Scraping basics - Scraping flat - Part 1

[@richardking8140]

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

[@goofypotatoe]

Thank you Richard . I am definitely going to make use of what I learn here .

[@stonecraft745]

One day I will take one of your classes!

[@Warpreacher]

Cheers Rich

[@ThisOldTony]

excellent!

[@Non-ya-business]

This Old Tony show me your KZbin curriculum!! 😂

[@SqueakerT]

I like to play a game on KZbin.....it’s called find This Old Tony.

[@anthonyrivers8395]

Ur the coolest personality.

[@jolioding_2253]

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.

[@NoelBarlau]

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!

[@PeteBrubaker]

Well Done Stefan! I'm also one of Rich's students and it's great to see an instructional video on KZbin now. Fantastic work.

[@PeopleAlreadyDidThis]

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!

[@geograph1000]

you teach this art so well in very listenable manner, this is such an excellent presentation of valuable skill, thank-you from Australia

[@CFABN267]

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.

[@Cpl.Cadaver]

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.

[@slartybartfarst9737]

The black art of scraping............ now I know, thank you, superb craftsmanship, superb explanation skills.

[@MrBigShotFancyPants]

Mr Pete is my shop teacher. This is exactly what i was looking for. Great content.

[@bejay69]

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.

[@josiahbaker7811]

I'm thoroughly impressed with both the utility of this finish and the technique to achieve it.

[@greybeard3759]

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.

[@ROBRENZ]

Well done Stefan! I picked up a few pointers. Best, Robin

[@StefanGotteswinter]

Thanks Robin! I am always impressed by the Moore-style scraping you showed, thats something I hope to learn one day too.

[@beardyface8492]

"Really old school" was to re-purpose worn out files for scraping, lots of grinding and resharpening, but it does work.

[@jasonmurawski5877]

David Essam i just did this today! Had an old worn out file, turned it into a scrapper and it works somewhat well

[@goofypotatoe]

Stefan You have hit the sweet spot passing on this type of information . Thanks .

[@peternichols9233]

Excellent video. The words you were looking for are "rake angle" and "pivot point."

[@blauesKopftuch]

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).

[@richardking8140]

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

[@victoryfirst2878]

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.

[@unknownapprentice625]

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

[@lookcreations]

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

[@jimzivny1554]

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.

[@josetoledo5620]

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👍 .

[@pauldorman]

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!!

[@RobertSzasz]

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.

[@matman7546]

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)

[@Ujeb08]

stefan, that was a very good, comprehensive explanation and demonstration on the basics of hand scraping. Thank you!

[@MatthewTinker-au-pont-blanc]

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

[@TomSaw_de]

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' 🤔

[@rjanzen3810]

"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.

[@oskarjohansson8313]

Awesome video! I dont know if i will never need to scrape something but i really enjoyed the video!

[@MegaCountach]

Great stuff! This type of craftsmanship is valuable! Love it! Cheers, Doug

[@TinkerJohn_W5CYF]

Excellent video. Thanks for taking time to make this series.

[@glennfelpel9785]

Absolutely love it! Thank you so much for this very technical training. Much appreciated

[@kokleongchong7397]

very intricate lesson, cant wait for part 2, thank you

[@StefanGotteswinter]

Its already there :) Thanks for watching.

[@SLRist]

I love the labels on your drawers. You must get through a lot of Dymo tape with all those technical German words.

[@DoRC]

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?

[@duobob]

Excellent novice scraping video, Stefan, the best I have seen yet!

[@solarpower09]

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.

[@josejaviercalatayud8338]

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??'

[@cmiimages]

Excellent lesson on scraping, thank you Stefan.

[@leifvejby8023]

So true about the oil based dye - and no, I've not scraped flat surfaces, only the normal round cast bearings and cylinders.

[@RoronoaZoro-yl2wi]

Can the sole of a hand planer be leveled using the three-plate method?

[@5150mkii]

Just brilliant Stefan! Please can you do a video on correcting dovetail geometry?

[@---Michael---]

Very informative, I always wondered how it was done Thank you Stefan!

[@thechipwelder1253]

Where can one buy a hand scraper and some high "spot liquid" in europe?

[@thechipwelder1253]

@Buro Dackel thank you very much for your answer!

[@arnljotseem8794]

The most informative scraping video on KZbin (I havn't seen them all ;-). Excellent! Thank you.

[@lucasandri5462]

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.

[@davidwright9139]

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.👍

[@victoryfirst2878]

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.

[@dummieall3150]

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?

[@gatekeeper84]

Where would the hinge be with a convex shaped surface as you demonstrate at 28:20? Near the center?

[@StefanGotteswinter]

Exactly, it would hinge from both sides pretty much in the center.

[@nineteen-sixty-nine9373]

How can hand scraping leave a true flat surface, It leaves oil channels?

[@robmckennie4203]

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

[@StefanGotteswinter]

Yes - The three plate method. I would not want to do that ;)

[@valanjo2001]

Obrigado, vídeo esclarecedor. Sempre gostaria de saber qual era os ângulos e raio desta ferramenta.

[@GraphicManInnovations]

love how comprehensive is this tutorial

[@Cancun771]

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?

[@jonbaker3728]

Can you scrape steel or is it limited to cast Iron??

[@StefanGotteswinter]

You can scrape almost every material - Cast iron, Ductile Iron, steel, brass, bronce, aluminium, many plastics, .. Some cut nicer than others, but the general principle stays the same.

[@thebrokenbone]

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

[@orvie29]

What was it you said i can find on ebay and disassemble and use the table as a surface plate?

[@StefanGotteswinter]

a coordinate measuring machine, short CMM. With shot electronics you can get them reasonable cheap.

[@ManushaWijekoon]

Any recommendations for the diamond wheels that can be used pleas?

[@trollmcclure1884]

no wonder it needs sharpening when cast iron is kinda iron carbide. I wonder what is the HRC hardness of good ole grey cast iron

[@dizzolve]

where do you find the basic hand scraper ....... to purchase say online

[@PrintreFiare]

can you use this tehniq for aluminium or softer materials?

[@melgross]

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.

[@josealcaraz1575]

Muchas gracias por compartir tu información. Un saludo desde España.

[@IvanGOrtolan]

Where did you find the Chinese import granite surface plate? I have been searching but cannot really find a reasonable priced one, not even including the shipping. I was planning on buying a 40x40x10 Grade 0+. I found a grade 0 in Germany for ~200

[@woozhi9218]

Whats the purpose of spacing each scrape would you do the same thing with step scraping wouldnt the spacing leave a high point ?

[@Sketch1994]

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)!

[@destro513]

Sketch1994 How did you test this?

[@Arckivio]

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?

[@craigtate5930]

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?

[@nowayjerk8064]

thanks for sharing !! but i don't think you covered the angle of the trout ? thanks again .

[@nowayjerk8064]

ill have to fin about that .

[@martinfaulkner2546]

Looked you up after watching Steve summers, excellent video, very good content for beginners like me. Thank you.

[@thetezz0001]

i massively enjoyed this video mate

[@bhnjhbjhbkgkkvhnhmbm]

Thank you for the vid. How thick material does one pass remove?

[@1873Winchester]

So since we scrape a surface for the high and low spots so oil can flow there.... I wonder if you could scrape a cast iron frying pan, well ofcourse you can, but would it do anything?

[@1873Winchester]

So you rescraped your lathe, I would dearly love to find a video of someone doing that, preferably in your detailed style.

[@samrodian919]

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.

[@ВиталикКурситов]

Большое спасибо. Очень доходчиво и обширно.

[@Bg_Anipar]

How repair broken bed?

[@aaronshed]

How do you get the scraper blades?

[@jw200]

Why nobody shows how to make that scraper? What materials to use etc.

[@James-fs4rn]

Hello, why do the initial scraping instead of checking the high spots first and rough them down? Seems unnecessary, but I don't know anything about scraping. Thanks

[@WojciechP915]

Are you using that continuously cast iron? We have a product called dura bar available in the states which is cast iron.

[@StefanGotteswinter]

Yes, that was continuous cast.

[@creamshop]

how do spell the stone you use after scraping ? , i heard '' ingus stone'' but can't find it

[@Sammus7t]

India stone, an aluminum oxide oil stone. Arkansas (novaculite) and silicon carbide stones are fine also.

[@creamshop]

@@Sammus7t Thank you !

[@creamshop]

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 !

[@zygmuntthecacaokakistocrat6589]

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.

[@xXJosafat07Xx]

is it possible to scrape something that is bigger than your flat plate?

[@stockstergates4061]

where can I get radius gauge? thanks

[@zumbazumba1]

i wonder if you could use old file for scraping blade.I heard that people used ball bearing shells for scraping before .Car leaf spring would be a good material for body,if you flat forge and maybe thin it down. Where can you buy good quality diamond grinding wheel? Im looking for conical bell type and flat one .any brand s you recommend?

[@StefanGotteswinter]

You will find yourself more sharpening then scraping ;)

[@StefanGotteswinter]

I had no problems with the chinese grinding wheels. There are a bunch of diamondwheels from russia sold on ebay, those are very nice and if you want "industrial quality", look for example at Winter, Tyrolit or Norton.

[@zumbazumba1]

Can you provide the link to the diamond disc that u used in part 2?Its generaly known that chinese produce a lot of junk ,and while product may look same, quality can vary extremly for factory to factory.

[@StefanGotteswinter]

Absolutely :) www.ebay.de/itm/150mm-Splitt-3000-THK-Diamant-Fest-Lappscheibe-schleifscheiben-polierscheibe-/201617380124?hash=item2ef155131c:g:brIAAOSw-KFXekG5

[@zumbazumba1]

Thnx stefan you are awesome!

[@I_Waste_Food]

Is there a way to find high spots with ink on a lathe bed or tailstock?

[@blickberg8404]

Hi Stefan, do you have any thoughts on using magnesium metal stock to make a straight edge? Can it be scraped?

[@waltersaunders7699]

Great thanks Stefan. at around 9 mins in, you mention buying a machine off ebay to cannibalise its master surface as a cheap way of getting one. What is the name of the machine? Thanks again

[@StefanGotteswinter]

A coordinate measuring machine, short CMM. They often show up with a broken or ancient control and go for reasonable little money.

[@fraggler12]

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

[@chrismoerlein]

How important is the variable speed feature for a power scraper?Would a fixed 1200 spm unit be acceptable?Thanks

[@StefanGotteswinter]

Relatively important - There are older BIax and Renz scrapers out there that have fixed speed, and you can run them slower with a dimmer-switch.

[@Deesdessessesder]

Was looking for the spelling of the brand of your scraper.. I'm glad it appeared somewhere on the page!

[@glenking3337]

Stephan. Ok im new to doing all of this. I live in Fairbanks, Alaska. Where things are hard to find and if found sometimes very expensive. For example an 8oz. Bottel of dykhem is $85.00 U.S. dollars. Ok that said for a diy dykhem do you think mixing an Ultramarine oil paint with say vasoline or balgbalm would suffice. Or is there a specific chemical factor for using prussian blue? Which the local craft store has none of.

[@marknelson7451]

Really enjoy your videos, Stefan, and your sense of humor. Somewhere in this series you mention two brands of manual scrapers, one of which you said was too stiff, and the second you said had the perfect flexibility. Can you list the brand of the good one?

[@marceloiannini8199]

I´m interested also in learning what brand of a good hand scrapper. I could get an Renz A-10, but would rather begin doing it by hand.

[@utente445588]

Grazie dove poter comprare quei prodotti e attrezzi?

[@fredrik.larsen]

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)?

[@feihongwoo3383]

Can I high carbon scrap low carbon steel

[@StefanGotteswinter]

Yes, it works, but its no fun.

[@graemewight2975]

For me i thought of it as like making valleys then knocking then knocking them down just like how u said it.

[@KPKyker]

What material would you suggest for the long flexible part of the scraper? Not sure if you mentioned it.

[@StefanGotteswinter]

Just mild steel, thats perfectly fine. All steels have the same E-Module, so even if you use toolsteel or springsteel, it will be just as springy.

[@lukerickert5203]

Nice videos much more clear than anything else out there (on youtube or otherwise:) While it is true that all steel has basically the same modulus that is only in the elastic region so if the steel is thin it is easy to exceed the yield stress and cause plastic deformation. I have made scrapers from a few different materials but found high quality and thin steel (say sections cut from a 3mm thick HSS saw blade) worked better than mild steel since you get more deformation before yield. I have some Biax blades as well but they are rather stiff in comparison and they are also crazy expensive :)