ABRASIVES COMPARISON - multiple types, grits compared by 4 testers

[LGS]

I've thought of some other things that may help with the evaluation
1. Are all the Festool 150's the same? i.e. Are they all 150/3's or are there 5's and 3' mixed together. One would hope that a larger stroke would give a result different to a smaller stroke.
2. Are all operators operating at the same speed. If you are reviewing this data, you might want to check that. If you operate at a different speed, the results may not apply to your situation.
3. Since each operator seems to be using a different timber rather than a standard piece of wood, how will you achieve a test of reproducibilty? Also, one timber will probably affect the sanding pad differently to another. How can you compare apples to oranges?

That's enough for now I think.

[FenceFurniture]

It's not an attempt to get identical data from each tester, nor is it a laboratory test - it's all about what four different testers think of the different abrasives, and why they think that.

After all, woodworkers operate in different ways, with different timbers, with different sanders, to different levels of finish, with different pressures on the sanders, with different dust extractions systems, and so it goes on. BUT the abrasive manufacturer would like to sell their abrasives to as many different woodworkers as possible.

To follow your line of logic the tests would have to be done by (say) four different testers, on each of (say) six different sanders, on each of (say) four different species. That's a total of 96 different testers.

If someone wants to fund and organise all that, and then collate the data (kee-rist that would be a job) then they are very welcome to.

Just within my own testing (now ready to start the 320 grit stage) I'm seeing patterns emerge, some more definite than others, and where the patterns are closer together there are other factors which separate the different discs, such as purchase price and smoothness of operation. What I mean by that is that a consumer has to make one only choice when buying a brand of grit. They may choose to have different brands across the range in different grits (as I will) but i think it highly unlikely that an amateur woodworker would have two brands of 120, 2x180 and so on, just to suit subtle nuances. A handyman, on the other hand, may well have two types in the same grit - one open coat abrasive for paint, varnish etc, and a closed coat for timber. They never know what they are coming up against. They may even have a third type for metals for all I know.

There may be one or two exceptions to that at the ends of the grit range - e.g. I may end up stocking two types of 80g for two different hogging off purposes, and certainly at the very fine end I could very well end up stocking two brands of the same grits (in 800 upwards). This will depend on tomorrow's round of testing, but the Jöst "SG2" very fine grits are the same as the Platin 2 in that they are on 3mm sponge. You would be aware that this soft sponge will cause a very slight rounding over of edges even when used with a hard pad, which is sometimes not desirable. The other brands of very fine grits (including the Jöst ceramic on film range) don't have the sponge and I would anticipate that the sharp edge of the board will be retained.

So, all in all, there is other very useful information that is coming out of this testing, as well as the original goal of finding which are the durable brands in a price v performance situation.

I don't know about you, but I find the "jagging" (where the sander just wants to zip off in another direction - constant push and pull) of the 17 hole disc very fatiguing on a long sanding job. Towards the end of the job I find it downright aggravating (and have just done another 2.4 kilometres this arvo). That would be another separating factor, along with price.

EDIT: meant to say that there is one 17 hole disc brand where this jagging, although still present, as vastly reduced compared to two of the other brands. I don't understand it, I'm afraid.

[LGS]

Well said!

[FenceFurniture]

Well said!

¿Que?

I don't know about you, but I find the "jagging" (where the sander just wants to zip off in another direction - constant push and pull) of the 17 hole disc very fatiguing on a long sanding job. Towards the end of the job I find it downright aggravating (and have just done another 2.4 kilometres this arvo). That would be another separating factor, along with price.

EDIT: meant to say that there is one 17 hole disc brand where this jagging, although still present, as vastly reduced compared to two of the other brands. I don't understand it, I'm afraid.

What's your experience of this phenomenon?

[dalejw]

I think it's worth remembering here...

We're talking about sanding discs. The testing isn't on relative merits of expensive gear.

Accept the parameters of the testing, understand that it's not an exhaustive test performed in a lab environment, realise that it's going to be a least a bit subjective, take the information in good faith and move on.

If you've got good ideas about the testing practices, share them but seriously, if someone doing this testing rubs you up the wrong way.

Buy your own sandpaper and do the test yourself.

I for one, am very interested in the results.

[Skew ChiDAMN!!]

So, I dropped in on Brett t'other day for a beer and a story... and of course I had to poke around in his disks and take some for a test drive.

I think it's an understatement to say that I was favourably impressed with the results from some of the disks we played with. "Wow" is probably closer to the mark.

The end surface of the piece we were playing with ended up with a close to mirror finish using what, to me, was a ridiculously low grit. To achieve the same with my el-cheapo paper I'd have been up into my automotive wet'n'drys. Probably somewhere between 8k and 12k (depending on the timber, of course!)

I, for one, am definitely interested in Brett's final results. I thought there'd be some differences, of course, but this much?

[FenceFurniture]

Skew, I insist on accuracy in this thread.




It was 2 beers.

[Sawdust Maker]

Skew, I insist on accuracy in this thread.




It was 2 beers.

only 2?

Hah

anyway

to the testers undertaking this process - thankyou

[kikuyu]

Time to change sanding disk brands

Brett kindly sent me his first review. Very informative and interesting. It may be subjective and not 100% scientific as one poster said but so is wine tasting and its all useful information and good enough for me. Keep up the testing, very useful.From the information already, I will be changing over from my stock standard product from the Green Shed and going "up market" Happy to pay twice as much if the disks last three times as long. It has long been a source of annoyance to me that the disks I have been purchasing have to be changed every few minutes to keep the sanding process going at a reasonable pace. A little off topic, butI have been doing a little side reading on the health risks of dust and this tells me I should be using perforated disks and attach the vacuum hose!! I didn't even know that there are specific nasal cancers caused by wood dust inhalation. Duh, obvious when I think about it. With the amount of dust I have inhaled over the years its lucky I don't smoke. Time to be sensible.
Keep up the good work, I look forward to the next instalment

[FenceFurniture]

...I should be using perforated disks and attach the vacuum hose!!

Absolutely! You'll also find that the same type of abrasive discs will last considerably longer with DE happening. It prevents clogging of the abrasive face which creates unnecessary heat (which exacerbates the clogging even more, which creates more heat), and the clogging can prevent the abrasive being in contact with the surface to be sanded.

Also much quicker to clean up, tools and workshop don't get covered in dust.

Oh yeah, and you'll live longer!

[Sawdust Maker]

...

Oh yeah, and you'll live longer!

and thus will be able to make more sanding dust

[Bushmiller]

Brett

The initial testing on the coarse grits was most informative and quite a revelation. As you have said: Not what you were expecting. I'm looking forward to seeing the results on the other grits as they become available.

I thoroughly recommend anybody with even half an interest in ROS to request the results (which is done via a PM to FenceFurniture.)

Regards
Paul

[FenceFurniture]

I have now completed all the testing, and am finishing off the report.

This is the end product. Starting from a base scratch pattern from a new and particularly aggressive 80 disc, there was
10 strokes of 120 grit (a stroke is left and right combined)
9 strokes of 180 grit
5 strokes 240 grit
7 strokes of 320 grit
7 strokes 600 grit
Dust removal
8 strokes 800 grit
8 strokes 1500 grit
Dust removal
Brisk rub with White Spirits
8 strokes with 3000 grit
Brisk rub with White Spirits
Brisk rub with dry soft cloth

so a total of 62 abrasive strokes, and no other finish applied.

[crowie]

I have now completed all the testing, and am finishing off the report.

This is the end product. Starting from a base scratch pattern from a new and particularly aggressive 80 disc, there was
10 strokes of 120 grit (a stroke is left and right combined)
9 strokes of 180 grit
5 strokes 240 grit
7 strokes of 320 grit
7 strokes 600 grit
Dust removal
8 strokes 800 grit
8 strokes 1500 grit
Dust removal
Brisk rub with White Spirits
8 strokes with 3000 grit
Brisk rub with White Spirits
Brisk rub with dry soft cloth

so a total of 62 abrasive strokes, and no other finish applied.

Looks like a sheet of glass - brilliant job Brett....cheers crowie

[Simplicity]

That looks impressive Brett
Well done
Ps sorry but what timber did you use again
Matt