7" angle grinder

[ning]

I'm quite the amateur and I'm wondering at what the 7" (and 9"!) grinders are typically used for.
I've got three 4 1/2" grinders that get a lot of use, but I've never been exposed to a 7" and I tend to make do with what I've got unless it flat-out doesn't do the job, or someone educates me, and since my old mentor-neighbor died a while back, I don't get much of an education other than what I get off the web.
So, web, tell me why I need a 7"

 

[spitter]

How much material u want to remove and how much power u need are some good reasons for going from a 4 1/2 " grinder to a 9". 41/2 are usually 4 or 5 amp 9 " are 15 amp . Go on the metabo website and look how many grinders they make ranging from lite duty 7 amp to 14 amp .In all sizes 4 - 9 , you wouldn't want to use a 14 amp 5 " grinder made for concrete diamond wheels to remove rust or paint all day . The weight difference is a few pounds between 7 amp and 14 amp. If u put a diamond wheel in a 4 1/2 " 7 amp grinder and tried to cut concrete it wouldn't last a day. Match grinder power to job. :drink:

 

[Bird]

I'm quite the amateur and I'm wondering at what the 7" (and 9"!) grinders are typically used for.

I'm not sure exactly how they were used, but the Sioux tools I dealt with were very old and were used by one of major trucking company's "trailer rebuild shop".

 

[Soggy Bottom Outdoors]

No real agreement here. But I've used a lot of Dewalt stuff and had good service. Lookin' at model DW840 I think. I also have several Bosch tools, like a sawz-all, that has gone above and beyond. Lookin at model 1974-8. About a $60 price difference. Mostly used on old broken farm equipment farm equipment.

 

[Fallon]

I got my 9" HF to finish a cut through concrete that was thicker than expected. Didnt want to rent a real concrete saw & needed the bigger blade for an inch or 2 more cutting than what I got out of the diamond blade on the circular saw.

Use it for bigger grinding jobs on steel mostly now.

 

[Sebculb]

I'm quite the amateur and I'm wondering at what the 7" (and 9"!) grinders are typically used for.
I've got three 4 1/2" grinders that get a lot of use, but I've never been exposed to a 7" and I tend to make do with what I've got unless it flat-out doesn't do the job, or someone educates me, and since my old mentor-neighbor died a while back, I don't get much of an education other than what I get off the web.
So, web, tell me why I need a 7"

I don't actually use the big grinder for that much metalworking. 9" diamond blade is terrifying but works well for cutting concrete and rock.

Put a sanding disc on it for fast wood removal sanding in rustic carpentry. Belt sander can't compare. Belt Gives cleaner results but three days into sanding a new cabin out in the woods you might reach for the disc.

And sometimes with metal, for big metal or a lot of metal or a lot of grinding, the bigger tool is faster and takes the abuse better.

I have a DeWalt 9", put 7" on it sometimes. 9" is lower rpms so better for sanding wood and the bigger blade capacity is good for concrete. Works well, good quality so far.

 

[yomax4]

I have an old orange HF grinder and it's still grinding. I won't tell how I remedied the problem when the switch went out as it's probably unsafe and will kill me sometime soon.

Ha, I did that with their POS SawzAll

 

[dragoneggs]

I still crack up when I read Hp ratings. The Bosch may be the cat's meow but they advertise 4hp. Huh??? I love Bosch but com'n man!

120v machine at 15amps is 1800watts. Equals 2.4hp. Please explain.

1974-8 | 7 In. 15 A High Performance Large Angle Grinder | Bosch Power Tools

 

[Redlands Okie]

Got a Milwaukee that has ground a LOT of concrete floors the last couple of years and a fair bit of metal. Holding up nicely.
Dewalt would be my second choice of brands.

Matebo, Bosch, Mikita all are known good brands

 

[stuckmotor]

Has anyone ever used the replacement brushes that come with the power tools? If I have, it was only one time and I don't remember for sure.