[Sharpening/rakers] Can't keep-even, just bent a bar and saw was cutting 'sideways' when in-cut, any tips?

eyehearttrees

Active Member
Location
Tampa-Area
I've watched hours (cumulatively) of videos on sharpening, have probably gone through half a dozen files sharpening the many chains I have for 5 bars, always thought I was OK....then it happened.

Last week I was bucking-up a large Oak I'd felled and had just 'got the saw's chain ready' the night before. I found my saw wouldn't cut at a straight downwards angle, I'd hold the powerhead that way but it'd cut leftward as it went through the wood, if I tried to man-handle it to cut straight it'd even give sparks from pushing chain-into-bar too much. When done I found I'd actually bent the tip of the 18" bar.

The "got it ready" work the night prior was 2-fold, am still trying to figure-out which was a bigger culprit:

#1 - sharpened the hell out of the teeth, aiming for the most-aggressive (35deg) angle (I usually go 25 or 30deg, for cutter-sharpness-longevity), this was like the 10th sharpening for this chain I mean the teeth are getting quite small lol. I was very happy with the look of the chain, thought I did it well.

#2 - filed the rakers, was more aggressive than usual -- I expect this amplified uneven right//left cutter issue...

Made me wonder "If I brought rakers lower on my other chains, would they all cut this crooked too? Is my sharpening way off-point, and I'm only *not* seeing it because the rakers aren't allowing a large-enough variance?"

Any 'remedial' sharpening tutorials? Have seen all the common ways, just rewatched a few of Billy Ray's videos (oh that reminds me, do you guys all support ditching the file-guides?)

What about rakers? I can't figure it out but my guide for the raker-filing is faulty, it has never once allowed me to use it to sharpen a raker (even on my 18" where the teeth are almost done from too many sharpenings, according to my cheap raker-guide the rakers still didn't need to be taken-down, that's why I just took a hand file and 'free handed' it, was intentionally aggressive but think I brought them a good 50% lower than intended, unsure if that may've been a bigger contributor to crooked-cutting than the teeth IE crooked/irregular-heights on the rakers, they were definitely not homogeneous/consistent :/
 

JaredDTS

Member
Location
Kill Devil Hills
I like the combo sharpeners that do rakers and the teeth at once, every now and then if I'm in a hurry, but usually I like a file and file guide. I like not worrying about getting the depth correct and I dont see a benefit of going no file guide. Same for the rakers I use a stihl raker gauge or I just use the combo sharpener a few swipes after the regular file. Buckin does his own stuff, I just watched a video where he reccomended using larger file than is normally reccomended. It works for him and may be better but I haven't needed to worry about anything like that.
 

Reach

Well-Known Member
Location
Atglen, PA
So, a couple quick tips on sharpening and setting rakers. Make sure the teeth are the same size on both left and right sides, you might be able to do that by eye, or use a pair of calipers to confirm.

The very steep grind angle makes for a more aggressive cut and may contribute to the crooked cut, but probably is not the primary cause.

Buy a good quality raker gauge, if the one you are using now does not work, throw it away and buy one that works.

My recommendation to restore these chains is to find a saw shop/sharpening shop that has an automatic grinder, and let them grind the chains back to spec.
 

Jehinten

Well-Known Member
Location
Evansville
Did you inspect the chain after it failed? Worn that low, cutting with an aggressive angle and too low of rakers; its possible that you broke a few teeth off causing it to cut more aggressively on one side than the other.

I've had a few chains that I ran a little longer than I should have only to find several teeth completely gone when I did replace the chain.
 

Rob Stafari

Active Member
Location
Cincinnasti
With chain issues it is always best to post some pictures so we can get a better idea of what's going on. (from side and top far enough out that we can see a couple cutters in each photo) Could be the angle is off from side to side. Rakers not even from side to side. Have you ever dressed the bar? They can start causing similar issues when warn unevenly. The more warn down a chain gets, the lower the rakers need to be to take the same bite. Do a little googling on progressive raker gauges and progressive raker filing. Low rakers themselves won't cause the crooked cutting, they can just amplify whatever else may be causing the issue. Now uneven rakers is another story. Without being able to see the chains though, all this is just speculation as to the real issue at hand.
 

Barc Buster

Well-Known Member
As Rob said above a progressive raker guide is the way to go. 20201204_082016.jpg
It's going to allow you to keep the relationship between your depth gauges and teeth the same on a tooth by tooth basis. 9 times out of ten this will keep the chain cutting straight.
 

Frankie 1

New Member
Location
Buffalo
The raker height on a stock chain is around .026 ... By the time you are near the witness marks the depth gage MUST be increased to maintain the approx 6deg angle the chain has when new ; So you May need the rakers at around .040 or more to maintain this angle at this point .. The raker determines the depth of cut of each cutter- it simply won’t cut worth a darn if it’s not progressive! If you have a chain that has been sharpened many times and the cutter is down to a nub ... .026 will not be sufficient and saw will cut poorly if at all ... post a pic of the chips
 

swingdude

De' Island Buzzer
Location
Barbados
The amount of arbs that cannot sharpen chains properly is mind boggling. It is a skill set that needs to be mastered. Understanding the relationship between cutters and depth gauges is inperitive. Knowing how to clean out the gullet of the cutter to create a proper even kerf while cutting is key. Getting that gullet clean and uniform between cutters is a huge skill. Properly sharpened chain can improve your cutting vastly. That being said I only use a handfile for cutters and flat file for rakers or depth gauges. I will not even try to help you here as you seem to not grasp the basics. There are many vids on youtube that can teach the basics. Sounds like your bar rails are fucked though. Filing and counting passes is a great starter. Cutters do not have to be the same size but their depth gauge gaps should be otherwise chain will run rough. If gap is too aggressive on one side the curve will ensue.
 

Wrangler

Well-Known Member
Location
Woodbine
I agree with @swingdude , i think either your bar rails are spread from heat/wear or the underside of your chain that rides in your bar grove is worn to a taper, or both.
Either one of those conditions will cause your saw to curve as your cutting. If you’re bar rails are spread you can put them back to speck with a $35 tool called a rail closer and get a little more life out of it. If the bottom of your chain is spent get a new one. Either way even a beat bar and chain should fall/pull thru the wood for a couple inches until it starts to curve if you’re cutters are sharp.
 

evo

Well-Known Member
Location
My Island, WA
Practice, and reread your original post as the answer to your question is likely in the ramblings.
Sharpening free hand really isn’t that hard, even I can do it, along with the takers. I personally know my left hand stroke is stronger by about 1.5 time. So I just go gentile on that side.
Yes every once and a while I’m off, and will fuck up a filing.
If you’re forcing your lil 18” until you bend the bar to try to cut straight, perhaps there are bigger issues at play.
No shame in junking the chain if it’s filed close to the whiteness marks. I do from time to time, but one should be able to learn how to free hand well beyond the whiteness marks. For myself 8 times out of 10 I junk the chain when the cutters start breaking off and the file digs well into the links.
 

swingdude

De' Island Buzzer
Location
Barbados
I made 3 vids with a chain I had just sharpened....3.....then decided this is a right of passage. Dude needs to learn this on his own. He will be so chuffed when he gets it. Maybe a tad poorer but will survive.
 

Wrangler

Well-Known Member
Location
Woodbine
Just a couple tips to save you some time and aggravation
1) not all files are created equal.... buy some Stihl files to get started,that way you’ll have a benchmark for how a quality file should cut
2) get a good vice and stablize saw bar in it with chain tight
3)do every other cutter then turn saw around and repeat
4) if chain has been super heated from being sharpened with some sort of electric or air grinder it can change temper
of cutter steel making it hard to sharpen with file( cutting nasty stumps can also have that effect on chain)
 

Bart_

Active Member
Location
GTA
I never really thought about the progressive raker depth and 6 degrees before. Thanks. I have noticed the Stihl raker depth tool doesn't agree with brand new chain. The new chain is deeper.
 

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