Chains won't cut anymore

[BrewBoy]

OK, to dispel any rumors that I'm grinding it at 0 degrees or that I'm running it backwards, here's a side by side comparison with a single link of new chain. The left cutter is the new one.

However, looking again at the second picture makes me think I'm still cutting it too low.

 

[Philbert]

Your 'after' chains look much better (good photos by the way - sometimes hard to get good close ups).

The proof will be in how they cut. Let us know.

Philbert

 

[buzz sawyer]

Is the tip rounded over on the right? Also, any chance the chain was overheated from grinding and now won't hold an edge?

 

[BrewBoy]

It's not rounded on the right leading edge. As for being over heated, I can't say for sure. It doesn't really cut correctly, right after I sharpen. I get disgusted quickly and grab a much smaller Echo saw that cuts like a champ and has been sharpened on the same grinder (different wheel).

 

[Philbert]

BrewBoy,

Take a look at your last photo, and notice the edge on the sharpened cutter (right) and the new cutter (left). See the white line (reflecting light) on the right cutter? This suggests that the edge is not as sharp as on the new cutter (no line or 'glint' visible).

You can try to see what you need to do with your grinder to get this type of edge. Maybe your last pass could be 'feather light'. If it is still not working, you could try getting the edges as close as you can with your grinder, then 'finish them up' with a file.

P.S. if your cutters were overheated, you would see color changes ('bluing')on the cutters themselves. Very easy to see.

Philbert

 

[BrewBoy]

Yeah, I see what you mean, I might need to touch up with the file. Thanks for pointing that out.

 

[trimmmed]

Is the tip rounded over on the right?

It's not rounded on the right leading edge. As for being over heated, I can't say for sure. It doesn't really cut correctly, right after I sharpen. I get disgusted quickly and grab a much smaller Echo saw that cuts like a champ and has been sharpened on the same grinder (different wheel).

That point definitely is rounded down. That little chamfer puts the point lower than the top edge. you need to file or grind that back until the edge on that top plate is a straight line right to the point.

 

[CTYank]

After reading the links/suggestions here and looking at my chains, I'm starting to think my problem is that I'm grinding it too deep in an effort to remove the gullet at the same time. Here are some pictures:

The first three are before I resharpened it at a shallower depth. Even though the saw had only been used a little after this sharpening, I can see that the point was never sharp or dulled quickly. ...

Let me know what you think and thanks again for all of the help.

In the first three pix, the cutters are extremely dull. Butter knives.
In the latter, they're looking so-so.
In all, the depth gauges (rakers) look to be about .080" below the teeth- waaaaaaaay too much.
In all, it looks like much of the body of the cutters has been overheated.

If you're spitting dust, stop and file the cutters. You'll save engine, bar, chain and operator torture. And time. Grinders remove much more metal than files do.

 

[atvguns]

Is the tip rounded over on the right? Also, any chance the chain was overheated from grinding and now won't hold an edge?

seems to me that after grinding my chains hold an edge better I thought the heat was hardening them a little

 

[WidowMaker]

neigther of those look very sharp to me, and what is all over those chains??????

 

[BrewBoy]

I think it just oil and some sap. The chain likely got a little hot from me trying to force it to cut.

 

[jrclen]

BrewBoy,

Take a look at your last photo, and notice the edge on the sharpened cutter (right) and the new cutter (left). See the white line (reflecting light) on the right cutter? This suggests that the edge is not as sharp as on the new cutter (no line or 'glint' visible).

I'm a newby too, here to learn. But could this be caused by the grinding wheel having a worn in ridge which is grinding that bevel on the top of the cutter? That might explain the change from when it worked fine. Maybe dress the wheel?

 

[Philbert]

I'm a newby too, here to learn. But could this be caused by the grinding wheel having a worn in ridge which is grinding that bevel on the top of the cutter? That might explain the change from when it worked fine. Maybe dress the wheel?

Simple answer - No. If your wheel had a worn in ridge, you would have an uneven edge, like a serrated knife or saw teeth. It looks like the wheel is not touching that part of the edge.

That said, dressing your wheel is the right thing to do in order to keep the half round profile on the edge - this gives you the properly shaped hook, gullet, and side plate grind.

Read through the manual that came with your grinder, or download the Oregon one from their website.

Philbert

 

[jrclen]

OK. Thanks Philbert.

 

[Philbert]

Read through the manual that came with your grinder, or download the Oregon one from their website.

That sounded a little funny or terse when I re-read it. Don't mean it to sound as if I was blowing you off, and hope you did not read it that way. It was meant as a suggestion that there would be more information in your manual that you would find useful if you are trying to understand more.

Philbert.

 

[jrclen]

No problem Philbert. I didn't take it the wrong way. I was just wondering what could cause that symptom.

 

[Naked Arborist]

just read this thread wow lol

Strange shape on the back side of those cutter teeth.

My grinder needs to be nudged just a bit toward the cutter tooth after it enters the cut or it just pushes away from the tooth and causes the rounded edge on the top of the cutter teeth. It's got some slop in the arm so it wants to ride around the top cutter when it goes down. Leaves a nice sharp edge on the side and a ####ty rounded one on the top.

Heat of any kind will defiantly harden those teeth. I sent one chain (first and last) to the shop and it came back blue toothed and killed a brand new file after ten teeth and it seemed really hard to file. I smoked a few myself when I bought a old used grinder the next week to do it right myself. I was going into the grind way too fast. I could not sharpen the blued ones in the field with a file.

I should know this after building enough rear ends in cars and trucks. If you ever get one all worn down on the pinion teeth check the hardness rating on the pinion shaft and you will find that it was not 3 or 4 points harder than the ring gear. Bad move on the manufactures part there :eek2: . So heat hardens steel, no dought. Harder steel chews up softer stuff every time. That's why they make carbide steel cutters.

If your ripping with this chain down the end grain of the wood it will kill a cutter fast at 30 degrees angle.

The chain may also be getting some millings thrown at it from the links, they are softer than the bar and being forced into the wood will chew the bottom of the chain down quick. It will chew the chain down and run the millings right back up through the cutter teeth. I can clearly see that the chain is worn down on the rail side of the links. Add some oil to them and you have the perfect environment for milling or honing down the cutting edge on the top of the teeth. High speed, friction and hard steel is not a good mix.

I have also noticed the chrome plating on the cutter teeth is chipped. I did that way back when and found out it was caused by the little bits of steel chipping off the edges of the bar where it needs to be dressed as mentioned by some in this thread.

Add all that up and it seems to be a recipe for a quickly dulled chain IMO. Just my 2.5 cents here so, take it for what is worth otstir: or not.

Good Luck

 

[BrewBoy]

Better late than never

I had a surplus of firewood cut, so I really haven't used this saw since posting. However, I got it ready this past weekend and went after a dry red oak tree with about an 18" trunk. It cut perfectly and I am now sure that the problem was the "flair" on the bar. Someone suggested that I look at this and file it off, which I did, and that solved the problem. It was very subtle, but just enough to grab in the kerf and make it difficult to cut.

Thanks to everyone for their help. Besides learning about bar flair, I learned a lot of additional info about chains.

 

[B Harrison]

Is the tip rounded over on the right? Also, any chance the chain was overheated from grinding and now won't hold an edge?

I think a few things

Your getting your tooth hot and its loosing the edge quickly.
Your angles aren't that great for crosscuts,
What kind of chain is it, because your "new link" just looks odd. I think my new chains are shiny and smooth on the top plate, polished even looking.

After you grind try putting 2 good passes with a file on each tooth. Roll the file a little away from the cutting edge and tap it out after every few teeth.

Hope you have this cleared up soon.

 

[514mach1]

I use a belt sander to take off that burr, and then put the bar on edge, perpendicular, to the belt to "true" up the rails. Just gotta be careful to not catch the nose sprocket when sanding the rails at 90*. And I agree, the bottoms of the chain links (where it contacts the bar) look like they're getting beat up a bit by a worn drive sprocket (rim).