how much power is lost using a hard nose bar?

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GASoline71

GASoline71

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2" longer than what???

Long bars whether hard nose or sprocket nose will cause your saw to work harder resulting in a little power loss...

You have to know how to adjust your sawin' techniques to use longer bars.

The "power loss" between hard nose and sprocket nose bars is negligible... But like Pest said... you also have to know how to adjust chain tension for each bar type. Also make sure that oiler is workin' well...

Gary
 
djmercer1

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2" longer than what???

Long bars whether hard nose or sprocket nose will cause your saw to work harder resulting in a little power loss...

You have to know how to adjust your sawin' techniques to use longer bars.

The "power loss" between hard nose and sprocket nose bars is negligible... But like Pest said... you also have to know how to adjust chain tension for each bar type. Also make sure that oiler is workin' well...

Gary

i think what he meant was was is a 18" hardnose roughly equal to a 20" sprocket nose.

my related question here is how much power does the bar actually rob? what i mean is, if you are to cut a 12" stick with 18" and a 24" bar how much do you lose to the bar?

also, when people say that a saw with so many cc's can only handle a bar of a particular length(im pretty sure that a 50cc saw can pull the chain of a 60" bar, but just not in a material that is very hard/tough), i assume that they mean that the bar is nearly buried, yes/no?
 
Wood Doctor
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You would actually gain power with a solid nose if the sprocket nose bar decided to gum up. On occasion some will without a proper lube. Suddenly half your horsepower evaporates, and the situation can worsen to the point where the engine cannot even rotate the roller in the nose, let alone cut wood. Even using the right bar and chain oil can't solve the problem. Moly grease crammed into the nose fitting, of course, can.

BTDT :cry:
 
GASoline71

GASoline71

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i think what he meant was was is a 18" hardnose roughly equal to a 20" sprocket nose.

Thanks... I undersatnd what he means now... :)

my related question here is how much power does the bar actually rob? what i mean is, if you are to cut a 12" stick with 18" and a 24" bar how much do you lose to the bar?

also, when people say that a saw with so many cc's can only handle a bar of a particular length(im pretty sure that a 50cc saw can pull the chain of a 60" bar, but just not in a material that is very hard/tough), i assume that they mean that the bar is nearly buried, yes/no?

Take a 16" loop of chain... and hold it in one hand. Take a 32" loop of chain and hold it in the other. Big weight difference. Takes more umph to get that mass rollin' and keep it rollin' "buried" or not.

Gary
 
BlackCatBone

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Take a 16" loop of chain... and hold it in one hand. Take a 32" loop of chain and hold it in the other. Big weight difference. Takes more umph to get that mass rollin' and keep it rollin' "buried" or not.

Gary

Yup, and since the longer chain is more massive, you end up with slower chain speed, quite a bit slower. Engine power is a constant and the chain energy is a product of mass and the square of velocity (.5MV^2)....carry the one:dizzy: much slower chain.
 
djmercer1

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Thanks... I undersatnd what he means now... :)



Take a 16" loop of chain... and hold it in one hand. Take a 32" loop of chain and hold it in the other. Big weight difference. Takes more umph to get that mass rollin' and keep it rollin' "buried" or not.

Gary

my intent of the question was considering that we have a 066 at work we use with a 48" bar cutting ice and styrofoam. the 066 can pull the chain that long but i think it would in tough to perform if the material was tough like a hardwood, as opposed to ice/styrofoam. i liken this to the 18" bar on the wild thing, sure it can pull in air, but add the resistance of the wood and the saw cant perform properly with that length of buried bar.

is there any quick calculation to perform to determine needed power for chain length, i thinking like a nomograph chart, similar to performing a rim pull calc for a piece of equipement. also, is there a source of power/torque curves for chainsaws, particularly the 051 and 048 stihls?
 

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You use a 48 inch solid nose?

A solid nose cutting ice is a drag.......almost impossible to get the chain tension right I used to carry an XL for ice fishing and ice heave removal.

Roller tips are much better suited for ice.....don't know on Styrofoam as I never tried it...
 
djmercer1

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A solid nose cutting ice is a drag.......almost impossible to get the chain tension right I used to carry an XL for ice fishing and ice heave removal.

Roller tips are much better suited for ice.....don't know on Styrofoam as I never tried it...

no, its not a hardnose, its a stihl es. we use it for cutting slots in ice for compressive strength testing of pack ice. the question of the long bar on the 066 was relative, i dont think it can really pull it in tough wood but in styrofoam and ice its ok, almost under powered, which is why last season we bought a 880 for the 5' and 8' bar.
 

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