Various bandsaw questions...long
Stephen M
a real bandsaw (there was the well-intentioned gift of a really cheap
benchtop which was used twice and promptly discarded) I'm could use some
help assessing features. I'm looking at the $1k price point but the I can go
higher if there is a truly compelling argument.
I will use this saw for curved cuts, stopped cuts and resawing. Currently, I
am mostly involved in furniture making. (no bowl turning, or green wood
stuff to date). 220V is NOT a problem ( I have a 10ga 110V circuit with an
adjacent slot in the panel for just this purpose).
1. I would like >6" resaw capacity. By intuition tells me that a 14" saw
with a riser kit is an engineering kludge. If the structure could handle it
w/o undue flex, why not just put that extra bit of metal in the base line
design? Isn't that stretching motor capacity too?
2. How much resaw capacity is really required. Once again, intuition
suggests to me that extra resaw capacity, unused is a bad thing. That is, is
a larger structure is more dificult to make ridged. The Laguna 14 has a
capacity of 8.5"... (this would allow me to bookmatch a 17" pannel which is
more than enough for my aesthetic preference) How often would 8.5 that not
be enough?
3.Of what benefit is a rack and pinion blade guide?
4. I would also like to keep the weight below 350lbs. I have an upstairs
shop. I assume that removing the motor and table is fairly simple, the
moving a 200lb thing is pretty managable with 2 guys. Am I correct in
assuming that removing the motor and table is easy and removing the wheels
is a bad idea?
5. I got the Laguna free video. It spends some time explaining why their
proprietary giudes are superior. (In short, the guides come in direct
contact with the blade, and are located above AND below the thrust point to
eliminate twist, in addition the "in-contact" design eliminates
micro-flutter). This makes sense, but it IS marketing. Anyone care to
comment on if they are truely superior in a significant way?
6. How important/useful is a quick-release blade tension feature? how bad is
it if I forget to detension the blade andnot happen to use the saw to 2
weeks?
My short list looks like:
Bridgewood BW-17WBS
http://makeashorterlink.com/?W27912627 (Cheezy fence, but otherwise a nice
capacity/feqature set)
Laguna 14LT
http://www.lagunatools.com/lt14.asp (less capacity but I feel pretty
confident about the quality)
Griz
http://www.grizzly.com/products/item.cfm?ItemNumber=G1012 (Can you really
get quality at this price point?)
http://www.grizzly.com/products/item.cfm?ItemNumber=G1073 (Can you really
get quality at this price point?)
http://www.grizzly.com/products/item.cfm?ItemNumber=G0513 (aluminum
wheels!?!)
7. 1st hand comments on any of these models would be appreciated
8. One of my beefs about magazine reviews of tools is that I think all
reviews of, say, contractor saws, should have a side bar on "when does it
make NOT sense to buy a contractor saw because what you really need is a
cabinet saw". There is no doubt that the 2K machines such as the Laguna
16SE, MiniMax 16 and the BridgeWood PBS, are all the BS I could ever want,
but my gut tells me that this is overkill. Is there a compelling reason why
I would really regret going up-market? By the same token, should I give the
Delta/Jet etc... 14"-ers a closer look.
DarylRos
>Delta/Jet etc... 14"-ers a closer look.
Well, I looked at them all, and settled, quite happily, for a MiniMax 16. Quite
expensive, but a great saw.
If you are looking for a better small saw, then go with the Delta or Laguna.
The riser block is not really a kludge, since it works very well. The bandsaw
issues that no one ever really addresses are: blade quality and tension
application.
I think few people would now consider any tablesaw blade that is not carbide
based. They last longer, and now give great cuts. So why not the same for a
bandsaw. The only really good carbide bandsaw blade is made by Lennox--go with
the 1/2". The resawing is great, and will last a very log time. They are
expensive, but so are Freud and Forrest TS blades. This leads to problem no. 2:
Tension. You will never get the Delta or clones, including Jet to provide more
than 10,000-15,000 psi of tension; the American Delta more than the others
(including the cheaper, but crappier Chinese Delta-you will know which by the
price). The Laguna 16" model can't handle the 25,000-30,000 Lennox recommends,
so I assume the 14" can't either. The MiniMax gets that in its sleep.
I've used the Delta 14" and Jet 16" steel bandsaw. The Delta is plain better,
so it's also reasonable to figure the 14" American Delta is better than the Jet
and other clones. So if you don't want to go over $1,000, go with the highest
end Delta, but don't forget a good blade. Plus check out Iturra Design, for the
upgrades you will want to make the saw even better.
Bruce Rowen
>>I would really regret going up-market? By the same token, should I give the
>>Delta/Jet etc... 14"-ers a closer look.
>
>
> Well, I looked at them all, and settled, quite happily, for a MiniMax 16. Quite
> expensive, but a great saw.
I recently bought the MM16 and agree!
If you are still limited to a kilobuck you might want to look at the
MiniMax "S" series, lots of quality still but scaled down a tad from the
MM series.
-Bruce
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Mike in Idaho
Check out the new Laguna 14" with 12" resaw!!
http://www.lagunatools.com/lt14se.asp
I saw this in a side bar in FWW a couple months ago and drooled all over the
page. I own the grizzly G0555 and love it to death, but if I'd had $1k to
put down on a bandsaw I would have bought this puppy without even thinking
twice. It's a 2hp motor too (up from the previous 1.5hp).
Let us know what you decide -- oh, and if you get the lt14se let us know
what you think :)
Mike
"Stephen M" <smeier-...@primelink1.net> wrote in message
news:buolk...@enews3.newsguy.com...
George
don't have the room or the need for 16" or 24" monsters like I've used at
commercial places. Your purse may be longer and your shop larger, but I
will bet you'll find yourself doing almost all work within the capabilities
of a 14" saw.
"Stephen M" <smeier-...@primelink1.net> wrote in message
news:buolk...@enews3.newsguy.com...
> I am in the process of researching a bandsaw purchase. >
Stephen M
"Bruce Rowen" <b...@nospamnohow.edu> wrote in message
news:401009c5$1...@corp.newsgroups.com...
> DarylRos wrote:
> >>I would really regret going up-market? By the same token, should I give
the
> >>Delta/Jet etc... 14"-ers a closer look.
> >
> >
> > Well, I looked at them all, and settled, quite happily, for a MiniMax
16. Quite
> > expensive, but a great saw.
>
> I recently bought the MM16 and agree!
> If you are still limited to a kilobuck you might want to look at the
> MiniMax "S" series, lots of quality still but scaled down a tad from the
> MM series.
> -Bruce
>
I did look there, but for the $1500+ they want for an S16 or S45N, I might
as well for for the MM16
The MM16 does look sweet.
Stephen M
When you refer to the Laguna 16, were you referring to the 16 or the 16HD.
They are different saws from different maufacturers. The 16HD is really the
one that competes with the MM16.
Although I have not been looking for it, I have not seen the tension spec on
any of the websites. Do you find that that spec is available from most
vendors?
BTW $1K was a general price point, not really a limit. I would say that $2K
would be an absolute limit tax/shipping etc.
"DarylRos" <dary...@aol.com> wrote in message
news:20040122121025...@mb-m02.aol.com...
Bob Davis
shipping. Or were you just rounding to the nearest $1k? :-)
Bob
"Mike in Idaho" <m...@foo.bar> wrote in message
news:_0UPb.12805$p75....@news.cpqcorp.net...
Mike in Idaho
you want something of Laguna quality but 12" resaw is a must then throwing
in another couple hundred is a possibility -- unless he'd already up'd his
original price from say $700-$800 to $1k, then that might not be a
possibility.
I guess basically I was saying I wasn't willing to pay that much (I payed
$435 w/shipping for my G0555), but if I had been in the $1k range I would
jump at the lt14se without a second thought. (Hee, hee, it's so much easier
to spend someone elses money, huh ;)
Mike
"Bob Davis" <wrobertda...@yahoo.com> wrote in message
news:eNWPb.22253$1e....@newsread2.news.pas.earthlink.net...
Poseidon
Unisaw A100
>Isn't that stretching motor capacity too?
You might want to consult a metallurgist.
>2. How much resaw capacity is really required.
As much as you will need for a required project. This will
vary.
>3.Of what benefit is a rack and pinion blade guide?
Yes. Makes for easier up and down and the guides don't
crash onto the table.
>Am I correct in assuming that removing the motor and table is easy
>and removing the wheels is a bad idea?
Yes.
>5. I got the Laguna free video.
Around here the Laguna is a status symbol. By all means,
get one and you can be just like everyone else.
>6. How important/useful is a quick-release blade tension feature?
Blade tension became an issue because the same guys that buy
Lagunas like to let them sit for months on end lest they
actually have some saw dust appear in their shoppes. In
other words, it's pretty over blown, especially if you buy
machinery for using instead of, well, a status symbol.
snippage...
>7. 1st hand comments on any of these models would be appreciated
They are awful shiney.
>I would really regret going up-market? By the same token, should I give the
>Delta/Jet etc... 14"-ers a closer look.
Only you can answer this and by your questions I think
you've got a pretty reasonable grasp on things.
On the other hand, you could find a good used saw and if it
becomes apparent that it's over kill you can turn right
around and sell it for what you have in it.
UA100
Rick Stein
> >
> > 1. I would like >6" resaw capacity. By intuition tells me that a 14" saw
> > with a riser kit is an engineering kludge. If the structure could
> handle it
< much snippage>
if you only need 6" of resaw capacity, you should consider the
Powermatic #141, or the General #390. Both are over your stated budget
of $1000, but are frequently available on Ebay (the Powermatic at least)
well within your numbers. FWIW, I think that resaw capacity should match
your jointer width capacity. Excess resaw capacity seems wasted if you
have to rip to narrow width to face joint.
Rick
Bob Davis
sizes and features that make a continuum of pricing with price breaks about
every $200 or so. I've got the Laguna video and I watched the table saw
portion but not the bandsaw. I'll go back and watch it. Their tablesaw
made lust so much that I got disgusted and didn't watch the rest. I was
amused by the president giving his lecture on safety: "If you are a hippie,
be careful of your long hair".
Bob
"Mike in Idaho" <m...@foo.bar> wrote in message
news:QqXPb.12846$so5....@news.cpqcorp.net...
charlie b
>
> I am in the process of researching a bandsaw purchase. Having never owned a
> a real bandsaw (there was the well-intentioned gift of a really cheap
> benchtop which was used twice and promptly discarded) I'm could use some
> help assessing features. I'm looking at the $1k price point but the I can go
> higher if there is a truly compelling argument.
>
> I will use this saw for curved cuts, stopped cuts and resawing. Currently, I
> am mostly involved in furniture making. (no bowl turning, or green wood
> stuff to date). 220V is NOT a problem ( I have a 10ga 110V circuit with an
> adjacent slot in the panel for just this purpose).
>
> 1. I would like >6" resaw capacity. By intuition tells me that a 14" saw
> with a riser kit is an engineering kludge. If the structure could handle it
> w/o undue flex, why not just put that extra bit of metal in the base line
> design? Isn't that stretching motor capacity too?
>
Marketing. The DIY crowd prefers bench top, light duty stuff - cute
and
less intimidating than a BIG HEAVY SCARY Monster (the latter being the
exact
thing that appeals to many of us here). So for their biggest market
they
make the "petite" model and make the conversion to "a real bandsaw" an
option for those who are inclined to want MORE POWER, Bigger, Beefier
tools.
> 2. How much resaw capacity is really required. Once again, intuition
> suggests to me that extra resaw capacity, unused is a bad thing. That is, is
> a larger structure is more dificult to make ridged. The Laguna 14 has a
> capacity of 8.5"... (this would allow me to bookmatch a 17" pannel which is
> more than enough for my aesthetic preference) How often would 8.5 that not
> be enough?
>
Regarding ridgidity - use to be thick walled cast iron = rigidity.
Once
again, the Europeans closely examined that assumption and found that
there
were other ways of getting rigidity without adding a lot of wieght in
cast iron. The box and box plus triangle bandsaws we see today can be
just as rigid, if not more rigid, than all cast iron models- AND weigh
less.
> 3.Of what benefit is a rack and pinion blade guide?
>
A GOOD rack and pinion "blade guide" means not having to tweek your
blade guides every time you raise or lower the blade guide + guard.
If it doesn't move up and down while remaining square to the table
you start cutting trapezoids and not rectangles. Tapered veneer is
not good.
> 4. I would also like to keep the weight below 350lbs. I have an upstairs
> shop. I assume that removing the motor and table is fairly simple, the
> moving a 200lb thing is pretty managable with 2 guys. Am I correct in
> assuming that removing the motor and table is easy and removing the wheels
> is a bad idea?
>
The 2.5 HP TEFC on the LT 16SEC has got to be 75 or more pounds, with
the
cast iron table and fence coming to another 40-50 pounds. But the
16SEC
weighs about 375 so it'd be a bit of a challenge to get to a second
floor.
DO NOT remove the wheels. That's asking for a ticket to Set Up Hell.
While on the subject - you want dynamically balanced wheels - and cast
iron at that. Wheel weight = inertia = more continuous cutting power
when the teeth hit harder areas. Dynamically balanced wheels mean
smoother cutting and that's a really good thing.
> 5. I got the Laguna free video. It spends some time explaining why their
> proprietary giudes are superior. (In short, the guides come in direct
> contact with the blade, and are located above AND below the thrust point to
> eliminate twist, in addition the "in-contact" design eliminates
> micro-flutter). This makes sense, but it IS marketing. Anyone care to
> comment on if they are truely superior in a significant way?
The less the blade can move left/right or twist the better. Cool
Blocks
and the other direct contact guides have been found to work well for
a long time now. But they wear and that means they need more frequent
adjusting. The ceramic guides are direct contact, they don't wear
very quickly AND they dissipate heat well - heat being an enemy of
band
saw blades.
I picked up a set at a WWing show and eventually got around to
installing
them. Required hacksawing a little thick sheet metal but they work
pretty well. Unlike the bearing guides, the ceramic guides will work
well
with narrow blades as well as wider blades and you can set the front
of
the side guides just behind the teeth, behind their set. Of course if
you have a blade with a less than smooth joint they can be a problem.
>
> 6. How important/useful is a quick-release blade tension feature? how bad is
> it if I forget to detension the blade andnot happen to use the saw to 2
> weeks?
>
Detensioning the blade is actually doing several things. First, and
obvious,
it takes the tension off the blade and blades like that. But it also
decompresses the tension spring which is the shock absorber on your
bandsaw.
That spring, when kept compressed too long will loose some of its
springyness. That means less shock absorption and that's not good.
Finally, detensioning the blade also takes pressure off the bearings
on the upper and lower wheels. Bearings last longer that way.
As for quick release blade tension feature - is the time savings by
not
turning a knob three or four revolutions really significant? If you
change blades often - 1/4" for tight turns and delicate stuff, 1/2'
for
normal things and maybe some resawing, 3/4" for beefier big cuts and
maybe once in a while a 1 inch blade for slicing up a mini-log. If
you have to adjust the tension after each blade change a "one size
fits all" quick release could be a problem since the proper tension
for a 1 inch blade is quite different from that of a 1/4 inch blade.
Over time the spring's strength will lessen so if you rely on a
set of initial tension points for each blade width you could have
a problem with undertensioning down the road
> My short list looks like:
>
> Bridgewood BW-17WBS
> http://makeashorterlink.com/?W27912627 (Cheezy fence, but otherwise a nice
> capacity/feqature set)
>
> Laguna 14LT
> http://www.lagunatools.com/lt14.asp (less capacity but I feel pretty
> confident about the quality)
>
> Griz
> http://www.grizzly.com/products/item.cfm?ItemNumber=G1012 (Can you really
> get quality at this price point?)
> http://www.grizzly.com/products/item.cfm?ItemNumber=G1073 (Can you really
> get quality at this price point?)
> http://www.grizzly.com/products/item.cfm?ItemNumber=G0513 (aluminum
> wheels!?!)
>
> 7. 1st hand comments on any of these models would be appreciated
>
I've got the LT 16SEC - 2.5 HP TEFC motor, 12+ inch resaw, rack and
pinion guides - though plastic rack and pinion, and stamped steel
trunion. Works well though I'd prefer a cast iron trunion.
Torben is a bandsaw nut - loves doing laminated pieces using stuff
he bandsawed himself. If LT carries a bandsaw Torben probably
has used that model. If it doesn't work for him they probably
won't be selling it.
NOTE: if you can get a model with a table that'll tilt BOTH WAYS
you can cut dovetail pins without having to make an angled support
jig. The LT16SEC only tilts one way - dammit.
ALSO - mobility kit - you will move this thing several times at
least. Shoving/rocking/walking a 6+ foot tall 250-400 pound
beast around is not fun.
> 8. One of my beefs about magazine reviews of tools is that I think all
> reviews of, say, contractor saws, should have a side bar on "when does it
> make NOT sense to buy a contractor saw because what you really need is a
> cabinet saw". There is no doubt that the 2K machines such as the Laguna
> 16SE, MiniMax 16 and the BridgeWood PBS, are all the BS I could ever want,
> but my gut tells me that this is overkill. Is there a compelling reason why
> I would really regret going up-market? By the same token, should I give the
> Delta/Jet etc... 14"-ers a closer look.
AH - the age old "buy more than I need and never use the extra
capacity/
capability/power" vs "buy what I think I NEED now and then have to
buy another one sooner or later". To that I say "Buy Once, Cry Once"
(if you can afford it)
You WILL have a really nice piece of wood that's wider than 8.5 inches
and the thought of ripping it down to 8.5 inches in order to get that
bookmatched pair you want will haunt you. AND, if you have a bandsaw,
you will find mini-logs of nice stuff that you can saw into boards,
sticker and stack and wait a year to dry so you can use it. The
wider you can cut the more options you'll have a year later when it
comes to picking what you want out of each board.
Don't envy you the consumer research but you're going at it in the
right way. I'm sure you'll be happy with whatever you eventually
buy.
charlie b
Stephen M
Charlie,
Nice reponse. Thanks for taking the time. I have a couple followup questions
to your comments.
> DO NOT remove the wheels. That's asking for a ticket to Set Up Hell.
>
> While on the subject - you want dynamically balanced wheels - and cast
> iron at that. Wheel weight = inertia = more continuous cutting power
> when the teeth hit harder areas. Dynamically balanced wheels mean
> smoother cutting and that's a really good thing.
What does dynamically balanced mean? Is it like balancing a a car tire?
(spin it and add/remove material until it's even?)
. Unlike the bearing guides, the ceramic guides will work
> well
> with narrow blades as well as wider blades and you can set the front
> of
> the side guides just behind the teeth, behind their set. Of course if
> you have a blade with a less than smooth joint they can be a problem.
I understand the theory. Do you find that these guides offer a imperical
improvement, or is it tough to say without a proper control group (same
saw/blade/wood etc.. with alternative guides)?
>
> Torben is a bandsaw nut - loves doing laminated pieces using stuff
> he bandsawed himself. If LT carries a bandsaw Torben probably
> has used that model. If it doesn't work for him they probably
> won't be selling it.
Lost you there... Who's "they".
>
> NOTE: if you can get a model with a table that'll tilt BOTH WAYS
> you can cut dovetail pins without having to make an angled support
> jig. The LT16SEC only tilts one way - dammit.
>
Thanks, I had not thought of that.
George
it's hone for dull. For that, cool blocks or such.
If you have a badly ground join on your blade, touch it up or find another
supplier.
"Stephen M" <smeier-...@primelink1.net> wrote in message
news:bura1...@enews3.newsguy.com...
Stephen M
> >5. I got the Laguna free video.
>
> Around here the Laguna is a status symbol. By all means,
> get one and you can be just like everyone else.
This comming from the guy who's handle is "unisaw A100" ?!? Are all >$1000
saws "boutique" saws? or just the italian ones?
For this kind od money, not only do I want a good saw.... it had better be
fashionable too. :-)
>
> >6. How important/useful is a quick-release blade tension feature?
>
> Blade tension became an issue because the same guys that buy
> Lagunas like to let them sit for months on end lest they
> actually have some saw dust appear in their shoppes. In
> other words, it's pretty over blown, especially if you buy
> machinery for using instead of, well, a status symbol.
I would not want my first love (JTAS Jet cabinet saw) to feel rejected. So I
can't spend ALL my time with the new girl.
>
> snippage...
>
> >7. 1st hand comments on any of these models would be appreciated
>
> They are awful shiney.
That's good to know, as I'm a bit off the beaten path and it will take me at
least 4-5 hours of driving to see/feel/touch/smell any one of the products
on my "list".
> On the other hand, you could find a good used saw and if it
> becomes apparent that it's over kill you can turn right
> around and sell it for what you have in it.
Although that is not out of the question, living in rural area spreads out
the market. If an opportunity presented itself, I would be all over it, but
expecting that opportunity to arise within the next few months would be
unreasonably optimistic.
-Steve
Unisaw A100
>This comming from the guy who's handle is "unisaw A100" ?!?
As an "explainer", A-100 is the serial number of my Unisaw
(El Guapo).
>Although that is not out of the question, living in rural area spreads out
>the market. If an opportunity presented itself, I would be all over it, but
>expecting that opportunity to arise within the next few months would be
>unreasonably optimistic.
Don't forget, there is a proportional relationship between
what you put in and what you get from it.
UA100
Wes Stewart
<smeier-...@primelink1.net> wrote:
|
|Charlie,
|
|Nice reponse. Thanks for taking the time.
I second that.
|
|> DO NOT remove the wheels. That's asking for a ticket to Set Up Hell.
|>
|> While on the subject - you want dynamically balanced wheels - and cast
|> iron at that. Wheel weight = inertia = more continuous cutting power
|> when the teeth hit harder areas. Dynamically balanced wheels mean
|> smoother cutting and that's a really good thing.
|
|What does dynamically balanced mean? Is it like balancing a a car tire?
|(spin it and add/remove material until it's even?)
In my youth I ran an automotive machine shop where we did engine
balancing so maybe I can explain. There are two types of out of
balance forces that can be generated in rotating objects:
Stewart-Warner, the maker of my balancing equipment called these
"force" and "couple", although they are commonly called "static" and
"dynamic" respectively. Usually the term "dynamic balancing" is used
to indicate that the balancing was done while the object was rotating,
but depending on the object, this may or may not be anything more than
hype.
To explain this, I will use a pair of wheels from a bandsaw. Let's say
that our wheels are cast iron and 1" thick at the rim and hub. When
the manufacturer machined the castings, he bored the hole in the hub
slightly off-center and then machined the rim concentric with the
hole. If we measure the runout at the rim with a dial indicator,
everything looks fine; perfectly round and concentric. (From what
I've seen of woodworking machinery, this is not a hypothetical)
First let's use just one wheel and assume that it has a set screw for
locking it on the shaft We place the wheel on the middle of a
perfectly ground shaft of say 2 feet long and lock it down. We then
suspend this shaft horizontally on a set of totally frictionless
bearings located at the ends of the shaft. Since the "meat" of the
wheel is off-center, there is a spot on the wheel that is "heavier"
than anywhere else and that spot causes the shaft to rotate until the
heavy spot rests at the location closest to the center of the Earth.
There is a "force" proportional to the mass and its distance from the
center of the shaft that causes this rotation.
This is pretty intuitive and should be clear to all. We all should
have a feel for what happens when we try to spin this shaft up. At
low enough speed nothing much happens but as the rpm increases, this
weight flying around starts trying to turn our perfect bearings into
junk.
If we go back to our "static" case where the only rotation is due to
the off-center mass we can, by trial and error, drill holes in the
spokes or along the rim of the wheel until we remove the heavy spot so
that when turned to any position and released, the wheel remains
motionless. We have removed the force and the wheel is statically
balanced. Alternatively, we could add an equal weight opposite the
heavy spot and accomplish the same thing. (I used to use modeling
clay to achieve balance and then weigh the clay and knowing the
density of the metal, know how much to drill out.)
If we now bring this shaft/wheel assembly up to operating speed, it
should run very smoothly, thus it is also "dynamically" balanced,
although we didn't spin it up to achieve this. So what's the big deal
about dynamically balanced bandsaw wheels you ask. In a word (or
two), not much, other than it indicates that they *were* balanced.
Where is does matter can be explained by another example: Let's mount
two wheels on our shaft and space them 12" apart. Let's assume that
the manufacturer has implement process controls that have reduced
variability to zero (six sigma). (We won't ask about the off-center
hole bore) So, both wheels are identically flawed. We also assume
that the wheels can be indexed with respect to each other anywhere we
want them.
Unless we routinely win the Powerball, there will be some angular
separation between the heavy spots other than 180 degrees. In any
other case the shaft will rotate so that it stops with the heavy spots
equally spaced about a downward pointing line bisecting the smaller
included angle between them. We now have too little information to
know exactly where the heavy spots are. All we know is that they are
equally spaced with respect to the virtual "heavy spot" and they
aren't 180 degrees apart.
By trial and error, we can rotate one wheel with respect to the other
until we position the two heavy spots 180 degrees apart, where they
exactly counteract each other. Our assembly is now statically
balanced. Are we done? No, let's see what happens when we spin it
up.
Because the two heavy spots are separated 12" from each other along
the length of the shaft, they try to "do their own thing." At any
instant in time one mass is trying to move the end of the shaft in one
direction while the other mass is trying to move the other end of the
shaft in the opposite direction. Unrestrained, the shaft would wobble
around the point midway between the wheels. So when our shaft is at
rest, i.e. static, it is in balance but when it is rotating, the two
forces "couple" to each other and the assembly is "dynamically" out of
balance.
The only way to correct this is to spin it up and measure, and
correct, the forces independently. Note that with a given amount of
off center mass, the effect is worse the farther apart the two wheels
are along the shaft. Conversely, if we slide the two wheels together,
since they are relatively thin, the effect is negligible and our
static balancing method is probably good enough.
Lest anyone think that the static method I describe isn't used, we had
a couple of industrial strength crankshaft grinders that used grinding
wheels 36" in diameter and two or more inches wide. The wheels had a
center hole about eight inches in diameter and were mounted on a hub
that captured the wheel between two flanges. Since the wheels were
molded, the holes weren't terribly accurate and the wheel was never
concentric when mounted. The hub contained a set of sliding weights
and we did mount it to a shaft and put it on a set of bearings and
tweaked the weights just as I described earlier.
When we figured it was close enough to not self-destruct (it happened
once...you think a table saw kick back is something....) we would
diamond dress it round and rebalance.
Since tire balancing was mentioned, if you're old enough to remember
the old skinny tires, you might remember "bubble balancers." These
balanced the tire/wheel assembly statically by suspending the assembly
horizontally on a point and using a bubble level to see which
direction the tire moved. Weights were added on the high side until
the tire was level.
With today's wider tires (the wheels on my Camaro SS are 9" wide) it
matters on which side of the wheel the balance weights are fixed,
especially at 130 mph.
I know this doesn't have anything to do with woodworking but I don't
know much about woodworking so I've gotta write about something else
:-)
Whew.
charlie b
snip
> What does dynamically balanced mean? Is it like balancing a a car tire?
> (spin it and add/remove material until it's even?)
You got most of it right but they don't add weight but drill out
some of the cast iron to get the balance.
> I understand the theory. Do you find that these guides offer a imperical
> improvement, or is it tough to say without a proper control group (same
> saw/blade/wood etc.. with alternative guides)?
The euro guides that came with the LT16SEC had bearings on either side
of the blade which parallel the blade. They've got a relatively large
diameter so the thrust bearing behind the blade can't be directly
behind them. Go here to see the upper and lower guides - second set
of images on the page
www.wood-workers.com/users/charlieb/BandSaw.html
I added images of the ceramic guides just for you.
> >
> > Torben is a bandsaw nut - loves doing laminated pieces using stuff
> > he bandsawed himself. If LT carries a bandsaw Torben probably
> > has used that model. If it doesn't work for him they probably
> > won't be selling it.
>
> Lost you there... Who's "they".
>
"They" = Laguna Tools. Torben is the founder and president
snip
charlie b
B a r r y B u r k e J r .
wrote:
>
>Don't forget, there is a proportional relationship between
>what you put in and what you get from it.
I don't think there is a right answer to this question.
There are also relationships that involve diminishing returns and
opportunity costs.
Tracking down a decent price on a vintage tool can be a hobby in
itself, which some folks greatly enjoy. For that enjoyment those
folks give up the opportunity to use their time actually woodworking.
Spending more money for a new, high-quality tool gives up the
opportunity cost on the money, but returns it in time available to
actually use the thing.
For instance, if I were to spend weekends or time off traveling around
looking at used machines, the money available to me would dry up. If
I continue to make useful things and improvements to my home that my
wife finds beautiful, I keep the harmony when I drop $$$ on a good
tool. She's seen what her friends pay for such improvements, and
understands the value. In fact, some of her acquaintances have
provided an extra income stream. <G>
If I were retired, I would probably have much more time available to
find and restore used machinery, and likely have less money, which
would make finding them more worthwhile.
The key is for each individual to create a balance between the two
extremes that works the best for them, based on the amount of time an
money available. Also, some localities are better for finding used
tools than others.
Barry
Edwin Pawlowski
>
> I know this doesn't have anything to do with woodworking but I don't
> know much about woodworking so I've gotta write about something else
>> -)
>
> Whew.
Thanks, it was an interesting (and educational) read.
--
Ed
e...@snet.net
http://pages.cthome.net/edhome
Poseidon
says it all...
"WD" <wd...@wherevernet.com> wrote in message
news:40129bbe$1...@corp.newsgroups.com...
> On Thu, 22 Jan 2004 16:22:57 -0600, "Poseidon" <pose...@knology.net>
> wrote:
>
> I too am looking for a bandsaw and recently an old 20" Powermatic (I
> think 50's) was avaliable (for 1K) and decided not to buy it as I need
> to sink a lot of time and money into it. I am still debating whether
> to buy a Grizzly 17" or the next size up or maybe a Delta 14".
>
> Please tell me, did you encounter trouble like adjustment, underpower
> or any other problems?
>
> >I recently purchased the Grizzly G0513 17" Bandsaw. It is a 2HP bandsaw
with 12" resaw capability. I just set it up and ran it; however, I have not
had an opportunity to cut anything with it yet. I cannot compare it with any
of the other mentioned saws as I have not used them. I will say that I am
impressed with what I see and am pleased with the purchase. A review of this
saw can be seen at:
http://patriot.net/~stpeter/woodworking/G0513%20Review.htm.
> >
> >-Mike
>
>
>
mail_$
> Good post.
> <snip>
> Although I have not been looking for it, I have not seen the tension spec on
> any of the websites. Do you find that that spec is available from most
> vendors?
I was also wondering about maximum tension. Anyone know what a Delta 18"
can handle for tension?
Wayne