burrless scraper - Woodworking Talk

cathardo · 02-23-2009, 10:16 AM

I have recently started to try to use a cabinet scraper for the first time. I have flattened and honed the edge using my “scary sharp” papers, and a homemade jig to keep the edge perpendicular. I cannot seem to achieve any burr at all. The scraper produces a smooth finish but only very very fine dust, not shavings. I have noticed that I cannot scratch the face of the scraper with the tang of my mill file. Is it possible the scraper is tempered too hard? It’s a Swedish made Bango brand card scraper. any advice would be welcome as I'd love to learn to use this tool.

Rob · 02-23-2009, 10:23 AM

I don't see anything in your post about rolling a burr on the edge with a rod of some sort of hardened steel. This creates the burr. After the honing and flattening, you roll the edge at an angle. You should be able to feel the burr with your fingernail.
If you are doing this step but still don't feel the burr, you may not be rolling it hard enough.
Just a thought...

cathardo · 02-23-2009, 11:45 AM

Yes, I have attempted to "roll" a burr on the edge. I have viewed numerous web-videos on how a burr is to be first rolled on the face, then turned to create the cutting edge (hope that makes sense) seems kind of simple to at least get something. I have NOT purchased a store built burnisher, wanting to first learn the basics before investing more monies. I have tried to use both the shank of a 5/16 drill bit, and a fully hardened and polished (2 min at bright red with quench) 0-6 tool steel rod, and adding a drop of oil as I try to roll a burr.

My process to date is first flatten and hone the scraper to a polished edge (to 1000 grit) holding the scraper in my jig which should produce a good 90 deg. I have also done a light polish on the face to make sure I removed any manufacturing edge curvature. I then lay the scraper flat on my bench, and scrap with my rod, holding it just a few degrees off parallel to the face, pushing down with maybe 5-10 pounds force. 15 to 20 strokes. I then stand the scraper up, and attempt to roll any burr that would have been created with my rod (but to small to see or feel).

At this point I’m not concerned to try to get a very uniform burr, that will come with time and practice, just any burr would move me on my way.

Rob · 02-23-2009, 02:06 PM

I never had much luck with holding the scraper flat and using a burnisher to roll the burr. I always put the scraper in my jig, in a vise and have to use two hands to get enough pressure. All these years I've been keeping the burnisher at around a 30* angle and make 4-5 passes on each side. I don't go back and do anything to the top...just each side.
I can get 15 minutes or so with the two edges before I have to go back and burnish again.
Try it that way and see what you come up with.
Good luck!

joesdad · 02-23-2009, 07:03 PM

I lay a ten inch flat file on the bench with the handle towards me, hold the scraper edge down firmly to the file and pull back four or five times till I feel the file cutting. Done. I don't create a burr and I can shave ribbons until I need to do it again. Flip the scraper over and do the other side too of course, if you have soft hands you may want to put a glove on or something.

firehawkmph · 02-23-2009, 10:25 PM

Cat,
Get a burnishing tool, they're cheap. Put the scraper in a vice to hold it upright and draw the burnisher across the edge with both hands applying moderate downward pressure. Hold the burnisher about 15-20 degrees off level. After about a dozen strokes, you should be able to feel the burr with the edge of your fingernail. I create a burr on the two opposite edges of my scrapers that are square or rectangular in shape. Then I don't have to stop for awhile. When you are using your scraper, are you flexing it somewhat to create a very slight arc in it while pushing or pulling it?
Mike Hawkins

cathardo · 02-24-2009, 12:41 PM

As I work at a large industrial complex, I brought the scraper in and examined it under a good powerful microscope. Amazing what you find.

As I said, my technique has been to lay the card down flat, and try to raise a burr along the top (thin) edge, then to stand the card up, and roll the burr (if there was one). In looking in microscope it appears that I have compressed the very edge, without raising a burr (or destroying the burr when I try to roll it).

I just viewed my umpteenth internet video on sharpening a card scraper, one by Chris Schwarz of popular woodworking. In watching this it appears that the burr is actually created when burnishing the card along the thin edge (stand card in vice and burnish thin edge) also as Mike Hawkins suggests. I had been under the assumption that the burr was created by burnishing the card laying down, and then the burr was “turned” by running the burnishing tool along the edge. At any rate, I’ll give this technique a try tonight.

raskgle · 02-24-2009, 06:42 PM

I use a shop belt sander. staying on the meddle under the belt. For blades i use 6 inch jointer blades have no problum getting a bur and i carry one in my shop apron. Carl.

BORKBOB · 02-24-2009, 06:59 PM

Early into it I was equally frustrated. Somebody put me onto this burnisher and the instructions: http://www.stewmac.com/shop/Tools/Sc...6.html#details . The DVD was not offered then so when I got it, I read the instructions, did what they said to do, and pulled some righteous shavings first time.

Scraper was a BAHCO too..still my favorite.

KevinK · 02-24-2009, 08:39 PM

Hi

I am a little confused is this a card scraper or a cabinet scraper, a cabinet scraper looks a lot like a spokeshave and does not necessarily have a burr, it does have a bevelled edge and is bent by a screw in the handle part.

Also you do not have to buy a burnishing tool right away, you can use a screwdrive as a burnisher. I would recomment (if it is a card scraper) you file the edge flat, put it in a vise and then run the burnisher at a slight angle (down) over the edge you just filed several times and that should give you the hook you are looking for.

Good Luck

Kevin

cathardo · 02-25-2009, 09:23 AM

Sorry for the confusion. It’s a CARD scraper, not a cabinet scraper, and Bahco not Banco (brand is a bit worn down due to attempts to hone the face).

I assumed I would not need a burnisher to start. I’ll have no qualms purchasing one once I learn to use this thing, but one thing at a time. I forgot to bring the scraper home last night, so I haven’t tried anything, but as Kevin and Mike suggest, and reviewing several instructions, I believe I was trying to raise the burr incorrectly. I’ll let you know results

jeffreythree · 02-25-2009, 04:53 PM

I had the same problem when I first started using scrapers. Bought a Veritas burnishing tool that lets you set the angle on the side. No problems since then. The strange thing is the instructions say not to use to much oil. They said to rub your finger behind your ear and the oil left on your finger tip was just the right amount to rub on the edge to burnish.

cathardo · 02-26-2009, 09:36 AM

It’s ALIVE, It’s ALIVE, well maybe not alive but it does shave curls. (itsy bitsy curls). I’ve been told working with a card scraper is a lot like learning to whistle. It takes effort to learn how to make the first sound, but from there you’ll be blowing tunes in no time. Now that I have learned to make the first burr, it’s time to practice to learn the melody. Thanks all.

Next, learning to carve a fan, but that will be a while.