Clarification on scraper sharpening

All you need is a piece of micrograin carbide, say perhaps 1" wide, 3/8 to 1/2" long, and 2mm, 3/32", or even 1/8" (3mm) thick, C2 grade seems to hold up well and chips less. Different sizes and tip radii work with different types of work and also depend on user preference. Blanks are available from places like MSC, and purpose made Sandvik Coromant scraper blades are available on eBay, though the prices have really increased (just looked, !!!) in the last few years. Great deals are still out there, though, with some searching. It is not rocket science, but some guidelines should be followed to have a good initial experience... PM me if you want help in deciding on equipment. I am a rookie as well, but I do understand what works...
 
Thanks for replying Bob. I have the information on the geometry from biax for both the radii and the rake angle. I just picked up a diamond sharpening setup (accu finish) at an auction. All I need to do is fab the blades out of cold roll and get some carbide blanks. The sandvik inserts appear to be $50 each and the biax ones are about the same. Are the blanks from msc of a comparable quality? Richard King has shown guys in his classes the difference between chinese carbide and the good stuff. I would like to avoid the frustration of using poor material without having to spend a fortune. Am I kidding myself thinking I can make my own blades with cabide from Msc? Any other sources that anyone can recommend? Thank you for your insight.
 
MSC, KBC Tools, etc are fine for brazing your own scraper blades. I purchased a 10 pack of thick carbide square blanks from ebay for less than $10 with shipping. These measure roughly 3/16" thick and are about 7/8" square. This tool is used to scrape large flat areas.

For smaller areas like dovetails, I use the KBC carbide or even a cheap brazed lathe tool mounted on a screwdriver shank.

Scraper Carbide blank.jpg


Matt
 
Hi Matt,
I really liked your video on your scraper sharpening, and also the nice setup you made for your surface grinder. I am doing the same, and bought an inexpensive diamond flaring cup wheel direct from China, 100 mm OD, 32 thick, 20 bore, and 10 wide abrasive, 600 grit ($11.41 for the wheel and $0.71 for shipping!). This will only be used to sharpen/hone the blade at low speed, not to form it initially. I have a carbide grinder for doing that. My question is: did you have to open up the hole in the wheel to 1-1/4" for the wheel adapter? If so, I would be interested in the setup you used for that. It is a non-trivial setup challenge, at least for me so far, after thinking about it for a few days. I would like to be able to set it up based on the O.D. of the abrasive, not on the existing hole, which might well be off center. This is a cheap wheel, and I want to get the hole in the center as well as the mounting face parallel with the abrasive face. I messed around with several setup options using my 8" rotary table, but could not get anything robust enough to chance cutting it with a boring bar. I was using a piece of Delrin with a center hole that would press down on the angled walls and four toe clamps to push the Delrin plate down toward the table, and trying to block it radially with four short bolts and flat washers in t-nuts. The t-slots were over full and the whole setup was just not solid enough. I also do not want to tear up the abrasive with the mounting. I can work harder on that approach, but thought I would stand back and rethink the setup. I did not come up with any good ideas for using my lathe for this, the slots of my faceplate begin too far out radially on the plate (D1-4 mount.)

I am not interested in a $100 setup to machine my $12 wheel...

Anyone else want to chime in as well? This is what I bought:
http://www.ebay.com/itm/100mm-Diamo...326645?hash=item3f6b4fb9b5:g:uOsAAOSwOyJX4KyP
s-l1600.jpg
 
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I recently purchased some sandvick scraper blades off eBay for a few dollars each. You don't kneed 10 of them, I have the original 5 I was issued as an apprentice and they all remain serviceable. The crazy prices in the list posted above are not reflective of what a scraper needs or costs. I have a Sandvick blade holder that is nearly 40 years old and is all I ever used. The Biax is a horrible tool and produces a rough finish. Scraping like file work is meant to be precision work carried out in a workman like manner. It is not a surface grinder or milling machine. Small amounts of material are removed with care. Get a photo of the screw clamp blade holders and make one to fit the blades you can find.

86 the file handle as the tool is designed to be pushed by the hip, not the hand. Make some large ended wood handles of several lengths and for less than $30 you have a scraper. No need for an ink roller, glue. Piece of suede to a wood block, served me fine for 35 years. Permatex bluing works just fine at a few bucks a tube.


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