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Steve Lindsay
12-17-2010, 11:45 AM
I sometimes receive questions about learning to make first cuts with the AirGraver. Below is a tutorial from the school site that should help. I tried copy-and-pasting it in this post but if the formatting doesn't display well here you can visit the page on the school site (http://www.engravingschool.com/private/tut1.htm) to see it.



Tutorial 1
I want to stress treating the practice plate like a piece of scrap paper. Feel free to doodle on it just as you would a sheet of scratch paper, as if you were learning how to use a pencil or paint brush. Later, when you feel comfortable and more confident with the graver, you can make a more formal plate for presentation.
Start with some straight line cuts that taper in and out evenly. This is going to help you learn to coordinate the foot control with hand movement. Set the AirGraver length of stroke so that half to 3/4 of the first exhaust hole is showing, and set the drive regulator (the regulator on the right) to 25 to 30 psi.
Note: the metal used in these videos is from OnlineMetals.com. It is 2"x 3"x 3/8" thick (1018 cold rolled steel). The plate is as received from OnlineMetals, with no extra preparation of the finish. If you want a better finish for a presentation plate, you can take the time to sand (by hand or with a belt sander) through the sandpaper grits, but for scrap practice plates this isn't necessary. More info on practice plates (http://www.engravingschool.com/private/practiceplates.htm)

http://www.engravingschool.com/private/images/straight1.jpg

The angle of the graver to the metal is going to start high, scoop in and then slowly out. Make the cuts approx 3/8" to 1/2" long.
http://www.engravingschool.com/private/images/straight2.jpg

It is similar to the action of scooping ice-cream out with a spoon, but with less arching movement.
http://www.engravingschool.com/private/images/straight3.jpg
The scooping into the metal is the easy part, but now as you come up out, you need to back off the throttle just as slowly as you increased it.
http://www.engravingschool.com/private/images/straight5.jpg
You also need to be careful coming up out of the metal to decrease how much pressure you are using to hold the graver in the cut, so that when you get to the end you don't slip out across the plate.
Straight line video: Tutorial1a.wmv (http://www.engravingschool.com/private/images/tutorial1a.wmv)



Arc Lines
After you begin to master the straight cut, try the same thing but rotate the vise to make some arc scoop cuts. The cuts in the video are a little over 3/8" long. You might try some longer and shorter. Arc line video: Tutorial1b.wmv (http://www.engravingschool.com/private/images/tutorial1b.wmv)



http://www.engravingschool.com/private/images/arc1.jpghttp://www.engravingschool.com/private/images/arc2.jpg
http://www.engravingschool.com/private/images/arc3.jpghttp://www.engravingschool.com/private/images/arc4.jpg



Flared arc cut


Now try flaring the cut by rolling the graver to the outside. Start the cut upright, and slowly roll it to the outside of the cut.Flared arc video (http://www.engravingschool.com/private/images/line3.wmv)





http://www.engravingschool.com/private/images/line031.jpghttp://www.engravingschool.com/private/images/line032.jpg
http://www.engravingschool.com/private/images/line033.jpghttp://www.engravingschool.com/private/images/line034.jpg


Gentle 'S' Arc
Same idea, but turn the vise first one way and then the other. Video (http://www.engravingschool.com/private/images/line4.wmv)
http://www.engravingschool.com/private/images/line41.jpghttp://www.engravingschool.com/private/images/line42.jpg
http://www.engravingschool.com/private/images/line43.jpghttp://www.engravingschool.com/private/images/line44.jpg


Motif A
Now we start to put the cuts together to form some motifs. First do an arc cut and flare it some if you like, and add a small radius arc top to it. The small cut is the same arc cut we have been doing, but not as deep. Video (http://www.engravingschool.com/private/images/line5.wmv)
http://www.engravingschool.com/private/images/line51.jpghttp://www.engravingschool.com/private/images/line52.jpg
http://www.engravingschool.com/private/images/line53.jpghttp://www.engravingschool.com/private/images/line54.jpg

Motif B
The first two cuts in this are the same as above but now add an additional gentle flared 'S' and another arc to form a leaf. Video (http://www.engravingschool.com/private/images/line6.wmv)

http://www.engravingschool.com/private/images/line61.jpghttp://www.engravingschool.com/private/images/line62.jpg
http://www.engravingschool.com/private/images/line63.jpghttp://www.engravingschool.com/private/images/line64.jpg

Motif C




Same idea as above, but with the last two cuts differentVideo (http://www.engravingschool.com/private/images/line7.wmv)




http://www.engravingschool.com/private/images/line71.jpghttp://www.engravingschool.com/private/images/line72.jpg
http://www.engravingschool.com/private/images/line73.jpghttp://www.engravingschool.com/private/images/line74.jpg

Motif D




Another variation Video (http://www.engravingschool.com/private/images/line8.wmv)

http://www.engravingschool.com/private/images/line81.jpghttp://www.engravingschool.com/private/images/line82.jpg
http://www.engravingschool.com/private/images/line83.jpghttp://www.engravingschool.com/private/images/line84.jpg

Motif E




Here is the head of a scroll that is sometimes used in scroll Video (http://www.engravingschool.com/private/images/line9.wmv)

http://www.engravingschool.com/private/images/line91.jpghttp://www.engravingschool.com/private/images/line92.jpg
http://www.engravingschool.com/private/images/line93.jpghttp://www.engravingschool.com/private/images/line94.jpg
Motif F



Another basic motif head that isVideo (http://www.engravingschool.com/private/images/line10.wmv)

http://www.engravingschool.com/private/images/lind101.jpghttp://www.engravingschool.com/private/images/lind102.jpg
http://www.engravingschool.com/private/images/lind103.jpghttp://www.engravingschool.com/private/images/lind104.jpg

Motif G




Now try going on your own, using this variety of cuts to create interesting leaves and motifs.Video (http://www.engravingschool.com/private/images/line11.wmv)




http://www.engravingschool.com/private/images/line111.jpghttp://www.engravingschool.com/private/images/line112.jpg
http://www.engravingschool.com/private/images/line113.jpghttp://www.engravingschool.com/private/images/line114.jpg

SVD
12-18-2010, 06:19 AM
Thanks Steve!

Not only good AirGraver practice but good basic practice overall. :thumb[1]:

Plus I like how it shows what I feel is the real magic of Engraving:

You take this little tool and it cuts lines in metal. You make a simple cut, then a couple more and... there's a leaf!

People think engraving is tedious but to me it's just like Assembly language programming. Everything you do is, in and of itself, very simple and easy - heck, the most complicated thing in everything you show above is a flared S cut and how hard is that? But if you keep doing those little, simple things they add up. And if you add them together the right way you wind up with something wonderful!

MCMLXX
12-18-2010, 08:46 PM
little things make the whole? you got it.
.... but does it go side ways?
d

Hybridfiat
12-19-2010, 01:48 AM
Thank you for these hints Steve. A year ago when I picked up an engraver for the first time this is the very tutorial I followed. Starting with the very simplest line and filling a prac plate with them then onto the gentle curves and another 100 or so swoops. It helped tremendously. Little steps that lead to more complex forms. I think from viewing many beginners attempts, that they give in to the temptation to do a complex pattern or design and become discouraged when the result is messy.
:hurray[1]:

KMazur
12-19-2010, 03:30 AM
This is very instructive. Thanks a lot Steve Lindsay.