How many holes in sandpaper is enough?

[duburban]

Just took a look at this new Multi Jet Stream 2...

At what point do we just use vacuum air to abrade the wood surface and dispense with the sandpaper all together?

I'd like to see some real hard justification for that many holes in the paper. I'm a little confused because I assume the paper is cut for dust extraction after the sheet is made so its not like anyone is saving a ton of money on grits.

Anyone have any miracles to share with this lacey new sandpaper?

 

[yetihunter]

I'm more curious about the decision to begin distributing abranet (which requires a pad protector on Festool pads) at the very same time.  I mean, it's great for heavy Festool dealers that have a weekly order.  Mirka supplies are always spotty, locally.  I don't mean to bite the hand that feeds.  However, I have to imagine it's confusing for customers.

Norton has sandpaper with 8 thousand jilliony laser cut holes.  I ended up with some, I did not notice a difference.

Anyway, it's backwards and forwards compatible, so I don't care either way. :0

 

[JFelchlin]

My three “older” Festool Sanders (see my “signature”) have always sanded just fine -
With the dust being extracted quite adequately from “fewer” holes.
Just a thought:
If MORE holes are cut in the paper BEFORE the grit is applied -
Could it be that selling “air” (holes) is more profitable than selling actual “sandpaper”? [unsure]
Unheard of?
I remember when Dog Food companies injected WATER (40% of the package weight) into dry dog food -
And sold it as “Moist Dog Food” - At 25% more in price than the “plain” dry dog food.
And... People bought it... For a while.

 

[AlexThePalex]

When Festool went from 8+1 to 8+8+1 I did see a small difference though it was hardly noticeable, but beyond that, no difference whatsoever.

I see a trend with all sandpaper manufactureres to put more and more holes in their paper, as if it's a weapons race, and I think it's all non-sense.

 

[Michael Kellough]

About 20 years ago I had a project that required dead flat sharp edges. The grain was too squirrelly to use edge tools so I used the 3M Stikit psa abrasives on straight strips of pvc as sanding blocks. Quickly learned that with no give in the abrasive that dust piled up and not only prevented the abrasive from making full contact with the work but also threw off the co-planer relationship of the sanding block to the work defeating the purpose.

The solution was to use small strips of abrasive separated by small gaps to allow dust to move off the abrasive surface. The more strips and gaps (per area) the better. Also, the gaps needed to be scaled to the grit. Bigger gaps for coarser debris. And it helped if the strips/gaps were angled relative to the stroke direction. Dust piled up in the gaps less as it ran off the edge more.

Based on that experience I think the most productive form of rotating abrasive would have a radial abrasive stripes scaled to the grit size. The spiral pattern oriented to pull dust in to the evacuation holes rather that throw it outboard.

I think the trend toward more holes in abrasive disks confirms my experience. Broad areas of abrasive allow dust to accumulate and are counterproductive even if that seems counterintuitive. On the other hand, I think the net abrasives go too far with too little abrasive making contact with the work. Maybe when Mirka began producing that form of abrasive it made sense from a manufacturing point of view but there are other ways to pattern abrasive now. 

In my opinion, Norton’s ProSand Multi-Hole Cyclonic Disk’s are just about ideal. The small holes also allow the disks (which have a nice soft conformable backing) to be used by hand with much less risk of snagging a hole on a corner of the work.

PS  I’d have a more difficult time finishing that project from 20 years ago now because 3M stopped making Stikit psa abrasives on rolls. The “similar” products available now are not as good. Between the inconsistencies in abrasive application, adhesive application, and maybe even backing thickness, the available psa abrasives just don’t cut evenly.

 

[ben_r_]

Ha! I thought the same thing the first time I saw the Multi-Jetstream 2 pads! Especially since Festool already has the best dust collection ROs on the market with the Multi-Jetstream 1! On TOP of that, as it was many instances require a CT vac to be turned DOWN in order to avoid producing too much suction and sticking the sander to the workpiece. So now with the Multi-Jetstream 2 does that mean the vac will have to be turned down even more now?! Either way Ill be sticking with my Multi-Jetstream 1 pads and discs as long as I can. I see no real reason to upgrade especially seeing as how the Multi-Jetsream 2 discs will work with the Multi-Jetstream 1 pads.

 

[duburban]

About 20 years ago I had a project that required dead flat sharp edges. The grain was too squirrelly to use edge tools so I used the 3M Stikit psa abrasives on straight strips of pvc as sanding blocks. Quickly learned that with no give in the abrasive that dust piled up and not only prevented the abrasive from making full contact with the work but also threw off the co-planer relationship of the sanding block to the work defeating the purpose.

The solution was to use small strips of abrasive separated by small gaps to allow dust to move off the abrasive surface. The more strips and gaps (per area) the better. Also, the gaps needed to be scaled to the grit. Bigger gaps for coarser debris. And it helped if the strips/gaps were angled relative to the stroke direction. Dust piled up in the gaps less as it ran off the edge more.

Based on that experience I think the most productive form of rotating abrasive would have a radial abrasive stripes scaled to the grit size. The spiral pattern oriented to pull dust in to the evacuation holes rather that throw it outboard.

I think the trend toward more holes in abrasive disks confirms my experience. Broad areas of abrasive allow dust to accumulate and are counterproductive even if that seems counterintuitive. On the other hand, I think the net abrasives go too far with too little abrasive making contact with the work. Maybe when Mirka began producing that form of abrasive it made sense from a manufacturing point of view but there are other ways to pattern abrasive now. 

In my opinion, Norton’s ProSand Multi-Hole Cyclonic Disk’s are just about ideal. The small holes also allow the disks (which have a nice soft conformable backing) to be used by hand with much less risk of snagging a hole on a corner of the work.

PS  I’d have a more difficult time finishing that project from 20 years ago now because 3M stopped making Stikit psa abrasives on rolls. The “similar” products available now are not as good. Between the inconsistencies in abrasive application, adhesive application, and maybe even backing thickness, the available psa abrasives just don’t cut evenly.

I appreciate this scientific information BUT... what was the nature of this project with these meticulous constraint?!

 

[Cheese]

...so I used the 3M Stikit psa abrasives on straight strips of pvc as sanding blocks.

Still interested in 5” diameter Stikit abrasives? I have a roll of 200-300 of them in 400 grit that have your name on them from my indentured servant days at Mother Mining.

 

[ScotF]

When Festool went from 8+1 to 8+8+1 I did see a small difference though it was hardly noticeable, but beyond that, no difference whatsoever.

I see a trend with all sandpaper manufactureres to put more and more holes in their paper, as if it's a weapons race, and I think it's all non-sense.

I agree...

 

[Gregor]

The upside seems to be that the new pads also add suction to the side of the disk (through the outward channels on the pad) which should help picking up dust that escapes from under the pad.

Also more holes = more even extraction = more even cooling of the pad = less hotspots/melting = longer lasting paper.

Havn't seen these live so far (as my supplies of the old style still last), but in theory the new pads/disks look like a sound idea.

 

[Michael Kellough]

[member=12487]duburban[/member] it was a sculpture project. Not mine and I don’t have pics readily available. Somewhat counter-intuitive, but minimalist art is more painstaking to produce, especially when it has to conform to a concept of pure geometry.

 

[Stone Message]

Just took a look at this new Multi Jet Stream 2...

At what point do we just use vacuum air to abrade the wood surface and dispense with the sandpaper all together?

I'd like to see some real hard justification for that many holes in the paper. I'm a little confused because I assume the paper is cut for dust extraction after the sheet is made so its not like anyone is saving a ton of money on grits.

Anyone have any miracles to share with this lacey new sandpaper?

I have not tried the new paper/pads yet but I made a very brief video of it in action sanding drywall - watch to see if any dust escapes:


Peter

 

[Naildrivingman]

I’m gonna go with Niles’ quote from the TV program Frazier...

“If less is more, think how much more, more would be...” [scratch chin]

By no means can I weigh in on this to any extent, but I see both sides of this. Dust extraction is great for the health of all concerned (including the paper itself), I also wonder if (more) dust extraction doesn’t compensate for less than adequate techniques.  I watched an FT video on sanding and while I am not a furniture maker I do have to achieve a level of smoothness to my product.

That video presented a number of techniques that I have not employed. It makes me wonder if greater dust elimination compensates somehow for poor technique. For example, in the past I used far more down pressure than I should. This is one part of my technique that I have changed.

@peterparfitt video displays that even the finest dust (drywall) can be collected quite well with earlier generation pads and paper.

 

[Stone Message]

@peterparfitt video displays that even the finest dust (drywall) can be collected quite well with earlier generation pads and paper.

No that was the new paper and pads in the video - a completely different result than could be achieved with the old style paper and pads.

Peter

 

[leakyroof]

I’m gonna go with Niles’ quote from the TV program Frazier...

“If less is more, think how much more, more would be...” [scratch chin

I had forgotten that Line.... [thumbs up] [thumbs up] [doh]

 

[peter halle]

I don't care how many holes the sandpaper has as long as it picks up the dust.  If more holes equals less dust - Great!  Companies are not spending development dollars to increase holes and decrease grit.  The disks are made whole and then the holes are die cut.

Peter

 

[Naildrivingman]

@peterparfitt video displays that even the finest dust (drywall) can be collected quite well with earlier generation pads and paper.

No that was the new paper and pads in the video - a completely different result than could be achieved with the old style paper and pads.

Peter

Im terribly sorry for misrepresenting you, Peter.  I only watched the video once and I thought you had referenced you were using earlier generation equipment.  I absolutely did not intend to suggest anything false.

I do enjoy your tutorials.  Please keep up the good work.

Best,
Chris

 

[Stone Message]

Hi Chris

No problem - I think that I could have been a little clearer.

Anyway, the new stuff is brilliant (sic) and when I have worked my way through my stock of the original (mainly Granat) I will get the new pads and paper. I also want to try the mesh abrasive as that looks pretty good too.

Peter