Amp rating on grinders

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So I burned up the brushes on my HF "Blue" 4" grinder, or is it 4 1/2"?  Anyway...  I need a new one.  I use a 7" for my heavy grinding, but use the smaller one for cutting, light grinding, and the occasional twisted braid wire brush.Look at several models:  HF has the "orange" on with 4.5 amp, Northern has an 8 amp model, and Milwaukee has a 10 amp.  Based on what I stated that I use the smaller grinder for, would the HF do ok?  Or, should I fork out the $100 for the Milwaukee, knowing it is way more amps than I need, but a better quality build?
Reply:You get what you pay for. I've owned DeWalt, Black & Decker, Craftsman, Makita and Chicago Electric. I've burned them all up (head bearings, I get them in a bind!) over using them instead of my 9". Amps makes a big difference in power, and that translates into longer use. I'm currently looking at a 4 1/2" Makita simply because it is AC/DC and has 10.5 amps.Only when the last tree has died and the last river has been poisoned and the last fish has been caught will we realize we cannot eat money.                                         -Cree Indian ProverbSA 200 LincolnVictor Torches
Reply:Amps are what its all about to me.  I have had a few.   Makita 5 amp..... DogHarbor freight has NO BALLS.  I find 9 amps to be a good base line.  I tend to lean on the grinder to make it work and earn its keep.  I have only burned up a couple of grinders, but the ones with over 10 amps get the job done the fastest.I don't especially like grinding with a tool that stalls when I push on it, so I buy the bigger amp ones.  I had 2 dewalts that are 11 amps and I burned one up from stalling it.  The other one I still have and like the best.  I just bought a 13 amp dewlat 4.5 or 5" that I can't comment on because I have only used it a few times.I also buy the good wheels that cut when expected to.  They do wear out faster sometimes, but I want to get the metal off, not save $.50.David Real world weldin.  When I grow up I want to be a tig weldor.
Reply:Put the flap wheels and small wire cups on the low powered HF units. Leave the grinding wheels to 8 amps and up. Even then you might cook a HF unit bearing down heavy on a wire cup for long stretches of time. I did anyway.
Reply:We have an unbelievable tool store in Derby KS.  I went to get a grinder.  It was between the Milwaukee and the Makita.  I did not like the Mil.'s trigger and locking mechanism.  I knew I would break it. So I got the Makita. It is a 5" (with the guard on hehe) 12 amp motor. The thing is a horse yet slim and compact for cutting. Has a handle for grinding and I love the thumb switch because you dont have to hold it on. It also has variable speed (yeah I know) but I didnt care about this......untill I bought a 5 inch polishing pad and use it to polish horse trailer aluminum trim. I paid 171 for it. They had a 10 amp without variable speed for 121.  My Dad just bought a Dewalt 6 inch 10amp and loves it.
Reply:These are what I use.  Cheapo with a flap wheel and Black and decker with the cup brushes and stones.  The Black and Decker only cost me $25 a couple of years ago and it came with an extension cord, so it was a good deal.  It's only 6.5 amps but has yet to dissapoint me.  We had 11amp dewalts at work to compare to.  For grinding stones I like the Makita 5" stones.  They remove lots of material in a hurry, but wear quickly. Part #741407-8.  I have had trouble finding them so in a pinch I found that the black and decker stones from wal-mart are almost as good.  Steer clear of the Dewalt stones though.  They last forever, but accomplish very little. Attached Images
Reply:Say Boostin.... Next time the wire wheel gives up, and I imagine they do pretty frequently, go to the LWS and buy a good one.  I foget the name I use, but the knotted wire brushes last for many hours.  Cost about 4 times as much as the HF one, but worth it.Cheap cup brush has a tendancy to shoot wires into your arms, hands, face, legs, chest, the dogFlexovit Fast Cut wheels are about the best out there too.  Not terribly expensive.You can ruin any wheel by leaning into it.  It glazes the wheel, and it cuts like crap after that.  You have to lean harder to make it work.  It's like a dog chasing it's tail.Let the grinder and wheel do the work.  I know it seems slow sometimes, but just think how slow it would if you had to use a hand file.  It's all relative"Any day above ground is a good day"http://www.farmersamm.com/
Reply:That's actually a Toolshop twisted wire cup brush from Menards.  $5.83?  have had as good of luck with these as I have with the expensive ones.  I wear the wires right down to the cup then throw on a new one.  One cup lasts most of the day doing nothing but cleaning off rust.  They only seem to spit wire when I use them on corners or edges, and that is from the wires breaking rather than comming loose from the cup.  The one in the pic has about an hour of leaning on it and still looks same as it did in the package.
Reply:I got a DeWalt 5" with 13 amp motor and trigger switch that I like very much.  It was a little over $100 at Lowe's if I remember correctly.   I posted a write-up about it here on the forum awhile ago.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:I usually use a Milwaukee 4 1/2" grinder, I believe it's the 12 amp model. We go through alot of these at work. Most of the time it's due to operator error, meaning that the operator will feel the grinder starting to overheat and then smell the grinder overheating and see the bearing grease start to liquify and leak out of the grinder but still keep using it. Then they complain that they are junk. Usually when I use them I try not to put too much pressure on them, if you're pushing down so hard that the grinder is trying to stop it's probably too hard. To date I've only burned up one grinder and it wasn't in to good a shape when I got it. Also, I've noticed that using cutting discs will overheat a grinder quicker than a grinding of flapper disc.