Raker profile

[Carhartt]

What raker profile works best? Flat top with a rolled over leading edge or a raker ground on say a 55 degree angle with a lower front and higher towards the tooth. Does one way or the other throw the tooth off when in the cut?

 

[mitchm1]

I set them at 5 degrees for some saws
But firewood cutting I go to 15degrees


Sent from my iPhone using Tapatalk

 

[Firewood Bandit]

Rounded like OEM ones are. Use a diamond dresser on the wheel to get the correct shape.

 

[Lightning Performance]

Slight top angle. The entry needs rounded or beveled.

 

[Wonkydonkey]

I think the raker shape plays a big part in the way the toof cuts, ie if you look at stock photos of chains, you will notice the different shape rakers.
It is said that the raker digs into the wood while it’s being pulled along. So a flatter topped raker will dig into the wood less.

I would guess a full chisel chain, with it’s faster cutting would have a more pointy raker than a semi chisel chain.

Don’t get me wrong, I don’t think it’s clear cut as I say, as with all cutting of wood, there are many types and dry as a bone to sopping wet and frozen.
So what works for somebody may not work for others...

Take a look at this manual of types of chain cutters (lots of pics) you may see the slight difference or bigger differences
https://www.chainsawbars.co.uk/wp-content/uploads/chain-info.pdf

 

[Carhartt]

Rounded like OEM ones are. Use a diamond dresser on the wheel to get the correct shape.

What dresser are you using? I have a Stihl dressing block and not that accurate. As Wonky shown in the pdf, not all rakers are close to the same.

 

[Philbert]

Rounded profile. You don't know exactly what part will make contact, and you don't want a sharp point that will dig in, or act like a leverage point (making it act like a taller depth gauge).

JMHO

Philbert

 

[Carhartt]

By the way can someone explain to me the logic in those rolled over rakers that look like a mini cutting tooth? I have never found a good way to grind them.

 

[Wilhelm]

You mean the Oregon Vanguard / Dolmar 496 chains?

I love them, have a few, all were gifted to me - thank You guys Sondre @SOS Ridgerider & Wayne @Dub11 .

They are easy to grind IMHO, small bench grinder works best.
Modifying the raker


Reshaping the raker


Cutting off the raker's bent over part will lower the raker making the loop a little more aggressive, this normalize's through a couple sharpening cycles.

 

[Philbert]

By the way can someone explain to me the logic in those rolled over rakers that look like a mini cutting tooth? I have never found a good way to grind them.

They are a reduced kickback design. You are supposed to file the flat area only, along the OEM angles. More info in the Oregon Maintenance and Safety Manual.

Philbert

 

[Carhartt]

That's the raker I was talking about.

 

[Philbert]

That's the raker I was talking about.

A lot of guys get confused by this unique design. Several guys have posted in these threads that they like the chain, once they figure out how to adjust it.

Philbert

 

[Wilhelm]

I have modified a few and converted them to the HLSupply Archer FastFiler sharpening jig (5.5mm file) - they cut great and hold a good edge in skidded beech and oak logs.

I like 'em!

 

[Firewood Bandit]

What dresser are you using? I have a Stihl dressing block and not that accurate. As Wonky shown in the pdf, not all rakers are close to the same.

Sorry didn't see this sooner.

I have several different styles, for making a concave profile for rakers a single point works great.

https://www.mscdirect.com/product/details/03502044

For profiling the wheel for cuttes I'd use a flatter one.

https://www.mscdirect.com/product/details/50670561

 

[Wood Doctor]

Last year I gave up on this idea that I "invented" five years ago and it was a mistake to give up on it:

It works. Forgive the crude drawing. Most rakers have a curved top, so this method will not change that curvature. But, when you instead flatten the raker triangle straight down, it changes the profile completely.

 

[Carhartt]

Is there any downside to moving the raker forward like your picture shows. I mean farther from the cutting tooth.

 

[Philbert]

Last year I gave up on this idea that I "invented" five years ago

I remember that post!

Won't you end up with 'needle' rakers / depth gauges? Dig in instead of gliding over the wood?

Philbert

 

[Lightning Performance]

Is there any downside to moving the raker forward like your picture shows. I mean farther from the cutting tooth.

Actually this should be an advantage. The drag is getting farther away from the tooth. This leaves more room for chip on full comp. It does require more to be removed off the top because your moving farther away from the cutter tooth and decreasing the angle of attack. Six degrees or more is the happy place for good bite imo.

Going to try this tonight on a chain. I'm really targeting the hook on my tooth for milling. Two chains with different drags will be a good test. I'll try to keep the six degree lead in angle consistent and see how much of a drag height difference between the two grinds. They may perform different or not.

 

[Wood Doctor]

Is there any downside to moving the raker forward like your picture shows. I mean farther from the cutting tooth.

Not that I have noticed. The idea is to hold onto most of the curvature on the back side of the raker (not shown in the crude drawing). Most of the cross sectional shape is maintained.

 

[Marshy]

Last year I gave up on this idea that I "invented" five years ago and it was a mistake to give up on it:
View attachment 191837
It works. Forgive the crude drawing. Most rakers have a curved top, so this method will not change that curvature. But, when you instead flatten the raker triangle straight down, it changes the profile completely.

I've had similar thoughts to this, same basic concept. I've thought about filling the back side of the raker with my flat file. I gave up on trying it because there is a good amount of material that needs to be removed until you're into the ramp of the raker and can start marking it shorter.