Why is a wide nose bar better?

[cgraham1]

I have a 20", and a 36". The 20" came with my 064 when I bought it.

 

[Al Smith]

Bigger is better.

Depends on the subject matter .

 

[darkimpulse]

I've always heard that they're better, but are they really?

More girth is always better, at least so I am told.

 

[Mastermind]

The wide nose bar probably has one more tooth on the idler. That mean it will run at a lower RPM. That would translate into a longer bearing life.

In theory at least.

 

[heimannm]

The chain make a slightly less dramatic change of direction when going around a wide nose bar so it does go a bit more smoothly. With hardnose bars is also reduces the pull on the nose (spreads it out over a wider area) so the bar tip will last longer. I have only seen a very few hardnose bars that ever worn out the stellite on the nose.

Mark

 

[jmssaws]

I have many wide nose stihl bars and the only thing I don't like about them is if your chain is aggressive at all it makes punch cutting with the nose almost impossible. Like I said earlier it's supposedly for boring but it's not good for it. The narrow nose is much easier to bore with.

A mean chain and a wide nose is hazardous to a man's health.

 

[Workshop]

I always figured the narrower tip was to help reduce kick back.

 

[sunfish]

Wider is not better, it's just wider...

 

[Philbert]

The main reason is reduced friction.

Pulling a chain (rope, cable, etc.) around a larger radius curve reduces friction/resistance, and therefore, heat, wear on the bar, strain on the motor, etc. With a sprocket nose, a larger radius means that they can pack a few more bearings in there as well.

The larger radius also provides a larger area (lower quadrant) that you can bore cut with. The downside, is that it also provides a larger area (upper quadrant) subject to kickback. Some manufacturers tried to address this by making 'banana bars' that had an asymmetrical tip (smaller radius on the top, larger radius on the bottom).

Larger radius bars s*ck for carving.

Many guys probably want them just because they can't get them anymore, so some sellers may try to jack up the price, based on scarcity.

Philbert

 

[Philbert]

Top to bottom:
- standard 'small' radius bar;
- 'dime-tip' carving bar;
- roller nose bar;
- 'banana bar'!

Philbert

 

[Deets066]

Well put

 

[CR888]

Chain is heavy and modern saws rely on chain speed much greater than saws of years past. Tha rapid change of direction on a small radius may reduce kick back significantly but robbs power in doing so. It means the sprocket has a harder life too but studies over many years show a huge reduction in kick back related injury when using smaller radius noses. You can always replace a bearing or improve a saws power to make up the small amount that is lost. Telling a sawyers wife why her husband is in the emergency dept is a little more difficult to explain I guess.

 

[jake wells]

is this a wide nose?

 

[CR888]

The number of teeth in the sprocket will answer the question above, I think the stihl ES wide noses were 13 teeth opposed to 11 on the new standard ones.

 

[Philbert]

This is a wide nose . . .



Philbert

 

[srcarr52]

A regular 3/8 tip had 11 teeth.
Old school Oregon large 3 rivet tip was 12 teeth, the 3 rivet tip for shorter bars was still 11 theeth.
Stihl wide tip is 13 teeth.

Like any chain a larger radius sprocket is more efficient because their is less parasitic loss. For example, the chain has a centrifugal acceleration from traveling in an arc, the internal forces of the chain pins have to resit this, as the radius get smaller, the forces go up by a power of 2 and the loss due to fiction increase according to the pin force. As well that is not the only force associated with loss in the system that goes up as radius decreases.

 

[darkimpulse]

Only thing I have noticed is that narrow nose bars are good for reducing kickback while wide nose bars seem to have a much better boring performance.

 

[Philbert]

. . . the chain has a centrifugal acceleration from traveling in an arc, the internal forces of the chain pins have to resit this, as the radius get smaller, the forces go up . . .

Interesting. I was thinking only about cutting efficiency - never thought about different wear on the chain!

Philbert

 

[cgraham1]

So, is the wide nose better?

 

[maulhead]

The reason I ask, is that I saw a wide nose for sale somewhere and the guy wanted twice what a standard ES bar would cost... and now it's sold. Why would someone pay that much more for a wide nose bar over a standard bar?

Do you have a link to this wide nose bar that was twice as much?

I have a wide nose bar, and have noticed that it cuts smoother (less vibes) vs a regular ES bar of the same length. Switching back & forth, from the narrow to the wide nose bar, on the same saw using the same chain, I can tell a difference, the wide cuts smoother. The wide also is faster, not night & day faster, but it's noticeable to me.

Redbull did some test of wide vs narrow bars, If I recall correctly the wide had 8-9% faster cut times.....