sandpaper life

[Robert The Gray]

I unsure if this has been answered elsewhere, but how does one gauge when a sanding disk has lost its effectiveness? Do the lower grits wear faster? I am doing a refinishing project on a redwood deck. As I climb through the grits I wonder when I should be changing each disk out. I can tell when my knives or saws or drills are dull but the sanding disks have got me stumped. I imagine some wisdom from the group would help. How can one tell when to change out a consumable sanding disk?

r

[bcooke]

When I start thinking the disk isn't cutting as well as it should, I change it.

If I start having to lean into the material to make the paper cut, I change it.

If I start wondering about whether I should change it, I change it.

I don't know if the lower grits wear out faster. I do know that they feel rough long after they are worn out and stop being effective.

[Oscar]

If I start wondering about whether I should change it, I change it

Plus 1 minute.......

[Tim]

I imagine some wisdom from the group would help. How can one tell when to change out a consumable sanding disk?

The short answer is that it's almost always sooner than you think.

There's no golden rule; sandpaper is done when it's done. It greatly depends on the material being sanded. But like Britton mentioned, the paper will feel rough and often look good for a long time past its most efficient end of life, and this often leads people into using paper longer than they should.

Of course this isn't including the times when the paper becomes obviously clogged and clearly ineffective, such as what happens when sanding bottom paint or other soft materials that heat up and quickly clog the grit, which can render a new disc useless almost as soon as it's put to use.

The economics of sandpaper costs versus labor costs and the sweet spot between using new paper and holding onto old paper a little longer have been studied and surely written about in the past. The long and the short of it is that it's more expensive in the long run to over-use sandpaper, when one is factoring in labor costs; a new sanding discs cuts faster enough and better enough to more than offset its cost in terms of time saved.

Even your own "free" labor has a cost, and should be factored in to some extent at all times. So start to gauge how the paper acts as you start the job, and see how a brand-new disc cuts, and how quickly you can sand a given area. When you see that performance declining, and the time it takes to do a similar area starts to increase. change the disc.

In the end, it's more about feel and experience than any sort of real criteria, assuming again that we're not talking about discs becoming clearly clogged.

[Ric in Richmond]

I pass a SS wire brush against the face to clear off swarf that gets stuck, it only buys you a few more minutes though before it is done.

Ric

[Hirilondë]

Sanding a piece of rubber, like an old sneaker works quite well for loaded belt sander belts.

[Oscar]

And, save your coarse paper when done for non-critical operations requiring a finer grit.

[Robert The Gray]

great replies every one thank you all.

I thought it was sooner. it is just hard for the pack rat in me to throw all those seemingly usable materials away,
I shall be rigorous.


r

[bcooke]

So why would Robert be needing sandpaper if he sold his boat?...

[Rachel]

I am doing a refinishing project on a redwood deck.

Nice try though on stirring up rumors and speculation ;)