lil better. Any thoughts?
Raised corners seem to make sense. The metal block was probably squared up on a milling machine, whose table was probably a tiny bit more worn in the middle than on the edges, as these things go. So it basically describes a slightly concave path under the mill, no?
Hi Stefan, do you have any thoughts on using magnesium metal stock to make a straight edge? Can it be scraped?
Nice Well Done Thank You
I just gave scraping a go an a piece of saw cut aluminum and a known to be bad surface plate. By hinging it on different spots of the surface plate and doing it twice for each spot after rotating the part 180 degrees I was able to surpass the flatness of my granite plate (it's way off from being flat)!
Sketch1994 How did you test this?
Not that I want to do any scraping but interesting to watch. I was thinking, could a reciprocating saw be repurposed as a power scraper?
Thank you sir
Do you think a pice of cast aluminum tooling plate would be good to put a flat surface on to use as a strait edge?
"Either you are super careful. Which means you are lazy." Goes into the notebook of wisdom
Good job