Chainsawing wet logs

The water levels have been below winter norms on my local Patuxent, pushing me a little downriver of where I wanted to paddle. Just to the north of Rt. 50, about a mile above the launch at Gov. Bridge, there have been two river-spanning logs, about 20" diameter. They are trunks from the same root ball. I thought they might be out of the water and that I’d take advantage to notch’ em.

I know. I know. River ecology and all. But I think these particular logs were not of particualr benefit to bank stabilization or nesting wildlife.

On Saturday, the upriver member of the twin span was almost completely out of the water. My Stihl, woodboss .028 does not saw well in wet logs. The wood clogs the chain and oiling devices and the sprocket at the end of the bar quickly freezes so that I have to disassemble and clean it all. My chainsaw guy says I should expect that to happen when sawing wet logs, and at regular intervals I should take time out from cutting to run the saw and let it unclog itself. I forgot to do it on Saturday, and the saw froze with about 4" of the first cut still to go. I finished the cut by hand.

I went back on Sunday and tackled the second log, which was mostly submerged. My saw cuts very poorly with the bar in the water. Clogging was not an issue, but it just didn’t seem to have any power and I only was able to apply a bit of pressure at a time, then let it build up rpm. I made steady, but very slow progress. I was working at cutting a vertical V on the downstream side, through about half the diameter, and almost got it cut before I ran out of fuel (only brought what was in the saw).

The V? One thing I learned about cutting logs in the river is that it is very difficult to predict the forces acting on the tree, and that avoiding a binding situation is always a challenge. So I start with a big V. More cutting but reduces the binding surface and usually works out better.

I have two questions for the board.

1.) Anybody know why the saw doesn’t function well with the bar in the water?

2.) Anybody have any experience with the hand-operated cutting chains and care to predict how useful they might be for cutting an underwater log?

This log is a little too wide for any of my hand saws.


not exactly to your question, but…
When I have to cut wet logs like after a hurricane, if the log is not saturated, take a hatchet and girdle the log just about a coupla inches wide and deep enough to get below the wet bark and wood. Often logs are not very wet just below the bark. This will reveal a dry area to chainsaw through. I’m not sure how deep the path would have to be for logs soaking in water for a long time, but greener logs stay pretty dry just below the bark. I agree chainsaws in water and on wet wood do not function well. I agree they are nasty devices but sometimes necessary. Good luck

Have similar experiences, however I have found that bigger chainsaws cut wet logs better and the ones with automatic oilers work better. The problem I had with my commercial grade Husky was the saw would sling water all over me.

I almost hate to recommend
a chain with carbide teeth (they are vicious cutters, including rocks and steel-toe boors) but they go through wet and even frozen wood quite well.


adjust cutters
try sharpening your cutters more straight across, at less of an angle, or more perpendiclar to the bar. File down the rakes a little more.

I’ve got a Stihl MS310
& it works just fine cutting wet, water-logged & submerged logs. It’s a larger model w/ auto oiler which as swedge suggested may help (flinging water can be solved by using top of bar to make cut - sending water away from you)

I haven’t cut out blowdown in freezing temps thus have no experience in those conditions. I use a plunge cut into the top of an otherwise submeged log to minimize splash. Also, only cut out a canoe-wide channel thru any log that totally spans waterway (but re-arranging by Spring flooding can require re-doing the job

It’s just more resistance
when the bar is submerged.

Even when cutting dry trees, there just isn’t a lot of resistance to the chain anywhere except the one or two teeth that happen to be taking a small bite at the tree. As soon as you submerge the bar, water is providing resistance everywhere along the chain.

You just need more power and to limit as much as possible the submerged part of the bar. Or if the water is up, wait for it to go down before cutting.

There are numerous dangers in cutting submerged logs, so for those who read this – don’t try this at home. Leave it to the pro’s.


Veg Oil

– Last Updated: Jan-05-09 2:42 PM EST –

The County work crew that clears tree blockages(some submerged)from two local creeks from a boat use vegitable oil for chain lube. I don't know if it is for pollution issues or performance or both,but they seem to cut well.When I have done this it seemed the water was washing the lubrication off the bar.They also cut all trees in firewood length(16")pieces so they don't just create another block down stream.Locals also like this as they harvest the pieces they can get for firewood! I havn't tried veg oil, but I plan on it and also some of the ideas here. Sprayed water and sawdust are really a pain!

biodegradeable oil…
I help with some chainsaw work on our rivers from time to time, and our guys really like this stuff:

Seems to be much better if you are working in/around water…you can visibly see a difference. Here (in Arkansas) often it has to be special ordered, but it seems worth it.

Just for anyone interested, we try to keep these general guidelines in minds from AW. We still clear log jams when there is going to be a real safety issue, but we do try to keep this info in mind…

“Strainers, Large Woody Debris, Removal, and Ecology”

It provides a very good discussion on things to think about to keep your impacts on the local ecology within reasonable bounds.

Happy Chainsawing…

Stihl BioPlus
is what we use in all of our chainsaws at work. Very thick canola oil, I believe. We used to have to special order, but now the local Stihl dealer has a shelf full of it. It is more expensive, but I feel less guilty, especaially when cutting in water.

For dealing with un-expected forces on horizontal logs, my favorite cut is what I call a “top lock”. (I don’t think loggers call it that.) Make two (or three) cuts about 5" apart and perpendicular to the trunk. Make them a couple inches deep depending on the diameter of the tree. But quit well before you expect it to pinch. Now come in from the opposite side between the two cuts. Again, don’t go to the pinch point. Now you will be able to see where the tension is by which cuts close up. If necessary you can make a lot of cuts and on both sides and relase the tension slowly with out the trunk exloding. When you feel safe, come in from the cut that is getting wider. and once you pass the two cuts from the opposited side the the log will release safely. If you notice more tension up/down (where you expected side/side tension) you can make new cuts there. Etc., etc. It is a relatively safe cut in many situations.

hey Chip , large couse cut teeth …
… and 5 gal. bucket w/90 weight gear oil .

Small tooth chain is for limbing .

Keep dipping bar into bucket , pulsed rev-ups and clear .

Keep those teeth sharp .

mail coming …

Thanks p-netters
Thanks for all the interesting and useful replies. A day removed from the “heat of battle,” I think I am just going to let the log be.

Seems to me, my chainsaw doesn’t like cutting in the river. I started it yesterday to let it get hot and cook off any water that might be lingering, and noticed the automatic oiler was failing to get oil to the bar (it was drooling out the sawdust chute). Took off the bar and cleaned out all the ooze that had plugged the bar. As Richard wrote, you may not need oil at all if you keep the bar wet, but using oil was ineffective with the bar all clogged.

Then there is the difficulty of cutting that particular log. The river has sculpt out beneath that log to 10’. So there is no footing. Half will want to float. The root ball half will maybe want to fall. Pressure from the current will want to push things downriver. Maybe I’ll go back with the Riverkeeper’s team next season, or maybe it will just stay a carry-over log in the stream, but I think it is more than I want to tackle on my own, unless I happen into a single-man timber saw.

Useful to know that Stihl has an eco-friendly oil. I’ll look for that next time I see my Stihl man.

Useful technique described on how to cut when the timber is under pressure. I’m sure I’ll use that at some point.

Thanks for all the info.


hand saws
I have tried hand powered saws because of difficulties with a chainsaw under water. They cut OK,but the big problen is that where I have to cut you can rarely find a place to brace yourself for the push and pull strokes.I’m usually either in a boat or perched on the jam itself.


The right household chemicals…
mixed in the right proportions you can make some decent explosives. Then, you need to figure out the fuse timing. You’ll want to get far enough away.

to detonate explosives in a stream.
thats a sick joke. right?

Just kidding
I would never advocate using explosives.

i figgered as much
i also realize this is a very public forum. lotsa nutsos including me!

seems like in the right proportion, explosives would be an ideal solution to rending logs that are otherwise difficult to get at/on. Just enough boom to blast a gap in a two or three foot thick log, no need to nuke the riverbed.

It’s not the first time the thought has occurred to me and I actually spent some time looking into the permitting process to be able to legally use explosives. Didn’t seem too daunting, but more than I’d care to undertake on a casual basis. Then there are issues about proper magazine storage facilty and so forth…way too much trouble. Just carry around the damn logs.

Somebody once posted a hilarious, and true-sounding, account of a relatives experience trying to relocate beavers, using not the carrot but the stick–of dynamite. I’d love to reread that if somebody could dredge it up.

As a kid, I was a pyrotecnomaniac. I used to build functional model boats, rockets and planes and would incorporate firecrackers, cherry bombs, or what-ever into the models as I was building them. Most only got a test flight or two before I’d blow them up. And I got good at cutting open firecrackers to reuse the powder in my own, bigger explosives. So, ya, the thought of boring a hole into a log and packing it with an appropriate amount of explosive has occurred to me.

However, while having enormous appeal to me, it’s not a practical idea. Even I know that much.


people sure love to see them go off …
… in the movies and such though , don’t they ??

Hollywood has become the “explosion” psycho of them all … something wrong about all that , I think … but I guess violence is a big seller .

You got it.
The Wiley E Coyote challenge:

“you can rarely find a place to brace yourself for the push and pull strokes.I’m usually either in a boat or perched on the jam itself.”

That’s one reason I was asking about the hand-op saw chains. Made for throwing over a branch and cutting from many feet away, seems like they could do the job. But the ones I’ve seen aren’t long enough to tackle anything of significant diameter.

Pole saws can do a decent job. But again, limited to smaller logs.

Anchoring upstream, an arms length from the log can help.

But, ya, challenging.