I have a mill with a 56” head saw that runs at 600 RPM. I am planning on adding a 36” top saw to the operation. Should I run it at the same speed as the head saw?
The simple answer is that yes, the two saws that will be sawing
at the same time should definitely be running at the same speed
so that you will have the same feed and speed relationship for
both saws at any given moment.
But there is one very big problem with that answer. It all
depends on what you mean by speed. Many people in our
industry, when talking about speed, tend to be talking about
revolutions per minute, (RPM). The problem is that RPM in and
of itself is quite meaningless. The only use I have for RPM is for
it to be just one part of an equation that along with some more
information can get us to the speed that really matters.
I have an annoying problem that eats at me. I have a Frick “0” manual mill powered by a GM 4-71 diesel engine. Saw: 52” 7/8 gauge. 44 T. 9/32” kerf reg. bits with free-cut shanks. Saw 500-550 rpm. Sawing both softwood and hardwood, my problem
Your observation about what happens at the end of the cut is the most important piece of information here, aside from the lack of heat in the saw. What you are describing is a saw that runs in towards the log and then as it exits the cut it stands back up leaving a gap between the saw and the log.
In your last Sawmill Forum you wrote about how soon a saw should need to be hammered again and some of the causes. Do you have any tricks for how to make a saw last longer?
I have many. Think of the things that will
cause the saw to start having trouble and
then think about how to prevent those
We saw about 10,000 board feet of hardwood on a good day with a circular mill. We usually only get about a month out of a saw before we have to send it out to be hammered again. Shouldn?t our saws last longer than that? Is the guy we send our saws to doin
This is a question I get asked a lot. One
of the differences between inserted tooth
circular saws and wide band saws has
to do with the sharpening process. Band
saws generally have to be sharpened
every 6 hours. The act of sharpening a
band saw will tend to cause it to need
to be benched whether or not the act
of sawing caused any issues
I was watching your How to Hammer a Circular Saw video on YouTube. I have an Armstrong Stretcher Roll. What is the ?leveling position? that you used in that video? Mine just has one roller over the other. Is there something you add to level the saw?
That is an excellent question from
a very observant person. Some of the
faithful readers of this column might not
really want to read about some of the finer
points and minutia of what?s involved in
proper saw hammering. If that is the case,
turn the page and look away now.
I just checked my collars using your method of tightening the nut from hand tight to wrench tight and measuring the movement on the rim of the saw. The rim of the saw moved .045? towards the board side. I assume that is a problem but I haven?t sheared the
You are correct that if the rim of your saw
is moving .045? in either direction when
you tighten the nut, it?s time to pull the
mandrel out and have those collars re-
machined. You might even want to order
a new mandrel and then make the switch
and send this one out to your machine
shop and then keep it around for a spare.
I have been having trouble with my saw. I suspected the sharpening was off, so I put brand new bits in, and now we have the same problem, but it is a little worse. What am I missing?
Back in the ?50s and ?60s when cars
had carburetors and adjustable points,
you could easily determine why your
car wouldn?t start. You had to figure out
whether it was a fuel problem, meaning
either a carburetor or fuel pump issue,
or an electrical issue. If you were not
getting any spark, you knew you had to
concentrate on the ignition system. Now
it gets easy. All you have to do is start
replacing the ignition components one
at a time with new ones.
What is the best way to sharpen and maintain inserted tooth circular head saws?
Here is how over 95 percent of the circular
mills operate when it comes to sharpen-
ing and maintaining their head saws: They
shut down for break, and after letting the
saw coast to a stop, someone (usually the
sawyer) goes out and sharpens the saw
with a handheld portable sharpener that
sits on the blade. The lighting is usually
poor as is the footing for this particular
This summer we seem to be having way more trouble than usual with our saws heating in the body. Do you have any ideas?
As my loyal readers will attest, I usually
have more ideas than you really want
to know about. And some of them
occasionally make some sense. In the
world of sawmill troubleshooting, one
of the things you want to consider first
is what changed at the time you started
having this trouble.
I used to work in the filing room in a band mill. Now I have a job at a mill with a circular head rig. I know nothing about circular saws and this one doesn?t seem to be running right. Where do I start?
The first thing you need to learn is that a saw is a saw, no matter if
it is a band saw, a circular saw, metal cutting saw, or rock cutting
saw. All of the same principles apply. My opinion is that any band
saw filer who knows what they are doing can be taught how to
hammer circular head rig saws in a day or two. And I assume
that anyone who is proficient at hammering circular saws can
easily be trained to bench wide band saws
No matter how much lead I add, my saw still wants to run out of the log. What am I missing?
In short, everything. I am not surprised
that, in spite of adding more and more
lead, your saw continues to run out. If
your pickup truck pulls to the right, over
inflating the right side tires or letting some
of the air out of the left side tires will only
get you so far and will certainly not correct
your alignment problem or fix the right
front brake that is hung up.
Now that I figured out that I want an F pattern saw based on last month?s Sawmill Forum, which bits and shanks should I use?
If you never intend to saw frozen or
partially frozen logs, I would recommend
using regular bits with regular shanks.
That will give you the most gullet capacity
for the F pattern. Assuming you will be
sawing frozen or partially frozen logs at
some point there are a few different ways
that you can go.
Last month you covered the different saw thicknesses. I plan to order a new saw and I was wondering which pattern is the best?
Which is best will depend entirely on your
individual application. And I should add
that your choice shouldn?t depend on
what you favorite mill supply house has
in stock and it also should not depend on
whatever pattern your grandfather liked
best. No one pattern will be the best in
We are looking to buy a new saw, but the only one we can get from our distributor in a reasonable time frame is a 6 x 8 gauge instead of a 7 x 8 gauge saw like what we have been running for years. Do you think that will be a problem?
It definitely won?t be what I would call
?a problem.? But that doesn?t mean it is
the best solution either. If you are really
hurting to get a new saw quickly, it just
might be your only viable solution.
Personally, I am not a big fan of 6 x
8 gauge saws.
In last month?s Sawmill Forum, I touched briefly on worn out saws as opposed to saws that had been deemed to have been hammered too much.
8 THE NORTHERN LOGGER | MARCH 2022
BY CASEY CREAMER
Let me first say that worn out is a relative
term. A saw that is worn to the point where
it will no longer stand up to the rigors of a
high production mill may still be perfectly
fine for a medium production mill. When
that saw becomes no longer viable for the
medium production mill, it could still have
plenty of years left in it for a small handset
mill. The beauty of inserted tooth saws is
that they don?t get smaller as you sharpen
them like band saws or solid tooth circular
saws. When treated properly, saws can
last a very long time. But that doesn?t
mean they will last forever.
When has a saw just been hammered too much?
guess I will have to say that a saw has
been hammered too much when it was
hammered by someone who didn?t know
what they were doing.
I know you want the saws to all be flat on the log side. Just how flat is flat?
That is a good question because pursuant
to my saying ?show me something that
is perfect and I will show you something
you didn?t measure close enough?, there
is no such thing as perfectly flat. So, now
the question becomes: ?How flat is flat
Wherever you find a sawmill, re- gardless of what type, you will find that they all have about the same problems as any other sawmill.
I recently received an email from a saw-
miller in South Africa. He started with:
Could you perhaps advise as to how
many mm the light gap should be and
where it should be using a straight
edge on the radius and where on the
blade considering a blade of 950mm
running at 940 r.p.m.
Looking forward to your reply
When you hammer saws, you don?t just pull the saw out of the crate, clean it up, and begin hammering on it. You have to inspect the saw to see what is out of spec and by how much.
saw is finished it should be flat on the log side, with an acceptable
amount of wobble, and the right amount of tension in the
right location. So, after cleaning the saw, you check to see how
much wobble it has and if it is flat on the log side or dished one
way or the other. Then you check the tension to see how that
looks. After that you start to formulate a strategic plan as to what
you want to do first to correct whatever is wrong with the saw and
to find the most efficient way of getting it back to flat on the log
side, with an acceptable amount of wobble, and the right amount
of tension in the right location.
I am having trouble with my circular saw heating and running out of the log. I have talked with a number of experts, and some said to give it more lead, while others said that my saw must be dished the wrong way. I was also told by some to use the guides
The short answer is that you should follow none of this advice. These well-meaning so-called experts really don?t quite understand what it takes to make a sawmill run properly. They have some ideas about how to sort of get by short term, but their solutions will not work to fix your problem.
When you are straightening a saw with a hammer, how do you know how hard to hit it?
The easy answer is that we don?t
know for sure. Before I get started,
I should tell you that saw doctors
don?t usually use the term straightening
a saw. We call that leveling a saw. Why
do we use that terminology? Simple: we
want you to think that we are the only
ones who know anything about working
on saws. And in keeping with historic saw
doctor tradition, we don?t really want any
of you to know how we do what we do.
During the early days of my career as a saw doctor I was a sponge for information that pertained to what I was undertaking. Of course, being a saw doctor isn?t just about hammering saws.
There are a lot of variables in any sawmill, large or small. When a mill isn?t running properly, it can be hard for the sawyer and/or mill manager to immediately determine the exact cause so they can resolve the problem. Does the saw need to be hammered? Does the saw just need to be sharpened accurately? Or does the saw now need to be hammered because you ran it with inaccurately sharpened teeth that also need to be corrected?
Fix it Properly if You Want it to Run Properly
When a new customer makes the arrangement to come to my shop for the first time to have their saw hammered, I ask them if the mill will be running while they are at my shop. If the answer is no, I then ask them to bring their loose collar, their sharpener, and their swage (if they are using one) with them. This is an excellent time for me to get this new customer started out on the right foot.
Do solid tooth circular head saws get hammered any different from inserted tooth circular head saws?
Let me first say that a saw is a saw. That means that all saws?large diameter, small diameter, band, circular, inserted tooth, solid tooth, carbide tooth, wood cutting, metal cutting, rip, or crosscut?all get basically hammered the same way. Some of the differences have more to do with rim speed and feed rate, and there are a few differences based on what the saw needs to do.
Every now and then someone asking
for troubleshooting help starts out
with the statement that they have
checked everything. Earlier in my sawmill
troubleshooting career I would assume
that meant that I had to look for the proverbial
needle in a haystack.
Here is one that a lot of us saw doctors encounter every now and then that can be easily overlooked and yet cause a number of fairly minor problems. Occasionally we will notice when cleaning a saw prior to working on it that the guides are set incorrectly
Let me first say that although inserted
tooth circular headrig saws all have
a set of what we call guides, that
does not mean that they are considered
to be ?guided saws.?
Does a new saw need to be hammered?
The simple answer is yes. That
leaves me plenty of room here for
the complicated part of the answer.
All new inserted-tooth circular saws come
from the factory having been hammered
and are considered to be in ready-to-run
condition. It is common during the manufacturing
process to have to hammer
each saw more than once.
How many years have you been hammering saws?
People keep asking me that question. And I have to tell you that I didn?t like the question forty years ago, and I don?t like it any more today.
It doesn?t matter whether you are a medical doctor or a saw doctor ? in either case, you are probably not at the most competent point in your career during your first year of practice. But beyond that first year, all bets are off. As far as I am concerned, it is not how long you have been doing something that counts, but rather what you have learned along the way.
Just wondering if you have a recommended torque value on the saw collar. The only answer I can get from anyone is ?Just tighten her up and wrap the wrench a few times with a hammer.? I?m a bit more precise than that, but if that is the only answer I can g
The tension part of saw hammering
is possibly the least understood
concept that we deal with. I readily
admit that once I learned how to hammer
saws, it still took me quite a while to get
an adequate handle on that particular
I have been having trouble with my saw heating in the middle and running out. Everybody I talk to tells me to give it more lead. I am running close to an eighth inch right now. What should I do?
The first thing you should do is to find some people who better understand what lead is actually for and how to make a sawmill run properly. It has been a very common misconception for many years that you can cure whatever ails your sawmill by just giving it more lead.
Here is an interesting case. I have been doing saws for this mill for many years. They usually bring me around six saws at a time. They rarely have any saw emergencies. The saws show up. I get to them when I get to them. They pick them up and I don?t hear
Every now and then, over the years,
the mill manager would let me know that,
although usually all of the saws ran great,
one of them would give him problems.
The symptom was always the same:
As soon as he hit the first cut, the saw
drastically dove out of the log.
We have been having trouble with our circular saws heating lately. What if I run water on them while sawing? Would that solve my problem?
It may possibly compensate for your problem a little so that you
can finish up today?s sawing. Later, you can then find the cause
of the problem and get it fixed. But running water on the saws
will definitely not actually solve your problem.
How long does it take to learn how to hammer a saw?
The simple answer is, a lifetime. Let me explain my thinking behind that wise guy answer before I get to the more useful answer to your question. One of the traits that most successful saw smiths share is that we are always learning.
How do you straighten bent shoulders on an inserted tooth circular saw? Is this something I can do myself, or do I have to leave it to a pro?
The answer to both of your questions really depends on how badly bent the shoulders are. If the shoulder is just slightly bent to one side, it is a fairly simple fix and one that you should be able to accomplish on your own.
This is somewhat of an add-on to last month?s Sawmill Forum. It had to do with a situation where I had hammered six saws for a customer and all but one ran fine.
Here is a totally different case with similar math, but more variables. I once ran into a situation where someone purchased a new saw from someone other than me, but the factory asked me to look at the saw because the mill was having trouble with it.
I have always wanted a clearer understanding of what the tension is you refer to and what a hammer blow does to affect tension. I assume it has something to do with moving metal in a certain technique.
The tension part of saw hammering is possibly the least
understood concept that we deal with. I readily admit
that once I learned how to hammer saws, it still took
me quite a while to get an adequate handle on that particular
subject. Just the use of the word tension can be very confusing
When you do saws, do you use a hammer or a roll, and which is better?
My first answer is yes. I use a hammer and anvil to do leveling
and tensioning, and I also use a stretcher roll to do tensioning,
and I use a leveling setup on the stretcher roll to do leveling.
Which tool is better depends on exactly what you want to do
to the saw at any given moment during the saw hammering
I had a customer bring me a saw to be hammered and what transpired was something that happens every now and then.
As many of you know, I hammer saws while the
customer waits with the saw, or saws, on a regular basis.
That not only saves the customer a trip, but it also gives me
a chance to communicate with the customer as I am working
on the saw. That communication can at times be very useful
to both of us. I get to compare what the saw is telling me with
what the sawyer is telling me about what trouble he was having
with that particular saw. And the customer often gets a few
hints about how to make better use of the saw.
Our mill saws a bit of dry hemlock successfully. But now we are sawing some dry spruce and we are having trouble. Do you have any ideas??
First, don?t saw dry stuff. Band and circular head saws were designed to saw green logs. Everything about their tooth geometry, and their feed and speed relationship was engineered for sawing fresh timber.
I have a vertical edger. Do those saws ever need to get hammered?
Most saws need to be hammered at one time or another. This means
that every type of saw that I can think of needs to be hammered, at
least during the manufacturing process. Even hand saws have to be
straightened during the manufacturing process and if you put a kink
in one during use, it will certainly need to be straightened again.
I recently had some personal computer trouble that involved
a lot of in depth troubleshooting. Actually, I still
don?t know if the problem is resolved because it was (or
is) intermittent. This frustrating experience got me thinking
about sawmill troubleshooting and how it differs.
I have a 25 year-old scragg mill. I have been a sawyer for 20 years, running a circular saw and a band saw at times. I have had several discussions with the maintenance guy here about changing saws on the scragg. The question is: when one saw breaks down,
That?s a great question. The answer, as usual, depends on a
number of variables. If I knew for sure that only one saw
had a problem, I might opt for just changing that one. But I
suspect that would be unlikely unless we were talking about
breaking a shoulder on a saw. If the saw broke a shoulder,
it would be wise to change that one and send it out for repair?
unless that pair of saws has been in service for a long
time, in which case this would be an excellent opportunity
to change and service them both.
We operate a sawmill and we seem to be getting a lot of sawdust buildup on our bandsaws when we cut white ash. I was wondering if you could send me any info on tylosis in white ash and how to prevent sawdust buildup on our bandsaws?
Tylosis? I am not a botanist. I am just an old saw doctor. I
know nothing about tylosis. But because I used to hammer
saws for a number of handle mills, I am quite familiar with
the pitch build-up associated with sawing ash.
It is no secret that I do a lot of sawmill troubleshooting. What some of you may not know is that I use two totally different methods.
The other way I troubleshoot mills is via phone and/or
email. This is a totally free service based on the fact that
I have no travel expenses and often I am able to work on
saws while talking on the phone.
When you are fixing a saw with a stretcher roll, how do you know how hard to push on the lever?
In the tradition of the old secret sect of saw doctors, the
answer would be ?you just know.? My faithful readers all
know that I don?t subscribe to the old order of secrecy
any more than I subscribe to the theory that saws are
supposed to be dished so that they can stand up straight.
When you go to someone?s mill to troubleshoot it, what is your basic procedure? Like where do you start?
There are two somewhat different types of troubleshooting
sessions. One is where you have a problem today, which
needs to be resolved right away so that you can keep sawing
for the rest of the day. Often, this type of situation is
based on a problem that just showed suddenly as opposed
to one that has been festering for quite awhile. I suppose
you could call this an ?immediate? troubleshooting session.
I have a softwood mill running a 56? 2 ? pattern saw at 900 RPM. I have been shipping my saws all over to get them hammered and it seems that nobody can get these saw?s right. Doesn?t anybody know how to hammer saws anymore?
The end result that there is still a percentage of selfproclaimed
saw doctors out there who actually don?t agree
on what a properly put up saw is supposed to look like. So if you are shipping your saws around, chances are that at least
some of the people working on them are not even aiming
for the right target.
How long does it usually take you to hammer a saw?
Most Northern Logger readers are probably expecting me to
come back with one of my typical attitude-laden comments that
might go something like, ?that depends on how bad the saw is or
what condition the saw is in.?
When is the right time to take my saw off and get it rehammered?
Let me first say that in my opinion, it is usually more efficient
and therefore more cost effective to make accurate lumber
instead of mis-cut lumber, even if your customers don?t need
or notice the accuracy of your end product.
How do you hammer a circular saw?
In this case you asked how do I hammer ?a? saw, so I will
take the next saw I have in line to be hammered and describe
the entire process from start to finish.
One of my saws just won?t run right. The guy who has been hammering my saws for years told me that it has been hammered too many times and that is why it doesn?t run after he hammered it. What does that mean, or how many times can you hammer a saw before
Saws do wear out eventually if they don?t get completely
wrecked first. But they don?t wear out from being properly
hammered. I have to tell you that when I hear that an anvilman
says a saw won?t run because it has been hammered
too many times, it reminds me of that old school tradition
of keeping the world of saw smithing a big stupid secret.
Trends and cycles that I have seen
I remember when the small portable band mils came out.
Personally I didn?t think much of them, but they sure did
start selling like hotcakes.
I hear that you are willing to hammer saws at your shop while a customer waits. But I also heard that you only make 8:00 a.m. appointments. Why is that?
The simple answer is that sawmills accomplish quality control
by measuring boards and maintaining their equipment
properly. I accomplish some of my quality control by keeping
myself out of a situation where I might have to rush the saw
How long have you been hammering saws?
People have been asking me that question for 36 years now.
And for the past 36 years I have always felt just a little uncomfortable
about having to provide an answer.
I have a hand set mill with a 50-inch B/F circle saw and after two years of summer sawing, it dishes toward the log with no lumps or bumps. Is this normal or do I have something wrong?
Well, it is normal in that eventually every saw will have problems.
But yes, you have a problem.
How long should a freshly hammered saw last?
This is a common question. It often comes from someone who
is having saw trouble for one reason or another. The short
answer is quite simple. If your saw was hammered correctly
and your mill is set up properly and maintained properly, and
you sharpen your saw accurately and in a timely fashion, that
saw should last until you do something wrong to it. That is a
lot of ifs, or what we like to call ?variables.?
Here is a recent troubleshooting case I have been involved with
on a somewhat ongoing basis for a number of months.
What is the difference between right hand, left hand, and even handed circular saws? And what do you have to do differently when you hammer them?
Circular head saws in sawmills are usually
?handed,? meaning that they are either
right-handed or left-handed.
My edger saws seem to be spitting bits every now and then. What should I do about that?
The answer depends on a few different situations. First we
need to look at the exact cause. A number of years ago,
some sawyers who thought they were saving money would
use up the worn shanks from their head saws by putting
them in their edger saws. The misguided thinking was that
the edger saws didn?t need to carry sawdust out of the cut
as much as the headsaw.
Here is something that after 35 years as a saw doctor, has never ceased to amaze me.
I was working with a new customer who got his start
with one of those portable narrow band mills. He recently
switched to a circular mill and admittedly has a lot to learn.
As one would expect, he was having some trouble.
Whenever new customers make it clear that they run a small operation that won?t be running while they are at my shop having their saw hammered, I usually suggest that they bring their loose collar with them. This allows me to check the taper, which can ha
The fast collar, of course, is the side more likely to have
problems, but it?s not as easy to bring along because it?s
more or less permanently attached to the mandrel shaft.
Pronouncing the loose collar to be good enough, therefore,
doesn?t necessarily mean that the fast collar doesn?t need to
Every profession has its own grapevine. Among themselves, many saw doctors will discuss interesting things they found while troubleshooting mills, or interesting saws they recently worked on?or of course?some of their more interesting customers.
One of my colleagues recently shared a troubleshooting story
In the 60s being square was considered a bad thing, but in some of today?s sawmills, squareness is everything.
If you are sawing everything on your headrig, then squareness
is probably not a big priority. That?s because in that situation
an out-of square-cant will still produce saleable lumber. But if
your headrig is just making cants to send to a resaw, squareness
becomes a huge issue. And if it?s a big issue for you, the
mill owner or general manager, then of course becomes a
very important issue to people like me, who service saws
for a living.
You are not going to believe what I heard today from one of my customers
Today I had an appointment with an old mill customer that I haven?t dealt with in quite a while. Fortunately the mill sent its relatively new head sawyer. I think he had been in that position for just a couple of months. He was looking forward to gaining some knowledge and as many of my customers will testify to, I am opinionated enough that I am always ready and willing to share my many opinions on sawmilling, and more. As I like to point out, ask any two saw doctors a question and you will get at least three opinions.
I run my 52? saw at 850 RPM. According to some of your articles in this magazine, that is too fast. I like that speed and I have noticed that when I hit nails and other things in the log I am much less likely to break shoulders or even bits in my saw. Wha
It?s like driving your four-cylinder car in first gear all the time. It will keep carbon away from your valves, and you will never get a speeding ticket on the highway, but at what cost?
I can understand your contention that your saw is less likely to break shoulders or bits. Of course that?s because it?s grind- ing the wood instead of chipping it. Or to put it another way, instead of each tooth taking the appropriate sized bite, your saw is just trying to rub the wood into a board.
I got a saw in from one of my customers and appar- ently the sawyer wrote on it ?scrubs?. This is not one of those mills where I have the opportunity to talk directly with the sawyer. What do you think he means by ?scrubs??
Most likely the term ?scrubs? is sawyer-talk for a situation where the saw runs out of the log and therefore rubs the log when the sawyer gigs back the carriage. Because the saw ran out of the log, it will try to stand back up straight when exiting the cut, but it can?t because the log is in the way. If the saw had cut the right path, it would not be touching the log when the carriage reverses.
Should I hammer saws any differently for a mill that has a vertical edger instead of a regular edger?
Let me first expand your question to include mills that also have a line bar resaw.
If you are really hammering saws to a close enough toler- ance, the answer would be no. On the other hand, you may be hammering saws well enough to work okay on mills that don?t have a vertical edger or a line bar resaw. In that case my answer changes.
The fact that you are asking this question suggests to me that you are having trouble getting your saws to run properly on a mill with a vertical edger. That also tells me that your saws may be close enough to run good enough for your custom- ers who have mills with conventional edgers and no resaws, but they may not be good enough to withstand the scrutiny that happens at mills that have vertical edgers and/or resaws.
I was hammering a saw today that was just weird enough that I thought I should share the experience with Northern Logger readers.
Part of my job as a saw doctor, when I am not out trouble- shooting mills or training budding saw doctors of the future, is to hammer saws. What does that mean? In the simplest of terms, the goal when hammering a saw is to undo the last thing that happened to it. After a number of years of experience, it?s usually easy to see what went wrong at the mill by inspecting the saw. Fixing it then boils down to reversing whatever happened to it.
Since it is my job to counteract whatever happened to the saw last, the first thing I do after thoroughly cleaning it is to try to determine the last thing that occurred. Sometimes the answer to that question is obvious, like when a huge set was made while still in the cut. Other times you have to dig a bit deeper and may conclude that you might never know exactly what happened
I have an old wooden handset mill. I used to take my saws up to the same guy for 35 years to be ham- mered and they always seemed to run okay. He has since retired and I have taken my saws to a couple of different people and after repeated attempts I am s
The first rule of troubleshooting sawmills?or anything else for that matter?is to ask what else changed at exactly the same time that the trouble started.
Rule Number Two is that once you find the main cause of your trouble, you should go ahead and check the rest of the mill to see what else might have been mis-adjusted in an ef- fort to compensate for the problem.
Sawmill myths and misinformation
When I first started hammering saws, I quickly became aware that this industry was chock full of some incredible myths and old wives? tales, although it wasn?t the wives who were spreading these tales but rather old sawyers.
Now don?t get me wrong. There was plenty of great information to be had from these old sawyers, but the problem was that although there was lots of good information, mixed in with that was a little bit of really bad information.
The Value of Communication
In the beginning of my career I would always tell new custom- ers to let me know if the saw doesn?t run right, and also to let me know if it does run right. It turned out that if the saw didn?t perform the way they wanted, I might hear from them. There seemed to be an equal probability that they would simply find someone else to work on their saws, assuming that I was just one more saw doctor who didn?t really know what he was doing. And, who could blame them for thinking that way? At the time there were some saw doctors practic- ing who really didn?t know what they were doing. But who knew? Saw hammering techniques were closely guarded secrets at the time, and customers didn?t have a good way to tell the difference between a competent saw doctor and a wayward one.
Here is a question I am asked every now and then: ?Do you believe in using a stretcher roll instead of a hammer??
Let me first say that whenever I hear that question, it soon becomes apparent that the potential customer is having problems with his mill and is trying to find out if his saws are being hammered correctly, or if there is a problem in the mill. Sometimes it?s both.
How can I tell if the guy hammering my saws is doing it properly or not
One would assume that if your mill is running and you are making lumber and showing a profit, then your saws must be hammered correctly. Unfortunately, life isn?t that simple. You might be producing lumber and making a profit, but are you producing as much lumber as you can, relative to your equipment? Are you consequently making as much profit as you should be? If not, I suppose that is why you are asking the question.
How hard is it to teach someone how to hammer circular saws?
The answer to your question really depends on which method is being taught. Just as there is more than one way to skin a sawmill, there are also many different ways to go about hammering circular saws and of course benching wide band saws is no different in that respect.
Because saw hammering used to be such a well kept se- cret, resourceful would-be anvilmen had to resort to being completely self-taught which in turn resulted in many more improper methods than good ones. Once you get past the improper hammering methods, you find that there are still many slightly different methods that are acceptable in today?s world of sawmilling.
What is the normal speed range for a properly tensioned saw? One of the guys is trying to tell me that our saw is tensioned to run from 300 to 550 rpm, that sounds like too wide a speed range based on what I read in your article about harmonics and tensio
That is way too much range. Setting the correct range depends
on the size of the saw. If you were running a 48? saw
at 500 RPM, which is too slow anyway, and you hammered it
for 500, it would probably still work at 300 which is still too
slow because it needs so little tension that there really isn?t
much of a difference between putting in enough tension for
way too slow or putting in enough tension for even slower
than way too slow.
But if you hammer a 60? saw at 550, which is a normal speed
for that size, it would not run properly at 300 because that
is way too slow for the amount of tension to make a 60?
saw run properly at 550 RPM.
Now that winter is coming, what should I be doing differently in my mill?
Actually if you are doing everything properly in your mill, not
much should change for you in the winter. But there is one
problem with that logic.
Nothing will ever be perfect in anyone?s mill. The old expression
that comes to mind is ?show me something that?s
perfect and I?ll show you something you haven?t measured
close enough.? So how good is good enough?
I will be bringing my saw out to you to get worked on. I noticed a big orange sticker on the crate that says ?do not lay flat.? It is a long drive from Vermont to your shop. Do I have to stand the saw up in my pickup truck?
No. It won?t hurt your saw to lay flat in the back of a pick
up truck. But there is a legitimate reason that some of the
saw manufacturers put that sticker on their crate when the
saw is new.
At one time or another almost all saws will get to take a trip
being shipped via common carrier on a tractor trailer filled
with other miscellaneous freight. Fortunately, saw crates are
traditionally round so that instead of having to have a forklift to
move it you can always just roll it anywhere you want it to go.
The more things change the more they stay the same. A true story.
A long-time customer of mine sold his automatic circular mill
to someone who moved it to their own location and was in
the process of setting it up when they called me. I knew right
off the bat that they must be new to this business because
they had the notion that they should ship their saws out to
me to be hammered and returned to them before they started
up the mill for the first time.
Sometimes the most important question you can ask is ?why?? If you are a sawmiller getting advice from another sawmiller or your local saw doctor, don?t just take that advice as gospel. Ask why that person thinks this is the right way to accomplish whatev
As a saw doctor, I often have to get information from sawmillers
about some of the specifics about how their sawmill is
set up, such as RPM, hand, feed rate, species sawn, etc. During
that process, as soon as I hear a number that seems out of
whack to me, I have to ask why they do it that way.
There is a real good chance that they have a good reason
for doing whatever it is that they?re doing that way. If they
can explain the ?why? of what they are doing, I should be
able to learn something new. But just hearing how they do it,
without the context of why they do it that way, doesn?t do
me much good. Having the data, along with a good contextbased
explanation, can make all the difference in the world.
I just hit the carriage with my saw and wrecked it beyond repair as you can see from the pictures. I use the larger pin holes in my saws. Do you think that played a part in the outcome?
Let me first say that the saw is not beyond repair, but upon
close inspection it appears that the cost of repairing this saw
would exceed the monetary value of a used saw. It would
cost less than the price of a new saw, but anytime the repair
cost starts to exceed a $1,000, I tend to advise purchasing
a new saw instead.
I think I have collar trouble and I need to get my collars resurfaced. Can that be done with the mandrel in place or do I have to take it out and send it to a machine shop?
If you think you have collar trouble you probably do. It is sort
of like if you think you snore a little at night, chances are that
you snore loud enough that your neighbors are well aware
of it and are not too happy.
Collar trouble is a very common problem that often goes
unnoticed for quite a while, until you are having enough
unexplained saw trouble that someone like me suggests that
you check your collars.
Last month we talked about getting a smoother finish on your ?rough cut? lumber without using a planer. Who wouldn?t want a smoother finish on their lumber? Even if your customer isn?t asking for a better finish, the smoother each board is, the more valua
I?m going to assume that everyone who read last month?s
Sawmill Forum got right to work at getting all of the inaccuracies
out of their track, carriage, mandrel, and collars. That
was the hard part. Here comes the easy stuff. All you have to
do is make sure your saws are being hammered by someone
willing to work in the closer tolerances needed to generate
much less wobble in your saws.
Now comes the easiest part:
I have a scrag mill and I need a little better finish on the cants I am producing. Should I get some saws with more teeth to produce a finer cut?
Let?s first realize that by design, scrag mills tend to be relatively
crude machines. They are not as crude as a firewood processor,
but they would be considered crude in comparison to
the average modern headsaw and carriage combination and
certainly crude and inaccurate compared to a line-bar resaw.
That doesn?t mean there aren?t things that can be done to
improve the accuracy and even the smoothness of the finish.
It just means we have to work around some of the basic
It seems like I get into this argument from time to time: Comparing a production band saw and a production circle saw in good working order, the band saw will tend to cut more accurate lumber than the circle saw, reason being there is less stress on the b
let me first say that I completely disagree with your assertion
that a production band saw in good working order is capable
of better accuracy than a circular saw in good working order.
It looks like my saw has a crack in it. What should I do about that?
A lot of people will think that my first question will be where
is it cracked. Wrong. My first question is, are you sure it?s really
a crack instead of a nasty scratch?
I have saved a lot of saws from the scrap heap--or should I say
the sign maker--by being able to determine that the obvious
crack was in fact just a scratch that looked just like a crack.
Hi Casey, I have been a fan of yours for years and just bought another book because the first was falling apart. I have owned a small sawmill since I was a young man, and am just finishing up starting it back up. What I was hoping you could help me with i
The splitter should be located as close to the rim of the
saw as possible to avoid the problem of shims sneaking in
between the splitter and the log and pinching the saw. If all
of your saws are not the same diameter, mount it so that
it works for the biggest one, or create a way to adjust it
for different size saws.
I can saw just about everything, except when it comes to bigger white spruce. I use a 50-inch saw, with 9/32 bits, at 600 rpm. The saw tends to dive into the log from time to time. Would a little less tension help this situation?
I can?t imagine that white spruce would give you a problem,
unless it is the ?bigger? that is causing your problem. Spruce
can be a bit fuzzy, so maybe going to 5/16 bits would help. But
if you lack side clearance, I would expect the saw to run out
instead of in. Is there any chance that you are having issues
with the alignment of the spreader, that only show up when
sawing big white spruce?
I have a hand set mill with a 50-inch B/F circle saw and after two years of summer sawing, it dishes toward the log with no lumps or bumps. Is this normal or do I have something wrong?
Well, it is normal in that eventually every saw will have problems.
But yes, you have a problem.
I just finished working on one of my customer?s saws. To my surprise it had a very severe bend at the color line on the log side and then another severe bend in the body on the board side. I also noticed that the guideline was very shiny on both sides. Wh
Fortunately what you are describing is a pretty rare occurrence,
but not so rare that I haven?t run into the same
situation a few times in my career. The simple answer is that
the saw you are describing actually had at least 2 separate
and fairly major accidents.
On a properly tensioned saw on a proper mill, does the saw sometimes take awhile to saw straight after being straightened?
Absolutely not. If it really is a properly tensioned saw on a
proper mill, it should saw properly. Of course, we are assuming
that properly tensioned saw on a proper mill was
sharpened properly and that the saw was manufactured
properly so that there are no defects in the centrality of the
vee groove and that the teeth were manufactured properly
and sharpened properly.
I have an old hand-set mill with a 46? saw with 30 teeth in it that I run at 540 RPM. I have been trying to run it with a 60 HP diesel tractor and it seems like I just don?t have enough power. How much more power do I need?
Many, many years ago I asked an old timer how much horsepower
it takes to run a sawmill, and he said about 100 more
than you have. I think his point was that there is no such thing
as too much power.
There are some
folks who assume
that power requirements
related to the size
of the saw. Actually,
plant couldn?t care
less about the saw?s
diameter. That?s because
the part of
the saw that draws
power is the tooth.
The Power of Observation Whether you are a saw doctor troubleshooting (diagnosing) a sawmill, or a medical doctor diagnosing (troubleshooting) a person, the power of observation plays a huge roll in the process.
Take this photograph that somebody sent me the other day,
for example. I don?t know which mill the picture is from so I
don?t know any more about the mill than what you and I can
see in the picture. It may look like just another circular saw
headrig to you, but here?s how I look at it:
I recently bought a used circular saw at an auction, but it only has the small pin holes in it and my mill uses the bigger ones. Can I drill that myself with a hand held drill?
Your saw needs to take a trip to a machine shop that has a big
enough machine to do the job. They would either use a large
radial drill--or better yet--a very large milling machine. There
are a couple of things that will surprise a lot of people about
getting something as simple as a couple of holes drilled in a saw.
I have a circular mill that produces about 10,000 board feet of hardwood per day. I am running a 56? saw with 50 9/32? bits on the headsaw. What can I do to increase production, utilization, efficiency and profits?
Better utilization generally equals better profits although there
are no free rides in this business--or any other business, for
that matter. Better utilization will always come at a cost. The
question is whether the gains will outweigh the costs or not.
In some ways, it?s simply a math problem.
As a saw doctor, what is the one question that all newbies feel compelled to ask you when they get their saw hammered for the first time?
Every profession has one of those questions whether you?re
a realtor, a car salesman or a plumber. Aside from the familiar,
?how much does it cost?? question, the one thing that all budding
sawyers ask during their first saw hammering session:
?How long can I expect the saw to hold it?s hammering?? or,
simply ?How long will this last??
I thought this month I would share with you an email I just received from a sawyer in the Upper Peninsula of Michigan.
I have been sawing hardwood and softwood for
over 30 years on a hand-set mill, 50-inch circle insert B style.
I would like to see if you agree with me on a few observations.
Frequently asked questions:
So, the caller says the saw is running out and the first thing I
ask is what the teeth look like. Are they sharpened accurately?
I am hammering a circular saw for one of my customers and I seem to be stuck with a tension problem.
Although there are very few absolutes in the world of saw
hammering, there is one rule of thumb that you can usually
count on. Remember that a finished saw can be described
as being flat on the log side, with an acceptable amount of
wobble and the right amount of tension (stretch) in the right
Today?s politics: Over the past twenty years I have seen American politics becoming increasingly polarized. It has now gotten to the point that Washington, DC is no longer able to get anything done in any sort of reasonable manner that will work for anyon
The only thing that seems to make sense in today?s politics is all of the politicians? abilities to blame other politicians for the problem. Well, now they finally got it right because they are all to blame. Apparently there is one thing they sort of agree on.
Customer Service When we hear the term ?customer service,? most of us think about the retail trade. But we all have customers and we all should be using good customer service techniques. This applies to loggers, sawmillers, and even cantankerous old saw d
The first maxim that comes to mind when you think of customer service is ?the customer is always right.? To me, that mantra is right up there with ?if it ain?t broke, don?t fix it.?
Would you be able to provide written instructions on how to swage a saw bit?
I am sure it would be a lot easier for me to show you than to put it in writing, but who ever said life was supposed to be easy? Swaging bits on an inserted tooth circular saw is fairly easy, but there is a certain amount of feel for it that you have to develop that is hard to describe in writing.
I?d like to get a spare saw for my mill, but at the moment, a new one just isn?t feasible. What should I look for in a used saw?
Inserted tooth circular saws in one form or another have been in existence now for more than one hundred years. In that time many patterns and styles have come and gone and in some cases, thankfully so.
If you happen to be in the market for a used inserted tooth saw, the first thing you want to check is to make sure that the blade does not have an obsolete pattern.
To clear up an argument we have been having here at the mill, can you tell me which is better, to feed too slow or too fast?
The proper feed rate is really derived from a relationship between the speed of the saw, the number of teeth per inch in the saw, the species being sawn, the gullet size, and the depth of cut. That is known as the ?feed and speed relationship.?
The Virtues of Mill Cleanliness:
One of the things that the most efficient, productive, and profitable mills have in common is that they all look relatively neat and clean.
I seem to be having a problem breaking shoulders on my saw without hitting any metal. What could cause this problem?
As usual, for any given symptom in a sawmill, there are always
lots of possible causes.
The first thing to look for is bit creepage.
I just got a new spider gauge to check the side clearances on my teeth. Do I set it up to a new set of bits?
If you had a new set of bits that were perfect that you put in a saw that had perfect sockets and no bent shoulders, that would be the ideal opportunity to set up your spider gauge. The only problem is that nothing will be perfect if you measure it close enough. It would be unlikely that any one of those three things would be perfect and just about impossible for all three of them to be perfect at the same time.
I have an old antique shingle mill. It doesn?t seem to want to feed properly, because I suppose it isn?t cutting properly. What do you suppose is the problem?
All circular saws operate on the same principles, as do band saws. Shingle saws have a bit of a different configuration as compared to headrig saws, but they are doing essentially the same job as any rip saw.
Many of my faithful readers already know what I am about to say next. Have you looked at the sharpening? As with any saw, that is always the first place to check.
The only difference between troubleshooting winter sawing problems and summer sawing problems is that the offending winter sawing problem can be much more subtle, and yet still create problems for you. In other words, there are things that can be out of a
Inaccurate sharpening is always a first on my list of possible causes of saw trouble. Grossly inaccurate sharpening will never work, no matter what the season is, but it is true that during the more forgiving summer months you are able to live with a small amount of inaccurate sharpening. Come winter time you had better watch out because that small inaccuracy that you can?t even detect without your glasses on (if you are over 40) can easily be enough to start causing major sawing trouble.
Winter Sawing: It?s been a fairly cold start to the winter in the Northeast this year and as a result some of the saws out there are back to their old tricks.
Let me first say that if your equipment is in
good shape you should be able to saw frozen timber properly.
However, just because your mill was in good enough shape
to saw unfrozen timber properly, doesn?t necessarily mean it
is good enough to get the job done with frozen logs. Frozen
logs are not impossible to saw, but they certainly do present
a bit more of a challenge than the unfrozen ones.
He said ?given the current state of the economy, aren?t you sorry you taught all of those people how to hammer saws??
Of course my answer to both of them was exactly the same. I
am glad that I was willing to teach people this profession and
I am especially proud of the ones I taught who have gone on
to become really good at hammering saws. And I am proud
of myself for having a hand in that education.
Disclaimer: The best medical advice a saw doctor can give you is that if you get your medical advice from a saw doctor, you should see a psychiatrist. That should be all the disclaimer that you need.
Control is the main key.
Statistics say that the better your control, the less likely you
are to develop the nasty side effects associated with diabetes.
Keep in mind that those are only statistics. There are many
cases where a person with the best control develops side
effects while a person with lousy control remains side effect
free. But you still have to put your money on the statistics
and make sure that you are doing your part to keep the
odds in your favor.
It seems this is a problem that, while odd for most conventional saw mills, is fairly common with scragg setups.
Generally when a conventional-head rig sawmill has trouble with a saw, the saw is running out of the log as opposed to running in. Occasionally I will see a saw with reported symptoms of running in. In these cases, the saw appears to be dished towards the log side--either from an operational incident, or from being hammered by someone who subscribes to the old and worn theory that circular saws should be dished towards the log side so that they can stand up straight when up to speed.
Sometimes when I am trying to figure out what is wrong with my mill, I just don?t know where to start. What is the first thing to check usually?
When it comes to troubleshooting techniques, there isn?t much of a difference between saw doctors and medical doctors, except that medical doctors ?diagnose? instead of ?troubleshoot.? Same idea; different terminology.
Here is an interesting case I had recently.
Of course the person who brought the saw in knew nothing
about what might have happened to it. But as usual, these
saws have stories to tell if you know where and how to
Casey Creamer Northern Logger Columnist & Saw Doctor
Casey Creamer, 56, grew up in Bucks County, Pennsylvania,
right outside of Philadelphia. A car racing enthusiast, he
and his friends made their way up to Watkins Glen, New
We?re scratching our heads over alternatives to manually setting saw guides--looking for a safer way.
The specs I?ve read say 1/32? clearance. Can?t it be set
when the blade is stopped despite the dish in the saw?
As many of my readers know I am always willing to troubleshoot mills over the phone (or even via email) for free as long as the person on the other end can give me good, accurate data and answers to my questions.
On the other hand, there are times when either the data
isn?t reliable enough, or I just have to see things for myself
for one reason or another. That is the kind of situation that
calls for me to make an onsite troubleshooting visit to the
mill, which of course is not for free.
Here is one that had me baffled for a while.
My customer and I both noticed that the teeth were pointed
off to one side (the board side). The bits were not off center
(like from a mis-manufactured vee groove) and the bits were
not improperly side ground or mis-manufactured in any way
that I could detect.
Why does the collar line look so weird on that saw and what does it tell you?
The first thing it tells me is that you have a customer who needs you to educate him a bit. What the picture tells me is that your customer is spraying some WD-40 on the saw when it gets hot, in hopes of cooling it off so that he can keep sawing.
I have a firewood processor with a big circular saw on it. Do they need to be hammered too?
Whether they are on firewood processors, or machines that
are designed to cut tree length logs into saw log lengths, they
need to be maintained much in the same way that a circular
rip saw (head saw) needs to be maintained.
Old habits are as hard to break as the old myths that fed them. Or to almost paraphrase an old Tina Turner song, ?What?s Lead Got to do with It??
Of all of the things there are in your mill to adjust to keep your saw running properly, lead is not the one you want to mess with.
Emails, I get emails. To: email@example.com Subject: Tolerance in saw mandrel bearings
I don?t like the knock in the bearing, so it is good that it has
I am more concerned about endplay, than I am about movement
up and down.
Sawmill Forum - Trends
Trends from one saw doctor?s perspective.
2009 has been a tough year for the lumber industry, to say
the least. I have seen many of my customers slow way down,
close their doors, or go out of business.
Sometimes my circular saw just doesn?t seem to run properly no matter who hammered it or when it was done. Where do I start?
The three most important things to check first when having saw trouble are sharpening, sharpening, and sharpening.
One of the questions I am asked most is how long a freshly hammered saw should last.
My standard answer is that if the saw is running properly when
you first put it on after being hammered, then the length of
time it will perform properly is directly related to how you
and your mill decide to treat the saw.
I just wrecked my best saw. I have heard that you can?t weld more than three shoulders in a row or more than six on the same saw.
When it comes to replacing broken shoulders by welding new ones on, there are a few things we have to consider.
2. Accuracy and effectiveness.
3. Cost effectiveness.
Scragg saw blades both running out of the log.
Scragg saws operate on essentially the same set of principles that any other circular head rig operates on. You need saws that are sharpened accurately and hammered correctly with the log side flat, an acceptable amount of wobble and the right amount of tension in the right location. After that you need the right amount of lead in the saws and you have to have good collars that support the saws without dishing them one way or the other.
Sawmill Forum: After close inspection of the log and the blade I discovered that one of the teeth had broken off and embedded in the log long enough for every other tooth to slam into it. On close inspection, the point of the shoulder (that?s where the ba
Damaged tip of shoulder.
My basic philosophy about welding these saws it that it is best to avoid it if possible. It?s not that I mind welding saws or making money, though.
Sawmill Forum I discovered that the shaft broke right inside of the third of four bearings. Should I have it welded back together?
Knowing that the pins are supposed to shear first, let?s see
if we can solve the mystery of why the shaft broke.
Sawmill Forum I had a bit of an accident with my saw.
"Two diametrically opposed blue spots."
The simple answer is to screw up your courage and open the throttle up to your normal speed. You will be amazed when that crazy wobble disappears.
Sawmiil Forum - One of my saws just doesn?t seem to run right.
I have checked everything I could think of in the mill.
The track is straight and I had the collars redone and
I still have trouble with that saw. My other saw seems
to run okay. Do you have any ideas?
A saw doctor?s advice to a good friend who was recently diagnosed with a treatable, yet very serious form of cancer.
This advice should apply to anyone in that position, but I warn
you, taking the advice of a saw doctor about medical issues
does not relieve you of the responsibility of consulting with
medical doctors. I should also warn you to never consult with
medical doctors on saw related issues.
Sawmill Forum Working on 60: Saws
I have been hammering saws for a number of years
now, but every time I do a 60? saw, I seem to have
trouble with it and much less confidence in the results
than with smaller saws. What am I doing wrong? Are
60? saws that much harder to hammer?
Sawmill Forum - While You Wait
While You Wait
When I first started hammering saws for a living, it was quite
apparent that the trade of saw hammering was supposed to
be a big secret.
Sawmill Forum - Trends
Trends, from one saw doctor?s perspective.
I have seen a number of trends in the past few years that I
would definitely consider to be worth watching in the new year
December 2008 Saw Doctor
When it comes to smithing saws, can you do it all with just a stretcher roll? Is there any need for a hammer?