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Phil Thien
05-06-2015, 10:48 AM
The question on the difficulty of sharpening a card scraper got me to thinking...

Last year I was at the travelling wood show. They had the French guy there demonstrating his plane which uses utility blades. I ALWAYS watch this, never have purchased one but I will confess I've gotten close.

But while I was watching this time, I saw him take a fresh blade, and roll-over the edge using the shaft of a screwdriver. He proceeded to use it as a scraper (he had it mounted in the Rabit plane he sells). I had never tried this, I couldn't believe how well it seemed to be working.

Fast forward to a month later and I was having difficulty removing signs of dried glue from the corner of a small project and so I tried it myself. I was able to hold/control the blade in my hand, set it in the corner, and scape the evidence of glue right out. It couldn't have worked better.

How many of you have used this trick?

Does it count as "Neanderthal?"

Oh, and when the rolled edge stops working (likely because the metal is abraded), you can roll the edge on the same blade a time or two more. So I will now often finish a project with one of these blades, instead of sandpaper. I may use sandpaper on edges, but I even use the razor/scraper on end-grain!

ian maybury
05-06-2015, 10:58 AM
Almost anything with a sharp corner or edge makes a decent scraper Phil. I haven't used a knife balde, but broken glass was common usage way back then in places here in Ireland - i used it all the time as a kid to shape curved parts like adjusting the fit of DIY dowels etc. I even made some fishing rods. It's especially easy on green wood.

A sharp pocket knife can used in a similar manner.

The glass requires care in handling and taping the other edges (although we never did) to avoid the risk of getting cut. The downside is that because the edge is never going to be straight it's not much use for scraping a flat surface...

Jim Koepke
05-06-2015, 11:19 AM
How many of you have used this trick?

I have used a single edge razor blade. Since it ruins the blade for anything else I haven't done it in a long time. Since then I have an old piece of broken saw blade that does the job.


Does it count as "Neanderthal?"

Sure, at least in my opinion. "Neanderthal woodworking is likely mostly about being able to make use of what ever is at hand.

jtk

Phil Thien
05-06-2015, 11:19 AM
Almost anything with a sharp corner or edge makes a decent scraper Phil.

Yeah I suppose I've always done that. But rolling the fine steel edge gives me performance similar to what I've had on card scrapers. Just smaller, faster, and easier.

For example, I've used the back of a chisel to clean a wee bit of dried glue from a corner, but it works nowhere as well as a razor with a turned-over edge.

Phil Thien
05-06-2015, 11:22 AM
I have used a single edge razor blade. Since it ruins the blade for anything else I haven't done it in a long time. Since then I have an old piece of broken saw blade that does the job.



Sure, at least in my opinion. "Neanderthal woodworking is likely mostly about being able to make use of what ever is at hand.

jtk

It didn't work well for me with a single-edge blade, I think they're too thin. The utility blade worked better. I'm using 50-packs of blades I get for $3. I get quite a bit of use from one, it will last an entire project like the small cabinet I just built. When I'm done, I toss it in a small can I have in the recycling bucket.

Malcolm Schweizer
05-06-2015, 11:36 AM
I use this all the time for scraping epoxy boat hulls. I also use it to spot scrape wood hulls before glassing, like where maybe I did a small repair and just want to smooth it after the rest of the hull has been scraped already. You don't even need to roll a burr- just use the razor right out of the box. Just be careful, because they snap, and when they do they sometimes bite!!!

Zach Dillinger
05-06-2015, 11:56 AM
Utility knife blades work great. So does broken glass (just cut it if you want a straight edge for a flat surface). Lots of way to get the job done. Just depends on who is selling what at the moment.

Dan Hulbert
05-06-2015, 1:27 PM
I've used just about everything mentioned so far, but my latest addtion to the scraper arsenal is a used thickness planer blade. I've found cutting an old blade in half and burnishing the edge abit works great. Leaves a nice square narrow end that works great getting glue our of corners.

Tom M King
05-06-2015, 1:42 PM
Many times.

Phil Thien
05-06-2015, 1:44 PM
I use this all the time for scraping epoxy boat hulls. I also use it to spot scrape wood hulls before glassing, like where maybe I did a small repair and just want to smooth it after the rest of the hull has been scraped already. You don't even need to roll a burr- just use the razor right out of the box. Just be careful, because they snap, and when they do they sometimes bite!!!

The burr makes it work 10x better, at least for me.

I'd used razors w/o burrs for years, but that burr is a game changer.

John Coloccia
05-06-2015, 1:47 PM
I do it all the time too, Phil. :)

Malcolm Schweizer
05-06-2015, 3:36 PM
The burr makes it work 10x better, at least for me.

I'd used razors w/o burrs for years, but that burr is a game changer.

Certainly will try it!

ian maybury
05-06-2015, 4:56 PM
The burr/turned edge presumably makes the scraper function as though it had a lower cutting angle and sharper bevel than just a square edge - much like adjusting the pitch/cutting angle with a plane. Almost another take on the micro bevel thing. Might be too that a less than top quality blade would work better - soft enough to make it possible to properly turn the edge......

Phil Thien
05-06-2015, 5:56 PM
The burr/turned edge presumably makes the scraper function as though it had a lower cutting angle and sharper bevel than just a square edge - much like adjusting the pitch/cutting angle with a plane. Almost another take on the micro bevel thing. Might be too that a less than top quality blade would work better - soft enough to make it possible to properly turn the edge......

The gentleman at the woodworking show ran the blade along the shaft of the screwdriver at about a 20-degree angle about ten times, five each from the center of the blade to the left edge, and another five from the center of the blade to the right edge. Then he increased the angle to about 45 degrees and just repeated but only 2-3 times in each direction.

When you're done, you can easily feel the burr with the finger.

Give it a try. It works great on end-grain.

Frederick Skelly
05-06-2015, 7:17 PM
I frequently scrape with singe edge razor blades and get good results. I'll try your suggestion and see how it works for me. Thanks Phil!

Jessica Pierce-LaRose
05-06-2015, 10:39 PM
I used to do it a lot on finishes, using a tip from Frank Ford - tape the outside edges, so it only cuts in the middle; then you can quickly get a high spot in the finish (from poor spraying or a repair) close enough to level to buff or sand as needed, without mucking up the rest of the finish more than needed.

John Coloccia
05-06-2015, 10:46 PM
I picked up that same technique from someone...may have been Ford or Erlewine. I've always wanted to try it with .001" plastic shim stock to see if it would hold up, but I never seem to remember to order any. That would REALLY get it close. :)