Back in 1992 when experimenting with Thin Kerf bandsaw blades I came across 'something'
while altering a band blade tensioning roller (most of these experiments lasted
till 1:00 or 2:00 am in the morning). This 'something' that I had discovered
has led me to finding a way to make band blades cut better, faster, and straighter.
Over time I discovered something that made blades run better, faster, and
straighter. This 'something' seemed to stabilize the band in the cut better
than anything else that I had done. Yet it was a hit and miss because I had
not yet realized what exactly was yielding the performance.
So I searched to find what it was that all the good cutting blades had in
common. In our experimenting we observed blades that cut great and some blades
that cut poorly. We saw some blades rising up in the cut, and we saw some
blades diving down in the cut.
What we learned is that we could only judge
the band by its first reaction in the cut, and if we judged the first reaction
then we could predict the second reaction. We soon found that if we could
solve the first reaction of bad cutting we in fact had solved the cutting
difficulty.
For instance if the first reaction when the blade deviates from
the cut is up the second reaction will be down. If the first is down the second
will be up. If we can make it cut straight when we enter the cut it will continue
to cut straight. There will be no second reaction. We also noticed that groups
of bands had common characteristics, such as all in one box could be divers,
or all risers, or all good cutting.
In this research we found one common thing that affected the blade more than
any other. That is after we established the things that have to be correct
for any blade to run correctly, like sharpness and side set. This extra common
thing was “flatness of the body of the bandsaw blade”. We sometimes
refer to the curvature of the bands because there in no such thing as a perfectly
flat band. We say it has a curvature because we know that it will have a slight
variation from perfectly flat to either the inside or the outside.
The solution
was to control this curvature before it gets to the sawmill. Since we knew
that the blade could not be perfectly flat we found that the best situation
was for the band to have a crack of daylight (dish or curvature) on the inside
of the band which would be the roller guide side. This band would cut better
that all others.
On the contrary if the band had a slight hump on the roller
guide side or the inside this blade would dive. Through these experiments
we learned what the band needs and we can control the flatness of all the
bands that we ship out.
There are bands that turn clockwise and some that turn counter clockwise.
We have to know the direction they turn before we can condition them correctly.
Another thing we learned is that this process has to be done after the blade
is welded. Otherwise it cannot be welded correctly. Many factors have to be
taken into consideration before we condition a bandsaw blade.
There is no such thing as a generic blade that a welding center can just cut,
weld and ship to the customer. You will see many problems if you get blades
welded that way. It just doesn't work. When blade suppliers do this they get
a lot of complaints about blades differing in how they cut from one box to
another.
Let me give you a good example:
I had a customer that purchased our sawmill and 40 blades. All worked well until
he needed more bands. As most people do, he looked for bargain prices in the
same blade brand that we sold to him (thinking that they are all the same).
As soon as he started using the bands trouble started and he could not saw
his lumber straight. He called me for help and I thought he had bandsaw blades that
came from us. Thinking this I was searching for solutions other than blades.
He struggled for a week or more and called back still having the same problem.
I
told him that I was now sure that his blades had a wrong curvature in the
body and I was puzzled as to how he got blades like that from us. He cleared
his throat and said "I didn’t buy them from you". Now I could
understand his problems. He got the generic: 'weld em' and 'ship em' bandsaw blades.
He asked me to send correct blades ASAP. We did and his problems were gone
as soon as he began to use our blades with the correct curvature. (We sell
a Advance Bandsaw Technology video and DVD that explains this and other blade problems in depth.)
I have solved literally thousands of customers problems just like this one.
It takes extra effort to send out consistent blades, and we put forth that
effort. Not that we never make mistakes, but we strive for what we know to
be correct for each customer. Knowing the problems that the customer is encountering
is the beginning of all solutions.
At Cooks Saw we need to know your rotation, the type guides, and it is good
for us to know the MFG of your sawmill. With the proper information we can deliver
the bands shaped the way that you need them to saw consistently.
By taking the bands through this process we spend twice the time with the
bands than any other company that supplies band blades.
As you can figure we cannot be the cheapest supplier. We all know that you
get what you pay for. Do yourself and your lumber a favor and buy your bands
from Cooks Saw. You will find though our blades may be a little higher they
will save you money. Our goal is to help you make/save more money."
For further information on this subject refer to earlier articles Titled:
Stop Wavy Cuts and buy our new Advanced Bandsaw Technology video/DVD mentioned above.
Until Next Time,
aka... the "Saw Doctor"
Co-Owner CooksSaw.com
Leaders in Bandsaw Technology!
