Thread: To cut Cleanly?
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Old 11-20-2006, 10:49 PM
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Steve Ellsworth Steve Ellsworth is offline
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Join Date: Apr 2006
Location: Highlands Ranch Colorado
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Smile Perhaps this will help -

Without seeing your problem or watching tou cut it's a bit hard to pinpoint exactly but here are a few thoughts on a couple of possibilites.

First of all lets take some of the mystery out of the graver cuts steel process and see if we can't simplify this so you can get on with engraving.

The trick to this is to stop thinking likean engraver and start imagining yourself sitting on the tip of the grave as it works it's way through the metal.
Now while this may sound strange to you it will help. For a long time I had problems sharpening tools. I Couldget real close but never could get the ultimate grind and ofcourse at that time Lindsay wasn't telling. One night i actually had this dream, there i was sitting on the graver, watching the tip hit the metal and as it cleaved it flowed off the sides like water against the bow of the boat. The next morning i shapened my first gravers correctly.

YOu say you are resharpening and checking under the scope alot. That tells me something is wrong. You simply don't have to sharpen that often if your gravers is properly prepared. Gravers don't cut, they cleave. It's a molecular level pushing and spreading. But not a cut. So the tip has to be sufficiently small to do this at a size considered acceptable for engraving. While it may seem logical that the tip should have a sharp point that doesn't hold up because it's not nice to try to turn a very tiny graver point in a radius, it will dig in and break. Or gouge things. By putting an extreamly small secondary face on the tip of the graver that problem is elimininated. It also has the benefit of allowing you to come out of the cut cleaner. Logic of this is that the shape of the tip dictates the shape of the removed metal and it's stress state when you flick it. The mini secondary presents a square edge cutting surface along its top which acts completely differntly upon the metal than a sharp point which can only rips its way up. This little upthrust will deform the end of the cut. Knowing that you have two choices, either change your graver or change your style and reverse cut. Chances are you will have to do a reverse cut either way to maintain line width but you will have far better luck with the "dubbed" tip.

If you are seeing this deformation along the entire lenght of the cut. Your sides of your graver are not sharpend to a height sufficient to cover the depth of your line and you are pushing the metal not cleaving it, and chances are you have the relief angels ground incorrectly. in short it sounds like the metal being removed doesnt have any where to go so its being forced against the side will of the cut and raising an edge.

WHen you are cutting the metal should come up in a nice curl or chips and move foreward or in some fashion spiral out of the way. Anything else means dull graver.

Pay attention to sharpening those surfaces which come into contact with the metal when doing the work. Polish at 90 degrees to your hone marks. Use tap lube or something similar.

Also check to see if what you are cutting deforms easily. Lots of possibilites.

Second senerio is not so much your hand control but your foot control. I suppose this applies to the Palm too but in a different sense.

One of the hardest things to learn about running an Airgraver with foot control is how to control the air fall off at the end of the cut. You can't be running full power when you hit the end of the line. You run the risk of distorting the end of the cut as the graver is coming up and banging away with all the force it needed to cut the line only now rising up there is less metal to resist the impact so as the tip of the graver comes up to the top surface of the metal while impacting things get mushed. Neither can you go to slow. It's a matter of practice and it may take you some time. If you have a foot pedal build a rest so you can mount it just like its a car gas pedal at an angle. Trying to work it as it comes out of the boxis not good. Now you can run it with your toe if you's like and have much better control. Your gaver hand and foot must run in complete harmony. Just like driving a car.But the pedal is both accelerator and brake. Learn to use as both
keeping in consideration the foot responds slower than the hand in 99.9 percent of the population.

If you have resharpend the tool you got from Steve that was sharpened you need to order another one to study. Dont ever screw with it. Just look at it under the scope and use it as a model to compare your other gravers against. Only after learning to replicate it do you mess with it. Then you can play with differnt angles heels and what not.

So the odds are that you simply need to sharpen correctly and learn what your Airgraver will do for you. There is the key. Let it do the work. Guide it left andright roll it back and forth. See what each graver does in a piece of metal at different impact rates and air power. It's not so much learning how to engrave as it is learning to draw with a new kind of pencil. If you don't know what it can do you wont know how to engrave with it. So screw up a lot of junk metal and see. Push it to it's limits and back it way down so slow and smooth you dont know its running. Stand the graver on it's nose and crank up the idle. DO that with every tool. Learn your pallet and then engrave (paint) with ease.

Keep the scope to see your sharpening attempts improve. Put it aside or use it on a very low power to work with. Get more involved with the line than the quality of the line. Then do other things. AS you do this you will get a feel for what the blade is going through. That will help you to understand sharpening as we have already discussed. Study your self as you work, step back in your head and watch your hand work with the Air graver. Watch it cut. Think about how much time you have to work the foot pedal to cut the air back to coincide with where your graver will slow to a stop. Then after you have played with this process for a while you can stop paying attention to all of the processes focus on creation. It 's like riding a bike for the first time. When it clicks it's with you forever. You simply have to drop the technical stuff for now and play with the tool like an artist, but not an extreamly picky artist at this stage of the game. Just slopping some stuff on the canvas to see how it all works out. Not trying for a masterpice. Just a sketch or two.

Trust me it's not that hard although many people tend to make it so.

SLE
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