Refinishing and polishing quartz / granite kitchen worktop

[eyedee]

I recently bought a small off-cut of quartz worktop (40cm x 30cm odd) to use as a little shelf in a project I'm doing. It was the exact size I needed but was dull/unfinished and scratched on the face and sides. Local kitchen worktop fitters were all asking £100+ to refinish it, which seemed dear, especially as the finances have taken a considerable knock since Covid showed up. So after looking into 'how to polish quartz and granite' I purchased a diamond polishing pads kit (https://www.amazon.co.uk/gp/product/B08FQX4VLQ/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1) that was compatible with a standard drill and planned to bring the quartz back to a glassy shine this weekend.

The quartz was quite scratched in places but straight and true so I started with 600grit and worked through 1000, 1500, 2000 and finally 3000grits (all with a constant trickle of water courtesy of the garden hose). I did the top face and all four sides and was quite happy with the result until I got it inside the house and it thoroughly dried out at which point it was clear to see it is covered in fine circular scratches (clearly made by the diamond polishing pads) that create a matt haze. Bit disheartening but I'd like to carry on and get it finished properly with a glassy/glossy shine.

Did I just press too hard (I tried to simulate the weight of a standard grinder/polisher but maybe that was wrong) or is it something else?

I read (and watched on youtube) that quartz doesn't need any polishing compound to bring it to a shine and 3000 grit pads are perfect - but is this true? All the polishing compound products appear to be from the USA, which seems odd.

I thought maybe the diamond pads I'm using are the problem, but they do seem ok. They're not exactly flat unless a fair amount of pressure is applied to them, but I guessed that was normal?

Maybe I need an interface pad so pressure is less and more evenly spaced between the diamond pad and the quartz?

I'm at a bit of a loss as how to move forward, get rid of all the fine swirly scratches and achieve the glossy shine? I'm an absolute newbie to stone polishing etc and would really appreciate advice from those with experience.

Thanks

 

[Deleted member 174758]

I've done enough solid surface (Corian, etc) work in the past to maybe be able to understand this; when you change grits are you thoroughly cleaning the surface of ALL debris and contaminants and doing the same thing with the sander (pad)? Also are you sanding sufficiently long?

A common problem when polishing plastics and some soft metals is to leave some residue of a coarser grit on either the sanding backing pad or the material itself. That can cause the site of issues you are getting because the contaminant (old coarser particles of abrasive) will continue spreading the surface. Not sanding sufficiently and/or too great jumped.in the grits can also result in sanding Mark's not being taken out sufficiently. Of course, using a random or it sander would help reduce the swirl marks a bit as well, but that may be outside of your budget, and in any case stone sanding is reputedly very hard on the gearboxes of the tools