chain tension

[woodturner]

Here's another neophyte question posted for your enjoyment. I'm sure you can get a few laughs out of it.

Manual says to tension so there's no slack at the bottom of the bar, and so the chain can be pulled easily around the bar.

1) Does this mean so the chain can be lightly gripped and still pull the chain around the bar?

2) What are the adverse effects of having the chain too tight? Maybe stressing the motor, and the bar, etc?

 

[luvbug1977]

Hey woodturner, never a dumb question. The only dumb question is the one not asked.

I was curious of the same question, but didn't want to seem "stupid". Hehe!

 

[Lewis Brander]

Chain Tension:

Hi, in my operators manuel for the Poulan, model 3400 AV, with Oregon chain and roller nose bar, it explains that you adjust the chain tensioner by lifting up on the tip of the bar, adjust the chain so that it just contact the bottom of the bar and turn the adjuster an additional 1/4 turn and tighten the bar nuts. I find that it seems a little snug when first trying to turn the chain by hand, but by the time you've made a couple of cuts it turns over fine. no drag. (Of course with the engine stopped.) This seems to work for me, not that I have ever used the saw that much. Lewis.

 

[tony marks]

to me this depends on whether its new chain or not.. while u dont want it too tite,,as this can put undue strain on every thing. a new chain is gonna stretch some at first.. so u have to allow for that and just plan on adjusting tension after u have run it half day or so.
otherwise while saws vary,,the most important thing to me is aftyer its been used bit,, is it still holdin in the rail pretty good.if a chain dont move smoothly on the bar,, cold or makes noise ,,u mite want to check and make sure every things a match ,and u sprockets are good. good luck.
an example of a problem ,,would be running say an oregon power match
sprocket on an stihl saw. its works ,just not to well. best change every thing out or go with stihl sprocket an every thing else.good luck.

 

[glens]

It really comes down to personal preference and for me, just tight enough so the chain doesn't feed off the bar tip at the slightest provocation works best.&nbsp; It usually amounts to snugging the tensioner until the chain sideplates <i>just</i> contact the bottom bar rail, with the bar tip lifted.&nbsp; My concept of how it should be is that the chain works best at the point it's most flexible yet sufficiently guided.&nbsp; I snug it up a bit extra for filing, though.

One other aspect to consider is that when cutting with the top of the bar, all the chain slack will be concentrated between the drive sprocket and the wood.&nbsp; You don't want so much slack that the sideplates excessively hammer the bar rails on the infeed in such a case.

Glen

 

[Husky372]

i was tought that tighten it so that when you pull up on it it just comes out of the rails. right or wrong? seems everyone has different opions on this.

 

[Lawn Masters]

My method is to tighten the chain so that it has the space of a dime between the bottom of the tie straps and the bar rails. this way there is room for some contracting when the chain cools off.

Also, if you have a relatively tight chain, when you finish you NEED to have some slack in the chain to allow for it to shrink again as it cools, if you keep it tight all the time you will most likely have to replace the crankshaft seals and/or bearings, the cause of this is that when the chain cools and contracts it will pull on the crankshaft and cause damage to the bearings and seals. Its a generally unpleasant thing to have to replace the bearings and seals plus a chain sprocket and sometimes a clutch drum if running a rim style sprocket.

 

[woodturner]

This past weekend I heard a chainsaw & looked to see my neighbor along with a lawn service guy cutting down a shrub. He was using a Husky 351. I don't know much about c/s's but I do know that this guy apparently don't know'em either. This guy's chain was drooping off the bottom of the bar, what appeared to be at least an inch! I couldn't believe it!! Even I know better than that.

I think I'm gonna remove the chain & do the chain soak, and based on what ya'll think, maybe loosen the chain tension a bit.

When I installed this new chain, I got it fairly tight, & I can still pull it around the bar, but it requires quite a firm grip on the chain to do so. Keep in mind, on the first tug, to pull it around the bar, it doesn't slide around the bar smoothly, but, upon kep on pulling around the bar a couple more times, it moves smoother, with each successive pull. And, I can still pull it off the bottom of the bar slightly, with just a gentle tug, as the manual states. So, With this description, do ya'll think it's too tight, or are you just confused by now?

 

[woodturner]

Hey, Luvbug,

I've got a 350 stock saw too.

 

[sedanman]

Here's how I do it. I hold the saw by the rear handle so the tip of the bar is resting on a hard surface, I tighten the chain so there is no slack on the bottom of the bar. Tighten (not gorilla tight) the bar nuts. The desired effect is no sag on the bottom of the bar and no or little drag when pulling the chain (use gloves) around the bar. Remember NO SAG/ NO DRAG!

 

[woodturner]

"No Sag- NO Drag

Kinda what I thought!

 

[mswabbie]

When you tighten a chain, if you lift the chain on the top of the guide bar, should you be able to see the bottom point of the guide link.
Thanks

 

[tony marks]

another factor that plays ,for me ..is what the saws gonna be doing..
for saws that are making quick cuts,ill leave some little slack ,mabe.. but in heavy cut ,u chain is going to go thru changes ,to the point that im gonna start with an chain as tite as will turn easily..because its gonna end up looser anyway..jmo

 

[WRW]

Husky372
Your method, while it may work for you, is somewhat subjective. The metal in a chain is elastic (don't believe me? bounce a ball bearing on concrete). Longer bars with longer chains will require less force to pull the chain the same distance (out of the rails) than a shorter bar & chain combo. Your level of force will also make a difference in how tightly the chain can be tensioned and still be pulled out of the rail.

I'm not saying you are doing it wrong, but, for describing how to do it right to a "neophyte", the description of "NO SAG/NO DRAG" nails it. Neat way to say it, sedanman!

 

[WRW]

OBTW, after adjusting, but before tightening all the way, I run the chain around the bar several times to make sure the chain on the sprocket lines up with the bar. Sometimes, I'll have to retighten the chain just a smidge before I call it "right".

 

[sedanman]

I've given the "talk" to a few hundred new chainsaw owners. This is the easiest thing for them to remember. You talk to them, show them the features and functions of the saw, beg them to read the manual and hope that something you said to them sinks in. "No sag, no drag" rhymes so maybe they remember it.

 

[Pacific]

For me I go roughly the middle of the bar and lift up on the chain if I can see 3/4s of the driver thats tight enough. Chain tension can only be described by feel I never had problems with blowing crank seals etc. When I install a new chain I snug it up tighter then normal run the saw up for 2-3 minutes the chain stretches abit so I retighten it to what I usually do.

I was showed how to set up the chain years ago by a guy with many years of experience. Its worked good for him and it has worked fine for me for the 11.5-12 years I have been working with saws.

I have seen people with chains too loose they are drooping down under the bar where you can stick your finger bettween the driver and bar. Then I see people with the chain so tight you can't lift the chain up off the top of the bar to expose the driver.

 

[RDP]

I adjust it so when I pull the chain on top it sticks out of the rail guide 1/8 to 3/16 of an inch and the bottom of the chain is pulled, drawn snug in the bottom rail, maimum depending on the chain size would be 1/4 inch. Not quite enough for the drive link toe & heel to pull out of the top of the bar slot completely. Too loose will get you cutting crooked on an angle.

 

[Lewis Brander]

Chain Tension:

Hello to all. In my previous post on chain tension adjustment, for my Poulan saw, that seems to work fairly well for that application. I've just got a new chain for the 5-20 Homelite. It's a new 1/2" pitch, .063 gauge, 52 DL of Oregon Chipper chain. It came with a chain repair kit and instructions. The instructions for that chain state to lift the end of the bar and adjust the chain so that there is 1/4" clearance (middle of the bar) between the top of the bar and the bottom of the chains connecting links. I've adjusted the chain that way and there seems to be no problem. I try to adjust it so that it is tighter and there seems to be a little binding when trying to pull the chain around the bar. The bar is an old bever tail hard nose bar that I've cleaned up (squared up by draw filling, etc.). To me it seems that the smaller the chain and if your running a roller nose bar, you can get away with running the chain a bit tighter. As sedanman says, NO Sag, NO Drag. With the hard nose bars it seems that a little clearance would be required, especially using larger pitch chain that appears to me not to give or stretch as much. I'm no saw expert, just drawing my conclusions from what I've read and observed on these old saws of mine. Looks to me like you would have to adjust the chain to your particulay application or desires (what works good for you). The 2 saws I have with roller nose bars, I can run the chain a bit tighter, when cold, but in the cut they will loosen up a bit. With the older saws with larger pitch chain, they don't appear to loosen that much, slower chain speeds and not that I've done a lot of cutting with the old saws. OK, rambled on enough. For those in doupt, I do like the No Sag, No Drag idea. My brother has had his chain jump off a couple times on his new Husky 372XP. He wasn't raising the end of the bar when adjusting chain tension and he was adjusting the chain so that it just touched the bottom of the bar. He now raises the bar and uses a bit more tension ( the chain can be pulled freely around the bar) and he hasn't had the chain jump off lately, excpt once when he pinched the chain in a cut. Take care. Lewis.

 

[geofore]

my brother/372

Two things to look at, one you mentioned lift the nose; the other is tighten the nuts on the side cover in order: the nut furthest to the rear first then the one closest to the front, it makes a difference.