|Home » Forums » Cabinetmaking » Message||Login|
You are not logged in. Consider these WOODWEB Member advantages:
Swirl Marks in Unfinished Wood3/13/17
I am looking for suggestions on what to do on eliminating swirl marks in clear alder/maple (tight grain woods).
I am building a clear alder kitchen, and have all the face frames, fronts, and doors ready to sand and finish.
What I am having an issue with is all the swirl marks in the wood. I am using Rubin paper, 120 grit on a Festool ETS 150/3.
I went back to the Porter Cable Model 505 1/2 sheet sander with 3M 120 grit, and same results. Although prior to the dark stain they feel perfect.
The stain is Sherwin Williams BAC wiping stain. Recently we switched our stain samples out and no longer offer anything from Minwax. This new stain system is showing this problem where I never saw it with the Minwax.
I also used our old Dewalt and Bosch 5" ROS's with Lowes brand 120 grit, my Festool 90 with granat 120, and also the ETS 150/3 with Abranet 80/100/120, all having the same results; a swirl finish.
Am I being too critical working under LED lighting on the bench? I am wondering how to achieve a swirl free finish before proceeding, any help is greatly appreciated! There has got to be a solution to this. BTW, my pad on the ETS is in excellent condition.
With Alder I go 100g to 220g it takes more to sand Alder than Red Oak imo.
most of what i do is alder 120 is way to rough to stop at 180 is the minimum and even then with alder it is hard to get it swirl free
120 is the problem. At least go 150.
Ya, what he said.
Typical sanding grits:
150 bare wood ready for primer or clear coat.
180 bare wood ready for staining
240 grit sanding primer or sealer
320 grit or maroon scotchbrite between coats
as said 120 is the problem it is a mid step to a finish we go to 180 then 220 even 320 depending on desired finish
We just finished an alder kitchen that used a lacquer based dye. We had good luck sanding to 150 with ETS 125's but we had to dial the vacuum way back till it was just catching dust. That seemed to clear up any swirling, especially on finished skins. With oil stains we go to 180+ because of how the pigment lays in the scratch.
The biggest tricks to avoiding swirls is light pressure and not over sanding. You don't mention the state of your material before orbital sanding, but that has an effect also.
You need to be sure your back up pad continues to spin as you sanding for the sander to "randomize" the scratch.
Go out in your yard, hook up your plow to your tractor, and plow an 8" deep furrow but don't leave any marks in the grass. That is like what we try to do with orbital sanders.
Low pressure on the machine gives less depth of cut. Low angle led lights help you to see how much sanding is required. The quicker you stop the less swirl.
The last tip is to slow down your hand speed. The pad must spin to randomize the scratch, but it cannot do its job if it can't keep up with the speed of movement. The quicker you move the bigger the swirls.
If I'm doing a job that cannot have any scratch pattern I will often use a soft block with 180 or 220 to lightly scuff the surface to remove most of the remaining scratch. If you properly opened the surface in the previous steps it will have almost zero impact on final color.