Open discussion on hook angle for CSM chain

Okay guys, been doing some searching and this is a topic that gets mentioned on occasion, but never really gets fully addressed. I'm gearing up for a big milling season and am going to get my chains fully tuned.

I'm going to BobL's raker advice, thinking this is one place I'm having some major problems due to the advancing age of some of my chains. However, Northern has their grinder back on sale for $100, and I'm wondering if it's worth the the investment for messing with hook angles.

The floor is now open.

oldsaw said:

Okay guys, been doing some searching and this is a topic that gets mentioned on occasion, but never really gets fully addressed. I'm gearing up for a big milling season and am going to get my chains fully tuned.

I'm going to BobL's raker advice, thinking this is one place I'm having some major problems due to the advancing age of some of my chains. However, Northern has their grinder back on sale for $100, and I'm wondering if it's worth the the investment for messing with hook angles.

The floor is now open.

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Do you mean using "progressive raker" depths or "cutter hook"?

BobL said:

Do you mean using "progressive raker" depths or "cutter hook"?

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Cutter hook, I understand the raker issue and am adopting it, great work, btw, even though you have been preaching it for some time. I've had the saws parked for way too long. This is one aspect of sharpening I've never messed with.

oldsaw said:

Cutter hook, I understand the raker issue and am adopting it, great work, btw, even though you have been preaching it for some time. I've had the saws parked for way too long. This is one aspect of sharpening I've never messed with.

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I haven't messed as much with hook as I have with rakers because I
reckon as long as the saw is self feeding on a slight slope and doesn't go blunt too quickly then I don't worry about it too much.

For a number of years I used a 13/64" file on a 5/32" file guide in the belief that it reduced the hook but after thinking about it during the year I realized this setup increased the hook. I'm moving to a 13/64" file on a 3/16" guide to see if this improves cutter edge life.

I have adopted the sharpening method that I read in the book "Chainsaw Lumbermaking" with very favorable results. I bought one of the Chinese made northern tool grinders which has served me well for this purpose.

I start with a new loop of Carlton full comp/full chisel chain and use these angles:

Top plate: 0 degrees/hook angle: 50 degrees from vertical =slowest feed rate but smoothest finish.

Top plate 10 or 15 degrees/hook angle: 50 degrees from vertical= faster feed rate but a little rougher finish.


The later one with a 15 degree top plate is my standard grind anymore. It was noticeably faster than the woodland pro ripping chain that came with our 48" mill. I actually ground the ripping chain this way when I finally put it on the grinder. Now it will cruise through the wood too!

I primarily sharpen my chains on the grinder, then a couple of times in the field with the file, then back to the grinder to even everything up again and drop the raker depth accordingly.

IMHO there is nothing better than the quality of Carlton full chisel it will simply hold an edge longer than any other chain.(especially fresh off the grinder) And let me say i have tried them all on my carving saws over the years.

From Will's book:

Will Malloff said:

I grind my ripping chain cutters straight across the fronts at 50 degrees from vertical (40 degrees from horizontal)

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I barely started experimenting with the hook angle last fall and didn't get very far. Will try again this summer.

Lo-pro ground 40/10/10.

Got hook ? :msp_sneaky:


40 degrees was easier said than done. First off, the wheel guard was hitting the vise handle, so I had to completely remove the wheel guard.

Only about 1/2 of the cutter length is left on this chain, so there was plenty of room for the wheel to fit between the cutter and the raker -- but I doubt there would be enough room on a newer chain.

And yes, I did have to re-shape the bottom of the grinding wheel, as Malloff suggested.

Will try to speed test it later this week.

Time to speed test the Malloff grind. :msp_sneaky:

My usual 12 1/4" pine cant. A hot-rodded 066, 36" bar, injecta-sharp lo-pro chain ground 40/10/10 as shown in the previous post. 6 degree rakers.

1st test -- 1.26 inch/sec

2nd test -- 1.26 inch/sec

3rd test -- 1.20 inch/sec

Average -- 1.24 inch/sec :msp_thumbsup:

That's 30% faster than 60/10/10 lo-pro had done with the same saw in the same cant.

OK, so the Malloff grind is faster. There's got to be a downside ?

-- it'll probably get dull faster, especially in hardwood.

-- it's harder to grind, prolly impossible to grind on brand new chain. With a new chain, you may have to start out at 60 degrees and then gradually change the hook angle a little each time you sharpen.

Malloff used a 0 degree top plate angle, not 10, so that's yet another experiment for me to tackle.

Found his book in the fall and tried 0 on the top cuts slick ,smooth ,sweet and doesn't seam to dull earley . but i was going the wrong way on the hook ,and hit a wall on horse power .My 88 got doggy slow so tore it apart was fine, put a 36 " bar on and it makes cookies quick . You can bet its gonna make a big differance dropping the hook to 40 degrees. Got to get a grinder , its time.

mtngun said:

There's got to be a downside ?

-- it'll probably get dull faster, especially in hardwood.

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Yep but as long as it make it thru one big cut in hardwood, chain's gonna be touched up anyway.

-- it's harder to grind, prolly impossible to grind on brand new chain. With a new chain, you may have to start out at 60 degrees and then gradually change the hook angle a little each time you sharpen.

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Or start with a file

Malloff used a 0 degree top plate angle, not 10, so that's yet another experiment for me to tackle

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My guess is that will slow it down - I'm thinking skew plane/chisel?

Another variation on the Malloff grind.

3/8 WP milling chain, 40 hook, 0 tilt, and 2 degree top plate. Used a 1/8" wheel rather than the usual 3/16" wheel. 6.1 degree raker angle.


Why 0 tilt ? Just an experiment. It's easier not to tilt, so if it cuts just as well, why not ?

Why 2 degree top plate ? BobL had mentioned somewhere that if you grind to 0 top plate, you run the risk of making it slightly negative, which would be a bad thing. So I set the grinder on 2 degrees to make sure any error would be on the positive side.

This chain will be tested on my rebuilt and mildly ported 084. I've got to make some new cants, so it probably won't get done until tomorrow.

mtngun said:

Another variation on the Malloff grind.

3/8 WP milling chain, 40 hook, 0 tilt, and 2 degree top plate. Used a 1/8" wheel rather than the usual 3/16" wheel. 6.1 degree raker angle.

Why 0 tilt ? Just an experiment. It's easier not to tilt, so if it cuts just as well, why not ?

Why 2 degree top plate ? BobL had mentioned somewhere that if you grind to 0 top plate, you run the risk of making it slightly negative, which would be a bad thing. So I set the grinder on 2 degrees to make sure any error would be on the positive side.

This chain will be tested on my rebuilt and mildly ported 084. I've got to make some new cants, so it probably won't get done until tomorrow.

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Mtngun,

Can you let us know how the finish turns out when you make your tests. I have been thinking if filing my chains with more hook, but was afraid I wouldn't get as smooth of a finish as I'm getting now. I'm filing my chains at 10* with very little hook.

jerry-

820wards said:

Can you let us know how the finish turns out when you make your tests. I have been thinking if filing my chains with more hook, but was afraid I wouldn't get as smooth of a finish as I'm getting now. I

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Haven't tested the 3/8 yet but have made several cuts with lo-pro at 40/10/10. Looks no better or worse than the finish from regular WP ripping chain.

Can somebody explain top plate angle and tilt angle. Thanks.

betterbuilt said:

Can somebody explain top plate angle and tilt angle. Thanks.

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Tilt is the tilt of the grinder vise, or if you are filing, if refers to whether you hold the file horizontal or 10 degrees from horizontal.

Top plate angle as shown in Malloff's drawing, except his drawing labels 0 degree top plate as 90 degree for some odd reason.

I'll have to give it a try on one of my chains.

Thanks
jerry-

Okay I'm following. I just wasn't sure if I knew where the numbers were coming from.

It does seem like it would dull easier. Interesting.



Thanks, Mtngun.

OK, 40/0/2 3/8 as described previously.

Mildly ported 084.

8 pin rim.

12 1/4" seasoned pine cant.

1st pass -- 0.75 inch/sec

2nd pass -- 0.86 inch/sec

3rd pass -- 0.86 inch/sec

average -- 0.82 inch sec.

This was the first time the 084 had cut wood, so I don't have a direct comparison. It bogged easily with the 8 pin, so I will retest with a 7 pin.

Finish was quite a bit rougher than my 066. Again, this was the first time the 084 had cut wood, so I don't have a direct comparison. Will retest with the standard WP grind.

Nice work mtngun.

Re: Washboard, It looks like you are getting chain speed and log width synchronicity. Try angling the mill relative to the log so that the synchronicity is disturbed.

Cheers

I like the cool texture, just the 7 pin might do it . It almost looks a bent {arrant } tooth . Bob they are just ripples in the chain caused by narrow lumber and empty chain at the right frequency .