Allowable tooth length differential

rasawing · January 16, 2023, 04:27:40 PM

A rule we have all heard is to (when sharpening your chainsaw chain) make sure the teeth wind up being the same length (and therefore height). But what kind of tolerance is there for that? In other words (and I am just making up numbers here) if one tooth is 6 mm long, the next is 7, then 6, then 8, then 6 again, etc, etc......is that kind of variation ok?

I've never heard a number on this....but I'd like one. A lot of people just go by how it cuts....but getting it right before then would be great. Thanks.

barbender · January 16, 2023, 04:33:06 PM

On my bars out to 24", I don't think it matters that much. I'm not taking a new chain back to 2mm, just because I hit a rock and banged up 4 teeth. They can vary some, it's more an issue that the teeth don't vary a lot from one side to the other.

blackhawk · January 16, 2023, 04:44:47 PM

When I use my Oregon grinder, I try to keep the length of my right and left teeth within .010" (.25mm) of one another. I've probably had them vary by as much as .015" and I couldn't tell a difference. That's the worst that I have let them get so the real tolerance could be even more.

doc henderson · January 16, 2023, 05:17:28 PM

I think you are talking about performance. a longer tooth is also taller. so a few teeth that are ground back due to damage, will not be doing as much cutting. If all on one side it may curve in the cut. I save the crappy worn out chains for when I am doing something I know may damage a chain. I have a bunch that hang on a nail and tend to use the ones with 3 or 4 sharpening's on them. remember to just bump and touch the sharp edge of the tooth several times if using a grinder, and do not full on grind till the metal is blue.

ButchC · January 17, 2023, 08:50:14 AM

Obviously the very best performance will come from exactly equal size cutters and depth guages. However in all my years of handle time Ive never been able to discern a 100% chain from a 95% one out in the field cutting. I have run chains that didnt need anything but an eyeball to see that the cutters were not all the same length and I'll be hanged if I could tell them from a new one as long as they were sharp. While Im not advocating sloppy sharpening. I think waaaay too much has been made over tooth lengths on cyber saw forums. I guess what I am saying is eye ball your cutters, if one side or one cutter appears short or long then very the file strokes to suit, other than that concentrate on angles, proper file technique, and timely touch ups rather than tooth length science and you will see more benefit out in the field than measuring teeth with a micrometer.

Al_Smith · January 17, 2023, 10:34:55 AM

In a perfect world it would be best if all cutters were the same length .We don't live in a perfect world though .Cutters get broken,bent and missing .It will still cut but not as fast or smoothly .If it gets on your nerves hang it on a nail and use it as a root cutter .

Real1shepherd · January 17, 2023, 11:09:39 AM

Progressive raker gauge and you're done with the bother. Lots of vids out there on it, including a good one with Buckin' Billy. There's a lot about Buckin' I don't agree with....not a fanboy, but the dude knows how to sharpen a chain.

Kevin

C4treefarmer · January 17, 2023, 01:13:41 PM

The idea of filing each tooth the same is to prevent it from cutting "crooked". The problem is the logic behind it isn't addressing the real issue of raker height. Use a raker gauge and forget about the tooth size.

There is a channel on YouTube called "buckinbillyraysmith" he explains saw sharpening perfectly and to a science, if there is one!