"Precut" chainsaw chain

[7sleeper]

Dear AS Community

Since I come from a different continent than most people here I would like to share a very(in my amature eyes) interesting discussion in an German Community called Landtreff (="rural meeting")http://www.landtreff.de/index.php.

The discussion here heated up because someone recommended a "precut" chainsaw chain.

Since no one else had experienced a "precut" chainsaw chain a lively debate about pros and cons developed (as would be expected on AS ).

All discusion was theoretical. The main argument against using a "precut" chainsaw chain was that the "precut" chainsaw chain would be much to jittery(=dangerous) in the cut since the depth gauge would not be doing its job right and the risk of kickback would be out of proportion. The main adversary arguement is that it would cut faster by "precutting" the wood fibers

Finally one member "treemaster" bought two brand new identicle chains and sharpened on one only the depth gauge with a 30 degree angle on a Stihl-USG sharpening device, the other chain was left untouched. As a testsaw he used a Stihl MS 260 and his test wood was a freshly cut fir tree.

This photo shows that he has not ground down the depth gauge but had left the original height intact.

The chains (top plate cutting edge) were not sharped as to keep the original factory edge intact.

His video (http://de.youtube.com/watch?v=P8SvAmaCrPY) is very impressing in putting the discussion to an end.
Standard quality:
<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/P8SvAmaCrPY&hl=de&fs=1"></param><param name="allowFullScreen" value="true"></param><embed src="http://www.youtube.com/v/P8SvAmaCrPY&hl=de&fs=1" type="application/x-shockwave-flash" allowfullscreen="true" width="425" height="344"></embed></object>

High quality: http://de.youtube.com/watch?v=P8SvAmaCrPY#

In the video german to english for the non native speakers means "VORSCHNEIDERKETTE = PRECUT CHAIN and STANDARDKETTE =
(what else ) STANDARD CHAIN and "TEST ABGEBROCHEN = TEST ABORTED he felt that further cutting would have been to dangerous.

After the test cutting he measured the largest wood chips thickness :
"precut" chainsaw chain chips were max. 0.9mm thick and the
"regular" chainsaw chain chips were max. 0.5mm thick

I believe that this is a very nice report on a theoretical idea.

Enjoy the video opcorn:

7sleeper from Austria

 

[blsnelling]

Very interesting. But why all the plunge cutting?

 

[Erick]

Stihl waiting for the rest of the video to load but so far it looks like a kickback machine, but once it was settled into the wood it did seem to cut faster than the standard chain. :dunno:

 

[Erick]

Finally got it all to load and play, looks like the "precut" chain was about 1 second faster for the three cut times, not even close to worth it for the kickback/injury potential of that chain.

Excellent video and test, thanks for posting it, I bet it put that whole argument to bed pretty quick.

 

[GASoline71]

Very interesting. But why all the plunge cutting?

I see the phenomenon has gone global...

Gary

 

[7sleeper]

Very interesting. But why all the plunge cutting?

The plunge cutting was an important criteria in the ongoing discusion. In Germany&Austria it is typical to use a much shorter bar than in the US. We have mainly 14 to 16 inch bars and 20 is long. It is often used for the standard large tree that has more diameter then the bar is long. The chain was supposed to be used in all forestry areas not only in bucking.
A typical feeling scenario includes cutting the wedge and then doing a plunge cut on the other side of the tree circumventing 1/4 of the tree then inserting the plastic wedges and completting the cut under constant force of the inserted plastic wedges.

I hope that was clear.

7sleeper

 

[7sleeper]

Finally got it all to load and play, looks like the "precut" chain was about 1 second faster for the three cut times, not even close to worth it for the kickback/injury potential of that chain.

Excellent video and test, thanks for posting it, I bet it put that whole argument to bed pretty quick.

There is a small link under the video for high quality if somebody is interested.

I believe it would be adequate to say it ended just then!
I hope the advocats don't feel .

7sleeper

 

[Philbert]

Interesting idea. Thanks for sharing your experiment with the forum.

In the U.S., we might describe the sharpened depth gauges as making a 'scoring' cut. Scoring cuts are used in furniture manufacturing to avoid damaging or tearing the finished surface or veneer. Not usually an issue in chainsaw work.

On a chain saw, this leading, sharpened edge cutting through the wood fibers would seem to do a less efficient job than the edge of the cutter designed to to this task.


"The main argument against using a "precut" chainsaw chain was that the "precut" chainsaw chain would be much to jittery(=dangerous) in the cut since the depth gauge would not be doing its job right"

This is very visible in your videos. But of course, this is a modified chain, not one designed for 'scoring' or 'pre-cutting'. By modifying the depth gauge you can't control how deep the cutter digs in. A chainsaw engineer might be able to design a cutter that does both.

You might get the same benefit of more cutting edges by using a chain with a smaller pitch?

Philbert

 

[testlight]

Ah the boring beetle has even made it over seas:jawdrop:





Oh.... wait, is that where it came from in the first pace??

 

[Blakesmaster]

I wasn't really surprised by this. It's like taking the rakers down a bit too far. As long as your saw has the azz it's a lot of fun till you try to bore.

 

[Tzed250]

I see the phenomenon has gone global...

Gary

Actually it came from that side of the pond...

 

[Tzed250]

The plunge cutting was an important criteria in the ongoing discusion. In Germany&Austria it is typical to use a much shorter bar than in the US. We have mainly 14 to 16 inch bars and 20 is long. It is often used for the standard large tree that has more diameter then the bar is long. The chain was supposed to be used in all forestry areas not only in bucking.
A typical feeling scenario includes cutting the wedge and then doing a plunge cut on the other side of the tree circumventing 1/4 of the tree then inserting the plastic wedges and completting the cut under constant force of the inserted plastic wedges.

I hope that was clear.

7sleeper

Notice the German 260 has a Quick Chain Adjuster...

 

[Zackman1801]

the saw sounds like a power drill, its weird. its a strange idea though, why would you need the rakers to cut the wood before the cutter gets there? its a really strange idea, i sometimes wonder how people think of things like this. although who knows maybe someone will find a way to make it work and it will become the norm. but another question, would the rakers/ depth guage be weakened by shaving off the side metal? what if you hit a rock could the depth guage be completely broken off due to making the guage thinner and have the chain be useless?

 

[Zackman1801]

Actually it came from that side of the pond...

yeah i think that soren erickson started it in the GOL stuff.

 

[clearance]

I can hardly believe it, WTF?

 

[Tzed250]

I can hardly believe it, WTF?

:agree2: :hmm3grin2orange:

 

[testlight]

So is that saw supposed to have an inertia chain break, cause:jawdrop: