Converting a TC paint scraper into a card scraper

[Arvind Srivaths]

Can one burnish a hook on a TC blade with a harder material (say a diamond coated rod) and use it like a card scraper?

I tried a steel scraper from two cherries (0.6 mm) and one from Arno ( French Spring Steel Super Hard 1 mm) and a hss plane blade. Flattened the sides and edge (back and bevel for plane blade) and burnished a hook with a carbide rod. Got shavings but the hook doesn't last on the steel scrapers. Hss is decent but I thought why not try TC. Can someone explain why it will/won't work - there's a post where someone claims that it worked. After all if the geometry is the same and material is harder, it should work.

Here's a link to the post (by robert raess):
https://sawmillcreek.org/showthread.php?162935-Card-Scraper-Buying-Advice-Needed/page2&p=1671073#post1671073

And here's a TC scraper:
https://www.diy.com/departments/harris-2-heavy-duty-scraper/36385_BQ.prd

Thanks,
Arvind

[Jim Koepke]

Years have past with me trying to use a card scraper. Finally after all these years there has been some improvement. Still not getting the legendary continuous curls of scraper lore.

Almost any hard substance can be made to scrape wood. Some folks even prefer freshly cut glass.

One of my recent dives into scraper type instruments was done by grinding a 90º bevel on a cheap chisel:

472932

This works like a float with one tooth. It can be also be used on metal to remove rust.

So a TC Scraper may be a likely candidate for scraping wood surfaces. To discover whether or not it will suit your needs might cost you a few Quid.

Let us know how it comes out.

jtk

[Kevin Jenness]

Can one burnish a hook on a TC blade with a harder material (say a diamond coated rod) and use it like a card scraper?

I tried a steel scraper from two cherries (0.6 mm) and one from Arno ( French Spring Steel Super Hard 1 mm) and a hss plane blade. Flattened the sides and edge (back and bevel for plane blade) and burnished a hook with a carbide rod. Got shavings but the hook doesn't last on the steel scrapers. Hss is decent but I thought why not try TC. Can someone explain why it will/won't work - there's a post where someone claims that it worked. After all if the geometry is the same and material is harder, it should work.

Here's a link to the post (by robert raess):
https://sawmillcreek.org/showthread.php?162935-Card-Scraper-Buying-Advice-Needed/page2&p=1671073#post1671073

And here's a TC scraper:
https://www.diy.com/departments/harris-2-heavy-duty-scraper/36385_BQ.prd

Thanks,
Arvind

Never tried it. You should and report back. Maybe you will establish a new trend. You will need a diamond hone to sharpen. Turning a burr seems unlikely as carbide is so brittle but you will find out.

Sharpening a steel scraper is a little tricky, not hard but takes some practice. You can get a useable burr for rough work just by filing or grinding a square edge. After smoothing the faces and edges with a stone a fine burr can be turned that will last what I consider a reasonable amount of time, can be flattened and returned a number of times before refiling and can be refined with fine sandpaper. The trick is to hold the burnisher at a low angle (5-10*) and use light pressure. A fine burr will last longer than a coarse one.

[Bruce Mack]

Not quite what you asked, but this Red Devil steel bladed paint scraper allows me heavier shavings than my weak grip permits with a card scraper. The blade hooks readily with a burnisher. If you don’t like it, it has been an inexpensive foray and it can be used for its intended purpose.

[Richard Coers]

No you can't turn a burr on TG. To make a traditional burr on a scraper you have to move metal. You can make it very sharp and it will scrape, but not with a burr. Lots of old furniture refinishers used glass as scrapers because the edge with hard and sharp.

[Edward Weber]

I answered in the previous thread but her's my take on your question.

Tungsten carbide is an alloy of tungsten and carbon, made by heating tungsten powder (https://www.thomasnet.com/products/tungsten-powder-62464904-1.html) with carbon and hydrogen at 1,400 - 1,600°C (2,550 - 2,900°F). The resulting alloy is 2-3 times as rigid as steel and has a compressive strength surpassing all known melted, cast, and forged metals. It is highly resistant to deformation and keeps its stability at both extreme cold and hot temperatures.

Normal card (cabinet) scrapers are made of flat steel and a hook is drawn out by using a burnisher which work hardens the edge as it's formed. How long a burr lasts depends on the properties of the steel and how well it was formed.
This process can not be done on TC, due to it's physical properties. You may be able to sharpen a TC scraper with a diamond plate but you can not draw out a hook on it.

Two different types of scraping

[Tom M King]

The only thing I use a Tungsten Carbide scraper for is gouging out cracks in old plaster. You can do finish work on house parts with a Red Devil scraper, but I would use a card scraper on furniture. I get more done with a 1" scraper than a wider one, because you can easily put more pressure on it. Sharpening with a 6 or 8" Mill file puts it to work.

Here's the scraper I use. It has a 1" Red Devil blade, but the handle is much better. This is sold by flooring finishing suppliers, and is what most Pro floor finishers use for scraping corners of floors. https://www.floorsupplies.net/products/1-x-11-wooden-handle-floor-scraper-with-red-devil-blade?variant=32044992331908&currency=USD&utm_medium=product_sync&utm_source=google&utm_content=sag_organic&utm_campaign=sag_organic&utm_campaign=gs-2020-04-02&utm_source=google&utm_medium=smart_campaign&gclid=Cj0KCQiA0eOPBhCGARIsAFIwTs4WZyMP57HSNxddsSdm o67_g66DVAVMnpPMt2TeBleWRq9GmLre_BEaAm4kEALw_wcB

That scraper provided the finish before varnishing these 1850 doors. No sanding was done. A days work each with a heat gun, supplied air, and that scraper sharpened many times with a file to get 166 years of coats of paint off.

[Arvind Srivaths]

Plastic deformation may happen as theorized here?
https://scienceofsharp.com/2015/03/01/the-diamond-plate-progression/comment-page-1/#comment-9560

[Arvind Srivaths]

Thanks everyone for the suggestions - I will give it a shot and report.