Microfiber Logic - Please explain

[bill57]

Before microfiber, we all used 100% cotton to buff our cars. I used clean old, tee shirts, sweat shirts, and the now-taboo terry towel. I always checked the label to be sure there was no polyester content, and on more than one occassion, I was tempted to use a soft, fluffy, garment that contained 30% polyester. But I relegated it to the shop rag pile because we would not dare want to rub a plastic thread against our car's surface.

Enter microfiber: the greatest thing since canned beer. So, I go with the "in crowd" and buy some. It's always bothered me, though, that the label reads "70% polyester, 30% polymide": PLASTIC! Regardless of the fiber diameter (or fractional mil), it's still plastic!

I don't understand the seemingly inconsistent logic. Please explain.

 

[imported_paradigm]

i believe it's all in how the fibers are cut/shaped/rolled...the base material may be a form of plastic, but its characteristics after processing is super soft and plush.

 

[Eliot Ness]

This article might help explain it:



http://www.autopia-carcare.com/inf-microfiber.html

 

[bill57]

Thanks, Elliot. I already had read the e-book. Excellent.

But I recently read a post on the Meg forum that had a certain brand of mf stating that if you use any other brand, no matter how soft it feels, you run the risk of scratching because it's plastic. That got me thinking again.

 

[Eliot Ness]

.......I recently read a post on the Meg forum that had a certain brand of mf stating that if you use any other brand, no matter how soft it feels, you run the risk of scratching because it's plastic. That got me thinking again.

If you're concerned, and you have every right to be when paint marring is at stake, then do the CD test with the MF's in question. Don't just rub them dry against a CD, but use a car wash solution, QD, etc. to test them under the actual conditions that you'll be using them.

In fact, most microfiber cloths that come from the orient are polyester microfiber and will most likely scratch the surface of your vehicle. Just because it says microfiber and it feels soft does not guarantee a scratch free shine!

The above quote is the one I think you're talking about from the Meg's forum. I feel the part of that quote in red might be a little broad, because I've had very good results from several of the well known suppliers of detailing MF's (from the orient): PakShak, Exceldetail, Sonus, Poorboy's, Premium Auto care, Autogeek, and SMP just to name a few.



I do agree with the part that says, "Just because it says microfiber and it feels soft does not guarantee a scratch free shine!" Not every towel made is safe for your paint, but if they pass the CD test then I feel pretty safe using them on my car. I also have some of the all cotton MF's from where that quote was taken and they are very fine towels indeed.



I just had some paint work done on my street rod and I had to wash, dry and glaze the fresh paint........ and none of the MF's I used, from the waffle weave to dry to the MF's I used to buff the glaze, left any marring. I'm sure there are plenty of cheap (and maybe not so cheap) MF's out there that will marr paint, but I try to stick with suppliers I trust and also test the MF's first to make sure they aren't going to damage (marr) my paint.



As to how they are able to make polyester, a fabric I hate, into a towel that absorbs and buffs so well I have no idea except it has something to do with how the yarn is made :nixweiss



Just my 2 cents on the subject.....

 

[the other pc]

It’s not just about the material's hardness but how the material interacts with the surface. A diamond is hard enough to scratch anything but if you lay one flat on paint it won’t scratch.



If you want to get all technical, scratching is a form of localized fracture and/or inelastic deformation, caused by applying a stress to the material that exceeds the material’s yield strength.



Applied stress can be thought of as a pressure, force over an area, as in “pounds of force per square inch.�



You decrease the pressure (stress) by either decreasing force or increasing the surface area over which it is applied.



You can increase effective surface area by applying force with fibers that deform under load (softer fibers), increasing the number of fibers that carry the load in a given area (finer fibers) or changing the geometry of the fibers to have a greater intrinsic interface area.



The synthetic microfibers we all know and love utilize fibers that are both finer and geometrically superior to the ordinary synthetic materials of the past (and most natural fibers).





PC.

 

[Accumulator]

the other PC- Great explanation :xyxthumbs



The "number of fibers" variable is, IMO why previously safe textiles can eventually start to mar paint...you lose fibers when you use/wash them and eventually the loss has a functional effect. We seem to assume that any degradation in softness comes from detergent/mineral residue (just look at all the threads about this) but sometimes you just need a new towel.

..do the CD test with the MF's in question. Don't just rub them dry against a CD, but use a car wash solution, QD, etc. to test them under the actual conditions that you'll be using them ..

Right idea about testing under the usage conditions, but I take a slightly diffent tack:



I only test my wash/QD media this way, as my other MFs will quite likely be used "dry". E.g., once my WWs have dried a surface they continue to contact the now-dry surface as I can't (or at least I *won't* ) discontinue all contact the instant the area in question is dry. With polish/wax removal MFs it's kinda the same thing, I can't assume the lubrication from the product will always be present.



So I test my WWs by drying a wet CD with them, using a wiping motion as opposed to blotting and I test my polish/wax MFs by rubbing against the CD with both dry. Admittedly, it'd be better to actually polish/wax the CD but I figure I'm just erring on the side of caution.



And even with the dry testing, plenty of MFs do not mar the CD.