Sprocket/chain sizes

[cgarman]

So I got into CS milling last year, and now I'm hooked. My setup has evolved to the point where I need a new baseline. I bought the 56" GB mill, and hooked it up to my 42cc Poulan converted to .375 sprocket. That was funny. It barely turned the chain out of the cut, so I gave up pretty quick. I should have take a picture, because the bar weighed more than the saw.

My buddy bought a Dolmar 7900 which I borrowed for a while to run on my .375 chain setup. I worked well, but it wasn't long until I bought my own Stihl 076. Because I already had the B/C I converted the 076 down to .375 (sprocket is cheaper than chain.)

Since the saw shop ruined my chain last year, it's about time for a new one. I still have the .404 sprocket. Is it worth going up to .404 chain? Basically, I have all the parts to go either way, so there is no cost beyond the new chain. Both chain sizes are the same price.

I'm cutting 90% red oak in widths from 18" to 48". Most is around 24". I also need to mill a cherry and maple, similar size. Will I get a faster cut with .404"? Anybody done a test to see? On one hand, it seems like each cutter will remove more wood. But then again, there are fewer cutters in the wood at a time. Does it all equal out? I guess if nothing else, I have fewer teeth to sharpen....

 

[mtngun]

Is it worth going up to .404 chain? Will I get a faster cut with .404"? Anybody done a test to see?

You want to run the narrowest chain that is compatible with your powerhead. Forget about 404.

For example, 3/8 lo-pro is about 25% faster than regular 3/8.

325 may be up to 17% faster than 3/8, according to an old thread by Aggiewoodbutcher.

For your 076, you should probably stick with 3/8.

 

[cgarman]

You want to run the narrowest chain that is compatible with your powerhead. Forget about 404.

OK - I get that a smaller kerf means less work for the saw (from my table saw experience) however the .404 and .375 measurements apply to the length of the drive link, not the width of the cutter. Is the cutter on a .404 chain wider than one on .375? Is this what's meant by low-pro .375? The kerf is narrower, but the length is the same as regular .375?

Any special requirements to run low-pro ripping chain? Does it come in standard gauges? Should I just stick with my standard .375?

I know that's a lot of questions, but I'm in a place where I can start over with my chain/sprocket combo (need to replace both) and want to make the right choice.

 

[mtngun]

3/8 has a narrower kerf than 404, 325 is narrower than 3/8, lo-pro is narrower than 325.

But ...... there is a limit to how much horsepower, and how much bar length each chain can handle.

Yes, lo-pro requires special sprockets at both ends. An 076 has too much grunt for lo-pro.

For your 076, 3/8 is probably the best choice. 325 would be slightly faster, but it's a hassle to round up the special sprockets, more so in the case of the 076 rim.

 

[cgarman]

OK - makes sense to stay with what I have then. Thanks for confirming.

Next question. I plan to occasionally take the 076 off the mill to cut some large logs for firewood or to mill. I don't have a bar for the saw, except the 56" double ender. If I plan to buy a 36" or 42", should I also stick with .375 for cross cuts? It would make it easier to switch out if I don't have to change the sprocket.

 

[mtngun]

should I also stick with .375 for cross cuts?

I would.

 

[john taliaferro]

I would.

I would , you get time take a camera cutting with you we like pictures. :msp_biggrin: