Someone please explain what chain guage is all about

[coveredinsap]

Irrespective of the attempted derail into "engine spec's and mufflers", you still haven't answered the basic question of how your metalworking skills were used to increase the bar groove width, and how you'd propose to do that to accommodate 080 harvester chain....

What's it matter? There is any number of ways to do it, depending on what is needed to be accomplished. As long as you can get a straight groove that will properly fit the .080 drive links, where's the problem?
It can be as simple as files, a spacer and sandpaper. As I said, it's a groove in a steel bar...not the space shuttle.

 

[Griner Bros.]

I did a little reasearch and came up with nothing. I see .50 and .58 and .63 guage chain and bars for sale. I know they have to be matched. Why do they make different guages? Is one more durable or something?

 

[belgian]

What's it matter? There is any number of ways to do it, depending on what is needed to be accomplished. As long as you can get a straight groove that will properly fit the .080 drive links, where's the problem?
It can be as simple as files, a spacer and sandpaper. As I said, it's a groove in a steel bar...not the space shuttle.

Sap, How many weeks are you going to need to widen that groove with sandpaper ? What tolerances do you will end up with ? Any safety concern ?

I rather buy a new bar before I even consider to start the work you propose .
Roland

 

[Ekka]

If you tried to open up that groove in a bar with a nose sprocket then you'd be in deep ****. How would you do that?

I'm no bar manufacturer but from what I tell the bars are made in 3 parts, 2 outer on an inner, the inner being the thickness of the groove .... I see this on all the bars I have, and that's how the sprocket is inserted.

Also the bars are slightly curved so milling it would be near impossible.

Nope, I cannot see it done.

Are there any bars that are actually made out of one solid piece and the groove machined? If there is the nose must be sprocketless. Close up pics if you have one coz I aint seen one.

I also understood that Husky were the 0.058" fans and Stihl were the 0.063" fans ... but competition and interchanging may have forced bar and chain manf to make a mixture.

The 0.050" for saws above say 026 is rare here. I dont think I've ever seen a bar available for say a 046 running 0.050" guage here.

I honestly doubt the validity of going up in chain guage to fit a worn bar .... that does sound like BS to me.

Didn't you get banned Sap?

 

[Lakeside53]

What's it matter? There is any number of ways to do it, depending on what is needed to be accomplished. As long as you can get a straight groove that will properly fit the .080 drive links, where's the problem?
It can be as simple as files, a spacer and sandpaper. As I said, it's a groove in a steel bar...not the space shuttle.

hmmm... That's the best you could come up with? 0.017 in hardened steel with sandpaper. What about the depth? You of course ignore the sprocket issue or the physical dimensions of the .080 chain.. Give me a break... This is starting to sound like your posts on grinding steel... or your posts on air filters , or ...

Your reply speaks for itself... or should I say, for you.

 

[Lakeside53]

Are there any bars that are actually made out of one solid piece and the groove machined? .

Stihl ES bars (other manfs also have similar lines) are made of a solid section of steel that is machined out before zone hardening of the rails. The replaceable tip is made separately. The standard bars are three pieces laminated together. It's a trade off of weight verses strength.

 

[046]

I agree with lakeside. best way to take care of a worn bar is to either replace it or close it up with a Silvey bar closer. it's best to use a new chain as thickness guage.

then draw file to restore 90degree angle. been thinking of making a jig to dress edges on my belt grinder.

 

[Kneejerk Bombas]

The thinner the gage, the stronger the system.
050 chain is 063 when measured at the top of the drive link, only the lower part of the drive link is stamped down to .050".
If you measure the bar, on a one piece bar, like a Stihl ES, the bar thickness is the same for all gages, in a give pitch. Only the grove thickness changes.
A wider bar grove means the rails are thinner. The rails are the major wear point of the system.
Thicker rails, less wear.
Chain weight is a big factor in performance. It takes more power to move more weight. Chainsaw racers take extraordinary steps to lighten their chains.
Thinner chains cut faster. A thinner kerf means less wood to remove, hence less power needed.
When you move up a pitch, you'll gain some durability, but you lose cutting speed because of weight and kerf size.
Customizing a chainsaw bar is often done with what is called a Barshop Tool. It's just a specialized milling machine for making and modifying bars.
I've never tried it, but it seems like it would be pretty simple to modify a bar on a standard milling machine.

 

[coveredinsap]

It took me about 4 hours to fix the old Mac hardnose bar to work properly with the .404 .063 chain, including removing the rust, some dents, fixing some pinched areas, and cleaning and widening the groove with sandpaper. 100 grit followed by 240 grit worked well. It also took some file work on the base of the bar where the chain engages the bar from the sprocket to ensure the chain ramped properly onto the bar. The end result was it looked like it came from the factory that way.

Of course a sprocket nose bar wouldn't work without fabricating a new sprocket.

And of course it would be preferable to buy a new bar for the Mac...but they don't seem to make bars for old Macs these days, nor do they make them for chainsaws in .080.

I would probably take a different route if I was going to fabricate a chainsaw bar in .080 ....I would try to find a harvester bar that I could alter the mount to fit to the chainsaw.

You folks who naysay can just stick to buying your bars in the exact configuration you need.

As I said, a man's got to know his limitations.

 

[v8titan]

Thicker rails, less wear.
Chain weight is a big factor in performance. It takes more power to move more weight. Chainsaw racers take extraordinary steps to lighten their chains.
Thinner chains cut faster. A thinner kerf means less wood to remove, hence less power needed.
When you move up a pitch, you'll gain some durability, but you lose cutting speed because of weight and kerf size.

A while back I collected some data on 0.050 and 0.063 3/8 RS chain. I used an accurate balance to measure the weight difference... here's what I found:

Chain#1 72 link, 3/8, 0.063, RS (sharpened once by file), weight = 365g
Chain#2 72 link, 3/8, 0.050, RS (never sharpened), Weight = 359g.

As you can see, this weight difference is insignificant somewhere around 1%. This makes sense because if you put things in perspective, going from .050 to .063 is the difference in thickness of 4 sheets of copy paper. A sheet of copier paper is about 0.003". I find it hard to believe that this small change in weight would have a big impact on performance..cutting speed..etc.

As far as wear, I don't think gauge has anything to do with it. The amount of drive tooth in contact with the bar is the same for both gauge chains.

My $0.02

Tom

 

[Ekka]

Yeah lakeside, I have Stihl rollomatic ES bar's on my 66 and 46, so they're one piece, good news.

Is there a 0.050" 3/8 sprocket nose bar to fit a 46 or 66?

And who makes the corresponding chain for it?

And if I fit one of those bars what about the rim drive sprocket, is that OK to stay the same?

Oh, I use 22" and 24" bars

 

[THALL10326]

Yeah lakeside, I have Stihl rollomatic ES bar's on my 66 and 46, so they're one piece, good news.

Is there a 0.050" 3/8 sprocket nose bar to fit a 46 or 66?

And who makes the corresponding chain for it?

And if I fit one of those bars what about the rim drive sprocket, is that OK to stay the same?

Oh, I use 22" and 24" bars

Get yourself a 3003-000-8830 20in for the 046 with a 33rs72 chain.
A 3003-000-9630 24in. for the 066 with a 33rs84/85 chain and watch them
saws take off. The sprocket drive on the saw stays the same, all 3/8, bar, chain and sprocket..................

 

[coveredinsap]

As long as the drive sprocket on the chainsaw is 3/8 pitch, you can use any gauge bar and chain...as long as the bar and chain are both the same gauge (and 3/8 pitch).

I'm not familiar with Stihl products, so someone else will have to answer that one for you.

 

[Kneejerk Bombas]

Yeah lakeside, I have Stihl rollomatic ES bar's on my 66 and 46, so they're one piece, good news.

Is there a 0.050" 3/8 sprocket nose bar to fit a 46 or 66?

And who makes the corresponding chain for it?

And if I fit one of those bars what about the rim drive sprocket, is that OK to stay the same?

Oh, I use 22" and 24" bars

Stihl makes a 25", 84 Drive link, 3/8", 050 bar. And they make a 20" 72DL, 3/8s, 050. Both fit the 046 and 066.

All the sprockets, and bar sprocket tips, fit up to 063 chain, so those are the same no matter what gage you run.

 

[Kneejerk Bombas]

.

As far as wear, I don't think gauge has anything to do with it. The amount of drive tooth in contact with the bar is the same for both gauge chains.

My $0.02

Tom

The wear occurs between the bar, and the bottom of the cutter and tie straps. That's where the wider surface area helps, not down in the bar grove.

 

[coveredinsap]

The wear occurs between the bar, and the bottom of the cutter and tie straps. That's where the wider surface area helps, not down in the bar grove.

Hmmmm. If that was the case then worn bars wouldn't have a wider groove....which they do.

No, it appears the whole rail/groove area wears...anyplace where two metal surfaces can rub together.

 

[Kneejerk Bombas]

When one rail wears more than the other, this cocks the drive link in the grove and then the grove wears. The grove wears after the rail.
This is why dressing the bar rails is such critical maintainance. As long as the rails are flat, the bar grove will stay true, but once the grove goes out of whack, the rails will quickly wear, even after proper dressing.
Closing the bar rails can give the bar a temporary fix, but if the inside of those rails is worn, the bar is junk.

 

[Lakeside53]

It took me about 4 hours to fix the old Mac hardnose bar to work properly with the .404 .063 chain, including removing the rust, some dents, fixing some pinched areas, and cleaning and widening the groove with sandpaper. 100 grit followed by 240 grit worked well. It also took some file work on the base of the bar where the chain engages the bar from the sprocket to ensure the chain ramped properly onto the bar. The end result was it looked like it came from the factory that way.

Of course a sprocket nose bar wouldn't work without fabricating a new sprocket.

And of course it would be preferable to buy a new bar for the Mac...but they don't seem to make bars for old Macs these days, nor do they make them for chainsaws in .080.

I would probably take a different route if I was going to fabricate a chainsaw bar in .080 ....I would try to find a harvester bar that I could alter the mount to fit to the chainsaw.

You folks who naysay can just stick to buying your bars in the exact configuration you need.

As I said, a man's got to know his limitations.

You just had a worn out bar to start with... Quite different from "machining" a bar to take a wider chain... Good luck on getting sandpaper to grind out the stellite you'll find on most hard nosed bars - I believe my old MAC even has stellite.

BTW, Why in the world would you want to run a 0.080 bar on a chainsaw? What pitch chain would you run? 3/4? Heck, why not run the 0.122 harvester bars. I guess you've never seen either in the flesh.

 

[Lakeside53]

When one rail wears more than the other, this cocks the drive link in the grove and then the grove wears. The grove wears after the rail.
This is why dressing the bar rails is such critical maintainance. As long as the rails are flat, the bar grove will stay true, but once the grove goes out of whack, the rails will quickly wear, even after proper dressing.
Closing the bar rails can give the bar a temporary fix, but if the inside of those rails is worn, the bar is junk.

Couldn't have said it better myself!

It also wears the chain tangs tapered as well as the straps if the bar inside is cocked... Just "fixing" the bar with out new chain is often folly..

 

[RaisedByWolves]

. been thinking of making a jig to dress edges on my belt grinder.

I do this and it works well for me. You need to deburr the entire bar first, then use a machinists square to square the platen(where the work sits) with the backplate(where the belt rides).


Using light pressure you want to just gently reshape the bar. Youll know when your using enough pressure when it seems like it is taking too long.


After 3-4 passes over the entire length you will most likely wind up with 1-2 spots that arent dressed yet, take your time and work the entire bar until they come up.


It takes finesse and care to avoid leaving marks near the sprocket or grinding the sprocket its self but after some practice youll get it.