Cutting Waterlogged Logs

[Daninvan]

Normally I slab up urban hardwoods. Recently I had the chance to go at a first growth Doug fir as well as an old spruce that was hundreds of yrs old and close to 32" in diameter. The Doug fir was a bit narrower, maybe 28" at the widest.

Both of these so-called softwoods were among the toughest logs that I have ever sawn. The amount of physical effort required to push the mill through them was tremendous. I had visions of Bobl giving me the ergonomics warning as I leaned over and into these to try and push the mill!

This was a puzzle for me, my mills cut very well in oak and elm and other sorts of temperate climate hardwoods. I am wondering if the fact that both these logs spent some time drifting in the ocean might have had something to do with it? The spruce log in particular was from an old boom, I have no idea how long it had been out there. I suppose it could be my chain as well, I sharpen mine to about 10 degrees or so. But I also have no problem with local cedars that drift ashore.

Looking for some thoughts on what could be causing this.

Cheers,

Dan

 

[losttheplot]

If the wood has been anywhere near a sandy beach your chain will dull after cutting less than an inch of wood.
Were you getting very fine dust ?

The sand gets into the bark even though you cant see it. The ends of the log also, because of the structure of wood.

If you suspect the wood is "sandy" you could try cutting a cookie from each end before you start milling.

Make your top cut and then if possible, drop right down and make the bottom cut.
Roll the log 90 degrees and put on a fresh chain.
That will give you clean edges to work with.

sawing a sandy beach log with a live edge is tough on man and machine.

The red cedar is so soft a dull chain will still get through it.
Dry Doug fir can be very hard. Especially if it has baked in the sun for a summer or two on the beach.

 

[mtngun]

Both of these so-called softwoods were among the toughest logs that I have ever sawn.

Now I don't feel so bad for my slow cut times with doug fir. It may be a softwood, but it is one of the stronger softwoods.

 

[Daninvan]

I don't think sand was an issue for a couple of reasons. Good guess though!

First, the log was dipped in the water first and then brushed it off just to be sure. Then I cut the ends off, to be honest I don't normally do that with most logs. I did so here because both these were way too long to fit in my van! Also, there was no bark so the surface was pretty smooth and easy to clean.

Second, I mill most of my logs at the same location on the beach, so if sand was dulling my chain it should do so on more of my logs, not just co-incidentally the only two softwoods I have cut.

I checked Malloff, who was cutting almost exclusively softwoods, and he says use 0 degrees for the cutter angle. I think the 10 degrees I am using is fine??

He also says to set the rakers at .045. I wonder if this is my problem, mine are only at .025 (sorry not using Bobl's angle system yet!), may not be sufficient for the softwoods? The mill was definitely not self feeding. My shavings were pretty dusty. But to my shame, they typically are in all the wood I cut!

Western red cedar has a Janka hardness of 580, versus 660 for Doug Fir and 510 for Sitka Spruce. So it appears that the Spruce is actually softer than the red cedar, I'm not sure why then a dull chain would cut the cedar but not the spruce?? Perhaps Janka is not a good measure of end grain hardness, which is effectively what we are cutting.

I had not considered the baking in the sun. I am sure both logs baked in the sun for a considerable time after being cut, especially the spruce. Yet they would not have dried out, as they were floating in the ocean. So I am a bit unclear as to how this effect would work? Perhaps they do dry in the ocean exposed to the sun, the bound water in the cell walls escapes but free water remains in the intercellular areas? Kind of the opposite of how wood normally dries? Seems plausible.

Dan, still puzzled in Van.

 

[woodenbiker]

One other thought may be the fact that the were water logged with salt water as apossed to fresh water. I am sure that salt and other minerals although disolved in the water could be quite abrasive.
Not sure there is a solution to that other than a carbide chain.

Just a guess and my 2 cents for what its worth.

 

[DRB]

I would say that sand is you biggest enemy. If thous logs have ever touched the beach there will be sand and rocks embedded into the wood. I am lucky to get two cuts on a 10 foot log before touching up the chain. The chain usually does not look that bad but but a quick touch up picks up the speed again. I try to get the outside off the log in as few cuts as possible. Don't roll your nice clean cant in the sand. Now you have a nice clean cant to start ripping off boards. I cut all my logs into edged lumber now so I don't have to cut through sandy live edged boards. Table saws and planers don't like the sandy live edges ether. Also makes for easier stacking of the boards and you can leave more of the messy saw dust and edgings behind instead of bringing it home with you.

I can usually get some extra boards from the thick slabs I get off the cant. Use your guide board to draw a line and the edge off the both live edges free hand. This way you will get a couple more boards cut with out cutting the sandy live edge.

You can't always see the sand but I am sure its there. In a crack or rough spots on the log. Unless the logs never touched the beach even at the booming ground when the tide goes out?

 

[BobL]

I don't think sand was an issue for a couple of reasons. Good guess though!

First, the log was dipped in the water first and then brushed it off just to be sure. Then I cut the ends off, to be honest I don't normally do that with most logs. I did so here because both these were way too long to fit in my van! Also, there was no bark so the surface was pretty smooth and easy to clean.

Second, I mill most of my logs at the same location on the beach, so if sand was dulling my chain it should do so on more of my logs, not just co-incidentally the only two softwoods I have cut.

Yep, I agree

I checked Malloff, who was cutting almost exclusively softwoods, and he says use 0 degrees for the cutter angle. I think the 10 degrees I am using is fine??

Top plate filing angles are not going to affect the cutting speed that much

He also says to set the rakers at .045. I wonder if this is my problem, mine are only at .025 (sorry not using Bobl's angle system yet!), may not be sufficient for the softwoods? The mill was definitely not self feeding. My shavings were pretty dusty. But to my shame, they typically are in all the wood I cut!

In your softwoods you should be generating bit fat wood chips.
Old timers like my dad didn't mess around with angles and gauges etc, they just used to just keep taking their rakers down till the got chips If you don't want to mess with angles etc just get yourself a filoplate.

Western red cedar has a Janka hardness of 580, versus 660 for Doug Fir and 510 for Sitka Spruce. So it appears that the Spruce is actually softer than the red cedar, I'm not sure why then a dull chain would cut the cedar but not the spruce?? Perhaps Janka is not a good measure of end grain hardness, which is effectively what we are cutting.

I had not considered the baking in the sun. I am sure both logs baked in the sun for a considerable time after being cut, especially the spruce. Yet they would not have dried out, as they were floating in the ocean. So I am a bit unclear as to how this effect would work? Perhaps they do dry in the ocean exposed to the sun, the bound water in the cell walls escapes but free water remains in the intercellular areas? Kind of the opposite of how wood normally dries? Seems plausible.

If the salts content in the ocean is greater than that inside wood cells, this will draw water out of wood cells and make them shrink which will be the same as drying out. So the log may be very wet but has actually shrunk and hardened.

 

[losttheplot]

If the ends you cut off the Fir/Spruce logs are still available, try making some cuts. If it is still really hard to cut try cutting a peace of wood you know is relatively easy to cut, using the same chain (dont touch it with a file).
If it cuts as it should you know it is the hardness/density of the drift wood slowing you down. If it does not cut as it should try sharpening the chain and cutting the known (control) log again.
A process of elimination.

I use one of the Husky progressive gauges for the rakers. If I cut fresh Doug Fir down hill my saw will almost self feed. I used to use .25 but I found it is not the best in "soft" woods. I find fresh cut Fir is significantly faster to cut than well seasoned wood.


The logs that you cut I dont know, from what I see around here, the wood comes ashore maybe hangs around for a while then moves off to another beach to hang out for a while. Sometimes the bigger pieces stay in one place for a year or three then move on. The winter storms move things around more so than in the summer.

In the summer the wood on the beach gets very dry. The tides are low most times in the day during the summer, they may not get wet between the big spring tides. They become so dry that they crack along their length. The cracks are wide enough to let the sand get in. They can be several inches deep and wide enough to fit a dollar coin edge into. The wind blows the sand into the cracks, also the waves stir up the sand and washes it into the cracks.

This time of year the rain water soaks the wood, the tide is in most of the day and the sun does not shine quite as often ;-) This causes the cracks to close up, leaving the log looking smooth and trapping the sand in the wood. The sand can be several inches into the wood, you cant see it and you certainly cant wash/brush it off.

The wood with bark on it does not suffer this problem as much.

I hate to assume, but from what i gather the urban hardwoods you cut are dumped in their present location, where as the drift wood may not have always been on that particular beach.
How long had the wood been in the ocean, on and off the beach who knows..... months, years.......... decades........

I may well be mistaken, but I think the Fir gets significantly harder as it dries. I dont know if this is also the case for spruce or Cedar.
Perhaps Mr Janka could tell us ?



I am not arguing or doubting what you say, all that I have said was typed with all due respect.
I hope you find the answer as I think there are a few people that would like to know ;-)

 

[DRB]

If the ends you cut off the Fir/Spruce logs are still available, try making some cuts. If it is still really hard to cut try cutting a peace of wood you know is relatively easy to cut, using the same chain (dont touch it with a file).
If it cuts as it should you know it is the hardness/density of the drift wood slowing you down. If it does not cut as it should try sharpening the chain and cutting the known (control) log again.
A process of elimination.

I use one of the Husky progressive gauges for the rakers. If I cut fresh Doug Fir down hill my saw will almost self feed. I used to use .25 but I found it is not the best in "soft" woods. I find fresh cut Fir is significantly faster to cut than well seasoned wood.


The logs that you cut I dont know, from what I see around here, the wood comes ashore maybe hangs around for a while then moves off to another beach to hang out for a while. Sometimes the bigger pieces stay in one place for a year or three then move on. The winter storms move things around more so than in the summer.

In the summer the wood on the beach gets very dry. The tides are low most times in the day during the summer, they may not get wet between the big spring tides. They become so dry that they crack along their length. The cracks are wide enough to let the sand get in. They can be several inches deep and wide enough to fit a dollar coin edge into. The wind blows the sand into the cracks, also the waves stir up the sand and washes it into the cracks.

This time of year the rain water soaks the wood, the tide is in most of the day and the sun does not shine quite as often ;-) This causes the cracks to close up, leaving the log looking smooth and trapping the sand in the wood. The sand can be several inches into the wood, you cant see it and you certainly cant wash/brush it off.

The wood with bark on it does not suffer this problem as much.

I hate to assume, but from what i gather the urban hardwoods you cut are dumped in their present location, where as the drift wood may not have always been on that particular beach.
How long had the wood been in the ocean, on and off the beach who knows..... months, years.......... decades........

I may well be mistaken, but I think the Fir gets significantly harder as it dries. I dont know if this is also the case for spruce or Cedar.
Perhaps Mr Janka could tell us ?



I am not arguing or doubting what you say, all that I have said was typed with all due respect.
I hope you find the answer as I think there are a few people that would like to know ;-)

+1 :agree2:

Very good description of drift wood life cycle.