why double rakers?

[RI Chevy]

Different chain cutters.


Good reference for different cutter styles.

https://www.oregonproducts.com/en/findingtherightsawchainforyou

 

[sonoransaw]

Thanks! Yeah, I would say it was definitely a full chisel....I'm just wondering how long those wicked points are gonna last with these desert hardwoods we cut. I've been supplying him with most of his firewood, so he hasn't had to cut much with it yet....

 

[RI Chevy]

Just keep your semi chisel chain nice and sharp! You'll be all set...
Take a lesson from guys down under. They run .325 chain in that HARD wood they have.

 

[Philbert]

Philbert, I refuse to extend them the dignity of their proper moniker....they do not improve the quality of anyone's life imho....

Low kickback bumpers were originally designed to make the chains cut smoother, especially with smaller diameter limbs; the reduced kickback performance has been described as an unexpected benefit. Either way, it is like calling a 'mouse' a 'squirrel': people will be confused and look at you funny.

'Dual depth gauges' (28)

'Low kickback bumpers' (42)

" The depth gauge is thus positioned to engage the bottom of the saw kerf to thereby control the depth of the cut made by the cutter element and prevent undue digging of the cutter element into the material being cut. Such depth gauge has a leading edge which tends to have hooking engagement with branches of the brush being cut. This results in jerky operation of the saw chain and, in extreme instances, in stalling of the chain Saw motor or breakage of the saw chain. In accordance with the present invention, a connecting link adjacent the forward end of each cutter link is provided with a guard portion shaped to prevent such hooking engagement by the associated cutter link. The guard portion may either sufficiently fill the spaces between the cutter links to prevent branches of the brush from dropping into such spaces or may be shaped to provide a portion which lift branches of the brush being cut out of Such spaces. in either case, such branches clear the leading edges of the cutter links to prevent the hooking engagement above described. The spaces between the cutter links are, however, not completely filled so that space is provided for carrying chips or sawdust out of a kerf when the chain is employed for cutting branches of considerable size." Raymond Carlton May 8, 1959

Ray was a talented engineer who split off from Oregon Chain / Omark Industries in 1963 to form his namesake company, and is credited for promoting 'progressive' filing and many chain design and manufacturing improvements. Ray died in 1997 and his company was purchased by Blount, Inc.; the parent company of Oregon in 2008.

Philbert

 

[AVB]

Personally for plunge cuts here using 3/8lp, I like the ramped bumpers as they got very kickback when tip plunging so I can drv wedges in for splitting wood that wedges simply will just bounce back out if I didn't do the plunge cuts.

 

[sonoransaw]

You win, Philbert, as I suspect you always do.... Great back story on both the chain and its inventor... Thanks for posting that.

Thanks, AVB...can't argue with experience...

 

[Wilhelm]

IMHO low kickback chain does not necessarily cut slower or worse than its non-low kickback counterpart.
For example, I do not feel any difference between Oregon LGX and LPX filed the same way and I like my chains to take a good bite.

As @RI Chevy noted, the difference in performance You are experiencing is due to the different tooth geometry, taking Your low kickback loop is semi chisel.
I don't like semi chisel much, it is slow and wastes power - it has its place though.

The backed on stuff is not bar oil, it is tree sap - I get a lot of it on my chains when bucking turkey oak.
There is no point in trying to clean that stuff off, it'll just bake on again.