Well, the engine wasn't bogging down at all and I didn't have to "cam" the bar into the tree to get it to cut fast either. About a 12" dia fir and I was able to hold the saw slightly back off the spikes and with just modest downward pressure cut through the whole thing in seconds. The stream of elongated chips coming off was semi spectacular. Obviously the target being freshly dropped fir helps a bit.
Pete C.
That number is the pitch, or spacing between rivets. Measure across _three_ rivets, and divide by two. There's a second number that goes along with the pitch: gauge. It's how wide the drive links are where they fit the bar groove. Usually one size of pitch has a corresponding gauge and no others, but you can get chains of thicker or thinner gauges in the same pitch. .050" is typical for homeowner saws, IIRC. Changing pitch means changing sprockets, and changing gauge means changing bars. Keep that in mind when you shop. You also have different cutter arrangements. Standard has a cutter, spacer, cutter, spacer around the full length of the chain. Semi-skip will have one spacer, then two spacers, then one again, with cutters in between. Skip has two spacers between each cutter. Standard is more aggressive, full skip is best for really long bars that will need the most room for chips and you can drive a longer chain with the same powerhead without bogging down. Semi-skip is pretty common as a compromise. "Safety chain" or low-kickback has the exact same sizing system. The obvious physical difference is that the spacer links have a hump on 'em. That hump causes pretty lousy cutting performance after you sharpen the chain a few times. The cutters themselves are available in various profiles. The oldest is square ground chisel, which is extremely aggressive. It's also fickle about sharpening and will go dull in an instant. The new rounded and semi-chisel profiles are easier to sharpen, hold and edge longer, and take less horsepower to run. Just have to cut a bit slower. For fast cutting with a little saw, but reasonable maintenance, .050 gauge, whatever pitch as long as it matches your sprocket, standard or semi-skip, non low-kickback chain. (assuming you're able to locate some in that size) If you can choose between 7 or 8 tooth sprocket, get 7. It lets a little engine keep its revs up. There are two varieties of sprockets out there. One that looks like a spur and is called a spur drive, the other looks like a washer with slots around the edges, called a rim drive sprocket. The second type is removable from the clutch bell, so it's cheaper if you plan to keep the saw long enough to wear out a few chains and a sprocket or more. Also marginally more tolerant of a stretched chain. Or do it the easy way and just go by trade name. Oregon micro chisel ripping chain is probably what you'd want. I don't have a cross-ref to tell you the equivalents from other manufacturers. Sorry. Disclaimer: The above is based on lots of maintenance experience and medium-low actual chain sawing experience. Could be biased somewhat.
Let the record show that Gunner Asch wrote back on Sat, 01 Oct 2005 13:59:57 GMT in rec.crafts.metalworking :
Use the bowsaw, slice the trunk or branch at close intervals, make lots of little (or not so little) roundtuits.
tschus pyotr
I heard of a pastor who carried a fish weight around, to hand to people who would try and beg off saying "Well, I'd consider it if I felt lead...".
PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.