Jury still out on the SandFlee, and a new sanding tip

I finally have the SandFlee operating properly, although it took a 1/16" shim under one of the hinges to get the table level by the drum. I've installed the fence, which was an easy job. I haven't yet used it as a jointer, which is one reason why I bought it, but a preliminary test on a ragged edge looked promising. I need to plan out an interesting glue-up to give it a "field test".

However, I have been disappointed using it to flatten rings. I assumed that passing it over the roller would automatically remove any irregularities. What I seem to be finding instead is that when a ring is cut at an angle, forces may be released that prevent the ring from lying completely flat. This doesn't always happen, but has happened frequently enough to be an issue to contend with. When this happens, just sanding the gluing surface evenly, whether with the SandFlee or sandpaper glued to a flat tile, does not change things. The spaces are generally small, 1/32" or less.

What does work is selective sanding with the sandpaper glued to a tile. I look carefully at where there are spaces. You can use a flashlight or bulb, or strip of paper, to confirm. I then sand the surrounding areas that are too high by exerting unequal pressure on those spots, or if it's a corner, by just sanding that corner slightly. Then I check, and repeat the process as often as needed. The payoff is that you will not get a visible glueline between the rings. Sometimes there is enough flex in the ring for it to flatten out with pressure from the bowl press during glue-up, so it often becomes a judgment call.

The situation to avoid is a space that will not close when you exert pressure. That will result in a product that you won't be proud of. Take a break when you've "had it", then come back later. You'll be happier that you did!