I noticed you guys discussing raker depths and it sounds like you need to read the FOP progressive sticky.
To optimize cutting, the raker depth needs to change as the cutter wears. Sticking with a fixed raker depth, 0.025:, 0.035" or 0.045" for the life of the cutter will not give the fastest cuts. The raker depths have to increase during the life of the cutter by quite a large amount to maintain cutting speed. This is called progressive raker setting.
I read about this in the The Carlton Complete book of saw chain. (
http://www.sawchain.com/images/complete book.pdf) and then experienced it for myself with milling very hard aussie wood some of which is twice as hard as pecan.
The way to approach this is to work with cutter angles as described in the Sticky.
In practice an example is if your chain is cutting well when it is new then measure your gullet width (typically 0.25) and your raker depth (typically 0.025") and then stick with that ratio (10:1) during the life of the cutter. When the gullet reaches 0.35" the rakers need to be 0.035, when the gullets reach 0.040" the rakers should be set to 0.040 etc.
There is nothing special about the 10:1 ratio, some people find 10:1 produces too much vibe while others find it too wussy. Whatever ratio you pick if it works then sticky with that thru the life of the cutter and it will always cut well provided the cutters are sharp..
The Carlton File-O-Plate does the same thing except it only uses a ratio of 13:1 which I reckon is too wussy. I also reckon it's not truly progressive anyway
How this is achieved is up to the operator. Some operators use grinders to set their rakers but then they really need to round over anyway so if the operator have to pick up a file to do this I find I might as well do it with a file (yep even the 96 cutter chains I do by hand). Using a single gauge is not possible so one possibility is to buy a set of gauges (025, 030, 035, 040, etc). Some people use feeler gauges but I find that is too fiddly so I now use a digital angle finder (DAF) and a file - see post #68 in the sticky for a link to a video of how I do it. In practice I only set the rakers with a DAF about after every dozen touch ups and in between I take a couple of swipes at the rakers with a file.
I use a ratio of 11:1 on loprochain, 10:1 on 3/8 and 9:1 on 404, in hardwoods. Some of my gullets are now around over 0.45" mark and the chain cuts as good as when it was new. There is no extra load on the saw because it is just like running a new chain all the time. In fact it is good for the saw because operators will not need to push it anywhere near as hard as before.
Of all the mods and farting around with saws and different chains etc I have done I'd say this is by far the most significant improvement I have made to my cutting.