First-timer with grinding question

[XHDad]

I'm about to hand grind my 425SF garage floor in preparation for epoxy coating. I needed an angle grinder, so I bought one with the Diamabrush hand tool. Of course I have questions...

The Diamabrush rep said that the tool operating at 11,000 RPM would be plenty to cover the surface I have. When attaching the tool, I noticed that it didn't completely screw into the grinder itself. Is this normal, and is it dangerous?

I am also planning to wet grind the floor as I can't find a great option locally. Any tips for wet grinding by hand?

I appreciate the assistance!

 

[Dick in Wisconsin]

Are you going to grind the 425sf floor with an angle grinder?

 

[XHDad]

Yes, that's the plan. I put the Diamabrush hand tool on the spindle, but it only appears to go about halfway on. It seemed secure when I powered up the angle grinder.

 

[Dick in Wisconsin]

Have you considered renting a floor grinder at HD and the big Diamabrush pad?

When I put my Rust Bullet down, I had 1000sf to grind. Rented the bid floor grinder and big pad. Bought the small pad for the edges, but that was so awkward to us I gave on the edges and used the bid floor grinder and bid pad to get as close to the edges as possible. Left a a little "sealer" on the concrete around the edges. Rust Bullet sticks to it 15 months later with apparently NO problem.

I ended up grinding my floor twice with the big machine to get all the sealer off. Having done that ... I would probably rather eat bees than to grind 425sf with a handheld angle grinder.

Does it wobble or is it loose when you grab the Diamabush and try to wiggle it? (pull plug first!)

 

[CombatNinja]

You are insane if you are planning to grind 425 sq ft with a handheld angle grinder.

 

[chrispyny]

I JUST ground down my two car garage with a diamabrush and clarke buffer i rented from HD.

DO NOT try grinding 400+ sq ft with an angle grinder. Please. Save your back. Plus it will look like pure poop.

I'm doing armorpoxy when it comes in next week. Will do a new thread from beginning to end.

See?

 

[gregtwojeeps]

There are 3 types of men. Those that learn by reading. Those that learn by observation. Those that piss on an electric fence to see if it really works.

 

[Shea]

There are 3 types of men. Those that learn by reading. Those that learn by observation. Those that piss on an electric fence to see if it really works.

OMG... I just about spit my coffee out!

OP - If the Diamabrush attachment turns a full 3 or 4 turns on the arbor then you should be fine. If you have the 7" Diamabrush you will be able to do your entire floor.

However, the advice you are getting here is pretty much right on point. For around $100 you can rent the bigger Diamabrush on a floor maintainer and get the job done much faster and while standing up as well. Wet grinding is messy enough and I could not imagine doing it on my knees. You will also need to purchase a fault circuit interrupter (they come with the floor maintainer rental) or you will run the chance of being like the guy above ******* on an electric fence.

I suggest you read this article about grinding garage floors. It covers how to wet grind as well.

Good luck!

 

[James-W]

There are 3 types of men. Those that learn by reading. Those that learn by observation. Those that piss on an electric fence to see if it really works.

That was pretty graphic. i could actually envision that happening, not to me, to somebody else.

 

[XHDad]

Fair enough. I had to buy an angle grinder anyway, so I hoped it would save a few bucks... but not at the expense of doing it poorly.

Shea, thank you for the link.

 

[Dpmulvan]

I just got done grinding 700sqft garage with a harbor freight 7 inch grinder, diamonbrush and a homemade dust shroud made out of a Tupperware microwave plate cover (to warm up leftovers). Bought a dust deputy which your going to need along with at least two vaccum filters. It didn't take long and came out great. I was going to rent the unit but all their diamonbrush blades looked like **** at Home Depot. It's really not that bad, let the tool do the work. It took me two days along with filling cracks and using Ardex cd on the spalled area.

 

[Dick in Wisconsin]

Keeping the small diameter Diamabrush level with the floor while working on your knees is what the challenging part will be. Get it at an angle once or twice and you'll quickly have a deep gouge in the concrete and be unhappy.

 

[Gozo]

Keeping the small diameter Diamabrush level with the floor while working on your knees is what the challenging part will be. Get it at an angle once or twice and you'll quickly have a deep gouge in the concrete and be unhappy.

What **** said. I did sections where I needed to level or grind down filler with a cup wheel. Keeping it level was essential. Wound up making a fixture to help with this. See the picture in my post of my adventures.
http://www.garagejournal.com/forum/showthread.php?t=222319
BTW - stills great after a few years.

 

[Dpmulvan]

I had no problem with the 7 inch diamonbrush I guess it depends on your floor and concrete. I also skipped the epoxy, too costly and not good for rolling jacks et. I went with a Zylene based opaque stain. $230 for 5 gallons. You must keep doors open and wear a respirator some nasty stuff!! You can get it at Sherwin Williams it's called hc topcoat.

 

[Dick in Wisconsin]

I had no problem with the 7 inch diamonbrush I guess it depends on your floor and concrete. I also skipped the epoxy, too costly and not good for rolling jacks et. I went with a Zylene based opaque stain. $230 for 5 gallons. You must keep doors open and wear a respirator some nasty stuff!! You can get it at Sherwin Williams it's called hc topcoat.

How long ago did you put on? What does your floor look like? Can you post a picture?

 

[Dpmulvan]

Put it on two days ago after months of research and speaking to a high school buddy who has made millions doing floors for commercial buildings, car dealerships, factories et. Originally I wanted epoxy but decided against it seeing as how I will be using my garage to restore a cars et. Welding, rolling jacks, winter salt, et where the reasons I went with the product I did. Don't get me wrong epoxy looks great especially with Quartz or flakes done to full refusal but the cost to do 700sqft properly was more than I wanted to spend. You also have to be careful with all these companies who have popped up selling sub par products with unrealistic sqft coverage claims. Actually I found out the best top of the line epoxie's are not even available to the general public. Anyway I'll post some pics this afternoon.

 

[Dpmulvan]

First time uploading photos on this site hope it works.

 

[Dpmulvan]

Sorry about crappy photos. Ground floor,chased and cleaned cracks, applied epoxy with sand into cracks. Applied Ardex cd fine to spalled areas (most of floor) great product!!! Ground everything smooth applied two coats, second coat used shark bite in the mix.
Total cost: 700sqft
Harbour freight 7 inch grinder $35
Diamonbrush $85
Homemade dust shroud $4
Homemade dust deputy $7
3 vaccum filters $60
Epoxy for cracks $60
3 bags Ardex cd fine $120
5 gallons opaque Zylene based concrete sealer $180 40% off would have been $240.
1 bottle shark bite $15
One respirator $30

 

[bjsbuds]

Sorry about crappy photos. Ground floor,chased and cleaned cracks, applied epoxy with sand into cracks. Applied Ardex cd fine to spalled areas (most of floor) great product!!! Ground everything smooth applied two coats, second coat used shark bite in the mix.
Total cost: 700sqft
Harbour freight 7 inch grinder $35
Diamonbrush $85
Homemade dust shroud $4
Homemade dust deputy $7
3 vaccum filters $60
Epoxy for cracks $60
3 bags Ardex cd fine $120
5 gallons opaque Zylene based concrete sealer $180 40% off would have been $240.
1 bottle shark bite $15
One respirator $30

I would like to hear more about your project, as I have 1,400 sq ft to cover and epoxy is pricey. I searched Sherwin Williams' web site for the concrete sealer you used. Can you be more specific abut the name of your product; was it H&C Clarishield oil-based sealer?

How about shark bite, was it H&C Sharkgrip?

 

[Dpmulvan]

Shark grip, yes sorry.