Jointer vs. Conical disk?

[JPG]

I don't think it is caused only by table flex. It is important to get the table exactly 90 degrees from the sandpaper on the disk. This is an almost impossible task, especially if there are differences in the thickness of the grit and if the paper is perfectly smoothly applied to the disk.

Another strong possibility is variations in the speed of movement of the workpiece. As we all know - if a slower pass is used, more wood will be sanded. If you want to test this, get a sample workpiece that is just barely touching the sanding disk - pass it along and let it stall for a few seconds at one spot.

Any irregular speeds of the workpiece will cause an irregular edge. It is also what I call wavy when the 90 degree angle between the table and the disk is off a small amount. Parts of the edge where it joins a face will show the irregularity.

I forgot about this, but the steel disks do flex.

[fitzhugh]

Thanks for the link. I did not think about using hot glue once the shims were in place. I think I will try that next time since I believe it will take less time. Infeed/outfeed support with SS will be tedious.
Forrest

Be sure to note that in the video he includes a screwed wood lip that keeps the workpiece from being launched by the planer blades - the hot glue is enough to keep the shims in place and the workpiece on the shims, but only with the lip countering the forces from the planer knives.