Thread: To cut Cleanly?
View Single Post
  #15  
Old 11-24-2006, 08:34 PM
Steve Ellsworth's Avatar
Steve Ellsworth Steve Ellsworth is offline
Platinum
 
Join Date: Apr 2006
Location: Highlands Ranch Colorado
Posts: 784
Default Re: To cut Cleanly?

Jim,
Sounds like you are getting closer to success.

A 55 degree face will hurt nothing. In fact for many it is a standard. 45 50 55 60. The greater the face angle the more strength you have with regards to working in different, tougher, metals.

45 or less presents a "weaker" tip. But far easier to see where its going under the scope than looking over a 55 or 60. Matching the graver strength to the metal is always the safest bet. That's why SL offers some variations on the theme for you to pick from and you can always dub the tip if you think you are going to break something.

If you are not forcing the tool it should make no difference. In actuality once you get it figured out as to the process of accurately sharpening the relief angles it doesn't make all that much of a difference what face you use. It's the relationship of the angles, Not the numbers.

Keep in mind jewelers look at things with 10x for a standard. They are not going to drag out a scope and go over your individual cuts with a fine tooth comb at 45x. Neither will the client, unless you are trying to present and compete in a world class engraving senerio. So if your design work is good and the cutswork well everyonewill be happy. It's very easy to get over critical and look at things too closely.

Another thing to bear in mind is all this reference to numbers is very sketchy stuff. If and when SL brings out his sharpener the issues willl be mute because it will be a no brainer. Today, if you can find two sharpening fixtures on the market that reference degrees accurately one to another or that are individually repeatable to any great extent you have an advantage over the rest of us. These fixtures have so much slop in them that there is no logic in using them past the point of rough shaping (1200 grit) when you are first starting out. When faceting it is extreamly tough to get the angles right, using a fixture. Invariably using the fixture and a wheel, the heels will be off center or cut too long. This can only be verified through the scope and at considerable power. It is amazing how little an angle has to be off to screw things up.

Discarding degrees and all that. If you hold the Airgraver at a comfortable angle graver tip down and there is enough room for yoour fingers to hold the tool and move over the metal you are about there. Translate that to your fixture setting. It may turn out to be 17.5 or it may be different. The bottom line is simply this. If the angle of attack is too shallow the graver will have a tendancy to skate out of the cut. If it's too steep, you dig your way to China and cut huge trenches with distortion. But that is not to say that greater angles are not useful. It depends on the surface you are trying to get to. Sometimes you can only do certain areas with a graver that comes in realatively steep. In my realm, carving coins, the majority of my gravers are set to come in at a pretty high angle simply to clear the rim of the coin if nothing else. Others are set at more traditional angles for flat art engraving.

The chosen graver angle is the sum total of the balencing act between hand, vise position and material. Eventually you may end up with a collection of gravers with a lot of differnt grinds.

Some of the folks who visit here have literally hundreds of gravers set to perform certain functions. Some get used constantly others sit on the bench till needed.

For the average person 90 110 120 and if you are brave a 130. Flats will vary by the job. I have a love for very large knife gravers in lieu of flats. It's all a matter ofplaying till you get it right.

Have fun and keep cutting.

BTW copper has a tendancy to distort. I do alot of it. There are different grades available. Get the harder stuff to play with. Don't expect copper to cut much like Gold. It doesn't. Gold is way more fun. If you pick up copper water pipe it makes for a nice material to learn on and you get to play on curves too.

Long curls are not a bad thing. The curl is your best indicator of the consistancy of your line depth and width. You need to pay attention to it.

SLE
__________________
CoinCutter
Reply With Quote