Cutting a "delta wing" can be tricky and sometimes impossible...

If your wing has a very high "backSweep" then it may not fit into the bed of your machine.

Further more if the tip chord is way shorter than the root one, the tip will be burnt...

"Only" solution :

• turn your stock, put the Leading Edge of the wing parallel to the hotwire... and apply these tricks !
• follow the root and tip profiles at constant same speed on both sides until you reach the trailing edge of the tip
• then, on tip side, follow the trailing edge of the wing, while, on root side, you follow the rest of the root profile

This idea is not mine and has been developped by Christophe Lauverjat and "Papy KiloWatt".

So, original ideas and credit go to Christophe : https://www.cncpartage.fr/archive-christophe-lauverjat/christophe.lauverjat.pagesperso-orange.fr/decoupecnc/telechgt.html

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Advantages :

• you can cut big delta wing on a "normal" bed
• the tip side is not burnt (as cut at the exact same root speed)

Drawbacks :

• root end of profile will be somehow "flattened" after the end of the tip side
• it means that, although root and tip profiles are fully respected, intermediate profiles are a little flattened.
• it can be "worse" for wings with big washout angle (horten style wings)

usage : 

• launch WiHoWI and import profiles as usual
• tune real wing length
• tune back sweep
• tune washout (but drawbacks are increased with high washout angles...)

Then select the menu tools "Delta wing"

5 files will be generated and saved : 

• 2x .dxf for the projected profiles (with new projected chords)
• 2x .dat for the projected profiles (normalized and without the chords)
• 1x readme file with all geometry of the rotated wing

  Profiles for delta wings (WiHoWi menu tools)
  ============================================
  panel length                 : 575.66 mm
  wing length                  : 500.00 mm
  back sweep angle             : 21.80 °
  back sweep on wing           : 200 mm
  dist to root trailing edge   : 75.66 mm
  root chord                   : 300.0 mm
  tip chord                    : 100.0 mm
  root/tip chords projected    : 279.57 mm
  

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Import the profiles into WiHoWi, 

• tune the news chords (bigger because of the backSweep angle)
• tune the panel length (into the wingLength field ...I forgot to do it in the picture !...)
• cut your stock at the dimensions of the finished wing
• turn your stock with the backSweep angle
• and cut these strange profiles !
• trim the "triangles" on root and tip sides to recover the finished delta shape

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You will notice that the hotwire acts as a pair of scissors when cutting the wing trailing edge. It's normal ! (Y direction is changing at the root trailing edge into the foam -not the wing-).

Remember that this tool has limited performances for wing with high washout (horten style)... Sanding an edge, after the tip TE and before the root TE, might be needed !

Try it, it may help in desperate situations !