The Forestry Forum

General Forestry => Chainsaws => Topic started by: trapper on April 15, 2019, 02:51:47 PM

Title: file
Post by: trapper on April 15, 2019, 02:51:47 PM
anyone use a different diameter file as the chain wears down?
Title: Re: file
Post by: lxskllr on April 15, 2019, 03:02:22 PM
I've thought about asking myself. I feel like I should, but don't feel like adding more gear to take care of.
Title: Re: file
Post by: John Mc on April 15, 2019, 08:05:31 PM
I've heard of a few people who switch from a 7/32" down to a 13/64" file on 3/8" pitch chain as the chain gets filed way back. I guess I can understand some of the rationale behind that, but I'm not sure I could tell the difference in my cutting. (I've used a 13/64" to sharpen

We also had someone on here a while back who was trying to convince folks to use a 5/32" file on their regular 3/8" chain (not on 3/8" low profile). This was all the time, not just when it was filed back. I'm not sure I could buy that one. If it really was a superior method to sharpen with such a significantly different sized file, I have to believe at least one of the chain manufacturers would have figured that out by now.
Title: Re: file
Post by: lxskllr on April 15, 2019, 08:22:02 PM
Quote from: John Mc on April 15, 2019, 08:05:31 PM
I've heard of a few people who switch from a 7/32" down to a 13/64" file on 3/8" pitch chain as the chain gets filed way back. I guess I can understand some of the rationale behind that, but I'm not sure I could tell the difference in my cutting. (I've used a 13/64" to sharpen

We also had someone on here a while back who was trying to convince folks to use a 5/32" file on their regular 3/8" chain (not on 3/8" low profile). This was all the time, not just when it was filed back. I'm not sure I could buy that one. If it really was a superior method to sharpen with such a significantly different sized file, I have to believe at least one of the chain manufacturers would have figured that out by now.
I'd go smaller than 13/64, but I'm not sure what size. I'd have to experiment. 13/64 is where I start. Same with lopro, which is where I really notice how big 5/32 is. Once the chain gets to a certain point, I can't get a good corner on the chain anymore.
Or I could just not worry about it. It all still cuts, and after a certain point, they get retired to beater duty anyway. I've got big files for big chains, and little files for little chains. Adding medium and extra small files isn't an attractive option. Just something else to organize in the system. Maybe I'll pick up a couple single files next order to see if the results are amazing. I suspect they won't be though, at least not for me.
Title: Re: file
Post by: John Mc on April 15, 2019, 08:32:24 PM
Quote from: lxskllr on April 15, 2019, 08:22:02 PM
Quote from: John Mc on April 15, 2019, 08:05:31 PM
I've heard of a few people who switch from a 7/32" down to a 13/64" file on 3/8" pitch chain as the chain gets filed way back. I guess I can understand some of the rationale behind that, but I'm not sure I could tell the difference in my cutting. (I've used a 13/64" to sharpen

We also had someone on here a while back who was trying to convince folks to use a 5/32" file on their regular 3/8" chain (not on 3/8" low profile). This was all the time, not just when it was filed back. I'm not sure I could buy that one. If it really was a superior method to sharpen with such a significantly different sized file, I have to believe at least one of the chain manufacturers would have figured that out by now.
I'd go smaller than 13/64, but I'm not sure what size. I'd have to experiment. 13/64 is where I start. Same with lopro, which is where I really notice how big 5/32 is. Once the chain gets to a certain point, I can't get a good corner on the chain anymore.
Or I could just not worry about it. It all still cuts, and after a certain point, they get retired to beater duty anyway. I've got big files for big chains, and little files for little chains. Adding medium and extra small files isn't an attractive option. Just something else to organize in the system. Maybe I'll pick up a couple single files next order to see if the results are amazing. I suspect they won't be though, at least not for me.
If you are starting with a 13/64" file on your 3/8 chain, I'm guessing you are using Stihl chain (they recommend a 13/64" file). If you want to try something smaller, the next common file size down from 13/64" (1/64" smaller) would be 3/16". It's the size commonly used on .325 pitch chain.

However, I've found the difference between using a progressive style depth gauge tool vs a "constant height" tool makes more of a difference in how a chain cuts when it's been filed way back than making small changes in file diameter.
Title: Re: file
Post by: Old Greenhorn on April 15, 2019, 09:26:28 PM
This is a complicated question and I would lean away from changing file sizes. However, you may find something like this that works for you or you like, so do what you want. 
 I look at this from a cutter grinders point of view: The tooth is designed to hold to same form for it's working life. Changing the file size will change the form. There are a lot of important features in the tooth design, not the least of which is the angle created where the file meets the top plate. A smaller file will create a sharper angle either leading to faster dulling, too much grab, or a more friable edge. More importantly the centerline of the file will drop with a smaller diameter and although it is rarely discussed, the location of that centerline is important to the edge shape. A smaller file will also likely cause the gullet to build up as you file further back. This just means you have to go in and clean out the bottom of the gullet every few sharpenings. Most folks never do this. I am terrible about keeping up with this. It can take longer than sharpening the chain. 
 Years ago I would use a 3/16 rat tail file (tapered) because I could reshape a whacked tooth into a sharp shape pretty quickly, or so I thought. After I got some education I realized that the proper tooth form was all over the map. Now I square file my chains after the first dulling and this works great for me and is fast (after the first time to change the tooth form and clear all the gullets, that can take almost and hour), but that gullet issue is even more of a problem with square filing. You have to clear out the gullets regularly with a round file to allow for the clearing of full sized chips. Chain teeth are complicated little buggers.
Title: Re: file
Post by: Old Greenhorn on April 15, 2019, 09:39:36 PM



If you can't get a good corner, I am thinking you have a thick gullet that needs to be cleared out. There is a really good thread here that everyone dealing with these issues and trying to understand sharpening should read. These guys express it better than I could. Gullet thread link. (http://forestryforum.com/board/index.php?topic=10005.0)
Title: Re: file
Post by: lxskllr on April 15, 2019, 10:06:17 PM
The gullet's the problem. Once the chain gets to a certain point the file doesn't fit under the tooth anymore, and every stroke on the side plate removes the top plate also. I notice it more on lopro chain, but that's what I use the most of. I've only worn out one 3/8 chain so far. I have it hanging on a stick out back. I should look at it to refresh my memory. I don't remember having quite the same file issues, but I was starting with a slightly smaller file in the first place. I'm not so sure Stihl chain /really/ takes a smaller file when new. You have to be especially careful to keep from making a beak. I suspect they consider 13/64 the best size for the full life of the chain, and extra care at the start is the trade off for a better end experience.
Title: Re: file
Post by: HolmenTree on April 20, 2019, 11:46:20 AM
I ended up with alot of older Oregon 5mm files which is the diameter between a 3/16" and 13/64". Perfect for my 3/8 chain use when filed   back to the half way point.
But I do like to start out from new with a larger 7/32" file to match the new chains today ground with their big aggressive side plate angles.

My opinion Stihl went to the smaller 13/64" file to make filing their harder heavier cutters easier to file. ;)