I bought a 14" Powermatic band saw a little over a week ago. I'm not that
familiar with it yet. Today I picked up a 3/4" blade on sale at a local
lumber supplier. I tried to install it a little while ago but ran into a
few issues. It went on fine, or so it seemed. The lower bearing that
rides at the back edge of the blade does not seem to have enough travel to
allow the blade all the way in. It goes most of the way, but it does not
seem possible to set it according to the owner's manual. In other words,
it will always be touching the back of the blade and it touches it pretty
hard if you know what I mean. To complicate matters, that bearing doesn't
spin freely anyway. It's too stiff to spin like the rest of the bearings.
I will tinker with it and replace it if necessary, but the travel issue is
still a problem. The combination of the two problems resulted in a
slightly hot bearing with a slight groove beginning to wear in the bearing.
This was after a short test run.
Questions: Should I pull the blade off and just accept that a 3/4" blade
simply won’t fit even though it is supposed to fit? I seem to remember a
recent discussion saying that fitting a 3/4" blade on a 14" saw is a common
problem. I sure did like the result of the test run I made. Are there any
adjustments that I am missing that would remedy the problem? Anyone
familiar with this saw enough to tell me what I need to know to run a 3/4"
blade in it?
On 6 Jun 2005 11:54:12 -0700, email@example.com wrote:
I did think of that. How do you know I didn't email them as well as this
newsgroup? I can be a wiseguy also :) But seriously, when I think of a
place to look for a broad range of real-world experience with woodworking
machinery, I think of this newsgroup, not the customer service rep at a
large corporation. I'm sure their help is great, but sometimes I like to
mine many sources to arrive at a solution that works for me.
Thanks for the input,
Well, you might have been able to move the blade forward with tracking, but
if you're doing all right with other blades, do without. I've a Delta, and
it does fine with the 3/4 blade, especially the thin one from Suffolk.
Never have been able to figure out why, if the upper thrust bearing was on
an eccentric, the lower wasn't. Can lead to those kind of problems you
mentioned if the blade was too far inside the rim, even if the bearing spins
like a sweetheart otherwise. Remove and reverse the bearing, though you
still might want to bitch and get another from Powermatic.
I did try to move the blade forward with the tracking, but it was too far
forward to be safe or practical by the time it wasn't touching any more.
It was already pushing the limit of being "centered" when it was rubbing
against the bearing. I'm still tinkering with it. I may have found a
solution. I'll post it if I do.
If the blade is riding where it's supposed to be, remove the table and
adjust the lower guide mounting unit. It is attached to the frame with
bolts--loosen the bolts and move the assy back. be sure to keep it
aligned with the blade so that the side bearings are still perfectly
parallel with the blade. I had to make this adjustment when my BS was
Brian Mahaney wrote:
I had to leave right after I wrote my post yesterday, but when I got home
last night I was able to get a closer look at the problem. Taking your
advice, I pulled the table and examined the lower guide. Sure enough it
had quite a bit of adjustability. However, it was already adjusted back as
far from the blade as possible. I loosened the two bolts that hold the
assembly in place and pushed back on it just to make sure. It wouldn't go
back any farther. I was able to see why the bearing wasn't spinning
freely. When it is adjusted back as far as it will go, it rubbed against
the body of the unit. It was touching just enough to cause a little
friction. The bearing still turned, but not enough to let it spin at the
same speed as the blade was traveling. So a small mark (I'll call it a
scratch) was formed all the way around the circumference of the bearing.
In order to buy a little space (not much was needed) I filed a couple of
thousandths of metal from the area where the bearing was rubbing.
Additionally I filed a couple of thousandths from the area where the
mounting bolts go to allow the whole assembly to move back just a hair
more. This did the trick. I bought just enough room to allow the bearing
to spin freely. However, I would like the blade to be a tracking a little
closer to the center of the wheel. It is close, but not where I would put
it if I had the ability to move it farther back. Also, when I move the
blade by spinning the upper wheel, the blade touches the bearing more often
than not. It's just too close to be how it's supposed to be. I've
actually considered tapping new holes to mount the assembly. I could
easily mount it closer to the center of the adjustment range. Don't know
why they didn't do that in the first place.
Thanks for the advice. I'll post the ultimate solution when I arrive at
Brian, I'm glad to hear you were able to run with my suggestion on the
lower guide assy. Sounds like on mine PM didn't secure the guide assy
in the exact spot they should have, and in your case they may have
drilled the holes off their mark. As I remember, I had to move the assy
all the way back, so any slight error on another unit's bolt holes
might require some machining.
Once you get over this problem, I bet you'll really enjoy the saw.
Using my BS yesterday a lot, I congratulated myself for buying it, after
a disastrous 1 week of owning a Delta. I esp love the blower and light.
Oh, I find that the 1/2" (or is it 5/8" - I'm not sure) blade I use is
sufficient for the big cuts. Many books suggest NOT installing a 3/4
blade onto the 14" "Taiwanese" BS, due to the heavy tension needed.
Brian Mahaney wrote:
I decided to try the 3/4" on a whim because I found it on sale. I already
had a 1/2" on order. If it cuts as good as this 3/4" is cutting, I'll just
leave it on for most cuts. I do like the saw. Even with the cheap blade
that came with it, I like it. I'm even enjoying the light and mobile base
that I got with it. I'm normally a no frills kind of guy, but went above
and beyond for this one.
That reminds me. My wife made me promise to gloat about her because of her
tool policy. She said I could only purchase this band saw if I extol her
virtues to the world so here goes: my wife's policy for tools is that I
should always get the best I can afford. She makes me buy the more
expensive one most of the time because she says, "I don't want to hear you
bitching that it isn't good enough." So, little by little as I can afford
more, I go for the best I can find that will fit in my tiny shop. There it
is. I see a new tool on the horizon for this.
:) Your wife attitude sounds identical to mine! She's prodded me into
buying a bit more than I'd planned on. She's ordered a number of gifts
from LV for me. The only tool I'm having trouble convincing her I
should get is a drum sander. Father's Day is coming up, and for that I
suspect there will be some more LV goodies! Xmas always nets me a few
LV goodies too. Gotta love her!
What size is your shop, Brian? I see you say it's "tiny". Mine is in a
2 car garage and I wish it were at least 3 times that size so I'd have
more room for stock, another workbench, and dedicated tall and short
assembly tables. But hey, I'm still having fun with what I've got.
Brian Mahaney wrote:
Now there's an idea. Elegant. Simple. Reversible. I like it. Might try
it. I'd use machine bushings. They are more likely to be the same
thickness. This sounds easier than drilling and tapping.
Brian, granted PM may have drilled the holes incorrectly for the lower
guide, but they have the geometry correct for the wheels. I already
tried making the wheels coplanar; it won't track correctly.
Brian Mahaney wrote:
Don't do it on a powermatic! I tried that after reading about coplanar
theory. The unit is designed correctly and tracks all blades perfectly
without being coplanar. I put washers in, thinking I was smarter than
the mfgr, and fired it up with a wide blade. No good. Removed the
washer and all my blades track well.
Hmm, were the washers the same thickness? Those things are stamped out of
what ever thickness they have on hand. They vary greatly even when they
come from the same box. That's why I would try machine bushings. Any
other experiences with this sort of thing out there?
I can't remember exactly how much I shimmed it, but I think it was about
a 1/16. It put the 2 wheels into the same plane, but it didn't track
with a damn. Because of the tracking adjustment, it's not as simple as
just aligned the two wheels with a straight edge.
Bottom line, if your blade tracks well, you shouldn't need to "improve"
the design with shims.
Brian Mahaney wrote:
That's what I thought. After all, I wouldn't be attempting to change
anthing except how far out the wheels are. Using the same thickness of
machine bushing would maintain that geometry. I haven't even had a chance
to look at it, but I may do so tonight when I come home from work. Maybe
he's right. Maybe there is something else there, but it sure seems like a
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