Crofter
Addicted to ArboristSite
How do you suppose Stihl accomplishes this so called "pre stretching"? Could it be measured or is it merely a figure of speach? Do they do it with their advertising pen?
Prestretched Chain; Fact or Myth?
- Thread starter Crofter
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oldsaw
"Been There, Milled That"
Very common with motorcycle and industrial chains
They pull them a few revolutions under stress. I think it has more to do with not getting "tight" links than actual stretching, but it would take care of any extra "stretch" caused by ridges in any of the machined parts...the first time you used it. Essentially, it could save you one full adjustment during the life of the chain.
They pull them a few revolutions under stress. I think it has more to do with not getting "tight" links than actual stretching, but it would take care of any extra "stretch" caused by ridges in any of the machined parts...the first time you used it. Essentially, it could save you one full adjustment during the life of the chain.
sedanman
Just cut the piano!!
They DO pre-stretch their chain. By stretching a new chain you move all the rivets to end of their travel. Use will still burnish the rivet holes and move the rivets a little more. It's not totally broken in out of the box but it has a head start.
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oldsaw said:
So this is pretty moot?
oldsaw
"Been There, Milled That"
Just because Sedanman said "burnish" doesn't make
him smarter, he just used bigger words.
I'da usda biggr wurd if'n i'da thunk abowt et a bit morr. Mama alweez sed i'ze tha smert won en tha fammly.
him smarter, he just used bigger words.
I'da usda biggr wurd if'n i'da thunk abowt et a bit morr. Mama alweez sed i'ze tha smert won en tha fammly.
Crofter
Addicted to ArboristSite
So is stihl chain longer link to link, than other brands (even minutely) for having been prestretched? I dont question that Stihl is good chain, but is this supposedly freedom from initial loosening up really noticeable and measurable. I expect any new chain I put on to need retightening after several minutes of running without a load. Cant say I have noticed any brand to brand difference, but installing a new bar sure results in a loosening up!
MasterBlaster
TreeHouse Elder
Heat.
Crofter
Addicted to ArboristSite
yep, heat thins the lube film between rivets and drive tangs and metal to metal galling eats the rivets and holes causing the chain to grow longer. It is not that the chain is heated to the point that its tensile strength lowers enough to cause the tension to elongate the components.
woodshop
Addicted to ArboristSite
So oldsaw... they have a machine that literally puts tension on the chain and then runs if around a few cylinders to simulate the real thing? Wonder if they do this before or after they grind the tooth on it. This would be interesting to see... wonder if they give factory tours where they make the Stihl chain. Where do they make the chain anyway, anybody know? HEY... in Hershey PA where they make the chocolate bars, when you do the tour they give you bar of chocolate at the end. Wouldn't it be nice to tour the Stihl chain plant and get a loop of RS when you walk out?
Dave
Dave
So far as I know, Stihl still grinds the cutters before assembly.
Frank, can't you spin up a couple of loops of various makers' chain and hang them on a welding rod to compare lengths?
Maybe the pre-stretch is merely a happy byproduct of them rigorously testing the assembly as a means of quality control. In any event, in my experience a new Stihl chain stretches at about the same rate throughout its useful life while an Oregon requires a couple of quick, early adjustments when first put into service.
The pre-stretch in itself isn't worth anything to me, to speak of, if it were to cause the chain price to be higher, but overall the Stihl chains work enough nicer from start to finish that they're worth a bit more.
Glen
Frank, can't you spin up a couple of loops of various makers' chain and hang them on a welding rod to compare lengths?
Maybe the pre-stretch is merely a happy byproduct of them rigorously testing the assembly as a means of quality control. In any event, in my experience a new Stihl chain stretches at about the same rate throughout its useful life while an Oregon requires a couple of quick, early adjustments when first put into service.
The pre-stretch in itself isn't worth anything to me, to speak of, if it were to cause the chain price to be higher, but overall the Stihl chains work enough nicer from start to finish that they're worth a bit more.
Glen
