Bathroom tiling - regrouting - need Dremel tool with Cubitron for removing grout

[newbury]

For some odd reason my wallet has never wanted to release the funds to pay someone else to redo a bathroom, especially things like putting up small tiling projects. And I've generally gotten good reviews of the results.
But due to the pandemic my wife and I were gone from the house in Virginia for nearly 2 years and my son who was there apparently never remembered to clean the tile in the shower he used everyday.

We had in the past 30 some years just sprayed and wiped it down with no problem. However he let black mold start to live there and many of the grout lines which had been bright white turned black.

I've got most of it cleaned up with a combination of an oscillating/multitool and a manual tool but I really could use a bit for my dremel to "polish off". The other 2 tools often leave a stain of grout on the tile edges. I've been cleaning that off with 3M Cubitron and lots of elbow grease. I'm thinking a dremel with a conical bit of similar material would make it real easy,
Anybody know of such a bit?
/edit- sort of like a dentists buffing drill

 

[Gee Ray]

scrape it off with a razor blade. Using a buffing wheel sometime might damage the glazing on the tile.

 

[newbury]

This is on the curved part of the tile. Razor blade takes too many scratches. Manually buffing with the Cubitron just takes excess elbow grease.

 

[5030]

Cubitron?????

 

[newbury]

Cubitron?????

a 3m sandpaper type product.

 

[MossRoad]

a 3m sandpaper type product.

Never heard of it.

 

[Yander]

Cubitron.... Isn't that the planet the Transformers come from?

 

[5030]

Never heard of it.

Guess we learned something Mossy...

 

[jyoutz]

I’m wondering if a gel bleach would remove the mold without regrouting?

 

[Yander]

Have you tried this...

https://www.lowes.com/pd/1-Gallon-Liquid-Mold-Remover/3620698?cm_mmc=shp-_-c-_-prd-_-pnt-_-ggl-_-LIA_PNT_133_TS-Sanding-Sundries-Surface-Buckets-_-3620698-_-local-_-0-_-0&ds_rl=1286981&gclid=Cj0KCQjw4omaBhDqARIsADXULuXIuo1cHNapqqbgDyQl_YP0FeaQFyaAVNKy2t3yVVGEHQyUAHW2j_gaAs41EALw_wcB&gclsrc=aw.ds