Why does green wood dull tools faster than dry wood?

Why does green wood dull tools faster than dry wood?

Post by Greg Lyma » Thu, 04 Oct 2007 12:22:00



Anyone have opinions about why green wood dulls gouges (M2, M4, and Kryo M2)
and band saw blades so fast relative to the same wood dry?  One would think
that the water would cool and lubricate the cut versus dry wood, but still
it appears as if tools dull much faster.  I work mostly with English Walnut,
"Black" Walnut root burl and Western Maple.  Perhaps having a scary-sharp
edge is just more critical to sever the wet fibers...I don't know.  Do you?

This group has never been short of people with opinions (albeit some more
reasoned than others) so I thought I'd ask to see if anyone has a reasonable
explanation.

 
 
 

Why does green wood dull tools faster than dry wood?

Post by nailshoote.. » Thu, 04 Oct 2007 14:29:58


My experience has been the resin buildup on the tools.  When I have
turned really green or wet woods, the heat seems to dry out (cook?)
the resin from the sap onto the tools.  Just like a saw blade, a resin
encrusted cutting tool is its own worst enemy because as the resin
builds, it generates more heat.  As the heat rises it cooks more resin
onto the cutting edge.

I always keep a large cup of water next to the grinder, and when I
turn really wet woods I dip the tool into water and wipe before
getting resin into/onto my grinding wheels.

Robert

 
 
 

Why does green wood dull tools faster than dry wood?

Post by Greg Lyma » Thu, 04 Oct 2007 17:17:35


Resin is not a problem with the woods I am turning.  There is clearly
something more to it, but I'm not sure what it is.


Quote:
> My experience has been the resin buildup on the tools.  When I have
> turned really green or wet woods, the heat seems to dry out (cook?)
> the resin from the sap onto the tools.  Just like a saw blade, a resin
> encrusted cutting tool is its own worst enemy because as the resin
> builds, it generates more heat.  As the heat rises it cooks more resin
> onto the cutting edge.

> I always keep a large cup of water next to the grinder, and when I
> turn really wet woods I dip the tool into water and wipe before
> getting resin into/onto my grinding wheels.

> Robert

 
 
 

Why does green wood dull tools faster than dry wood?

Post by Georg » Thu, 04 Oct 2007 18:40:57



Quote:
> Resin is not a problem with the woods I am turning.  There is clearly
> something more to it, but I'm not sure what it is.

How about corrosion?  Especially with acid woods.
 
 
 

Why does green wood dull tools faster than dry wood?

Post by Darrell Feltmat » Thu, 04 Oct 2007 19:50:28


Greg
In my experience green woods do not dull the edge faster than dry ones with
a couple of notable exceptions. (I am turning mostly woods domestic to Nova
Scotia) Cedar and juniper family trees will have sap that will dull a blade
faster than even hard maple. The sawyers here use special mills to cut dedar
boards, special because they do not mind sharpening saws. The other
exception comes from most of the green wood I turn still having the bark on
and it often has abrasive dust from the felling and sometimes from the
environment. Once the bark has been removed the edges last longer.

--
God bless and safe turning
Darrell Feltmate
Truro, NS Canada
http://aroundthewoods.com
http://roundopinions.blogspot.com


Quote:
> Anyone have opinions about why green wood dulls gouges (M2, M4, and Kryo
> M2) and band saw blades so fast relative to the same wood dry?  One would
> think that the water would cool and lubricate the cut versus dry wood, but
> still it appears as if tools dull much faster.  I work mostly with English
> Walnut, "Black" Walnut root burl and Western Maple.  Perhaps having a
> scary-sharp edge is just more critical to sever the wet fibers...I don't
> know.  Do you?

> This group has never been short of people with opinions (albeit some more
> reasoned than others) so I thought I'd ask to see if anyone has a
> reasonable explanation.

 
 
 

Why does green wood dull tools faster than dry wood?

Post by Kip » Thu, 04 Oct 2007 22:34:46



Quote:
> Resin is not a problem with the woods I am turning.  There is clearly
> something more to it, but I'm not sure what it is.



> > My experience has been the resin buildup on the tools.  When I have
> > turned really green or wet woods, the heat seems to dry out (cook?)

> > Robert- Hide quoted text -

> - Show quoted text -

I agree with  Darrell-there is abrasive material in the bark.  When
the bark is cut away, I resharpen and find that with the woods I
usually work (various Ozark region hardwoods), edge life is longer
than for dry wood in the sam species.  And the shavings hittin my hand
are a lot cooler!

Kip Powers
Rogers, AR

 
 
 

Why does green wood dull tools faster than dry wood?

Post by Michael O'Connel » Thu, 04 Oct 2007 23:48:08



Quote:
> Anyone have opinions about why green wood dulls gouges (M2, M4, and Kryo
> M2) and band saw blades so fast relative to the same wood dry?  One would
> think that the water would cool and lubricate the cut versus dry wood, but
> still it appears as if tools dull much faster.  I work mostly with English
> Walnut, "Black" Walnut root burl and Western Maple.  Perhaps having a
> scary-sharp edge is just more critical to sever the wet fibers...I don't
> know.  Do you?

> This group has never been short of people with opinions (albeit some more
> reasoned than others) so I thought I'd ask to see if anyone has a
> reasonable explanation.

 
 
 

Why does green wood dull tools faster than dry wood?

Post by mac davi » Thu, 04 Oct 2007 23:59:31


Quote:

>Anyone have opinions about why green wood dulls gouges (M2, M4, and Kryo M2)
>and band saw blades so fast relative to the same wood dry?  One would think
>that the water would cool and lubricate the cut versus dry wood, but still
>it appears as if tools dull much faster.  I work mostly with English Walnut,
>"Black" Walnut root burl and Western Maple.  Perhaps having a scary-sharp
>edge is just more critical to sever the wet fibers...I don't know.  Do you?

>This group has never been short of people with opinions (albeit some more
>reasoned than others) so I thought I'd ask to see if anyone has a reasonable
>explanation.

What kind of green wood are you turning?

Bark on or off?

In my experience, most green woods are easier on the tool edge than dry wood..

As to the bark, it would seem that if there IS a difference, wet would be easier
on the tool if there is sand, etc. in the bark, as it wouldn't be as "set" in
the bark?

My first 2 tools when turning green wood with bark on are the stud finder and a
2" roughing gouge..

You sort of want to avoid nails, barbed wire and assorted stuff that is often in
branch or trunk wood... It's a "no drama, no trauma" kind of thing.....

A few years ago, I bought the Benjamin's best 3 piece bowl gouge set from PSI
and it came with a 2" gouge that looks like a huge dog food scoop...
About the only thing I use the monster for is taking bark off stuff because it's
big, heavy and ugly and I don't care if I hurt it..

mac

Please remove splinters before emailing

 
 
 

Why does green wood dull tools faster than dry wood?

Post by robo hipp » Fri, 05 Oct 2007 01:29:22


I have never noticed that wet wood dulls tools faster than dry wood. I
turn green wood almost exclusivly, but notice a big difference in
dulling turning tools when I do the occasional dry piece. When cutting
green wood on the bandsaw, I think green wood cuts with less
resistance, as long as you have a sharp blade with the proper tooth
set and gap. Dry wood cuts more slowly, but will cut better with a
different tooth set than my usual resawing blades.

The biggest difference in dulling seems to be the woods. The prettiest
myrtle wood comes from the Oregon and north California coast. It can
dull the tools more quickly than other woods. My theory on that is
that it has a higher silica content than most other woods because
growing on the coast, it sucks up a lot of micro particles of silica/
sand.

I have noticed that the walnuts (English, Black, and Butternut) seem
to dull the tools rather quickly for woods that aren't that dense. I
have suspected that since they are acidic in nature, that the acid
could be the culprit, like George said. I suppose Oak will do the same
thing, but I almost never turn oak.

Density of the wood does contribute, and I haven't realy noticed that
bark contributes, if it is clean. If it has been laying on the ground,
then it picks up grit.

With the different grades of steel, I have noticed little difference
in the time that any steel will hold the 'fresh off the grinder' edge.
The harder steels will hold the 'I can still hog off a lot more
material' edge than the M2 does.

All of this is theoretical, just observations that I have made.

robo hippy


Quote:

> >Anyone have opinions about why green wood dulls gouges (M2, M4, and Kryo M2)
> >and band saw blades so fast relative to the same wood dry?  One would think
> >that the water would cool and lubricate the cut versus dry wood, but still
> >it appears as if tools dull much faster.  I work mostly with English Walnut,
> >"Black" Walnut root burl and Western Maple.  Perhaps having a scary-sharp
> >edge is just more critical to sever the wet fibers...I don't know.  Do you?

> >This group has never been short of people with opinions (albeit some more
> >reasoned than others) so I thought I'd ask to see if anyone has a reasonable
> >explanation.

> What kind of green wood are you turning?

> Bark on or off?

> In my experience, most green woods are easier on the tool edge than dry wood..

> As to the bark, it would seem that if there IS a difference, wet would be easier
> on the tool if there is sand, etc. in the bark, as it wouldn't be as "set" in
> the bark?

> My first 2 tools when turning green wood with bark on are the stud finder and a
> 2" roughing gouge..

> You sort of want to avoid nails, barbed wire and assorted stuff that is often in
> branch or trunk wood... It's a "no drama, no trauma" kind of thing.....

> A few years ago, I bought the Benjamin's best 3 piece bowl gouge set from PSI
> and it came with a 2" gouge that looks like a huge dog food scoop...
> About the only thing I use the monster for is taking bark off stuff because it's
> big, heavy and ugly and I don't care if I hurt it..

> mac

> Please remove splinters before emailing

 
 
 

Why does green wood dull tools faster than dry wood?

Post by Georg » Fri, 05 Oct 2007 05:34:42



Quote:
> The biggest difference in dulling seems to be the woods. The prettiest
> myrtle wood comes from the Oregon and north California coast. It can
> dull the tools more quickly than other woods. My theory on that is
> that it has a higher silica content than most other woods because
> growing on the coast, it sucks up a lot of micro particles of silica/
> sand.

Seems unlikely the tree could transport particulates, though soluble silica
compounds may be metabolized into less soluble or insoluble types.  One
common mineral stain in our local woods is calcium oxalate, the stuff of the
common kidney stone.  It will dull tools, that's for sure.

I'm sure others have noticed that trees which retain branches for a long
time often have greenish stain in the convoluted grain on the ground side of
the branches, where a less-soluble compound would naturally slow along with
the reduced flow to the crown.  I rather suspect this is the same calcium
oxalate.  Our common eastern white cedar is one which has both green and the
dulling effect.  Proportionate, I don't know.  Never paid that much
attention.  I sharpen when the tool is no longer cutting cleanly.

 
 
 

Why does green wood dull tools faster than dry wood?

Post by mac davi » Sat, 06 Oct 2007 01:10:05


<snip>

Quote:

>The biggest difference in dulling seems to be the woods. The prettiest
>myrtle wood comes from the Oregon and north California coast. It can
>dull the tools more quickly than other woods. My theory on that is
>that it has a higher silica content than most other woods because
>growing on the coast, it sucks up a lot of micro particles of silica/
>sand.

<snip>
>robo hippy

Funny that you should mention that, Reed... A friend that lives in Alaska
stopped on the Oregon coast on his way here and brought me a bag of myrtle wood
pen blanks..
I'm looking forward to playing with them, they sure are pretty wood..

mac

Please remove splinters before emailing

 
 
 

Why does green wood dull tools faster than dry wood?

Post by Mark Fitzsimmon » Sun, 07 Oct 2007 04:10:59



Quote:
> Anyone have opinions about why green wood dulls gouges (M2, M4, and Kryo M2)
> and band saw blades so fast relative to the same wood dry?  

I turn a lot of walnut and maple and find the exact opposite: dry wood
always dulls tools faster, unless the bark is still on, and then I
suppose it's dirt in the bark.
Band saw blades are another matter, but the only time I have fast
dulling problems with bandsaws is with sapwood, and I'm not sure it's
dulling so much as clogging up the blade with sap. Maybe try cleaning
the tool edge when you think they're dulling quickly and see if it's
not just a tiny bit of buildup at the edge?
 
 
 

Why does green wood dull tools faster than dry wood?

Post by turnerbo » Mon, 08 Oct 2007 06:38:46



Quote:
> Anyone have opinions about why green wood dulls gouges (M2, M4, and Kryo M2)
> and band saw blades so fast relative to the same wood dry?  One would think
> that the water would cool and lubricate the cut versus dry wood, but still
> it appears as if tools dull much faster.  I work mostly with English Walnut,
> "Black" Walnut root burl and Western Maple.  Perhaps having a scary-sharp
> edge is just more critical to sever the wet fibers...I don't know.  Do you?

> This group has never been short of people with opinions (albeit some more
> reasoned than others) so I thought I'd ask to see if anyone has a reasonable
> explanation.

Hi Greg, My experience has been the opposite. Dry wood dulls the tool
much faster for me.
I actually look forward to the green stuff. Bob