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Hand sanding efficiency2/4
Since I work on a lot of decorative furnitures and small pieces I do a lot of hand sanding (using block, sponge, hand).
I usually go as fast and press as hard on the block as possible.
recently, when sanding grain filler I begun easing off the pressure since the sandpaper had a tendency to pull the filler out. This also gave me a surface a little bit rougher (with more tooth).
This had led me to think that I may be burnishing my wood even though I don't sand past 150 grit.
I have often read to go hard when hand sanding but would I end up with better result If I use orbital sander like pressure with my block
Take a look at the Surf Prep 3 x 4 sander with foam pads. Will never go back to only hand sanding, much better consistincy and easier on the body.
Pressing as hard as you can is a good way to wear yourself out. Letting the paper do the work is what I've been told. But that doesn't work either. You have to go in between the two to make things work nicely.
Pressing hard, especially on corners wears the paper out faster but doesn't get the work done faster. As was said above the sponge sandpaper gives good pressures for most sanding, but not aggressive sanding.
Another thing I've noticed is that lower grits don't always remove wood faster. Especially if you have limited stroke such as small parts or in corners. More grit per inch sometimes is what makes the job go quicker. If you sand with 220 instead of 120 sometimes the more cutting edges will reduce your sanding time. You make have to go back with a lower grit to get the right surface for staining.
Heavy handed sanding leaves deeper scratches that may show in the finish. While lighter sanding won't and that will increase the speed of sanding in the end.
I also have the same problem as you, harder means faster. But it doesn't always work that way.
Abrasives are like any other cutting tool. Let the tool do the work.
Imagine you are using a variable speed random orbit sander. You’ve got four variables: grit, hardness of pad, speed of the sander, and how hard you push down on it.
The grit size is typically chosen by how deep a scratch you require. Heavy removal of material 60, epoxy prep 80, joinery smoothing 100, bare wood 150, primer 240, topcoats 320.
Hardness of pad is determined mostly by the shape of or by the material/substrate
Sand faster: sharp abrasive, speed of head or head pressure.
The efficient way is to run the sander or your hand at the highest speed possible. Then apply more pressure as required.
Think about lifting weights. Would rather lift 100 lbs once or 10lbs 10 times?
thanks everyone. I have tried to hand sand using the same pressure when than when I use an orbital sander on some scrap pieces.
the main reason behind this thread is that I have been getting inconsistent results regarding adhesion of my vinyl sealer/cv sealer/cv. I have tried thin coats, heavy coats/ exceding the dft/ staying way below the dft and even then could not get consistent results.
lately I made a few test pieces that were already sanded 120 grit and sanded them with a 150 grit. I wanted to go fast so I just hand scuffed with a 150 grit and to my surprise got fantastic results regarding adhesion of my cv over cv sealer over vinyl toner.
I have investigated and noticed than when sanding with a lot of pressure I something get areas of matte-satin sheen wich I assume must be burnished areas. This happen more with 150+ grits where I sometime end up rubbing the wood with a layer of sawdust clogged paper rather than sandpaper itself.
I am not a wood expert but read a few time that ash can cause adhesion problem if it end up burnished. I come from a softwood background and these woods sucked the finish like a charm even when burnished.
Clean it out by using your air gun, or by rubbing the sandpaper against a piece of carpet. You can rub the sandpaper against clean cardboard or against corrugated carboard, against the corrugation itself, but the cardboard dulls the sandpaper quicker than the compressed air or the carpet.
For surfaces that have a coating that's still o0ff-gassing, even though generally cured and ready for sanding, clean the sanded surfaces with a microfiber cloth to rag up the dust. The dust particles become sticky because as a fine particle it has more surface area exposed to off-gass whatever solvent is still part of the finish that had knitted itself together during the film-forming process.
Vinyl sealer is very, very thin. It usually only needs a scuff to create a tooth prior to coating over and not a subtractive form of abrasive removal. As long as their's no drips and as long as your VS is generally smooth, just a quick kiss with the sandpaper or Scotch-Brite is enough to give the VS surface some tooth.
Scuff pads clean sandpaper really well.