: I continue to have concerns about proper sanding of my hulls prior
: to glassing. I have tried planning, belt sanders, ros and
: several grits of paper. I'm just not confident that I am getting
: the best quality sanding job placesdone. I am seeing some poorly
: sanded areas as well as blotchyness that may be from uneven
: sanding. I dont notice these until I add epoxy at which time it
: really stands out. I do wet the wood slightly to look for
: unsanded places.

: Right now I am sanding using a ros and 40 grit followed by 120
: grit. I am also using a fairing board with the same grit paper
: as above.

: Am I missing something or just not sanding enough?

With the ROS, don't press down hard, keep it flat where possible, keep it moving, don't overuse sand-paper.

40 is coarse, I use it mainly for carving closed cell foam.

I would start with 60, sand until the glue stains between and around strips are almost, but not quite gone, then move to 100 and continue until the glue lines are clean, then move to 140 then 180.

The first stage you can regard as fairing, the three further stages are really fairing the abrasion of the first stage. You don't need to overdo each stage, when it is done it is done, move on.

The idea is that each level of grit is used to even out the micro-gouges of the previous grit. If you go directly from coarse to fine, you run the risk of not getting to the bottoms of the deeper gouges and you will see swirls under the finish.

The main thing though, especially with soft woods, is not to press, just keep the sander moving and let the machine do its job at its own pace.

I don't bother with fairing boards. The ROS does it for me. On raw dry soft timber I also like to run it with light pressure at higher speed, as this Keeps the gouges closer together and more evenly distributed across the surface.

I also try to work over biggish areas and keep moving. Try not to become obsessed with a particular square foot of the project, the whole surface needs to be worked together with overlapping strokes of the sander to keep everything nice and level.

Well, you asked!

Et