Diamond Cup Wheel Suggestions

[scottiem]

Well getting ready to start my garage flooring project and want to make sure I have all the necessary tools before I begin. Plan on renting a grinder to grind the floor but need to get cup wheel for my hand held to do the edges and areas that the floor grinder can't get. So I am looking for suggestions on which wheel to get. I have a DW 400 4 1/2" 5amp grinder and was looking at getting either the DAMO coarse 30/40 grit or medium grit 70/80 or the Dewalt DW4774 double row wheel. Also was looking at getting the DAMO 5" Metal dust shroud. The garage floor in question is a year old and in great shape just want to get it ready for epoxy. Not sure if my grinder will be strong enough for the job or should I get another one with some more amperage. Any help and info you could provide would be greatly appreciated.

Thanks
Scott

 

[pauls_workshop]

For just doing the edges and corners with a 4.5" hand grinder, probably any of those would work fine. You need a high power grinder only if you are trying to do the whole floor that way, which I did on mine to save cost. That should be fine for what you are using it for. The dewalt you mention is what I used on my whole project. It is very good. There are other choices too like diamabrush, but higher cost. The best cheap higher powered 4.5" grinder I found was a simple black and decker with 8.5 amps for about $30 or $40. Much better than anyone would otherwise expect it to be. Even more amps are good for full floor grinding use, but at higher cost than this for the grinder. Jump to the 7" sizes for 2 car or larger garage spaces if grinding with hand grinders to save time/effort. Also, use a dremel tool or multi tool with diamond coated bit on it to do the very corners even a 4.5" won't get or any other tricky areas you might have. Harbor Freight multi tool is fine and cheap (but loud!). Nothing beats a real Dremel as far as that goes, but I also use a corded Ryobi dremel version that is great and better for higher torque needs than a real dremel (uses very high speed but low torque to work). The 18 volt cordless super size dremel (more like a rotozip) from Ryobi is just awesome and one of their best cordless tools (unappreciated). - Paul

 

[scottiem]

Paul thanks for the info, I don't think I'll be doing the whole floor with a hand held as I have close to 900 sqft to do and I know my knees wouldn't be able handle that much time on them. If I decided to go with the DAMO wheel would I be better off going with the 30/40 grit or 70/80 grit as don't want to take to much off.

 

[dcs Inc]

I sell a bunch of cups and even though the more expensive V's and Z shaped segmented seem to be quicker the 12 segment turbo grinder on the 7" seems to best the best for the money. 30/40 grit, medium, medium/hard are the best sellers. The single and double rows cups tend to leave curf marks too easily. I usually push the double row segmented for the 4.5" as they are mostly used for touch up and not the main floor stuff. I have personally removed 900 sq. ft. in a day with a 7" on my knees (with a comfy knee board) I let the youngins do that **** now and run one of the large walk behind grinders I own. I think the premium 7" 12 segmented turbo cup sells for $60.00. I have to replace mine about every 10,000 sq ft. or so depending on what kind of **** I get into removing. It leaves a nice scratch pattern for epoxy.

 

[Edger]

You would be better off with the 70/80 grit because it will not take off as much as the 30/40. The quantity removed is determined more by the strength of the slab than the diamond grit size. Unfortunately you have no idea until you start grinding.

 

[pauls_workshop]

Listen to Gene at DCS or Edger! Again, for the little corners/edges, almost anything at all would be fine. I would go cheapest. It is actually possible to do 900 sq ft with a 7" hand grinder. People have done it like Gene. One day for that is pretty awesome speed actually. I did 250 sq foot with my 4.5" but took a long time to do, prob two full days or so over time. Prob the 30/40 grit for you, but you see it depends. For soft cement you want a hard wheel and for hard cement you want a soft wheel. The Dewalt is hard and works better on the softer cement, but also ok on the harder cement. Others are more specialized choices. - Paul

 

[ricky123]

Listen to Gene at DCS! Again, for the little corners/edges, almost anything at all would be fine. I would go cheapest. It is actually possible to do 900 sq ft with a 7" hand grinder. People have done it like Gene. One day for that is pretty awesome speed actually. I did 250 sq foot with my 4.5" but took a long time to do, prob two full days or so over time. Prob the 30/40 grit for you, but you see it depends. For soft cement you want a hard wheel and for hard cement you want a soft wheel. The Dewalt is hard and works better on the softer cement, but also ok on the harder cement. Others are more specialized choices. - Paul

Good job Paul ,Gene gave great info . Old Guy GE diamond Div. Retired

 

[LegacyIndustrial]

For those looking for a smoother grind, the diamabrush hand tool is really a dream.
One handed grinding and no kiss marks.

http://legacyindustrial.net/cart/hand-tool-for-removalprep-p-233.html

 

[pauls_workshop]

Good job Paul ,Gene gave great info . Old Guy GE diamond Div. Retired

Now modified post to say Edger too! Best grinding info sources on the forum I've run across, who I learned from! - Paul

 

[scottiem]

Ok well I checked with the local HD and to rent the Edco 10" is $80 for 8 hours plus $80 for the blade rental plus $40 for a commercial shop vac to use with it = $200 total. Either way I'll still have to buy a blade and dust shroud for my 4 1/2" hand held so would it be more beneficial to just buy a 7" hand held grinder, blade and shroud and bypass the Edco. When I do grind it I want to have it done in a day or 2 max. I could **** it up and do it on my knees if I have to but 30 years as an Aircraft Mechanic has taken it's toll on the knees. If I do go with a 7" grinder any recommendations on which one to buy, I'm not looking for the top of the line but I want something that will work well and last as I'll be doing my shop next spring after I get the garage done this fall. Again I thank you all for your input and patience as I want to make sure I do this right and don't feel like spending around $1500 on epoxy and materials just to have it go south on me. Also Gene any recommendations on a good knee board.

 

[dcs Inc]

I stock them from Marshalltown.
http://www.marshalltown.com/productDetail.aspx?prodID=16451

$14.00