Getting ready for Richard's class in Pittston, PA this weekend

RWL

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I got this rough straight edge casting from Andy Lofquist, the proprietor of Metal Lathe Accessories in Pine Grove Mills, PA almost 30 years ago when we lived near each other. I milled all but one of the faces with my little Hardinge horizontal mill 30 years ago, and then life intervened. Now that I retired, I'm treating myself to Richard's scraping seminar and the straight edge will be my (or possibly one of my) project(s). I finally milled the second angled face today after 30 years. It was supposed to be 45º but it came out 46º. I'll see if that needs to be changed when I get to the scraping class. Pictures below.

01 Milling 45º angle on straight edge (Large).JPG 01a Milling 45º angle on straight edge (Large).JPG 02 Closeup of Milling 45º angle on straight edge (Large).JPG
 
Neat project. Congrats on the class,too. I'm jealous. Say hi to Richard for me.
 
Everything is just about ready ....

I cleared everything out of the main area of my shop and have the benches set up. Rich's flight comes in at 5:00 Friday and we will be ready for class at 8:00am Friday.

I can't wait.
 
I've been working on making some hand scrapers the past day or two. They finally came together today. The body is an 18" length of 3/16 x 1" mild steel that I bought at Lowes. The detachable scrapers are made to mimic a Biax blade. I made mine from 1/8 x 1" mild steel. The standard blades are 90 mm long (about 3.5" - I made mine 4") and the long blades are 150 mm long (about 6" long). Elsewhere on the net the slots in Biax scrapers are reported to be 0.209" wide and 17 mm long to the center of the radius (about 11/16"). I used a 7/32" end mill to make the slot and made it 13/16" long to the end of the cut. The Biax is reported to use 4.5mm screws. I used 10x32 socket head screws.

I used Stay-Silv white flux and silver solder strips. The strips came from a kit for repairing band saw blades which I bought at a yard sale, so I can't tell you what type of silver solder it was. Others have reported liking Harris 45% silver and Harris 56% silver solder. I polished one side of the 1/8 x 1/4 x 1" carbide insert on a diamond hone to remove any oxidation. The end of the holder had been freshly milled square. After applying a thin coat of flux to both pieces, I put the strip of silver solder on the holder and laid the carbide insert on top. I couldn't see when the silver solder melted, so I just heated it till it was red and let it cool. Once it was cool, I attached it to the scraper handle and laid into it. It held, so the technique must have been ok. I never silver soldered before. I suspect you're not supposed to heat it to red hot, but it was the only way I knew to be sure the solder had melted. After things cooled down, I put a 60 mm radius on one and a 90 mm radius on the other using a green carborundum wheel on my bench grinder. It left too many scratches to be a good scraping edge, but I wanted to have it roughed out before the class so that I wasn't roughing something out on somebody else's diamond wheel at the class. At the class tomorrow I'll use one of the Glendo grinders to really put the cutting edge on each of the scrapers. By the way, I got my radius by using a compass to draw circles with 60 and 90 mm radii on paper, then cutting them out and using them as templates to mark the ends of the carbide to know how to make the proper shape.

On the long holder, the tang is 2" long and about 3/8" wide. I added a 1/2 to 5/8 inch long piece of black iron pipe to the end of a 1-1/4"wooden dowel to keep the wood from splitting, then drilled a 3/8" hole for the tang. After that I hammered the handle on. I also drilled a 1/4" hole in the opposite end. Richard uses a cheap rubber sanding disk as a buffer when he pushes. I looked for one at the local flea market yesterday, but didn't spot any sanding disks. I had an old brass doorknob around, so I made an adapter to make it fit the back end of the scraper handle. I don't know how that's going to work out. I'll know tomorrow, but it will probably be better than just a 1-1/4" dowel sticking into my side / hip.


Photos below.

Most of the guys should be in Pittston already. I'm driving up tomorrow morning for the 8:00 start since it's only a 2 hour drive.

01 Set up to braze carbide tips on scrapers (Large).JPG 02 The white flux (Large).JPG 04 Scraper red hot (Large).JPG 06 Blade attached to handle, tang exposed without handle (Large).JPG 07 Finished scrapers - doorknob on one (Large).JPG 08 Moveable doorknob end (Large).JPG
 
Rich is in and we are set up. Only 2 of the guys made it up to the shop tonight .... I was hoping for more.
 
Nice job on those scrapers.

"Billy G"
 
Nice job on those scrapers.

"Billy G"

Thanks. They worked as well as the commercial ones. The 18" length was a bit long unless you're over 6 ft. Bill across the table from me and I both had made them 18" long and would make something shorter - probably 14" or 16". It's just a matter of cutting off a couple of inches and adding the threaded holes. The old doorknob at the end worked OK, particularly for bump scraping when you're nearing the max number of points you planned for the piece. The Canode blue and yellow worked well. Much easier to use than the old Prussian blue I had used 25+ years ago when I tried to teach myself out of books - I wasn't very successful. Don't waste your time making a scraper out of an old file, and use carbide.
 
Just some follow up on the angle on the straight edge. It doesn't matter what the angle of the straight edge is as long as it will fit in the dovetail to be examined / scraped. I learned that you don't scrape dovetails to a specific angle, just scrape them to make them mate each other.
 
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