Thread: Practice cuts
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Old 12-17-2010, 11:45 AM
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Steve Lindsay Steve Lindsay is offline
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Default Practice cuts

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 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


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.

It is similar to the action of scooping ice-cream out with a spoon, but with less arching movement.

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.

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



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








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








Gentle 'S' Arc
Same idea, but turn the vise first one way and then the other. Video



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


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



Motif C




Same idea as above, but with the last two cuts differentVideo






Motif D




Another variation Video



Motif E




Here is the head of a scroll that is sometimes used in scroll Video


Motif F



Another basic motif head that isVideo



Motif G




Now try going on your own, using this variety of cuts to create interesting leaves and motifs.Video





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