Thread: Trouble adjusting saw

I assume you have been using this saw since you got it last Sept, did the demons just arrive?
The first thing I would do is unplug the machine and spin the wheel by hand with the blade removed and see whats going on, sounds like the tracking is way out of whack. Bet the BS just needs a good tune up, did you ever get the books that were recommended to you last year?

Heather

Unfortunately I haven't been able to afford the books, and the local library can't get them for me, which is a bit of a blow.

The thing is, with the old blade, I could cut fine with it. Perhaps when the blade broke it threw the wheel out of alignment?

As far as the back bearing is concerned, I only nopticed the jamming problem when I put the new blade on, when I had to adjust the bearing and thus retighten it.

Cheers,

Dave

i just purchased the same BS and it is running very smooth (very happy with the purchase). as far as books go, there is so much information on this forum and other sites that i dont really see the need for it. i did a lot of reading before i bought the saw and i am really surprised with the amount i have picked up.

if i were you the first thing i would do is take turn of the machine, take the blade off and see if anything is loose. if everything looks ok then put the blade back on and tension it up. turn the top wheel by hand and adjust the tracking accordingly. next, check for coplanar. if you still have a problem then maybe it is the balance on the wheel, but, if you have only had it since september i dont see how the tire could wear out so much... unless one of the weights have fallen off. i dont know how to deal with the issue of balance so cant help you there and i dont think i have seen it addressed in the forum. if anyone has any ideas i would like to know too (it will happen to me sooner or later)

as far as the upper guides go, do you have a picture of what you mean (im not very good with descriptions...).

cheers,

gabacus

Hi Dave,
I've had my Carbatec 14" model for a bit over a year now, and have nothing to complain about. I've broken 2 blades, (one was 1/4") and I have 3 sizes of blades. I've got quite good at changing them and tracking them. Spin the top wheel by hand and you'll soon get the hang of tracking. The blade must stay sitting neatly in the middle of the tyre as the wheel turns.
If that fails, why not go back to Carbatec for advice? The folk in their Auckland franchise are wonderful, and I'ld be surprised if the level of service in Aus. is any less.

With best wishes,

ROB NZ

If you like I could drop in and have a gander, I have the bigger brother of your saw and pretty well know them inside out now. If the weight has fallen off, it's not to much trouble to rebalance the wheel.

In lieu of hard-to-find actual books, Russ Fairfield has two excellent treatments on bandsaw tuning and use:

http://www.woodturnerruss.com/Bandsaw-Tuning.html

http://www.woodturnerruss.com/Bandsaw-Using.html

For more orderly file management, use "Save as" *.mht if available in your OS. (All in one file)


Tony Ward also has a huge bunch of links on bandsaws:

http://www.tonyward.org/index.php?op...d=38&Itemid=90


Joe

Thanks all for the input.

DJ, if I can't fix the problems myself with what I'll now be reading, I'll take you up on your offer.

I'll also post a pic of what I'm talking about re: the bearing.

Cheers,

Dave

NOTE: WHENEVER YOU NEED TO CHANGE BLADES OR REALIGN BLADES DISCONNECT THE POWER TO THE BANDSAW AND REMOVE THE DRIVE BELT.
Bandsaws are temperamental when you need to change or install blades. They do not always track correctly and so it is necessary adjust the top wheel to suit each and every individual blade. Most times it is just turning the top screw to put tension on the blade and then turning the side screw to bring the wheel in or out to track the blade. The is another adjustment that may be called upon to get the blade to ride the centre of all the wheels. It may not be obvious to new owners but the bracket that holds the top wheel and springs can be twisted in or out to change the angle alignment of the wheels. You should find that the bracket is held in place by two bolts. Loosen the nuts just enough so that you can twist the top wheel left or right ever so slightly. Install the new blade, put tension on the blade, turn wheel by hand and watch how it track. As necessary twist the wheel left or right and watch the effect. When satisfied it will run true, tighten the nuts and bolts on the top wheel bracket. Adjust the blade guide rollers to just touch the back of the blade. Refit blade guard and insert and adjust guide blocks.

ALSO
Some blades can be rejoined by silver soldering or brass brazing.
I have joined one blade 8 times before I disposed of it. Main problem with joining is that the blade gets progressively shorter if you blow the metal with intense flame or you cut and file the blade to overlap for soldering. I have gotten around the cut and file by using brass brazing rod and butting the blade rather than overlap. I just leave a hair’s width gap for the brass to flow and join the blade. I have also used a too short blade for one bandsaw on a smaller model bandsaw and so have gotten more mileage out of the one blade. Some blades are faulty and cannot be repaired effectively. I have had blades that have not been tempered correctly and cracks are evident at various spots long the blade when attempting to rejoin the blade.
Some blades have not been joined in the correct alignment and you can observe that the blade wanders in and out against the rollers as it rotates around the wheels. It is most important that when you rejoin a blade that a straightedge be used to ensure the back of the blade is aligned straight.

I've had a bit of an epiffany. My old blade that broke was a 3/8", 6tpi blade. The new blade I got was a 1/2", 4tpi. Could part of the problem be that the blade is simply too big for the saw, contributing to the wonky cuts?

Dave

Originally Posted by yeoman

I've had a bit of an epiffany. My old blade that broke was a 3/8", 6tpi blade. The new blade I got was a 1/2", 4tpi. Could part of the problem be that the blade is simply too big for the saw, contributing to the wonky cuts?

Dave

As long as the blade sits well within the rubber crown on the wheels it should be suitable. 3/4" might be stretching it, 1/2" doesn't seem large.

When having troubles like this with machinery, work by a process of elimination. The first thing I would do is get the top and bottom guides out of the way, slacken them right off so they are nowhere near the blade, then start adjusting tension and tracking. Do it with power disconnected as already stated, and spin the wheels fast, by hand. Once you are sure there is nothing untoward happening with alignment of the wheels etc, introduce the guide setup, one at time, and get the clearances right.

Cheers,

Originally Posted by Linden Hardy

NOTE: WHENEVER YOU NEED TO CHANGE BLADES OR REALIGN BLADES DISCONNECT THE POWER TO THE BANDSAW AND REMOVE THE DRIVE BELT.

I completely agree about the power disconnection, but why would you want to remove the drive belt every time you change blades?? Only having 1 bandsaw, I change the blade for almost every job, easily 2-3 times a day (or more) when doing different jobs on the b/s, and wouldn't want to remove the drive belt every time! Given that once you have tuned your bandsaw, the lower wheel stays put relative to the drive pulley and lower axle, what possible gain by removing the belt - the top wheel has all the adjustments required to cater for each different blade.

Originally Posted by yeoman

The upper wheel seems to be unbalanced, making the wheel girate as it spins, which gives a blurry blade, and a wonky cut. I'd try and fix it, but the wheel spins so quick, I can't see which bits need the weight.

Just on that point Dave, one of the books refers giving the wheel a spin by hand (without a blade, and power disconnected), and marking bottom dead centre when it stops. Rinse and repeat a number of times, and if the wheel is unbalanced, you will start seeing a grouping occurring with the marks. After a while, you will get a very good idea where the wheel is too heavy (or opposite those marks, where it is too light).

If the marks are all random, and no trends appear, then the wheel is probably pretty well balanced.