First Grind
Actually took it for a 'spin' today. I have a loop of STIHL 3/8 low profile chain with several heavily damaged cutters that I am going to spin out, so I thought that these would be good to experiment/play with. This chain would normally be sharpened with a 1/8 inch wheel. See Post #182 in this thread:
http://www.arboristsite.com/community/threads/philberts-chain-salvage-challenge.245369/page-10
I clamped the grinder to a bench, and worked like I would with a full sized grinder: multiple light 'taps', grinding with the profiled edge of the wheel; dressing the wheel with a stone, etc. I tried just 'kissing' the edges for a touch up; hogging off damaged cutters; cleaning up gullets; and lowering the depth gauges.
- The grinder needs to be positioned much higher. I could not easily see the wheel touching the cutter. Looks like its back to the step ladder!
- It takes little time to get used to the same hand controlling the vise/brake handle, and the tapping/grinding. So a little coordination is required! The other hand has to hold the chain in position until the vise locks. As with any vise, the user has to be sure that the cutter is properly seated before grinding in order to get even grinds.
- This is a light duty device. It will not hold up, or give acceptable results with excessive pressure, or ham fisted operation (as 67L36Driver notes). Definitely not a commercial or heavy use tool.
- The 'mods' I made, cleaning up the vise, etc., helped with smooth operation. The reinforced brake cable (Post # 84) hit the center post when rotating the vise from R to L, but that is a minor issue.
- It is possible to 'burn' a cutter with this device (I tried, intentionally!). Good grinder technique is still needed.
- There was a lot of variation between R and L cutters in cutter length and depth of grind. Each side needs to be set up independently.
- I was able to clean out gullets OK, by backing off the positioning dog and lowering the grinder head a little.
- Grinding depth gauges was a challenge. *Note that the ramped depth gauges on this chain are not very common. But the grinder head is fixed at 60°. And the brake lever style clamping vise makes it difficult to 'slide' the depth gauges under the wheel, as was demonstrated in one of the videos, using the other style vise. When I tried to turn the chain around to grind the L side depth gauges facing the other direction, the vise clamp would only grab the depth gauge in front of the cutter, so the cutter and depth gauge rocked and moved too much.
- The knobs to advance the chain are of little use. It is easier to grasp the chain and pull it forward or back.
- I was absolutely able to clean up some really rocked cutters and to make acceptable cutting edges on this chain.
First Use Impressions
* I think that someone who knows what a sharp cutter is supposed to look like, has a light hand, and is willing to make a few tweaks to this grinder, should be able to sharpen smaller pitch chains with it. *
Someone expecting miracles, automatic operation, or heavy duty use, will be very disappointed.
It is not a true competitor to the larger, more expensive grinders, but if this is what I had, I could work with it.
I have ordered some 3/16 grinding wheels to try with larger pitch chains.
I am confident that taping '
Silvey' to the top and side of the grinder improved sharpening performance significantly.
I really want to try the other style vise (these '
cheap' grinders are starting to cost me a significant amount of money!)
Philbert