In most instances unless your doing production work the cheap stuff gets you by just fine. Lots of different choices when it comes to grinding wheels you should be safe grinding on the wheels that came with it for HSS, make sure you cool the tool often while grinding as well. A Arkansas stone or India stone is great to use for honing and polishing the HSS so that it is nice and sharp. With so many different cutter materials used these days I would always make sure the grinding wheel referenced the material if its not plain jane steel when matching the two.
I would think maybe a variable resister inline on the cord might do it. Most of the bench grinders that I use to sell would run about 1750rpm. Rarely sold 8" though as the Baldors were too much money in that size. Buffers were usually 3450rpm.
IIRC coupon expires on the 12th. you have to join the forum to access the coupon. I posted below with a internet price match and the coupon you can get the hf 9X20 lathe for $469. almost used the coupon on a 12x36,would have been $1400 + tax but no room in my garage.
$139.99. It was on sale for 199.99 and they didn't even blink about the coupon. In fact there were two old timers observing my purchase and they were real quick to inquire about the coupon. I had two more printed out in the car, so I gave the coupons to them. I think they would have taken me out for beers if they had the chance. Said they were there to buy a large Mill and Lathe.
Man, just got to love this forum. Thanks guys.
This message has been edited by ST42 on Mar 10, 2007 11:12 PM
That may well be the case,but when ever your working with power tools there is always going to be a chance for an accident. Considering that a bench grinder is probably the most used tool in a typical shop that isn't many accidents at all compaired to other power tools. From what I can see there it is far more likely you will get struck by lighting,but do you go through your entire life worrying about it? I won't even get into car accidents or just crossing the street. Have a good one Rich.
This message has been edited by chevell1322 on Mar 12, 2007 11:30 PM
I would invest in a new Green silicon carbide wheel for that new grinder. I have one on mine and while they do not last as long as the grey wheels they are much better for toolbit grinding. They are a tad softer so they are not as likely to get the bit too hot if you stay just a tad too long. It is also easier to get a smoother grind that needs less honing to get to the sharp stuff. You can get one of the diamond dressers but I just use one of the multi star wheel dressers and it is easy to get a true square wheel for proper grinding. Remember to always quench the bit every few seconds of grinding so you do not draw the temper on your toolbit. Good luck.....
Rich, I bought my wheels from Enco (see the links). I'm using the gray or white wheels for HSS tool grinding. The green wheels are primarily used for sharpening Carbide tools.
One thing you should do is check the wheels that came with your grinder BEFORE you use them. They may indicate maximum safe speed as the Enco wheels I have do. The important thing to do before installing them is to give them the ring test. If they have a ring to them when lightly tapped while being held loosely with a screw driver through the center hole they are fine. If they thud they may be cracked. Launching a grinding wheel at 3400 RPMs is exciting but you don't want to be in the flight path! I don't recall if the wheels that came with my cheap hardware store grinder were labeled. I didn't want to take a chance so I replaced them with the Enco wheels without using them. By the way, 3400 RPMs is a typical grinder speed. Just make sure the wheels are rated at least that high.
Your message about cooling and temper reminded me of the following.
At my factory there was a machine that was used to reduce thickness on a portion of strip metal. It used carbide cutters, and sometimes needed different relief angles. The operator of this machine brought me a cutter to touch up. It was just a quickie, so I didn't turn on the coolant on the surface grinder. I gave the tool back to him, and was told that the cutter was no good. He said that since I hadn't used coolant, I took the temper out of the CARBIDE.
(For those familiar with carbide, they're probably snickering about now.)
"Nuke 'em til they glow, then shoot 'em in the dark"
a drill bit always drilled a smaller hole that the bit. Bein' puzzled by the comment the question was asked "then how do you get the bit out of the plate??".
After a bit of snickerin' from those around he didn't seem to get the joke. I guess the engineer was thinking that the drill bits wear in diameter and get smaller. Since I ain't an engineer the holes I get are always a bit larger than the drill.....humm, maybe it's just them cheap drills I use. LOL
from what I understand the green silicon carbide wheels are primarily for grinding carbide cutters including brazed carbide on steel cutters but I have had good luck sharpening and profiling HSS cutters with the wheels as well and as I said before the finish quality is better and generally requires less hand honing. I am going to have to get the grit on my wheels for ya but I gotta help my mother move all her household goods into her new home this weekend. It was nice talking to you on the phone and I apologise for not having more time to chat but I had to get the damn U-haul back before they charged my mother another day of use.