grinder wattage

Higher wattage/amperage equates to more power. A 4-1/2" doesn't need more than 6-8 amps where a 5" model ought to have 10 or so and the 7-9" models usually have 13-15 amps. I have a 4", 5" and 7". I wish I had gotten a 4-1/2" instead of the 4" but I got a good deal and went withg the smaller unit. I have decided that the 5" is a good all-around size for ME. Mine has the long handle rather than the barrel type.

It really depends on what your intended application for the grinder will be. Let me tell you, if you are doing lighter work such as touching up the occassional ugly bead, grinding off a little rust so as to get clean metal to weld, or similar, get a 4 1/2 inch grinder. You will get tired of wrestling a 15 A, 10 lb., monster grinder for small stuff. However, if you are using your grinder to V-groove a lot of 1/4" plate to weld, you (and your grinder) will be much happier if you have a beefier unit.
I cannot speak for Milwaukee grinders (great drills though). I would recommend Porter Cable or Flex (some PC models are made by Flex) and Metabo as quality brands that I have used. In a recent thread, Ernie also recommended Fien, Trumpf and Hitachi though I haven't used those. Others may recommend the cheap Harbor Freight units that run US$15-20. Personally, I don't buy cheap tools. For limited use I'm sure they'll do just fine though.
Remember that one sure way to kill a little grinder is to bog it down trying to do too much with it. If your rpm slows way down and the grinder seems to be struggling, that is a good sign that you either need to back off a little or get a more powerful model.
Cheers,
Jeff Dantzler

I've had so many MadeInChina moments that I've sworn off cheap junk forever.
I will gladly spend 10 times more on a quality tool than some piece of junk which will need to be replaced and may be dangerous.
If my only option is an import from certain locations, I will not make a purchase. I'll sooner make my own tool from scratch no matter how long it takes.
I've got a Milwaukee drill that I've been abusing for over 20 years and it's got just as much power it had the day I bought it, I'm convinced that it will outlast me on this Earth no matter how I try to kill it.
I've used other people's drills which wont even drive a 3 inch drywall screw through a 2X4. Very sad to see low quality, low power being rewarded with U$Dollars.

I have a buddy in the tool distribution business. You would be surprised to know just how many big name power tools and their parts are made in China in the same factories as the generics. Nowdays, "Made in U.S.A." doesn't mean it is so. At least for now, the Chinese do not make decent hand tools that I know of.
Coop
"

Sam, Grinder wattage for me equates to longer life, cooler running and faster work. Someone once told me that when buying any hand power tool, I needed to buy the one with the most amps available because somewhere along the way, I was going to need them. I had a B&D for ten years because at the time I bought it, it was about as good as I could get. Replaced it with a Milwaukee. There were a couple with equal or nearly so amps, but I wanted the grip or paddle style switch. Don't like the slide switches so many use now. Makita had one that I considered but had the wrong switch. Makita has about as heavy duty tools as any but I do not like the strain relief systems they use. Something about the material makes it crack off just behind the housing. Good luck!
Jerry
Sam wrote:

Guess this is just the same as with HD motorcycles, which use many parts made in Taiwan, and other far eastern countrys!
Jonno
to know just how many big name power tools and Nowdays, "Made in U.S.A." doesn't mean it is so. > At least for now, the Chinese do not make decent hand tools that I know of. > > Coop > > "

As an example, the Dewalt dry cut saw that I bought a year or so ago had a little "made in china" sticker on it. I was stunned after paying almost $400 for it. However, it is a well built tool and I would not want to be without it. Notably, the two blades that came with it are made in UK.
I think that the specifications and quality control are more important than the country of origin. These days China is capable of making a decent product, such as my saw. The saw works great and appears well-made--no doubt part of it's price went to pay for higher manufacturing standards and quality control. Harbor Freight cheapies are spec'd & made to be _cheap_ and you get what you pay for (bushings instead of bearings, plastic instead of metal, etc.) I can't comment on their QC.
It is getting increasingly difficult in our ever-globalising world to buy American. Especially as another poster mentioned since many multicomponent items are a conglomerate of international parts. I have taken to settling for quality. I used to (and still do) seek quality by sticking with US, German/Euro, Canadian, etc. That expanded to include Japanese, Taiwanese, and now with my saw, even Chinsese stuff. The trick is finding stuff that is of good design and durable construction. Every country has companies making garbage, but now even China can turn out decent goods as long as the parent company (such as Dewalt) has a good design and holds the production facility to high standards. I imagine Dewalt decided that the Chinese factory could not produce a blade to their liking and thus went with UK (= more $) fabrication for the blades.
But I digress...
Jeff Dantzler

As another example of that, GM has built the most advanced engine plant in the world in China. 2004 and later GM cars and light trucks will come with engines made in this plant. Modern machinery (China is the world's largest importer of advanced manufacturing machinery) and good management define quality. Costs are mainly defined by labor costs and tax/regulatory issues.
China is now getting the best in terms of machinery and management while still retaining the lowest costs in terms of labor and tax/regulation. It is an unbeatable recipe for manufacturing dominance. It is how the US became the dominant manufacturing power, and why the rust belt lost that position due to old plant, ever rising labor costs, and excessive taxation and regulation.
The same cycle of rise and fall is likely to happen in China over the course of the next century (we're already seeing the fall strike Japan, Germany, Taiwan, etc who started up the modernization ramp 50 years ago). But for now, China is on the rising crest of the cycle, and they are making the most of it.
Gary

On Sun, 31 Aug 2003 13:32:09 +0000 (UTC) in sci.engr.joining.welding, "Jonno" uttered this remark:
Don't tell a HD owner that!
Dan E-mail: snipped-for-privacy@ri1.arg (ROT13 encoded)

I bought an old, big (3/4" chuck, 10 amp) Milwaukee drill (model 1805) at an auction last week for $60. Seems to work fine. I was going to sell it on eBay and try to make a few bucks, but after reading the last few posts it sounds like I should keep it.
Dave Wilson

I bought an old, big (3/4" chuck, 10 amp) Milwaukee drill (model 1805) at an auction last week for $60. Seems to work fine. I was going to sell it on eBay and try to make a few bucks, but after reading the last few posts it sounds like I should keep it.
Dave Wilson

I've never noticed a perceptible difference between power ratings. OTOH, I use UK 240V power, which gives better performance for lightweight hand tools than US 110V (or UK on-site 110V).
The basics:
Get a 4 1/2" grinder, not a 9".
Buy some anti-vibration gloves too. My grinders also have neoprene handle grips added (strips of stick-on pipe lagging foam).
Get a grinder with a spindle lock button (only needs one wrench), but don't get one where this lock is easily knocked by accident.
A quick release nut is useful (it has a flip-up handle built in), but you can buy these separately.
Don't forget those gloves.
Now the optional stuff:
To be honest, there's little to choose between 4 1/2" grinders, other than their reliability and service life. Look for epoxy-coated windings. Look for air-cooling that's adequate, but not excessive. A cheap way to make a powerful grinder is to over-cool an under-sized winding - naturally this isn't conducive to a good lifetime.
Switch quality is variable. Avoid those where the switch jams on when full of dust (AEG, some cheapies). Go for one where the lock-on is easy to engage and disengage, even with gloves.
I hardly use disks these days - flap wheels every time. Get some good ones, like the coated Hermes one - they're worth the extra money, especially on clog-prone materials, like thick paint. Keep loads of disks on hand, so you always have the right type and grit.
Weight isn't a big factor on a 4 1/2" grinder, but it certainly is on a 9". Look at the weight of the cheap Chinese ones - it's nearly double that of my (also Chinese) Makita. Ergonomics in general is a much bigger issue on a 9" grinder.
Grinding speed is limited by the linear speed of the wheel. This is the same for large and small grinders, so 9" grinders have to turn at half the speed of 4 1/2" grinders. Quite simply, a 4 1/2" grinder cuts just as much metal as a 9", yet weighs half the amount !
OK, so this is a simplification. But it's not a bad one - don't get a big grinder until you already have a small one, and even then it's a lot less useful than you'd think. A big grinder can cut near its limit without slowing down (the bigger motor) and it gives a deeper cut with a cut-off disk (mainly useful for stonework). It may also have less tendency to cut divots, because of the greater radius. But don't expect it to rip through metal at three times the speed of your small grinder.
A 9" grinder is also a sizeable gyroscope and hard to control. I mainly use mine with a 7" flap wheel in it, partly because I can't get 9" flap wheels, but mainly because it's more controllable with a smaller disk.

More likely, some idiot who can't trim postings will fail to read the following paragraph. Don't be so literal-minded and quick to post an argument, just because it's on Usenet.
Here's the bit you didn't read:
So you're letting untrained people (because no one gets through any real training without handling both) wander round your sites ?
Now my apologies to Sam the original poster if I'm making an assumption here, but I suspect that he's not a professional or full-time welder and is a bit new to the world of choice out there. Now I'd just hate to see him go and spend twice as much of his own money, to get a bigger machine and find that it was actually _less_ useful to him and certainly didn't cut at an appreciably faster rate.
You don't need a 9" grinder. If you're one of the people who does need a 9" grinder, then you'd already know this, so ignore the first sentence.
Now maybe this is a local effect, but I have a much wider range of abrasives available to me in 4 1/2" than I do in 9". I'm a big fan of using the best abrasives I can find, because IMHE they cut better and last longer, dollar for dollar. I can't do this on the 9".
Except that 4 1/2" grinders run at 12,000 rpm and 9" grinders run at 6,000. The linear speeds are the _same_, and a 7" disk is at a disadvantage.
Another issue is that of grind quality. If there's a slight imbalance in the wheel, then a big grinder hits the workpiece with it at half the rate. Look at the quality of finish you get afterwards - the 9" always has a rougher finish.
Is anyone saying otherwise ?

That's not very nice, I made no personal attack on you. Ease up a little, try to enjoy life.
Don't be so literal-minded and quick to post an Oh but I did read it.
The only untrained people wandering around are project managers, surerintendants, purchasing guys, office geeks out for a stroll : ). When your job site is a street corner, where a gas line is being lowered or hot tapped, or a new line is making a road crossing, or your right of way is going down a residential street, then you will have a lot of onlookers. We certainly do, some are curious, some worked on a pipeline as a kid back in Oklahoma, some just want to know what's going on, some have never seen a pipeline in their life, but want to come out and tell you how to make that hot tie in, 'cause they know all about weldin stuff. It sometimes makes for an interesting day. And, you get to hear most every old wives tale ever told about welding. Including yours.
regards, JTMcC.

You already are buying Chinese products. They're so pervasive now that unless you're the archetypal Montana shack-dwelling Unabomber, then you're alreadyusing a lot of products made there, even without realising it.
Some Chinese products are great. My bike frame is Chinese-welded titanium - beautiful piece of work. My 9" grinder (another thread) is made in PRC, despite being a "Japanese" Makita (I almost bought a Hitachi made in Ireland, which is even stranger). If they want to, then the Chinese are capable of making fine products as good as anyone else's. Just look at their track record in space launchers.
But at the low end, there's just no competition for them (a little from Indonesia, or Eastern Europe). It's not that all Chinese products are cheap crap, but that all cheap crap is now Chinese. We are all _out_ of the cheap gimmick market, either Europe or America.
That's as much to do with the wax formulation. Those sintered candles are often mainly stearin, which is cheaper but less luminous.

snip thats what happened to my old grinder!after cutting into some stone the switch began to jam on the locked position. i tried cleaning it with some WD 40 but only got a marginal improvement. anyone manage to clean theirs? with compressed air or by opening it up?
b.t.w. it has a variable speed knob. what would you need to vary a grinders speed for?
thanks, Sam

It means someone stamped it with CE (the font is distinctive too - the outer edges of the letters almost make a circle). This mark has been mandatory on almost everything in Europe for a few years now (there are religious loons complaining about "mark of the beast" again), meaning that it complies with the relevant European standards.
The mark applies to anything electrical, hot, moving, toys, or protective against the first three (there are actually 23 groups)
However it's a vague scheme, and it's pretty much self-certification by the manufacturers. It's no real guarantee of anything. To quote from the electrical regs:
"(a) The Low Voltage Directive is not designed to impose safety standards. Its primary purpose is to ensure free trade through the removal of technical barriers.
(b) Conformity with standards is not compulsory, but it can be used as one means to demonstrate compliance with the safety principles enshrined in the directive. "

"John T. McCracken" wrote in news:_325b.8$ snipped-for-privacy@news02.roc.ny:
Sure, but them mosquitos are a different thing.
LOL! Yeah it's one of them "LOW TECH" electrodes nobody uses anymore(that's intelligent anyway) BUT for that "rusty metal", that 6010 gets the ole job done. Anyone can run that 6010/6011 and see right off, it's a terrible rod next to dim' dere' 6013/7014 rods. Why they always leave a pretty bead. Them rods are some proffessional stick electrodes, you have to be pretty damb good to run dim der rods. The welds look all shinney' and all, "hey honey look what I done, don't that look pretty". Now with them der 7018 and 6010 rods you can't get nottin' done, and they sure don't look pretty. I wonderin' why? I think I'll buy one of them better weldin' machines. I'm goin' to try to get me one of them "inverters", I hear they last a good long time, and I'll be buildin'up them edges on them turbine blades in no time. I don't like them "innershield" wires either, all but that 211-MP, now that some good wire, it looks really pretty too. Hell, that NR-232 sure sucks. I'll have to go down and bring ole JTMcC, a six pack of beer, no maybe I should bring em a case, them dumb welders, when you get them intoxicated, hell they'll do about anything for ya.(free that is) Oh, here comes ole JTMcC now in his weldin' truck, damb it's near 11:00 PM, ah it's just a small 5 minute job, he won't mind, he'll weld up this ole axle for me, after all I've bought him CASE of beer.
LOL!
Kruppt

Here in Thailand I have had a Makita circular saw, excellent quality, but manufactured in China at a Makita factory. Too bad some loser stole it last month. That was a great saw. Also had (also stolen) a Black and Decker hammer drill, made in England. That was good, held up well to some serious abuse. Also have had good luck with South Korean stuff, have an LG angle grinder that is very solid. Heavy duty, and cost about thirty bucks. I like the Korean tools for value and quality, especially LG. Also with some Taiwan power tools, a name Talon is available here. Not bad, good cutoff saw and sander I have. Have a Chinese drill press that works great, at least I think it is Chinese. "Tiger" is the only name on it, no location. Very impressed for 75 US dollars. Have a local Thai arc welder, great value and welds great. 500 amp, one hundred dollars. Makita makes a another cheaper label called Maktec, nice angle discs and drills, but don't know if it that name is available in the States.. There are other Chinese brands, "Clinton" I think is one, I once spent eight dollars on a Clinton angle disk grinder, but it got too hot to hold without gloves, then the switch melted. You get what you pay for. And I was actually dissapointed with the Bosch saw I bought here, the bearings didn't hold. Anyway, over here in SE Asia there are a bewildering number of names and brands, some great and some not so great in terms of value for money.