Last Thursday I ordered the Timberline Sharpener from timberlinesharpener.com. I was surprised to find it was delivered two days later on Saturday morning, excellent service. I also purchased an extra burr, a 5/32" for my climbing saws. Over the weekend I sharpened five saws. Here are my impressions:
First, I have been sharpening with an electric grinder for about fifteen years. For quite a few of them I would do 15 - 20 saws on Sunday nights to get them ready for a week's work with a tree crew. It has always bothered me that no matter how I tried, I could never get them to cut as well as a new loop and that the edges did not last as long as when they were new. Currently I use an Oregon 511 to repair damaged cutters and file with a little Husqvarna file guide in between grindings to keep them sharp. The guide is the type that drops over the top of the chain, the file running on plastic rollers and lets the operator turn the file. This keeps a saw productive but does not throw chips with the raucus abandon of a new loop... So I tried the Timberline.
The first attempt was a Husky 575, 20", full comp. I'd watched the vid and had read the instructions and the first attempt was a clumsy one but I soon got the hang of it. Tighten the two outside screws enough so the sharpener won't move. Snug the center screw up enough so that the burr will go into the cutter easily. Use multiple passes, very lightly on the first and second passes. My first saw took about an hour, fumbling around, trying to find the best work methods but the results were really fine. I have a fresh pile of big balsam poplar in the yard. The chain threw nice, fat, rectangular chips, no masa harina (corn meal.) Next was a 84cc Dolmar, also 20" bar and full comp. It was easier. Best advise I can give is don't hurry. Make multiple light cuts. When I was finished, I cut another poplar cookie. It seemed to cut better than new chain. After that I switched to two climbing saws, Echo 360T's with 12" bars and lo-pro chain. They seemed to me to cut better than they ever had, like they had found an extra 5cc's. The last saw was a Husky 394 with a 28"bar that i use for flushing stumps and dicing cottonwoods, our biggest trees here in N. New Mexico. The full skip chain had some light damage from its last job but three passes later the cutters looked like new and threw chips four feet behind me.
To summarize: The Timberline puts a precise razor-sharp edge on the chain and does it without overheating the steel and annealing it. So the edge should last as log as one on a new loop. I'd recommend using a grinder for serious damage, if you hit a rock or nail, then follow with the Timberline to restore the cutters. I've had guys tell me that they could file a new chain and make it cut better. Now I believe it. Also, I was surprised by how much abrasive residue from the grinder appeared as I was sharpening with the Timberline That's another reason chains don't stay sharp after grinding.
My opinion: This is a good tool.