Did Some Scraping Today...

[Andre]

Worked on a tiny "surface plate" this week to see how flat I could get a surface given what I know about scraping. Homemade scraper, even heat treated the blade myself. Used oil paint as a transfer blue and a comparator stand base as a reference plate.
Kinda wish I had a ten thou indicator....

[video=youtube;vJaAe0VMr4E]https://www.youtube.com/watch?v=vJaAe0VMr4E[/video]





1" Square



If you guys can see anything that that doesn't look right please let me know, I'm just trying to learn more about scraping so one day I can scrape my Bridgeport.

Thanks!

 

[tertiaryjim]

Like yourself, I'm learning scraping the hard way.
Your pattern and number of high spots looks really good to me.
What are you using for scraping tools? Picture please!

 

[Andre]

Like yourself, I'm learning scraping the hard way.
Your pattern and number of high spots looks really good to me.
What are you using for scraping tools? Picture please!

Thanks! I'm using a homemade scraper, pics later. Just a hour project to get this done. Rough, but I learned heat treating so that's a bonus.
Sorry I didn't get back to you earlier, didn't see your reply.

 

[tertiaryjim]

I started with a parting tool that I ground a large radius on one end and wrapped tape on the other. OUCH!
Have since made a couple holders for carbide but have yet to build a diamond lap. Need to refine my carbide holders some.
Seems it takes me forever to get anything completed. In part because I've too many projects going at once.
Look forward to seeing how you made your tools.

 

[Andre]

I started with a parting tool that I ground a large radius on one end and wrapped tape on the other. OUCH!
Have since made a couple holders for carbide but have yet to build a diamond lap. Need to refine my carbide holders some.
Seems it takes me forever to get anything completed. In part because I've too many projects going at once.
Look forward to seeing how you made your tools.

I wish I could help you, but I am new to this too and I don't want to mislead you. The best people you can ask are RC99 (practical machinist) Nick Muller, and Forrest Addy.

That being said,,,,,,You need a proper scraper for scraping. For me, I like it right up against my upper arm because I sit when is scrape and can do that. Holding a parting tool in your hand is just not ideal. You can make scrapers, go to woodcraft and puck up a scraper for woodturning. Basically a beefy metal scraper, just it has no spring to it. Not a big deal but it's easier to gouge your work. http://www.woodcraft.com/Product/2005238/10550/WoodRiver-1-Square-Nose-Scraper.aspx

FWIW, My tool had no spring to it either, I didn't have any problems.

If you would like to see me scrape a straightedge (making a tiny one now) I can take some video and time lapse it for you, it would explain a lot of things I can't put in text.

Here's some scraping videos for reference.

https://www.youtube.com/watch?v=nOJrhrne80s

https://www.youtube.com/watch?v=LkdkouWiDFs

https://www.youtube.com/watch?v=jx1D0buRCOY

https://www.youtube.com/watch?v=y2AUew5Evxc

https://www.youtube.com/watch?v=btybtxImkAE

https://www.youtube.com/user/MuellerNick/videos


Happy scraping!

 

[Andre]

Simple and ugly, but it worked great and stayed sharp.




Just a note, blade sits in a 1/16" recess, so it doesn't move when scraping. Did the rounded back recess with a flycutter. I apparently wasn't thinking to just do it straight, my mind made me to do it curved )






Hope you find this useful, tertiaryjim

 

[tertiaryjim]

This is my generation 2 scrapers.
The straight scraper, on right, sits in a 1/32" groove. The shank is from a filing cabinet file holder.

The left tool is more for decorative and flat surfaces such as angle plates. I put a lot of scratches in my surface with it until I got some diamond hones to dress it.
Then learned that it also works better if the head can rotate freely. Am considering a complete redesign of this one.

Thanks for the information. Have been watching the yutube vids.

 

[Andre]

This is my generation 2 scrapers.
The straight scraper, on right, sits in a 1/32" groove. The shank is from a filing cabinet file holder.

The left tool is more for decorative and flat surfaces such as angle plates. I put a lot of scratches in my surface with it until I got some diamond hones to dress it.
Then learned that it also works better if the head can rotate freely. Am considering a complete redesign of this one.View attachment 76316

Thanks for the information. Have been watching the yutube vids.

Glad I could help you, your pull scraper looks nice, I need to make one sometime.

How does your scraping look, do you have any pictures?

)

 

[John Hasler]

...And so did I. It's easier than I expected. I made a scraper out of a chisel: heated the tip red hot and dunked it in ATF. I know that made it brittle but it's scrap anyway, and so far it's working. Takes a nice edge on the oilstone which lasts about ten minutes. I found that putting a tiny relief on the corners reduced gouging. Magic Marker plus a tiny dab of oil works for me as spotting fluid.

My scraping looks pretty ugly compared to that of the pros, but the area with spots is getting larger and the spots are getting smaller and more numerous, so I must be doing something right.

 

[tertiaryjim]

Andre
Sorry to have taken so long. Got too many irons in the fire.
Recently made a couple new scraping tools ( version three ) and when you started this post I had scraped a fresh starting surface to test the new scrapers on.
This isnt much to look at and it's the first, though unfinished, effort with the new tools.
I was trying for very uniform scrape marks and just using the narrow edge.

The uniformity will decrease as I get closer to the desired high points. Still, I think it's a bit ugly.
Here is the surface blued.

The flash just had to pop.
Will finish this surface and then start over with a different pattern.

Have been looking at the scraping on the shaper I've been working on.
The areas where the scraped bearing surfaces aren't worn seem to show a greater area of contact than I had expected.
Perhaps because the clearances are so tight.
Have yet to blue any of it's surfaces but though theres so many other things that I should be doing, well just might have to check it a bit and soon.