Algorithm for maximum diameter for a given bar length

[HelpfulHatchet]

I have an 18" 2-cycle gas Craftsman saw. I volunteer in town helping folks too poor or too old to take care of downed trees on their home's property. I spoke with a disabled senior yesterday who said he thought the tree that blew over this week was close to 30" in diameter. I'm going to see if he can send a cellphone photo of it but it got me to thinking about what the maximum diameter I should attempt with my 18". I'm aware that > 18" can be done safely with proper technique (sources for these would be warmly received!) but which should I immediately seek a professoinal for?

I only work on fallen trees that do not pose a hazard for myself or the surrounding area. As an amateur I know my limits are tight and have no problem seeking help for projects that are beyond my skillset.

Thanks for reading!

 

[Trdoldtreecutter]

In a big old growth a guy can bore out some of the heartwood if he makes a wide undercut to accommodate his motor. Probably limited to double the bar length with a 30” tree without doing some really weird stuff. My personal best in a sound tree was 6’ 9” inside the bark with a 36 on pretty flat ground up in the Gifford Pinchot. It school marmed up about 80 feet and didn’t have any noticeable taper so the first bucking cut wasn’t complete

 

[Trdoldtreecutter]

Oops, thought you meant how big you could cut down

 

[HelpfulHatchet]

Oops, thought you meant how big you could cut down

Yes. This one is on the ground already but love the tale nonetheless!

 

[Trdoldtreecutter]

In a case like that it might be possible to get say 8-10 ft lengths as close cut up as possible and then break apart with a winch or come along and then roll to complete, it’s common to cripple logs on steep ground to avoid being killed, just leave a post on the inside that doesn’t cause to much damage

 

[sundance]

Without doing exotic things, the easy answer is the shy side of twice your working bar length (which may be less than twice advertised length). That said, a 42 cc saw isn't a good match for a 30" + tree.

 

[HelpfulHatchet]

Without doing exotic things, the easy answer is the shy side of twice your working bar length (which may be less than twice advertised length). That said, a 42 cc saw isn't a good match for a 30" + tree.

Is that decause it doesnt have the power to make it through without overheating?

 

[sundance]

Is that decause it doesnt have the power to make it through without overheating?

I think it could be done but it would be a slow and painful effort. Since a log would imply several such cuts i'd suspect you could kill the saw working through them.

 

[lone wolf]

I think it could be done but it would be a slow and painful effort. Since a log would imply several such cuts i'd suspect you could kill the saw working through them.

Especially with a dull chain and heavy hand.

 

[Trdoldtreecutter]

It would make an interesting video though so wth

 

[Trdoldtreecutter]

Be careful cutting the log away from the root ball. And if it stays up after you cut it loose prop some boards behind it so it don’t flop down and squish someone

 

[ElevatorGuy]

If those 30” are hardwoods you’re gonna kill the craftsman. That’s not a bad thing, Time for a nice saw!

 

[TheTreeSpyder]

Just because bar is long enough doesn't mean power head can adequately drive it thru, especially all day, especially to real 3/8 wide kerf.
A pro saw is made for all day at heavy duty, home owner saw not so much.
Especially in denser species and or dry dead, also cut if not squarely across grain can bog work.
Would look to butter bar a lot and open oiler wide if can.
>> would not keep saw buried long periods but rather bring out to breathe and oil freely occasionally.
Start with sharp chain and plot not to come close to ground.
>> 1 grain of sand averages 18 cutting edges of uncrushable silicate , powered by saw
>> can 'sandblast' tooth from cutting as sharp knife to about trying to cut with back of spoon!
.
Top bind pressure can be immense here size and weight wise
>> face into compression as tension holds face open, then back cut from tension side.
>>reduce settling if can and divert top/top @ high noon peak pressure close/pinch to top/side instead to soften pinch/bind

 

[tfp]

Make sure you have some wedges, especially if you don’t have another saw to cut your saw out if you make a boo boo

 

[HelpfulHatchet]

Make sure you have some wedges, especially if you don’t have another saw to cut your saw out if you make a boo boo

I have 1 wedge but if it is actually 30 inches in diameter I cant burn up my saw on that. Any places where I could keep an eye out for a used pro saw?

 

[HelpfulHatchet]

I think it could be done but it would be a slow and painful effort. Since a log would imply several such cuts i'd suspect you could kill the saw working through them.

By "kill the saw" do you mean permanently?

 

[sundance]

By "kill the saw" do you mean permanently?

Permanently....or significant repair cost.

 

[ElevatorGuy]

By "kill the saw" do you mean permanently?

Yes, Craftsman saws are junk. I killed my old mans craftsman in a large red oak. That was the nicest saw he ever bought. Lesson learned, my first saw was a stihl.

 

[Trdoldtreecutter]

I’ve seen quite a few decent used saws on Craigslist but it might be because of the area I’m in

 

[Bobby Kirbos]

If it's a newer Craftsman saw... yeah, that's a home owner class machine and you're going to put some serious miles on it working that big wood. I did a 30" + diameter oak tree, 15 years ago, with a big box store Poulan. Did it get the job done, yes. However, the box store saws are not pro grade, and they have only gotten worse.

However, the Echo stuff IS pro grade (at least semi-pro) and can be found at Home Depot. If you have the coin to swing a new saw, and you can only afford 1 saw, look at an Echo 590. A 20" bar would get you through just about anything you may run into.