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Hard resin flooring showing fingernail scratches after polishing (video)

4505 Views 6 Replies 5 Participants Last post by  Taranis
I'm doing something a bit different on my current project and I don't specialise in flooring, but I'm trying to develop my own thin "pseudoterazzo" floor made from resin, decorative sands and fillers trowelled onto the slab, which then gets polished with resin pads like a concrete floor. I'm having this problem where after grinding and polishing it, despite it being very hard and incapable of being scratched with even metal, my fingernails are able to mark it. Other surfaces of similar hardness don't do this and I can't figure out what these marks actually are. I tried wiping it down with various chemicals, even acetone in case the surface is actually covered in remaining resin. Even polishing it only with metal-bond pads created this effect.

My possible theories as to what this is are that it could be
-parts of the resin pads smeared on the surface of the floor when when rubbed distort and create a "scratch"
-organic material from my fingernail filling in the porous surface (currently checking if a penetrating sealer solves this)
-a sheet of "burned" flooring resin glazed over the top as a result of the polishing process which isn't as strong at the flooring itself (although I tried wet polishing it and still had the same problem)

This doesn't seem to happen on any other surfaces, even those of similar composition such as manmade stone benchtops, marble, or polished porcelain tiles. The thing I don't understand is that although the surface is extremely hard and resistant to mechanical scratching, my fingernails are able to leave marks.

Strangely enough, the marks buff right out again, more easily with water, which leads me to think that it's only my fingernails leaving organic trails.

This could be something really obvious but I don't specialise in flooring and I'm developing this system because I'm not aware of anything similar commercially available.

If you know what these marks are, please let me know.

Here is a video of the problem.

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Your video doesn't show me that you tried scratching it with metal, so I have a hard time believing that metal does not scratch it even though your fingernail does, although it is possible your fingernail is leaving something behind rather than taking something off. Try some other materials to scratch the surface. A plastic trowel. A plastic knife.

Maybe your fingernails are made of some strange material not known on this planet. Are you an alien?
See if a wax pencil leaves a mark.
Looks more like oil from your finger to me. Rip off one of your finger nails and hold the free nail in vice grips and try to scratch the floor.

Please post a video for this procedure as well. For evidenciary purposes.
Seems like a penetrating sealer, which has now dried, has helped a fair bit. I'm guessing it was simply fingernail rubbing off into the unsealed pores.

A key or piece of metal simply leaves a grey mark which can be cleaned off with acetone. There is no real mechanical scratch.

The material is a similar composition and hardness to artificial stone benchtops.

I'm wondering if I should seal after the initial grind and then polish off that.
My last post wasn't quite on track - the sealer didn't really have much of an effect.

It turns out the problem was that the resin itself wasn't properly polished, and the "polish" was simply buffed residue on the surface. I polished it again more thoroughly with the lower grit pads and then redid the final polish, so that the material itself shines rather than a buff that sits on top.

I thought I'd add that in case anyone is curious or runs into similar problems.
"This could be something really obvious but I don't specialise in flooring and I'm developing this system because I'm not aware of anything similar commercially available.

If you know what these marks are, please let me know."

There are loads of resin terrazzo products available, a quick search on this site will even show you some. They have been used for a long time.
Why not find out who in your area produces them, buy some and use the manufacturers/contractors expertise and experience to install this product. Resins aren't for the uninitiated.
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