Fading is used to disengage the rosette during certain parts of the object's revolution.
As shown in the second picture to the left, the area in blue is where the rosette is outlining the pattern, and the area in red is where the fading wedge has disengaged the rosette. The amount of fading determines the amount of part which is red, vs. which is blue.
On the MDF rose engine lathe, this is implemented using a wedge. The fading wedge is shown in the picture on the right. It is the part with the scale markings on yellow tape (inside the red box).
To use it, the black, lower thumb screw is loosened and the wedge slid down between the headstock and the body. The amount it is lowered determines the amount of fading. Once in place, the thumb screw is then tightened to keep the setting in place.
There are other approaches, including use of a retractor, where the fading is increased or decreased by a linkage to the spindle drive. This could be used in conjunction with movement of the cutting frame (i.e., by use of a leadscrew) to create some really amazing art.
Examples of this device in use
- This YouTube video, MDF Rose Engine Lathe : #9 - Fading, is a quick overview of of fading on the MDF Rose Engine lathe.
How it works
The picture to the right shows what part of the machine determines the cutting of the shape of the object. It is an end view of the object, showing the parts of the rotational cycle where there is an exchange on which part drives the shape.
- When the Fading Wedge is engaged more, the
red slices of the "pie" are more prominent in the cut pattern.
- Conversely, when the Fading Wedge is engaged less, the
blue slices of the "pie" become more prominent in the cut pattern (showing the effects of the rosette more).
Disclaimer: eMail comments to me at OTBookOfKnowledge @ Gmail.com. The process of woodturning involves the use of tools, machinery and materials which could cause injury or be a health hazard unless proper precautions are taken, including the wearing of appropriate protective equipment.