Apprehensive about posting here...among the purists

[Chris Barnett]

Have Lee Valley cabinet scrapers and it's time to get them sharp again. Since I do not have a burnisher, thought that I might just make one {so I can use it now and (2) it's cheaper - I'm frugal }. What might be the fault in having handles (like on a chisel) on both ends of hard steel rod. Seems that significant pressure is necessary to round over the edge, but since I have never done this, could be wrong and probably am since that type does not show in the tool sources. The steel bar that I have is soft steel so am considering using a old star drill....harder than .....well....it's hard...and available....just add handles. Alternatives? Suggestions...like, go back to power tools .
Thanks,
Chris

[Tim Atkins]

Sounds like a good use of a star bits. I have been looking for a good use for old ones. A large screwdriver will work for a bunisher.

[John Coloccia]

The shank of a spade bit works well.

If you put a handle on both sides, you will no longer be able to use it to "raise the burr", if you happen to use that step in your scraper sharpening.

BTW, you don't need a lot of pressure. You're only moving a tiny bit of steel. I would say that "moderate" pressure is about right. Maybe about the same as using a rolling pin.

[Michael Ray Smith]

I've read that valve stems (i.e., the sort of valve that's in an internal combustion engine) make good burnishers because they're very hard. Funny, though, I don't have a lot of valve stems lying around, so I can't speak from experience.

[Robert Rozaieski]

The biggest mistake new users of card scrapers typically make is using way too much pressure to turn the burr on the scraper. Keep in mind that the scraper is typically a finishing tool. While heavy card scrapers can be set up for "heavy" stock removal, the scraper's more common use is to put a finish ready surface on. So you want a fine edge, not a big aggressive burr. Two handed pressure when turning the burr would surely be way too much.

Draw the burr with the scraper laid flat on the bench and good pressure on the burnisher from one hand. You can do this part pretty hard, and in fact need to do it pretty hard in order to draw the steel out. Once the burr is drawn, turning the burr is done with very light pressure. I hold the scraper in my left hand with the edge to be turned facing up, and pass the burnisher about 10 times over the edge using light pressure; not much more pressure than the weight of the burnisher alone. A common analogy is to think about buttering sandwich bread. Too much pressure and you'll rip the bread apart. Use similar pressure when turning the burr on a scraper meant for finishing. For turning an aggressive burr for heavy scraping, you would use heavy one handed pressure when turning the burr. Two handed pressure is never needed for turning the burr.

[Zach Dillinger]

I've read that valve stems (i.e., the sort of valve that's in an internal combustion engine) make good burnishers because they're very hard. Funny, though, I don't have a lot of valve stems lying around, so I can't speak from experience.

Valve stems make excellent burnishers. I made my burnisher by cutting off the head of an old bent exhaust valve from my Datsun 280ZX, and mounting it in a quick-and-dirty turned handle. I've used it for 5 or so years now. Works great and no problems of any kind. I've heard that pushrods work well too, but I haven't tried one.

[george wilson]

correct,only moderate pressure is used. You do need a good,very hard burnisher so it doesn't gall against the scraper. The scraper itself has hardness,so,the burnisher must be quite hard. Back in the 60's,when I had few tools,I used a Proto brand screwdriver as a burnisher. Many cheaper screwdrivers may be too soft. They tend to be somewhat soft by nature,so the end doesn't snap off when twisting screws.

[Shaun Mahood]

Chris, the video that helped me actually get my first sharp scraper is here. Before seeing this I tried about half a dozen different times but it never clicked.

[Jim Matthews]

Rob has forgotten more about woodworking than I'm likely to learn - I take his advice seriously (built my bench based on his podcast, even).

Here's a link to William Ng setting up his card scraper. In the video, the card scraper makes an appearance after 3:09 in the video.
I had a visit with Mike Pekovich at a recent open house, and he showed a method for filing, squaring and honing a card scraper with a wooden block.
The block has a single kerf cut down the middle, turning the wooden block into a large clamp. The trick is in cutting the kerf perpendicular to the block face.

I also prepped the block so the sides are parallel to the kerf (and perpendicular to the block face) for quick touch up passes.
I use a DMT with coarse and fine faces, following the steps shown in the William Ng video.

As Mr. Rozaieski mentioned - it's a small surface to which your imparting force in a concentrated manner, a light touch works best.
My mistake as I first used card scrapers was in omitting the filing step - you've got to take off the work hardened steel for best results.

jim
wpt, ma

[Chris Friesen]

As others have said, too much pressure is bad. I liken it to the pressure of spreading peanut butter. More than the weight of the burnisher, but not much.

[James Baker SD]

Alternatives? Suggestions...like, go back to power tools .
Thanks,
Chris

Definitely do not go back to power tools. Stay here with us.
James

[Joe Fabbri]

I was just going to mention intake/exhaust valves. I didn't think anyone else thought of this.

I have a few huge valves I got from top fuel dragster engines, which I imagine must be top quality steel. I picked these up years ago when I used to go to the races. You find all sorts of engine parts laying around, as they tear down the engines all the time. I used one to make an espresso grind presser--I like my grinds pressed tight.... The other I used a few times just to burnish some homemade scrapers. It worked okay, I suppose, though I don't have much experience with scrapers.

[Jim Neeley]

Chris,

Be aware that many of us are "hybrid" hand and power users.. we just don't believe everything is best (or most pleasureably) done using power. Although yes, we have a few knuckle-draggers . <Ducking the flying bench dogs>

[Chris Barnett]

Thanks for much for all the info. Have watched part of the video....now to try his way. My scrapers worked well but are definately in need. Am sure I was heading in the wrong direction by brute force now that I read your comments and watch him. I go to the scrapers instead of sandpaper...don't like sanding but rather enjoy seeing the wispy curls from the scraper. I pull the scraper....he pushes...need to figure that out.
Again, thanks.

[Zahid Naqvi]

I have used thick scrapers without actually drawing a burr, just a nice clean and sharp 90 degree edge and it does a really god job. Doesn't work as well on thinner card scrapers.