Revision as of 10:05, 27 March 2021

Hint: Polished concrete is considered a green materials by LEED.

About and Materials

Orbital sander pads - [3]
Use 6 of these at one time mounted to a common bar, if you have open space to work with. Each is under 4 lb, so 24 lb total + mounting bar. 3A each for a total of 18A
- Hercules- [4]
- Bauer - [5]
- Performax - Menards $31 - [6]
Start with bulk grinding of rough spots - [7] - using a regular grinder:

Lessons:

collect dust, so you don't get larger abrasive spots from dust clumps
Go slow - pigtails will shrink
Calculations - if 15 seconds per foot, we have 39 passes lengthwise for one passthrough - meaning 1248 feet - meaning 5.2 hours per 500 sf pad. Save 20% by not doing under stairs and cabinets, you have 4.7 hours per pass. 5 sander gang gets that down to 1 hour. Definitely could use a holder for 6-10 sanders. If they can be ganged - that would be awesome.
Don't skimp on the grits - go up more slowly, which is actually faster.
Get the dust out - it clogs the sandpaper, and dulls it faster as you need to do more work
Get extra velcro pads
Store sander with pad on, so you don't flatten velcro hooks.

Good thread - [13]
Car polisher will work, and so will a variable speed grinder with diamond pads.
Get this grinder with variable speed can be found elsewhere cheaper. [14]. Pads - [15]. Pad holder - http://www.toolocity.com/4-back-holder-rigid.aspx
HF variable speed polisher 1 - $44 - 10A - [16]
High speed concrete/steel abrasive pads - 4" - only $6 for 5 - [17]
7" diamond pads are much more expensive - 800 grit for one - $30 - [18]
- 7 piece for $60 [19]
- $22 for one - [20]
- $30 for 1 - [21]
- $99 for 7 - [[22]]

Includes filling voids with epoxy binder + concrete, then sealer, then wax, and silicone between slabs to fill in cracks.

22", 12 pad sander - 500-1000 sf/hr rate - [23]. If there are 8 grind steps - that is a whole day job for 500 sf.
15 amp - 11" width. [24]

Throughout the process, a densifier is used to harden the concrete surface, which allows the concrete to be polished. A number of densifiers can be used; these consist of lithium, potassium or sodium silicates. In some cases, a grouting chemical is also used to fill in any holes, cracks or imperfections that were exposed from the initial coarse grinding step. The concrete can be also finished with a natural-look impregnating polish guard, which penetrates 2–5mm inside the pores of the concrete to prevent any deep staining from oils and spills. It is also breathable and not a sealer (as a sealer actually totally seals the concrete and does not allow vapor transmission). -[25]
If you just grind, no polish - you can use sealer - but then it won't be the natural shine that is obtained from going to finer grit.
Discovered only in the 90s?

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+=About and Materials=
 *Pads - [https://www.homedepot.com/b/Tools-Power-Tool-Accessories-Abrasives-Polisher-Accessories/Con-Flex/N-5yc1vZc8yeZmmx?storeSelection=]
 *Amazon - [https://www.amazon.com/Diamond-Polishing-Granite-Concrete-Marble/dp/B071ZTFYYX/ref=sr_1_11?ie=UTF8&qid=1503952899&sr=8-11&keywords=concrete+polishing+pads]. Hook and loop means velcro attachment of pads.