Raker Depth???

[rahtreelimbs]

I have heard some members saying that they can get away with more raker depth on their modded saws. How is this determined?

When you lower the raker depth you are taking more wood with the cutter. At the same time slowing the saw down a bit ( if I have this right ). Almost seems like it is a catch 22.

On the other hand, I believe Gypo does this on some saws, some take the raker depth the other way. This will make the saw run a bit faster.

What is up with all this???

 

[JimL]

they might be able to pull it, but its a ruff cut.
like full skip on a 24" bar..

 

[TonyM]

To get the optimum cutting speed, the load on the saw (torque) has to match the torque generated by the saw at maximum horsepower. Too much or little load will cause the RPM's to be below or above the RPM's at maximum horsepower. An easy way to change the load is change the mechanical advantage through drive sprocket sizes. Another way is to increase or decrease the chip load.

 

[jokers]

Hey Rich,

I might be wrong so hope to stand corrected, but from what I understand, a guy would take a race prepared chain and make timed cuts, lowering the rakers after each cut or two until the time was at it`s lowest. Of coure you don`t know what was fastest until you`ve gone past it, but that shouldn`t be a big deal, just re-file the chain. I`m figuring that there is a break even point and a point of no return in the relationship between raker clearance and chip clearance, and once the max raker clearance is in sight, you might want to work with different rims to get more chain speed while maintaining your speed in the cut. Maybe I`ve got the sequence wrong but I know that I can get there from here. Of course you need some reliable means of lowering the gauges incrementally.

Russ

 

[tony marks]

my 028 barbed wire special,would im sure cut pretty well with a 35 depth on gaugeand stil hold rpm.. but fast is fast .. besides my dog likes smaller chips as bedding..i say this from memory. dang back wont staiten out so if i saw at all its the 026.
rich with the saws u got... a little experimenting and u would be an authorfity on the subject. i wood think.
ps im beginning to get a real resentment thang of all you young men..aint whipped yet tho
d-- smazrt alecs

 

[Wade Huggins]

Who really knows????

Everybody seems to have there own opion I guess if your like me you just find your nitch and go with it. I have been around this business all my life and I didn't learn how to sharpen because I was smart........ I learned from the standpoint that if your saw aint sharp it wont cut and that sucks..........you just kinda pick it up through trial and error and everybody's technique is a little different so what works for you may not for me. When I am in the woods with a new chain I like to run my rakers @ .27th and try to keep them there until I get to the economy run part of the chain........ you know the part of the chain where you try to squeeze just a few more board feet out of it.....then at that point I usually knock the rakers back to .30th unless I am really cutting something hard like maple, hickory, younger growth timber. There is certainly a wide variety of opions on how much to shave off though. I will say this scince I have joined this site I have got to see the scientific side of chainsaws and their applications.........so much fun............Wade