MM20 ownwers...quick question..

[Barry Londrigan]

I have a quick couple of questions for anyone who might be able to answer it.

When the tension is completely removed from the blade, should there be any "rocking" of the upper bandsaw wheel when you grip it like a steering wheel and rock it back and forth? I can move mine back and forth like a 1/16th or better. (The bottom wheel cannot be moved at all) In other words there is play in it. I am sure this tightens up when tension is apllied to the blade but just curious.

A while back I was cutting something on the saw and I had a very wide blade on it (I think it was the max at 1.5") Anyway, I also had the plastic guard on the saw. I finished the cut, hit the stop button and was letting the saw stop on its own when the blade grabbed the plastic guard and with a loud bang blew it to pieces. Other than the guard, the only other thing I noticed was the flat black triangular piece at the bottom of the guide post was bent from the force. It was slightly angled downward. The plastic guard (which is not on this picture) attaches to the front of this and when it happened, it bent it slightly. I had to remove it and hammer it straight. I have enclosed a picture of a saw (not mine) to show the piece I am talking about.

Other than a big scare and then a little humiliation for not noticing how close the guard was to this wide blade, I was lucky not to have been hurt. A small piece of plastic actually stick in my hand as it came apart! I had that deer in the headlights look for a while.

I am just checking my saw out which is cutting fine as far as I know.. (I have barely used it and really did not have a lot of experience with it and therefore don't have a lot of example of what to expect) I am going from memory (which gets fuzzier all the time!) but I thought I recalled when I first got this saw that there was no play in the wheel at all but I might be recalling improperly... so I thougth I would ask youze guyz!

Thanks

Barry

[Gary Herrmann]

I don't think you should be able to rock that upper wheel back and forth. I'd call MM and ask to make sure tho. I would think that "looseness" could make the cut wander and potentially put stress on the belt and motor pulley.

I've got an MM16 and mine does not move.

[Roy Wall]

Without tension, my upper wheel will "rock" about an 1/8" or so....

[Barry Londrigan]

OK...thanks for the replies guys. So I have investigated a little deeper and this is what is happening. (I have taken a picture of this as well). In the picture you can see the "boss" that holds the shaft and bearing(s) for the wheel. You can see that it slides up and down in the "way" at each side when tightened or loosened. It is happening because of slight slop in the way that the boss slides in. I am pretty much guessing that this is not a result of anything that I did when I broke the guard. This is just inherent in the saw. Would you agree? BTW...how do you like all that rust on this beautiful saw?? Yikes!

I wonder what the two Frankenstien adjustment bolts are on the sides of the adjustment assembly?? Anyone? Anyone? Ferris?

Barry

[Richard Wolf]

It is the tracking adjustment that will cause the rocking with a blade off or with very little tension on the blade. I don't think you should remove so much tension, the blade may move off track and when retensioned it may be out of position.

Richard

[Barry Londrigan]

Richard,

I am not sure I understand what you are saying. Are you saying the two bolts are the tracking adjustment or are you referring to the actual tension adjustment? I have not adjusted on the two bolts...

[Richard Wolf]

Barry, we were typing at the same time, so I was not in responce to your statement about the boss. I am not at my shop to check mine, but I would think that when not under tension to wheel would be free to move back and forth trying to track. The tracking adjustment will only push the bottom of the wheel forward.
Ofcourse if you found slop in another area, that may be the cause. I will check mine tomorrow, if you don't get the solution.

Richard

[Barry Londrigan]

Thanks Richard. I took an even closer look at this from over top looking down inside. There are two holes at the top of the saw for access. These two bolts are meant (at least that's what it looks like to me) to keep side slop out of the tracking assembly. I would assume to also center this whole wheel assy.?? I also checked it further and it appears that the slop is ONLY in the "way" as I have described. This is for all practical purposes, a brand new saw...maybe on hour on it. When proper tension is applied to the blade, gripping the wheel at 12 and 6 I cannot rock the wheel at all. At 3 and 9 I can ever so slightly rock it but there is tension on it. I am beginning to think I am just paranoid because of the guard fiasco! BTW....do you use the guard or is it removed?

[Richard Wolf]

What guard?:D:D

Richard

[Jeff Wright]

....do you use the guard or is it removed?

My MM20 is one of the more recent ones and I am told by MM that the clear plastic guard is no longer installed on the machine. Mine did not come with one.

[Barry Londrigan]

Exactly! So I will have to do some sawing here soon to see how well this will resaw (without wandering) and will wait for any other replies in regards to a little slop in the adjustment ways for the wheel assy. I forgot to mention a thanks to Roy for letting me know I may just be paranoid. So Roy...how does your saw saw ...sea saw by the sea shore? :) Wander any or do you have a smoot cut upon resawing?

Barry

[Roy Wall]

Barry,

The most resawing to date is only 6-8".....so no problem for the MM20.

I have the newer model and yes.......they have done away with the plastic guard in front. I track the 1" blade with the gullets about half way over the front edge. 1/2" blades and smaller are tracked in the center of the wheels.

I think I'd be a little gun shy also.... Since the saw was "spinning down"....my guess is the harmonic vibrations blades give off may have caused enough wobble to cause the problem. Was the blade still properly tracking on the wheels after this episode?

For getting back on the horse (as they say) - I think I'd go thru the "hand spinning to get the blade tracking well - then just start the saw for an instant (staying back) and let it stop, check the tracking....then start it up again if all is well--run for a minute -- power off - check again.... just to make sure before I cut again.

Be safe!