Shatter..

I am trying to scrape some A36 steel (or something similar) and compared to cast iron I get a lot of chatter marks.
I am sure a few people on here can inform me (and others) about the cause and remedies.

When I first started scraping I tried some hot rolled mild steel. Unless you have no choice it should be avoided. Possible but very difficult.

This is covered in depth in Richard's course material as well as suggestions from BIAX.
As far as I recall you change the scraping blade angle 0 or +5 on steel, but I might remember wrong.
I also believe it was the harder the material, the more positive angle, and vice versa, aluminium = large negative angle
as with relatively softer way liner material to avoid digging in

If you can edit the heading it is not Shatter, it's Chatter. It depends on if you are hand scraping or power scraping. Steel is a very difficult material to scrape either way. If I am hand scraping soft steel gibs by hand I use the same neg 5 degree blade I use for scraping cast iron. If i am power scraping it with a BIAX I use a 12 to 30 positive blade tip and the deg varies on how soft the material is. Also use short strokes and if your scraping by hand use the lift out at the end of the stroke. As the steel will burr up real bad, also use a slow motor RPM. Wear leather gloves when cleaning up as you will get slivers if your not careful. Also use a smooth cut file to debur it and a file card to clean the file before stoning it with a med grit Indian stone. Brush off the chips with a paint brush, Not so much a rag as it will catch and pull off threads of cloth.

I get chatter scraping steel, so don't feel bad. When scraping Iron I say scrape the checkerboard pattern x x x patterns, but in steel cute the part in different degrees or patterns and not just 90 deg's to eliminate the chatter. Thanks Jan for the plug....lol Rich

I wondered if if it was shatter or chatter. I can't edit the title, but edited inside the message.
I noticed the burrs and figured out how to fix that (like you describe).
I scraped in 0 / 45 / 90 / 135 directions after I noticed the chatter, and it did improve a little bit compared to only two directions.
I'll try lift out and short strokes, and do more random directions.
Thanks for the help Richard.

Panza please teach the rest of the members what you have learned and will learn with some pictures and discription . I wish more would follow up on what we show them with replies. Don't be shy to all of my students. Jan is the least shy of all of you and he is really making a impact on here and you tube. As Matt Critchley who also helps now and then told me at the Kalamazoo class he and one of his step brothers like Tadd and Jan should speak up more, please. Jan has a lot of info on You Tube. He just demo'd hand and power flaking. https://www.youtube.com/watch?v=DBIN56Z0JNk