7 inch angle grinder recommendations for Prep work

[NitroShark]

Starting my epoxy install and need to prepare the floor (good condition with no stains, 850 sq ft and 750 sq ft) , will do the floor in 2 separate installs/sections.

I’m going to use a industrial Tnemec coating system. 28-30 Mils, primer, base coat, flakes, clear and Poly top coat.

I bought a Dewalt 4597 grinder with their matching dust system including the HEPA concrete vacuum model DWV012. Any advice on using this combination? Will I still need to use an Edco grinder to do the main area? Or is it feasible to use the Dewalt.

I figure the edges will have to be done with a hand grinder but not sure if I can also do the main area. Maybe I will have more control over a floor model is what I’m thinking.

It does grind fast from my initial testing. I bought the Dewalt concrete diamond 4775 dual row cup wheel.

Any advice before I get started will be much appreciated….

Shawn

 

[bigbadktm]

I have done more floors with a 7" grinder than I care to remember. That setup will work just fine. Does the shroud have a flip up part on the front that exposes the cup? The shrouds that we use have that feature, and it is for getting up next to the wall while still having a functional shroud.

And that hoop handle on top will help with the digging in of the cup on the edges. With the side handle the grinder like to catch and dig grooves into the floor. All in all that looks like a pretty good setup.

 

[NitroShark]

Yes It Does Have A Flip Up Shield. Any Advice On Leveling Control Joints With It ?

 

[theoldwizard1]

You will have to stop and clean out that HEPA filter often.

Take it outside. Get "up wind" from some area that you don't care if it gets coated with concrete dust. "Reverse blow" using a leaf blower. Make sure you stay up wind !!

I can re-use fine particle filters after sucking up sanding from drywall compound several times.

 

[NitroShark]

Thing I noticed about the Vac is the suction was soo great (even on the lowest setting) that it was a little hard to "float" the grinder around. It works really well against the edges but was a little tricky to get it ground down flat.

Think I need to shim/space the wheel down more to lessen the vacuum sealing force? or what is the best way. Looks like the grinder wheel has some adjustment.

Shawn

 

[NitroShark]

You will have to stop and clean out that HEPA filter often.

Have you seen the video? The Vac has a pulse filter system...

http://www.youtube.com/watch?feature=player_embedded&v=t4spQH4pYQE

 

[bigbadktm]

Does the shroud have a cut-out in the top? The ones we use have a hole the size of a nickel in the top to facilitate air movement and keep the grinder from sticking. I like to use the figure 8 movement when grinding. How far off are your control joints that you need to level them? I usually start on the low side and jam the cup into the higher side, or run the grinder the length of the joint pushing more on the high side.

 

[NitroShark]

Good TIps Thanks.

The Joint Looks Like A Cross, With The High Spot In The Middle About 1/4 High. Dust Cover Does Have A Vent Hole.

 

[retfr8flyr]

What grinding disk are you going to use? I have used the grinding cups and I highly recommend getting the Diamana 7 inch disk. You will be amazed at the difference and with those size floors I would get an extra set of blades. Legacy Industrial carries them, as well as some other places.


Earl

 

[LegacyIndustrial]

What grinding disk are you going to use? I have used the grinding cups and I highly recommend getting the Diamana 7 inch disk. You will be amazed at the difference and with those size floors I would get an extra set of blades. Legacy Industrial carries them, as well as some other places.


Earl

 

[NitroShark]

What grinding disk are you going to use?

I bought the Dewalt concrete diamond 4775 dual row cup wheel. My first post list all the equipment I have now.

Shimming the wheel down (1/8 inch) really made a difference in suction and control. It is real tricky not to leave a "kiss" mark now and then. How much will they show up if less than say 1/32 deep?? Do I need to be sure to smooth them? that could leave a wavy floor?

Shawn

 

[pauls_workshop]

Hi Nitro, I did my floor using a 4.5" grinder and similar dewalt wheel. You don't want those kiss marks. 1/32" might not be noticeable, but 1/16 or more I would go back in after and fill in with some 100% epoxy patch and then grind over flat when dry. You don't have to or want to grind deeper when something gets messed up, just plan to pre-fill those areas with epoxy and white silica sand "mortar" in a 1:4 mix before your main floor coating is done. The silica sand will stretch the epoxy nicely this way. - Paul

 

[LegacyIndustrial]

Any mark, as you mentioned, will telegraph through the coating.

 

[retfr8flyr]

Get the Diamana tool and you will not regret it. Also you will be emptying the vacuum bucket a lot, with all the dust created grinding the floor and the size of that bucket.

 

[NitroShark]

Will getting a Diamana style tool Totally eliminate the possibility of grinding smiley faces or just lessen the fact ? Anybody have accurate dimensions of the wheel thickness so I can compare the fit.

Shawn

 

[Shea]

Will getting a Diamana style tool Totally eliminate the possibility of grinding smiley faces

Yes.

 

[retfr8flyr]

Will getting a Diamana style tool Totally eliminate the possibility of grinding smiley faces or just lessen the fact ? Anybody have accurate dimensions of the wheel thickness so I can compare the fit.

Shawn

Call Scotty at Legacy Industrial, he can answer all you questions.

 

[LegacyIndustrial]

Will getting a Diamana style tool Totally eliminate the possibility of grinding smiley faces or just lessen the fact ? Anybody have accurate dimensions of the wheel thickness so I can compare the fit.

Shawn

Shawn, the trick is to keep it moving.

Sent from my iPad using Tapatalk HD

 

[pauls_workshop]

With the regular diamond grinding wheel, you don't have to make any smiley faces. I had about 4 small ones on my whole project, but those were operator errors. If you keep the grinder moving back and forth and don't make any sudden tilts with it, you won't have any problems. If there are a few, I would just fill in with epoxy and grind over flat before the main coating - no big deal. You don't have to buy the much more expensive system above unless you want to, but apparently it does a good job, based on many inputs now on the forums. - Paul

 

[LegacyIndustrial]

We recommend a variable speed grinder for the Diamabrush.
This would help a cup wheel as well. Much more control when backed down a bit.

 

[pauls_workshop]

Has anyone tried to use a speed control in the circuit for an angle grinder to slow it down, like a router speed control? - Paul

 

[Smbarron]

Are you doing the whole floor with the grinder? How long does that take?

 

[NitroShark]

It's taking me about an hour or so per 100sq foot. I'm not sure if I should rent a Edco floor grinder or just keep doing it with the angle grinder.

One thing I notice is some spots are softer than others, some areas are harder than the back of Supermans head and take a lot more time to grind. Is that normal? will my profile suffer?

Shawn


..still got some stuff to move out.

 

[bigbadktm]

Completely normal to run into concrete that is soft in some areas and hard in others. As long as the finish looks about the same, you will be fine. Another thing to note is that a heavier broadcast of chip will hide lots of imperfections.

 

[NitroShark]

Thanks, everybody...

What are the indicators that the wheel is worn out? Seems like I am polishing and not grinding in some areas. Almost like the wheel is not cutting, not sure, could be hard concrete maybe?

Shawn

 

[NitroShark]

Help!


I'm finding some areas are grinding smother than others. It's a clean grind and really flat just not "rough" as other areas.

Seems like the "flatter" I get it the harder cured areas are coming out smother.

Will the Epoxy still "bite/adhere" properly......?


Shawn

 

[pauls_workshop]

Nitro, Edger here schooled me on this long ago. Your grinder wheel can get glazed over and needs to be roughed up a bit. You can do this by using some water and running it hard in the damp concrete just a few seconds every couple square feet. This will expose new diamonds and you should be good to go again. Polishing is not what you want. Harder areas will do this more readily than softer areas. I used some water on the harder areas when I did it. You will get a bit of slurry when you do that but that is what you have to do. You can get rid of the slurry later. - Paul

 

[NitroShark]

Ok Ill Try That...

What about a grinding Stone To Dress The Wheel? Aluminum Oxide Im Thinking..

 

[pauls_workshop]

Not like a normal grinder wheel. I don't think that would do anything for the diamonds. You could do a forum search for this but I can't recall which posting had it. There are videos on this phenomenon and what to do on this forum. Edger had these. Another case where we need some threads to be stickies or favorites of the forum please GJ but why never any stickies?? - Paul

 

[Shea]

Hello Nitro, I used to go to a softer cup wheel when hitting very dense concrete. The harder cup wheels will glaze and start to polish. Here is the link to Edger's site that explains what Paul is referring to as well as going to a softer cup. Glazed Diamond Segments

 

[NitroShark]

What I found out is the wheel was really loaded up. I tried both the water Tip and also use a Silicon Carbide dressing stone. Water worked good but I like the way the stone cleaned the wheel and it kept the vacuum dry.

I emptied the vacuum after about 5-600 sqft being ground and it worked great. I never saw any dust but still wore a high quality respirator.

Question I have is … I saw a few areas that looked like cracks but were not. The grinding brought them out. Are they OK to go ahead and prime or should I spot them with 215 surfacing epoxy?

Shawn

 

[pauls_workshop]

I would pre-fill those mini-cracks with epoxy or epoxy/silica sand mortar at up to 1:4 ratio for the bigger ones. Then prime and go forward. You can grind off for 1 second after dry to flatten with the surface before the priming step. Glad the water idea worked for you. The dressing stone is interesting. - Paul

 

[NitroShark]

7 inch angle grinder for Prep work- Install Completed

Looks like my work paid off finally…

Grind ( took 2 hrs per 100 sq/ft) , then started the application (took the last 6 days to do), 2 gal of leveling/surfacing epoxy, 12 mills primmer, 12mils color coat, 20 pounds flake, 12mils clear, 3mils poly urethane-, Done. Total 38mils

Used my racing weather station to send me updates every 5 minutes from the data recorder to be sure it all was timed out to the manufactures data sheets.

Should be fully cured tomorrow….. Got the other side of the shop to do now. 


Shawn

 

[retfr8flyr]

Looks great!! Isn't it a nice feeling when you finish and the results make it worth all the hard work.


Earl

 

[NitroShark]

Sure does, I'll try to get a picture of the final install posted.

 

[03ktmsx]

Starting my epoxy install and need to prepare the floor (good condition with no stains, 850 sq ft and 750 sq ft) , will do the floor in 2 separate installs/sections.

I’m going to use a industrial Tnemec coating system. 28-30 Mils, primer, base coat, flakes, clear and Poly top coat.

I bought a Dewalt 4597 grinder with their matching dust system including the HEPA concrete vacuum model DWV012. Any advice on using this combination? Will I still need to use an Edco grinder to do the main area? Or is it feasible to use the Dewalt.

I figure the edges will have to be done with a hand grinder but not sure if I can also do the main area. Maybe I will have more control over a floor model is what I’m thinking.

It does grind fast from my initial testing. I bought the Dewalt concrete diamond 4775 dual row cup wheel.

Any advice before I get started will be much appreciated….

Shawn

Shawn - Which Tnemec coating system products did you use - it looks like they have multiple products on their website - also what was the price per sq ft for all of the materials? Thanks.

 

[rburke65]

What is the purpose of the temporary posts therein the photos? Floor looks great! Thanks.

 

[NitroShark]

I'm installing a second Bendpak, so a post needed to be removed.

The system I used as follows:
1) Concrete Floors (Shop and Machine Area) (Decorative Flake Floor)

Surface Preparation: ICRI-CSP3. This is the scarification of the concrete to remove all poorly adhered laitance on the surface of the concrete and to provide a surface profile (I used a 7inch hand diamond grinder above). The floor was clean and dry prior to coating. Filled all control joints with Series 215 Surfacing Epoxy.

1st Coat: Series 201 Epoxoprime applied at – 12.0 dry mils
2nd Coat: Series 237 Power-Tread in 33GR Gray applied at 12.0 dry mils. While the coating is wet, broadcast random decorative flakes into the wet coating. (20 lbs)
3rd Coat: Series 284 Deco-Clear applied at 12.0 dry mils
4th Coat: Series 248 Everthane clear applied at 2.0 – 3. Dry mils

The application guide can be found here > http://www.tnemec.com/product/stratashield/ You can get data sheets for coverage also.

Since this is an industrial/professional product and not marketed for residential use, you will have to purchase it from thier distribution network.

It cost about $2sqft for the coating and about $800 for the Dewalt vac-grinder and wheel. Add about 3-400 for rollers squeegees and other Lowes stuff like buckets and paint poles/ LP gas for heating etc. About $3 a sqft I would guess.

Shawn