Sanding Hickory

[AustinMike]

I am using ETS EC 150/3 EQ and RTS 400 EQ trying to eliminate swirl marks when complete. I started with 120 grit and went thru 150 and 180 before applying a dark stain to hickory table tops. After refinishing 3 times repeating all grits each time, I am still getting orbital marks. I am using about 25 to 50% vacuum on CT 26. Is hickory a pain or am I totally learning how to sand again? The tools are new to me.

 

[Michael Kellough]

180 on a orbital sander is not fine enough before a stain. You will see swirls.
 
Maybe you do need to re-consider how you sand if you've stained after hand sanding in the past.
I'm sure you sanded with the grain then.

You can't sand with the grain using an orbital machine so you have to use a finer grit.
I'd go to 320 before staining unless you really want the wood to gain a lot of color. Then you'd be better off hand sanding to get plenty of stain retaining scratches that are parallel to the grain so the result doesn't look bad.

 

[KRKWW]

I've played around with the suction control on my CT 26 and found that I can go all the way down to the lowest setting with my ETS 125 and around 10% with my Rotex 150. This decrease in suction does make a difference in the "gripping" pressure.

 

[bdiemer]

I don't like to make extra work for anyone, but my go through the grits is usually 80, 100, 120, 150, 180, 220, 320. I sometimes skip the 80.

 

[Kev]

I don't like to make extra work for anyone, but my go through the grits is usually 80, 100, 120, 150, 180, 220, 320. I sometimes skip the 80.

Agree .. you just need to go finer.

Which type of abrasives are you using?

 

[ear3]

Can you tell if the marks are from the RTS (that would be my guess) or the ETS?  Just a question, is there a reason why are you using the RTS on a table top?  Is there some edging in the way that you have to get up against?  I've noticed contrasting scratch patterns when mixing these two sanders together when doing casework, and so as others have already suggested, go finer and specifically with the RTS, make sure you're going with the grain.  If you have to mix the RTS and ETS on this project I would try to make sure that the ETS is the last sander I used, so that it's overlapping and blending as much of the RTS sections as possible.  The ETS can be sanded in any direction.  It sometimes helps to do a final handsand with the grain direction as well.

 

[junk731]

Hickory can be a problem wood just as any wood with a high Jenka rating can be. If you have been able to sand swirl free in the past with other woods its something in your current technique. While sanding to a higher grit sounds good it seldom solves the problem. The swirls occur from improper technique which can be composed of several parts. Without seeing how you operate a sander no one can say, yah just sand to a higher grit. The typical stain manufacture recommend is sand to max. 180/220 for good absorption.

So things that can cause swirls:
too high a suction or no suction
not cleaning the wood surface in between grits
appling down pressure or holding the sander so it applies uneven
sandpaper selection and skipping grits
using worn out paper
trying to sand with the sander set at to low a speed, typically finish sand at highest speed
the actual speed your moving the sander and the motion your using
mechanical issues like a loose or bad pad

Like I said above without seeing the way you actually operate a sander all that can be given is hints where to look for the cause. There are lots of us sanding everyday without swirl marks even using the lower grits.

John

 

[Michael Kellough]

Can you tell if the marks are from the RTS (that would be my guess) or the ETS?  Just a question, is there a reason why are you using the RTS on a table top?  Is there some edging in the way that you have to get up against?  I've noticed contrasting scratch patterns when mixing these two sanders together when doing casework, and so as others have already suggested, go finer and specifically with the RTS, make sure you're going with the grain.  If you have to mix the RTS and ETS on this project I would try to make sure that the ETS is the last sander I used, so that it's overlapping and blending as much of the RTS sections as possible.  The ETS can be sanded in any direction.  It sometimes helps to do a final handsand with the grain direction as well.

Edward is right, the RTS leaves more visible scratches so it should not be used last.

That type of simple orbital sander is inferior to the random orbital sanders in terms of invisibility of scratches. In a perfect world you could get a random orbit sander that could go into corners. Until then there is still a use for the RTS but don't use it if you don't need to.

 

[AustinMike]

Thank all of you for your suggestions. The ETS was causing the swirls at first. I bought the RTS to possibly remove the ETS swirls since it was more of a "straight line" sander. I think it caused more issues.

I have tried not to apply pressure and used highest speed on both with low suction and slow movement. When going to 220 grit the stain absorption was much lighter. With my old Makita and PC I always went to at least 220 and 320 before stain or finish. Never did much hickory with it either. Never had swirl issues at any grit either.

I will use my old Makita to finish this project and use higher grits for future woods!  Thanks again.

 

[AustinMike]

My old PC 333 got rid of the swirls with 120 and 150 grit. Neither grit produced swirls. Used the Makita finishing sander at 180 and everything was fine. I cut off the end of the dust collection thing on my PC and the extractor hose just fit. Best of both worlds. The poor old Makita didn't understand any of that!