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Increasing surface coverage and PPI

No offense to some of the other other them my students; Paolo Pete, Matt Lucky 7, Dec. But I taught how to scrape 20 ppi and 50 %. I taught them in 3 days using the crooked stones too. The way to get around crooked stones is to hold them in different directions or break them in half. Many dropped them...lol many of them learned to scrape 40 PPI too
Rich the fellow I pictured scraped his part in 2 days by hand. I started teaching him with the power scraper as I have found it shows how consistent stroke length is key to get rules 2 and 2.

I used to teach handscraping first but it's hard to get the same length stroke. I've taught over 40,000 people to scrape in 40 plus years. Next month I'm teaching Boeing techs and over the years have taught a 8 divisions of GM, CUMINS, TIMKEN, ETC. The photos you show the scrape marks are touching. Start on what you have and draw diagonal lines with a square and practice scraping diagonal rows # 1 & 2 rules to get the individual Scrape marks.
 

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Your part I convex too. Lay a gage block or parallel cross ways and hinge it. Also TC Tool and Stinberg are students. Plus I'm sure there are others. There is a YouTube show made by John Saunders of NYCCNC he filmed at Keith Ruckers shop where his parallel was convex and he showed checking it.
 
Hello everyone,

Sorry for the lack of answer, I was quite busy as I recently finished my engineering degree and I had a few job interviews lined up (and still have a couple more to do). I probably won't be able to scrape until this week-end but I'll send picture of my work asap.

Regarding the edge, I try to keep it as sharp as possible because I realised as you said that it becomes quite hard to scrape correctly with a dull insert.

Regarding the stoning, it was my belief that india stones aren't flat and I thought they wouldn't be suitable for deburring. Do you use your stones out of of the box or do you grind them first on a surface grinder ?
I do have a Norton india stone that I use to sharpen HSS tooling so I can use that but if a precision ground stone is required i'll have to wait to buy it as my finances won't allow for it 😀.

@Richard King I have been applying technique 1 and 2 but I think there is some confusion here (on my end). I have applied it during the point splitting technique (that led to the last picture I posted). As mentioned by everyone here, I probably need to go back to area scraping.

I am still trying to figure out when to switch from area scraping to finish scraping. Although I watched videos on youtube explaining it and I understand the theory, I still need to figure it out by actually practicing it if that makes any sense. I probably need to improve the consistancy in my technique also.

I do not have a copy of your DVD, but I would have liked to get one. Unfortunately I saw on your ebay store that you don't ship to Europe anymore. I would have also liked to attend a scraping class but the trip to the USA makes it too expensive for me right now. Bringing parts of my lathe or my shaper would also probably prove to be a challenge :D
Contact Biax Germany as they sell my DVD AND USB STICK. BIAX SPONSORS classes in Austria. You can look on YouTube under Richard King Scraping Biax and find a show Biax shot in Austria. My last class I taught there
The Latimer Brothers took over teaching my classes as the blood clot I got from flying long distances sucked. 2 Time studentand PM Member Pete is teaching in the UK and 5 time student and PM Member Jan Sverre Haugjord teaches in Scandinavia and has dozens of YouTube shows on scraping and rebuilding.
 








 
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