Contour Method: Making the Cut
Using Wire EDM

Principle:

Make Cut

Measure Surface

Calculate Stress

• Make a very straight cut
• Not remove any further material from already cut surfaces
• Not put in any stresses

So we use wire EDM (Electric Discharge Machining) Uses an electrically charged wire A spark jumps from the wire to the workpiece Material is locally vaporized The wire never contacts the part! Puts in virtually no stress if cut in "skim cut" mode drawing: Charmilles

Pictures of EDM cutting for contour measurements:

It is important to carefully fixture the part during cutting to keep the cut plane from moving as stresses relax. So here are some samples of clamping the part:

A newly designed fixture that does a very nice job of holding the part. The part shown here is a Ti-6Al-4V friction stir weld (FSW).

This is the clamping and cut for a large aluminum forging, see forging results page.	This is the clamping for the weld plate (results page). This plate has already been cut, you can see the cut running horizontally in the picture.
This is the clamping for a friction stir weld between 7050 and 2024 aluminum (see results page).	This is the clamping for a piece of British rail. The cut went from front to back in this picture. The shiny regions is where rust was cleaned away to improve the cutting. Results to appear soon.