Sanding Tips + Tricks
What we Discuss
- Avoid Swirl Marks
- What grit sequence you should sand in
- Important things to do between Grits
This is a common phrase to use for sanding marks seen in this photo
Avoiding Swirl Marks
Some causes of Swirl Marks:
- Damaged sanding disc pads
- Worn orbital sander bearings
- Poor sanding techniques
Practice these techniques:
- Sand in the same direction that the wood grain runs
- Do not angle your sander. This can cause pigtail sanding marks when pushing too heavily.
- Move your sander approximately 1" per second
We use Sia sanding discs that can be purchased Here
What grit sequence you should sand in
A general rule of thumb is increasing your grit sequence by 20g each stage. Once you get to the higher grits however, it is common to jump in larger sequences. If you are using an oil finish, the higher you sand will close off the wood grain more and not allow the oil to absorb into the wood pores as much.
If you have planed your piece flat, you can start sanding at 40g or 60g to remove any machine marks.
80g (good starting grit for hardwoods) > 100g > 120g > 150g > 180g etc
If you need to sand above 600g it is common to begin the process of 'wet sanding'. This is only necessary for certain finishes (such as lacquers or High gloss).
When sanding, you are essentially creating peaks and valleys. If you begin skipping grits in larger increments you are only able to remove the top of the sanding peak. Sanding creates small scratches in your wood grain that you are smoothing out. If you skip too many grits then you won't be able to remove those scratch marks and they will remain in your piece and become visible when finish is applied. Patience is the best thing to have while sanding.
We use a spray bottle to get an even water pop over the wood
Imporant things to do between Each Grit
Between Each grit you want to make sure you wipe off the dust so that fine wood particles aren't left behind. When you move up to a finer grit, those small wood particles could scratch the wood surface.
- Raising the grain to get a smoother sand and can reduce potential sanding swirls
- Helps with a more intense pigment penetration to achieve richer colours when putting a tinted finish on
- Helps keep a consistent colour on naturally blotchy wood species (such as maple)
- Make sure to let the piece fully dry before continuing to sand.
- Water pop between your last 3 grits on sanding levels