ROS Control on narrow workpieces

[Cody Eaton]

I make small boxes and I am having some control issues with my ROS sander when sanding the sides of the boxes which are about 2.5 inches wide. The problem gets worse when it get to the ends/corners of the side. It’s almost as if the sander is grabbing the sides or the corners and wants to pull it in various directions. I am using a Bosch ROS20VS sander which has been a great sander otherwise. I have tried various techniques, lighter/more pressure, increase/decrease speed of the sander, make sure I am flat on the workpiece, but I still get the jerkiness. Could this just be the “random” part of this sander on narrow boards that is causing this? I am thinking maybe a 1/4 sheet sander may be a better option in this situation but want to make sure I rule out user error first and get this groups thoughts. I am typically sanding the sides with 150 grit if it matters.

[Frank Pratt]

I think Festool makes an attachment for their sanders for just this purpose. If you have a look at it, you may get some ideas for building one to fit your sander.

[Jim Becker]

I was going to mention what Frank did.

One other thing...do the majority of your sanding before you cut the material down to short lengths or to final width. That makes it a lot easier and often you can just do some hand sanding to finish things up after assembly.

[Brian Tymchak]

What Jim said. Also, I've ganged multiple small pieces together with some scrap of same thickness at the edges to balance the sander. I've used double sided tape to keep the pieces together.

[Zachary Hoyt]

I use a Bosch 3283 DVS sander (I have four of them of which two are still operational) to sand narrow surfaces and I think you should be all right if you take a little time to practice on scrap wood. I am not sure if it would be different with a top handle sander like yours. I am going to be applying finish to a batch of 7 banjos tomorrow and tonight I spent nearly 2 hours sanding them with 150 and then 220 grit discs. The sides of the pegheads are only 9/16" wide, and the dowel sticks are 3/4" square, but it's easy for me to control the sander now, because I've been doing this for 10 years so it's second nature. My arm got tired toward the end of the session. My experience is that when I'm sanding a larger surface I can push down a little or let the sander's weight hold it in place to some extent, but when I'm sanding things that are narrow and need to stay flat I have to hold the sander up more, so that it's just touching the wood and not really pressing on it, if that makes sense. I hold the neck in one hand and the sander in the other, so it's not the same as having the workpiece on a bench.

[glenn bradley]

I find this useful.
450053
It is a Klingspor badged Bosch 1295. I primarily use this for "large" surfaces on small parts that have a lot of end or partial end grain areas. It only gets used about every other year or so. It comes apart and store over the rafters.

Generally a few small parts do better with hand sanding. I have multiple sanding blocks with progressive grits. If something has bandsaw marks, a couple of swipes with 150 followed by a couple of swipes of 220 should get you there. If you find yourself doing excessive sanding to get the desired result, look to these problem areas:

- Using Big Box sandpaper that wears out quickly.
- Using paper after its useful life (see above).

It is important to remember that sandpaper is a 'wear part'. Like the brakes on your car, it has a finite useful life. Use beyond this finite point causes extra work, irregular results, and frustration. One of my sayings is that 'Cheap Sandpaper is a False Economy'. Using low quality abrasives or using high quality abrasives beyond their useful life is a waste of time and money.

[Stephen C Cunningham]

Glenn. I was thinking, "bring the work to the tool instead of the tool to the work", this looks perfect!
The only thing is, if i built every cool jig and tool mod i saw on the internet, I'd need a new garage to keep them in.

[Phil Mueller]

For pieces that small, lose the power and hand sand. We’re talking minutes of work. And frankly, you’re going to want to hand sand anyway to remove any swirl marks.