Questions about scrapers

If you cannot afford Richard's class, find a mentor who has learned from Richard or another journeyman scraper hand. Richard tells us to spread the knowledge. Vet the mentor as carefully as possible. Again, it is very easy to damage a machine further by clueless scraping. Reconditioning machines is first about getting the geometry and flatness of the surfaces correct, and only near the end getting more points and a beautiful finish. Lots of 'so called' scraping is only done to make it look pretty.
 
Benmychree, I am working with the file type for now, but will be looking for a low cost way to get a better scraper.

Bob, would you know of anyone willing to help me out? It would be great to just have someone to bounce conversation off of to start.

The things I am doing right now are purely to slightly flatten out a few parts that should be flat. I have a large surface plate to reference so that shouldn't be too bad. I don't have any way of working on the ways so forget that.
 
I would come over and help you, but it is quite a drive...

Perhaps someone reading this thread who lives in your area will offer to help you get started with scraping...

Flat things are the easiest to scrape, blue them up on the surface plate and then scrape wherever there is blue showing. But the devil is in the details. It is easy to make the plate concave or convex, and convex is more difficult to notice and deal with. Also, scraping using techniques you make up will only make it more difficult to learn how to do it correctly later. I have mentors, helpers, experts, and master machinists I can call on for help, simply by being willing to ask for it, and return the favor by being willing to help others as best as I can as well. Quite simply, ask for help. That is what I did with scraping about 5 years ago. I contacted Ulma Doctor and asked for help learning to scrape. And he helped me. We have been friends since then.

Being a hobby machinist does not mean you also need to be a self declared hermit! This forum is a great source of help, and getting knowledgable help in person is even better. Ask!
 
Here are some pics of the scrapers I've made and acquired in the couple yrs I've been trying to learn the skills of scraping
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The one in the center is one I made to hold the sandvik style blades. The one on the right I got from a flea market find its a Anderson style has a brazed carbide piece. The one on the left I just made for getting in dovetails and such. You can find the sandvik blades on eBay. Problem is they can be expensive gotta look. I've read of people putting a different radius on each side giving you four options. And grinding both sides like the picture gives you two cutting edges just flip it over. These are at a neg. 5 degrees which if read is about the go to. Different materials different angles. You'll need some diamond files, laps or green wheel for sharpening the carbide. Some spotting dyes I use Canode dye which is easy to clean up another is Dykem which is a oil base and is a bear to clean. You'll look like a smurf for days. It's alittle challenging you need to just do it and try and under stand what's going on with each pass of the scraper. It's easy to see the difference in you tubers the skilled ones show the results through measurements. Check out Stephan G I'd butcher his last name but he's a German fella with a wealth of knowledge about scraping. He's done richard kings class and is outstanding at what he does. Another is nick maybe mueller on utube he has some about scraping a compound quite thorough with some good tips.
 
The inserts from Sandvik come sharpened on both sides, but a person may want to change the radius, usually to something of a smaller radius for finer spotting, also I keep a insert that is ground nearly flat for scraping rust off way surfaces. The best thing for sharpening is the Glendo lapping machine, next in line a carbide grinder with a diamond wheel, then the green wheel. When I started scraping, about 56 years ago, I started out using Dykem (Prussian) blue, then after doing some reading in the Machine Tool Reconditioning book, started using red lead in oil, kept in a paper snuff box; you mix it well with a minimum amount of oil, press it into the box, and the box wicks the excess oil, for use put in a few drops of oil and rub it in with the fingers and transfer it to the marking tool and rub it into the surface, and piece of grit or forigen matter can be felt and rubbed off. I have the Canode that Rich K. gave me and it sure is a lot easier to clean off than any other medium, and I like using the yellow for background on the article being scraped; it is applied very thinly and mostly rubbed off, it makes the blue medium stand out much more clearly when rubbed off the marking tool.
 
Bob is right in general, but I'll 'scrape' my archives to find the really good ones. I really believe that you can get the basics from a good video or 2, and then you can better utilize formal training if that time comes.

If I can fit it in soon, I'll post my 'best of' in this thread...

My scraping mentor missed some of the great advice from some oif the videos I've viewed on the 'tube!
 
Looking good! Where did you get the straight edge casting?
 
It is a Gary Martin, from Martin Pattern and Mold I believe is the name.
 
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