New chain after 2 cuts
My sharpened chain after 2 cuts.
They actually acted about the same during the cut
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My sharpened chain after 2 cuts.
They actually acted about the same during the cut
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I've been running them in my oak like that the past few weeks. They're set just a bit shorter than than what the depth gages is
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Agree 100%, I've been taking 2 with me, and just got the new one in on the last trip there. As I said earlier it acted about like my sharpened chains.
This log is taking me way longer thank originally suspected. I've got 3-4 more cuts still to go on it.
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Both chains need more "hook"
New chain needs the gullet cleaning out & the depth gauges lowered slightly.
Sharpened chain needs the depth gauges lowered less & rounded off properly. It also doesn't look sharp but that may just be the focus.
Bob's pic's from earlier show the kind of hook you want in order to get a bit of self feeding going on
New chain needs the gullet cleaning out & the depth gauges lowered slightly.
Sharpened chain needs the depth gauges lowered less & rounded off properly. It also doesn't look sharp but that may just be the focus.
Bob's pic's from earlier show the kind of hook you want in order to get a bit of self feeding going on
JD is on the money the cutters definitely need more hook.
The flat top rakers will also add more friction - they need to be rounded - look at the ones below.
The top one from Will Malloff's chainsaw lumber making book, the one under that is mine..
In the photo below of your cutter the angle shown in red is the raker angle and it's about 7.9º.
Stock chain is about 5.8º which I reckon is too shallow for most of your timber.
I never worry about raker depth or even cutter length and stopped using death gauges since 2007.
In Aussie hardwoods I use a raker angle of 6.5º and everything else comes out in the wash and chains last until the cutters start falling off from being so small.
Your raker angle is right up there but should still work for narrowish cuts in your timber.
Note - it's not the slope on the top of the raker but the angle between the cutter edge the wood and the point where the raker touches wood..
If that raker had a curved top was curved and the hook was right that chain should cut like a hot knife thru butter.
Depending on how wide your log is, once the raker is rounded this will increase the raker angle to the point where it may even be too much and teh cutters will just grab.
Then, to lower the angle you will have to take (lots of) swipes of your cutter but only do this if the cutters grab so's it starts to stall the saw
So,
1) add significant more hook,
2) round of the raker top, and (mat need to take some swipes of the cutter too)
3) clean out the gullets, to improved sawdust flow.
The factors to balance up are
Cutter Hook
Raker angle
Wood hardness
Wood width
Saw power
Drive sprocket pin count.
.
The flat top rakers will also add more friction - they need to be rounded - look at the ones below.
The top one from Will Malloff's chainsaw lumber making book, the one under that is mine..
In the photo below of your cutter the angle shown in red is the raker angle and it's about 7.9º.
Stock chain is about 5.8º which I reckon is too shallow for most of your timber.
I never worry about raker depth or even cutter length and stopped using death gauges since 2007.
In Aussie hardwoods I use a raker angle of 6.5º and everything else comes out in the wash and chains last until the cutters start falling off from being so small.
Your raker angle is right up there but should still work for narrowish cuts in your timber.
Note - it's not the slope on the top of the raker but the angle between the cutter edge the wood and the point where the raker touches wood..
If that raker had a curved top was curved and the hook was right that chain should cut like a hot knife thru butter.
Depending on how wide your log is, once the raker is rounded this will increase the raker angle to the point where it may even be too much and teh cutters will just grab.
Then, to lower the angle you will have to take (lots of) swipes of your cutter but only do this if the cutters grab so's it starts to stall the saw
So,
1) add significant more hook,
2) round of the raker top, and (mat need to take some swipes of the cutter too)
3) clean out the gullets, to improved sawdust flow.
The factors to balance up are
Cutter Hook
Raker angle
Wood hardness
Wood width
Saw power
Drive sprocket pin count.
.
To add to Bob's and others' posts.
I found the Woodland Pro (ground Carlton chain) ripping chain to have a crappy profile.
You need to first remove the bump caused by the grinder and open up the face of the cutter. The chain, stock profile, removes a very small amount of material per pass in a log, even with the depths lowered prior to the first sharpening.
My RA isn't perfect with this chain, but it's good for being early in the tooth-life
Photos here: https://www.arboristsite.com/threads/a-well-sharpened-chain.357484/post-7668749
Ignore the sap/pitch on the chain.
I found the Woodland Pro (ground Carlton chain) ripping chain to have a crappy profile.
You need to first remove the bump caused by the grinder and open up the face of the cutter. The chain, stock profile, removes a very small amount of material per pass in a log, even with the depths lowered prior to the first sharpening.
My RA isn't perfect with this chain, but it's good for being early in the tooth-life
Photos here: https://www.arboristsite.com/threads/a-well-sharpened-chain.357484/post-7668749
Ignore the sap/pitch on the chain.
Thanks for sll the input guys! I will get a bigger gullet on my cutters and hit the back of the rakers again before I get back out.
If I am thinking right, to get the deeper gullet, rotating the grinder head more should help with that correct?
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If I am thinking right, to get the deeper gullet, rotating the grinder head more should help with that correct?
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It's probably just as quick & easy to clean out the gullet with a hand file. You can do it with me your grinder by dropping the wheel into the front end of the gullet & (with the clamp loose) slowly wind the backstop in so it pushes the Chian along the wheel until it meets the cutter.
Adjusting your top plate cutting angle from the standard 60° to closer to 50° will give you more hook. I wouldn't file your chain with the low rakers at less than 55° until their heights/angles are sorted out or that chain will become extremely grabby.
Your pic from another post has the settings for grinding ripping chains in it (highlighted above).
If you choose to set the tilt angle remember it has to be tilted the other way when you sharpen the cutters on the other side
Adjusting your top plate cutting angle from the standard 60° to closer to 50° will give you more hook. I wouldn't file your chain with the low rakers at less than 55° until their heights/angles are sorted out or that chain will become extremely grabby.
Your pic from another post has the settings for grinding ripping chains in it (highlighted above).
If you choose to set the tilt angle remember it has to be tilted the other way when you sharpen the cutters on the other side
The gullet doesn't need to be deeper but its better if its smooth ie no bumps.
Yes sir, that's the settings I have been using.
I've been thinking about this and I started out the grinder with the 1/8" wheel. I dropped it and broke it so had to up to the 3/16" wheel. That could have caused less cut in the gullet.
Which is why I'm thinking, turn the head tilt to 65* instead of 60*. That should let the blade cut a bit deeper in the gullet.
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Definitely to low. mho OT
Fatherwheels
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Yep, thats going to cause the teeth to tilt down and drag an hop along the wood, will dig in a bit but not enough.
The 3/16" wheel is what you should be using on your 3/8" pitch chain.
You need the tilt set around 50°-55° to get the right top plate cutting angle (hook) for milling.
If you properly file/grind your chain regularly and consistently the gullet will be even but not as deep as is ideal.
Cleaning out the gullet is a separate step & the way you file or use the grinder is different & not part of normal cutter sharpening.
A larger gullet just aids chip clearance... your issues are with filing/grinding angles & depth gauges.
There was a member (MntGun) back in 2009-10 who used rakers even lower than those shown by the OPs. From memory he was using an 066 and was milling ~20" softwood logs at elevation at Snake River in Idaho. He was/is a serious CSM operator and cut enough wood to make a great looking barn. The OPs rakers have a raker angle of 7.9º while MtnGun used raker angles up to 9.5º, which for a new chain (0.25" gullet) corresponds to a raker depth of 0.042"
These extreme raker depths are easily accommodated and will produce the fastest cutting speeds provided;
- the saw has enough grunt
- the wood is soft
- the cut is not too wide
- 7 toothed drive sprocket is used
- cutters are sharp, well formed and have enough hook
On my 441 with a 25" bar and Lopro chain I use raker angles of 7.5º (that's 0.033" raker depth on new chain) and an 8pin drive sprocket in very hard woods - much harder than anything that northern hemisphere people would come across.
On my 880 and 076 with the 42 and 60" bars, 7 pin drive sprocket I use 6.5º (equivalent to 0.028" raker depths on a new chain. When I cut <30" wood I will sometimes replace the 7 pin with an 8 pin to perk things up a bit. It's far easier to swap sprockets than keep track of chains with different raker depths.
As usual when using much lower rakers there are trade offs.
- more vibe
- more wear and tear so aux oiling becomes even more important.
- possibly, poorer finish and greater chances of washboarding
- increased chances of kickback (not that relevant when milling)
What is not always recognised is as the chain wears (cutter lengths become shorter) the raker depths have to drop even further to maintain the constant raker angle. Some of my older chains have gullets that are ~0.45" wide and this means to maintain say the 6.5º raker angle the raker depth has to be 0.051" On my Loprochains I eventually start to run out of raker and saw dust clearance can become compromised especially in softer woods. This is how chains can retain their new cutting performance, right till cutters start dropping off.
Resharpened and went back out yesterday. Only have a picture of the new resharpened chain. Again it only made one cut and I had to swap back to my old sharpened chain, which made 3 good cuts and I quit for the day. I only llike 2 more cuts to finish this log.
In my cases I'm having better luck with the "extreme RA"
This cottonwood is alot softer than what I've been milling. Could that lead to why I'm having troubles with it?
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In my cases I'm having better luck with the "extreme RA"
This cottonwood is alot softer than what I've been milling. Could that lead to why I'm having troubles with it?
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Can you please explain how/why you are using such exact angles when describing raker angle? 5.8, 7.9, etc.JD is on the money the cutters definitely need more hook.
The flat top rakers will also add more friction - they need to be rounded - look at the ones below.
The top one from Will Malloff's chainsaw lumber making book, the one under that is mine..
In the photo below of your cutter the angle shown in red is the raker angle and it's about 7.9º.
Stock chain is about 5.8º which I reckon is too shallow for most of your timber.
I never worry about raker depth or even cutter length and stopped using death gauges since 2007.
In Aussie hardwoods I use a raker angle of 6.5º and everything else comes out in the wash and chains last until the cutters start falling off from being so small.
Your raker angle is right up there but should still work for narrowish cuts in your timber.
Note - it's not the slope on the top of the raker but the angle between the cutter edge the wood and the point where the raker touches wood..
View attachment 965946
If that raker had a curved top was curved and the hook was right that chain should cut like a hot knife thru butter.
Depending on how wide your log is, once the raker is rounded this will increase the raker angle to the point where it may even be too much and teh cutters will just grab.
Then, to lower the angle you will have to take (lots of) swipes of your cutter but only do this if the cutters grab so's it starts to stall the saw
So,
1) add significant more hook,
2) round of the raker top, and (mat need to take some swipes of the cutter too)
3) clean out the gullets, to improved sawdust flow.
The factors to balance up are
Cutter Hook
Raker angle
Wood hardness
Wood width
Saw power
Drive sprocket pin count.
.
Thank you
Sure,
5.8º is the resultant angle on a new 3/8 chain, gullet is nominally 0.25" and raker depth is 1/10th of that 0.025
This works out to inverted tangent (ATAN) of (0.025/0.25) = 5.7º
This is a safe, low wear. moderately efficient, raker angle.
However in terms of actual cutting efficiency it's on the wussy side.
If you have the grunt then increasing this angle by 1-2 degrees cuts way more wood.
This is an old video but it shows how I do it with a Digital angle finder (DAF).
Start by zeroing the DAF on the bar rails and then place the DAF on top of cutter and rock it down onto the raker - making sure the DAF does not touch elsewhere. measure angle and swipe away till it reaches the desired angle.
Yes it takes a lot of patience - but look at how short those cutters are - that chain still cuts like a new one.
Music selection is entirely coincidental!
Im not stressed to get the exact same angle on every cutter/raker.
If I'm after 6.5º I file the raker till the angle is over 6.5º but even if it's 7 or even 7.2º I don't stress about it. If I stuff it up and go to far, then I swipe the cutters a few times but I don't really care if the cutters are not the exact same length. I haven't bothered to measure cutter lengths since about 2008. If cutter looks a bit long I usually give it a couple of extra swipes when sharpening .The extent to which the cutter grabs wood is a combo of the cutter hook, raker angle and cutter length. Long cutters will also wear more in the next cut than shorter ones so will show uo as having more glint on their edge at the next touch up. This means more metal is removed to get rid of the glint eventually shortening them back to the same length as teh others.
In practice I don't measure the angle on every cutter every time I touch the rakers. I check the raker angles at home after every few hours of actual cutting but in the field I take care of rakers by giving them 2-3 swipes every 3-4 times I touch the cutters which in my hard woods is for every saw tank of mix.
Here is your cutter - I had to rotate the image to get the bottom of the cutter horizontal otherwise this generates an incorrect measurement.
The red lines define a raker angle of about 3.5º - this is about 60% of the stock raker angle which explains slow cutting and why the cutter does not grab the wood.
I reckon you could also use a touch more hook.
I agree with Bob re "a touch more hook"... As he has also pointed out, that cutter isn't on the level (so to speak).
When sharpening on the grinder I make sure I push the cutter both back onto the stop & down so it sits flush before tightening the clamp. This ensures that I'm actually grinding the angle the machine is set to.
When sharpening on the grinder I make sure I push the cutter both back onto the stop & down so it sits flush before tightening the clamp. This ensures that I'm actually grinding the angle the machine is set to.
I do the same when sharpening. I'd actually forgot the pic and just set it back in the grinder to take it.
Yes, I see there now as why that chain isn't doing as good as my other. I will work on getting the angle on down before I get back out.
I did get this big cottonwood finished up yesterday so back to my dried oak for a change!
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