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Jan 26, 2010

More on the Palette Knife . . .

One day I was doing a woodworking chore around the house, and daydreaming about being outside painting instead, when I looked down at the chisel in my hand. I had been musing about palette knives and why weren’t they sharp when we purchased them for the art supply store? We use our knives as spatulas to mix our color, and for laying it on -- and sometimes we use our knives as a scraper to take paint off -- and I thought, "Hey, if my palette knife had a sharp edge it would do a better job of scraping!"
So I ran upstairs into the kitchen and grabbed my motorized knife grinder and honed the edges of the knife to a sharpness that would cut paper, and then ran into my studio to try scraping some dried impasto off a painting in progress. (Of course, my woodworking chore was at this point completely forgotten -- a thing which would irritate my wife later in the day.) The difference was amazing. My newly sharpened palette knife sliced right through any crusty paint like a knife going through butter, and the flat surface left behind was perfect for new paint. Sweet! Gone was the underlying texture that interrupted the gestural motion of my finishing strokes. Gone were the annoying flickering highlights that often destroyed the depths of my darks. And gone was the warp and weave of the canvas when I wanted it, since my knife could now level the paint film to exactly the depth of the cloth. 
But then, with one careless stroke, I cut deeply into the underlying ground itself . . .which made me to utter a few choice swear words. 
At first I thought that must be the reason why palette knives don’t come sharp. So idiots like me don't cut down into our painting support. Or through our canvases. Then I remembered the chisel I'd been using that morning’s for my woodworking chore. Chisels don't unexpectedly dig into a surface, and they have an edge too. And a chisel is honed on the top side of the cutting edge, not the bottom. The bottom side is flat and that is what prevents the edge from unexpectedly taking a dive into the wood as you use it. So I went back to the art store and bought another palette knife. But this time I only honed the top side of the blade and left the bottom side as is.
And to my surprise, instant success! I could knife-off large passages of crusty paint with ease without fear of digging into the ground underneath. Pressed flat and firmly, the bottom of the blade would slide along the surface smoothly much like a wood plane. Now my palette knife had all the advantages of being sharp, with little of the risk.
So if you choose to modify your palette knife, and I recommend you do, there are a few minor things to know first:
  1. Palette knives with drop handles are best because you can lay the blade flat against the canvas or panel and still keep your fingers above the painting. (see photo to the right) Flat palette knives, which are more like spatulas, don't permit you to lay the blade along the surface without dragging your fingertips through the paint.
  1. Once you sharpen the palette knife it becomes a true knife. This is easy to forget as you work. You can cut yourself badly and I have done so. So be careful. Be aware that when you wipe the knife with a rag its edge can cut through the rag and into your hand. (Which is exactly what I did.)
  1. The easiest way to sharpen a palette knife is with the aid of a motorized grinder, such as a Magic Chef Knife sharpener, or something similar. I only need to draw the knife through my sharpener once or twice on the right side of the slot to get a fresh edge, and I don't have to do that often since the edge seems to hold a long time. For anyone who don't own or have access to a knife grinder, let a professional do it for you. Trust me, that edge will last quite a while.
  1. When scraping the crusty paint, lay the bottom of blade flat against the surface and not at an angle. Angles encourage digging and lifting and most of the time you won’t want that. As you slice, a slight sawing motion may help with the cut. But don't over do it. You  are not trying to dismember an elk. Some care is helpful
  1. I recommend making several light passes over trying to scrape everything off at once. This is true for woodworking as well. More of a shave than a slice.
  1. Scraping down a drier area of a painting still in progress will drop flecks  into any wet areas below. You can avoid this by flipping the painting around, or by tipping the top of the canvas towards you so the scrapings drop straight away from the surface.
  1. And finally, remember those flecks are still paint. Don't leave them lying about the studio. If there is lead white, or cadmium, or other potentially harmful pigments in those scrapings, then clean it up. I use damp paper towels to wipe the bits and pieces up. The dampness prevent any of the tiny flecks from being thrown up to where they might be inhaled.

9 reader comments:

Thomas Jefferson Kitts said...

Funny I had thought of that but decided there had to be a good reason why they are not sharp! I use a chisel to scrape mine down..

(reposted for "Anonymous)

Thomas Jefferson Kitts said...

You use a chisel to scrape down your paint? Might have to give that a try.

(reposted from other blog)

Thomas Jefferson Kitts said...

Just found your site, your work is very nice. Last night I used a cabinet scraper to recover one of my early experiments (I've been a woodworker for 30 years and a painter for 1 year). This is a 2 by 6 inch square of thin steel that you roll the edge to create a burr. You then hold it with two hands and curve it a bit to control what part of the scraper is in contact with the surface. Then you pull it toward you to remove the high spots. It won't remove large chucks of paint as easily as your sharpened knife, but can give you fine control in smoothing a surface in the final stages. You can find articles on how to sharpen and use one one many of the woodworker sites. Please don't confuse this with the "cabinet scrapers" with a handle, they will not work and will certainly damage the ground.

(reposted for Larry)

Thomas Jefferson Kitts said...


Thanks for your helpful comment. I think I'll track down a cabinet scraper and give it a try. I'm familiar with the tool but don't have one. And you are right, with a large (three inch or so) palette knife that has a thin blade, one can hold both the handle and tip and bend it slightly to gain more control where the edge shaves the paint film. In fact, that is what I do myself. Not so much as to make the bend permanenet, but enough to cause a curvature.

Didn't mention this because I didn't want to be responsible for anyone accidentally cutting their finger holding the tip.

The cabinet scraper you recommend is used as a final smoothing tool, isn't it? To smooth the wood without raising the grain? If so, it would be ideal for this purpose!

Thanks again,


Larry Carter said...


Yes the scraper is a smoothing tool. It is often used to remove glue that squeezes out of a joint and to smooth a wood surface without sanding. Really useful on end-grain.
I have a few laying around, I'll drop one in the mail after I get back from my weekend with my bride.


Thomas Jefferson Kitts said...

That sounds wonderful. I'll let you know when I receive it.

I just went into the studio to scrape down a painting when your comment came in. I was prepping the image for another layer of paint. A little plein air painting of a white church (shown in a later post), hence a lot of lead white went down and built up too quickly. I want to work it a bit in the studio to see where it goes. And maybe drag it out into the the real world again f the weather improves.

Have a great weekend.


Thomas Jefferson Kitts said...

And Larry, I just went to your blog.

http://lecarter.blogspot.com for anyone else who is interested.

I agree with you. It is difficult for a person to learn how to paint by drilling down into individual artist web sites. It is also difficult to teach anyone via the web as well. Mostly because it can be so difficult to differentiate between opinion and practical information, not to mention writing styles and abilities. Or rants. (And not to completely overlook the woo-woo factor which occasionally slips in . . . )

So hey, if you or anyone else has a specific question you think I can answer please feel free to ask. I promise I'll let you know when I believe I am offering something subjective, rather than objective. And I'll encourage experimentation and confirmation over mere opinion. And I'll certainly let you know when I don't know something, because sometimes that is the best answer of all.


Thomas Jefferson Kitts said...

Larry, I just received the scraper you made and mailed to me and will use it the next time it is seems appropriate.

I peeled back the tape and could feel the curled edge, so I know which direction to pull. Thank you so much for sending it.

Will post back what I think of it.


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