Unigrit 3" Sanding & Finishing Discs

[Grifffx4]

How long do these discs last using a DA?

I use them for headlight restoration and I'm not sure when to dispose of each disc.

I usually use 1 3000 or 1000 finishing disc per pair of light before I discard.

With the sanding disc I use one per light before discarding.

Am I throwing money away?

[allenk4]

Are they clogging and then stop cutting?

[Grifffx4]

I can see the build up but I toss them because I'm unsure if they are cutting like the should even if I rinse them off.

I guess my question is does the grit wear off quickly or does it take a lot of abuse to use them up?

[SameGuy]

I find the 3000 Unigrit and Trizact both last longer than coarser discs. I can't do more than one lens with 320-1500 Unigrit or 2000 World Abrasives foil, but can easily do two lenses with either 3000.

[allenk4]

I find the 3000 Unigrit and Trizact both last longer than coarser discs. I can't do more than one lens with 320-1500 Unigrit or 2000 World Abrasives foil, but can easily do two lenses with either 3000.

Which grits are you using dry?

[allenk4]

I can see the build up but I toss them because I'm unsure if they are cutting like the should even if I rinse them off.

I guess my question is does the grit wear off quickly or does it take a lot of abuse to use them up?

You should be damp sanding with anything above P1000

Maybe you should try more moisture and spraying the residue off of the disc more often

[SameGuy]

320/500/800 dry. 1000 and above are wet. I normally don't use every grade, and don't always start at the coarsest.

[Grifffx4]

I find the 3000 Unigrit and Trizact both last longer than coarser discs. I can't do more than one lens with 320-1500 Unigrit or 2000 World Abrasives foil, but can easily do two lenses with either 3000.

Ok, that's what I am doing.

However I damp sand with all of them. 500/800/1000/3000

[allenk4]

I don't know if wet sanding is even suggested with the 500 & 800 papers

Are they waterproof?

Interested to find out

[SameGuy]

Yes they are. I've tried both ways. At low speeds on the GG3 the coarser ones don't need either the cooling or the lubrication, but it does keep dust down and cleans the medium.