I realised over the years that on a 14 inch blade only the firts 2 inches are made of decent abrasive...
Is that because there are more fibre the closer you get to the arbor or because no matter the constant rpm of the saw a 10 inch blades has much less inch per minute of abrasive working on the surface... 14 x 3.1416 x rpm = ipm when it's reduced by 40% and fibers are added...
Over the years we tried so many brands even the walter representative made me try his whole assortment with limited failure or success. Add to that that some (most) cheaper blades are of poor quality and reinforcment inside is not always center and never cut straight, i have a home made saw driven by a 5 hp motor wich work best with mid priced blades (1/4 x 6 flat and straight when blade is worn less than 10 inches, or 3/8 x 2 1/12 flat cold rolled 4 stacked).
Performnce wise, not bad! but the dust.... I plan to go dry cut but fear the noise...
Results 11 to 14 of 14
01-28-2013, 06:12 AM #11Senior Member
- Join Date
- Mar 2011
- st-eustache qc.canada
01-30-2013, 12:54 AM #12
Here's the physics:
The cheapo wheels use abrasive grit that melts VERY NEAR the melting temperature of the target metal (steel, usually), or grit with impurites that melt BELOW steel's temp. So when the kerf gets hot, the cheap grit liquefies instead of the metal, but the grit sticks to the wheel (UNlike the steel flakes, which oxidize & shrink rapidly as they go around the backside of the wheel & flake off), so you make no progress. If you have a diamond truing tool for your bench grinder, you can use that (or maybe a common quartz stone) to break the glazed grit & expose more fresh abrasive, but the only real fix is to buy high-quality name-brand wheels.Walk softly & carry a BIG SIX ! ! !
MM211 + SM100
01-30-2013, 12:12 PM #13Senior Member
- Join Date
- Sep 2009
Let the wheel cool
I find that the best way to prevent the problem you describe is to not let the wheel get too hot. If I have a big cut, I will pull down for a few seconds, let up a few seconds, pull down a few seconds, etc. Ever since I started doing it that way, I no longer have the problem you describe.
I will say that 1 inch square is about my limit for the abrasive wheel. If I have to cut 1/2 inch by 1 inch, I put it on edge, go up and down until I get through it. They work a lot better for 1/4 inch thick material, but always put the material on edge. I think that I could probably cut 2 inch by 1 inch material by putting it on edge, and just taking my time.
I use my abrasive wheel a fair amount, so I have some experience.
My two cents.
01-31-2013, 12:05 PM #14Member
- Join Date
- Nov 2010
Thanks for all the responses....some good advice
The "blade" that mad me write this thread is Pferd. made for steel.
I have been using this cutter about 20 years. I have already been using many of the methods described here. One I have not tried is setting the materiel on end.
I have about 200 (see them on craigslist all the time, I usually pay less than a dollar each) of these abrasive cutoff wheels of various brands. Some deteriorate faster than others but they all seem to "clog" about the same.
I agree that is it is a noisy messy not precession cutting device, but for cheep cutting it is the way to go.
I also have a Milwaukee 14" dry cut........really NICE cuts, I have cut a 9lb 5" channel where drop could only be measured with a micrometer, but the blades are EXPENSIVE!
I would list all my tools but you guys would just cry.
Thanks for all the replies!