# Best 60" Bar for milling



## Barthaigh (May 13, 2010)

Hi, I am looking for a 60" .375 / .063 gauge bar for my 3120xp. I was wondering if anyone has a any suggestions. I found a woodland pro and a GB titatanium. Are either of these better bars, ie stiffer, better wear etc. thanks for any input, Bart


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## HUCKLEBERRY (May 13, 2010)

I recently purchased a 42" GB bar for my procut style mill and here is a little feedback from my experience.
-Price - @ $80 to my door new/unused off of Ebay
-Universal fit - the one I purchased will fit many saws with the use of different "bushings"
-Nose sprocket allows the use of either .375 or .404 pitch chain
-Appears to be of quality construction but I'm just now getting my mill finished so no feedback on longevity

The bad- I don't think that GB has a very strong US prescence but in the case of a chainsaw bar that wasn't a big deal for me.

Good luck........I sure wish I had a 3120xp to put on the end of my bar!


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## mtngun (May 13, 2010)

HUCKLEBERRY said:


> -Nose sprocket allows the use of either .375 or .404 pitch chain



How does that work ?


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## HUCKLEBERRY (May 13, 2010)

mtngun said:


> How does that work ?



I guess roller tip might be a better name for what my bar has than nose sprocket because it has no teeth. Bar looks a bit like a solid tip with a thin pulley riveted in it.


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## mtngun (May 13, 2010)

OK, roller tip. I wouldn't mind having one of those for my 084. Which seller did you buy it from ?


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## Brmorgan (May 13, 2010)

mtngun said:


> How does that work ?



Ya, I was wondering the same???


For the ultimate in durability and stiffness, it would be hard to beat a Cannon Superbar. The ones already mentioned have good reputations as well though.


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## Deets066 (May 13, 2010)

it would be hard to beat a Cannon Superbar. :agree2:

and bart just so u know cannon superbar and the woodland pro are the same bar


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## HUCKLEBERRY (May 13, 2010)

mtngun said:


> OK, roller tip. I wouldn't mind having one of those for my 084. Which seller did you buy it from ?



mtngun,

Man I apologize but after looking for an hour I can't find any record of that purchase, which lets me know two things. Even though I'm positive I got it off the net/by mail it wasn't Ebay and it wasn't as recent as I remembered either. I'll keep looking and if I can find the info. I'll get it to you.


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## BobL (May 13, 2010)

I would be interested to know the amount of sag the cannon superbar has when it laid flat horizontally.

BTW I have noticed my magnetic anti sag device is losing its magnetic holding power. I suspect this is because it is being vibrated by being permanently mounted on the mill. 
Alternatives are 
- remove from mill every time ie PITA
- replace magnet every so often, could be expensive
- change to another system?


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## Deets066 (May 13, 2010)

BobL said:


> I would be interested to know the amount of sag the cannon superbar has when it laid flat horizontally.
> 
> I have a 50" superbar/woodland pro could check tomorrow, i know it sags some but couldn't tell ya how much


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## hazard (May 14, 2010)

BobL said:


> - change to another system?



Could you create something that pushes up from the bottom that is adjustable along the rails that are parallel to the bar?

I am of no help on the bar question. sorry


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## BobL (May 14, 2010)

Deets066 said:


> BobL said:
> 
> 
> > I would be interested to know the amount of sag the cannon superbar has when it laid flat horizontally.
> ...


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## Can8ianTimber (May 14, 2010)

I love my 60" cannon superbar and wish I had a 60" as well. My 60" bar is a cheapo and 60" is the most common length I use. Oh well, 

My vote is Cannon


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## DaltonPaull (May 21, 2010)

I'm going to have my next bar (60-70" haven't decided) custom made locally by chain bar repair in Milwaukie. They make the best looking milling bars I've ever seen and have pretty reasonable prices too. They make the bar extra wide (8" or so) in the middle for lower sag. According to the owner, they make the bars Grainberg sells. You might want to call them for a quote.


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## BobL (May 21, 2010)

DaltonPaull said:


> I'm going to have my next bar (60-70" haven't decided) custom made locally by chain bar repair in Milwaukie. They make the best looking milling bars I've ever seen and have pretty reasonable prices too. They make the bar extra wide (8" or so) in the middle for lower sag. According to the owner, they make the bars Grainberg sells. You might want to call them for a quote.



That's interesting because extra width doesn't normally help sag, not even a little. The main reason for making them wider in the middle is to reduce the chances of the chain shooting off the bar when the bar is held horizontal.


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## Daninvan (May 21, 2010)

BobL said:


> The main reason for making them wider in the middle is to reduce the chances of the chain shooting off the bar when the bar is held horizontal.



OK Bob, can you help me out here, why does making the chain wider reduce the chances of the chain coming off when the bar is horizontal?


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## gr8scott72 (May 21, 2010)

Daninvan said:


> OK Bob, can you help me out here, why does making the chain wider reduce the chances of the chain coming off when the bar is horizontal?



Not making the chain wider, making the bar wider at the middle. That's what helps keep the chain on a longer bar.


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## BobL (May 21, 2010)

Daninvan said:


> OK Bob, can you help me out here, why does making the chain wider reduce the chances of the chain coming off when the bar is horizontal?



It's not the chain that is wide - its the bar that is wider.

When a chain is driven round a sprocket it experiences a centrifugal force that makes it want to jump away from the sprocket. 

Counteracting that is the chain tension which keeps the chain pulled down onto the sprocket and bar. 

In addition the pull of the sprocket pulls the chain into the pickup side of the sprocket and generates less tension on the chain on the outgoing side. 

The reduced tension on the outgoing side combined with the centrifugal force can (if the chain is loose) lift the chain drive links right out of the bar groove. The chain forms an shallow arc through the air before it dives back down by overall chain tension. 

When the bar is held vertically as in bucking this is less of a problem as gravity helps hold any loose outgoing chain down on the bar.
If the chain/bar are laying on their side the chain can droop off the bar and if a drive link hits a rail top the chain can jump the bar.
The problem is worst when the bar is still cool and the chain is hot, like at the beginning of a cut

The problem is greater for long straight bars which leave little room for error in chain tension adjustment or stretching.

If a bar is made with some additional arcing width, the shallow arc of chain lifting off the bar generated by the drive sprocket is more closely matched to the bar than for a straight bar and so the chain more easily stays on the bar. That's why racing bars have such curved bar width profiles.


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## DaltonPaull (May 21, 2010)

It's possible that I misunderstood the purpose of the extra width. Now that I think about it, the bar would be stronger but also heavier so it might have similar sag. I'll have to ask them about that. My memory has them substantially wider than the WoodsmasPRO bar above.

I forgot to mention that all the bars that I,ve seen in their shop are double ended for use with a helper handle. I'm not sure if they can put a tip on them or not.


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## BobL (May 21, 2010)

DaltonPaull said:


> It's possible that I misunderstood the purpose of the extra width. Now that I think about it, the bar would be stronger but also heavier so it might have similar sag.



That's what happens. 

One can of course make bars out of even stiffer steel but most brand name bars are already close to the limit of steel in that regard.


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## DaltonPaull (May 22, 2010)

One thing they told me is that they use completely hardened material, as opposed to bars that are induction hardened only at the edge were the chain rides which I guess is the typical way of doing things. I'm not sure if that makes them stiffer or not.


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## BobL (May 22, 2010)

DaltonPaull said:


> One thing they told me is that they use completely hardened material, as opposed to bars that are induction hardened only at the edge were the chain rides which I guess is the typical way of doing things. I'm not sure if that makes them stiffer or not.



That will make a significant difference.


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## mtngun (May 22, 2010)

DaltonPaull said:


> One thing they told me is that they use completely hardened material, as opposed to bars that are induction hardened only at the edge were the chain rides which I guess is the typical way of doing things. I'm not sure if that makes them stiffer or not.


Modulus of elasticity, which is what determines "stiffness," is the same, hardened or not. 

60" is a big bar.  Post some pics when you get to milling those big trees.


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## BobL (May 22, 2010)

mtngun said:


> Modulus of elasticity, which is what determines "stiffness," is the same, hardened or not.



I'm not sure what you mean. Modulus of elasticity is used to determine tensile strength and since there is a good correlation between tensile strength and hardness a harder material is usually much stiffer. So hardened bars will usually be stiffer than non hardened bars.


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## mtngun (May 22, 2010)

BobL said:


> I'm not sure what you mean. Modulus of elasticity is used to determine tensile strength and since there is a good correlation between tensile strength and hardness a harder material is usually much stiffer. So hardened bars will usually be stiffer than non hardened bars.


Hmmmm........ someone has been in management too long.  Going to meetings, writing reports, making powerpoint presentations ....... that'll rot your brain.  Good thing you have a stimulating hobby.  

Modulus of elasticity is the slope of the stress/strain curve in the elastic region. Most carbon steels have roughly the same modulus of elasticity, heat treated or not. 

Tensile strength, or yield strength, refers to the stress that would cause _permanent _deformation -- in other words, if you bent your chainsaw bar so much that it stayed bent and wouldn't spring back to shape. 

A heat treated steel will have a higher tensile strength, and will better resist permanent deformation (and better resist wear), which is all well and good, but that's not what we are talking about. We are talking about the bar temporarily sagging when it is laid on its side -- that's _elastic_ deformation, governed by the modulus of elasticity.

If you wanted to make the bar sag less, you would need either a higher modulus of elasticity (i.e., make the bar out of carbide rather than steel), or a higher area moment of inertia (i.e., a thicker bar).

wiki on bending stiffness for nuclear physicists who spend too much time going to meetings

wiki on modulus of elasticity

Are you back in Oz yet ? Done any milling lately ? It's still raining and snowing here, so I'll stay home and tweak my CSM.


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## BobL (May 22, 2010)

mtngun said:


> Hmmmm........ someone has been in management too long.  Going to meetings, writing reports, making powerpoint presentations ....... that'll rot your brain.  Good thing you have a stimulating hobby.
> 
> Modulus of elasticity is the slope of the stress/strain curve in the elastic region. Most carbon steels have roughly the same modulus of elasticity, heat treated or not.
> 
> ...



Yep, I agree, correct on all counts!  Now its all coming back to me. In fact I even remember annealing some old files many years ago and and being surprised at how stiff they still were.

Yeah back in Oz, heaps more meetings, paperwork and bovine excrement to deal with.
We're leaving for PNW in a week so getting ready for all that at the same time is no fun.

Might sneak off to the milling yard today but its raining (at last) here too so can't see myself getting to much done.


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