Acid etch necessary after grinding or shot blast (epoxy coating)

[upjeeper]

Acid etch necessary after grinding or shot blast (epoxy coating)?

3 years ago we coated our garage floor with a cheaper product from Home Depot

Now the coating is peeling up, is quite dull in many places and just doesn't impress me. So I'm in the process of replacing it.

I'm planning to go with Epoxy Coat or Legacy Industrial (want to use a quality product).

I've got quotes to have it shot blasted, but I'm still toying with the idea of using a grinder.

As far as I know grinder and shot blasting will both do a very good prep job, but do I need to acid etch also?

 

[LegacyIndustrial]

Jeeper:

The grinding or shot-blasting is all you need.
Either of these (2) processes will create a suitable profile and remove laitance from the substrate.

 

[Edger]

You should think of acid etch as a second cousin to grinding or shotblasting only to be used when professional equipment is unaffordable, a DIY preparation method. Grinding or shotblasting is superior.

If you have paint on the floor the shot blast may leave an uneven surface profile because it takes longer to remove some existing paint and the adjacent areas where the paint comes off quickly get a stronger profile from blasting. This effect is multiplied if your floor is a little on the soft side and you should allow more epoxy than for a smooth floor.

Diamond grinding will leave a flatter profile, will require less epoxy to cover, but you may expose small air holes that result in little bubbles in the wet epoxy if applied on a hot day.

 

[LegacyIndustrial]

Good points Edger.

I'd also like to add that Legacy Industrial has added some economical options to help those who want a quality coating system but can't afford a top of the line kit. Link:

http://legacyindustrial.net/cart/garage-floor-coating-kits-c-51.html