Mill, 1997 LT40HD24
Problem. All of a sudden the pressure gauge starts jumping by a couple hundred pounds and the is a noticeable vibration of the sawhead.
History, everything fine til I sawed some really sticky pine, had a lot of trouble with sawdust build up under the belt on the powered band wheel, more than I have had since I bought the mill new. Now sawing oak, still getting some build up occasionally, never had that before.
Trouble shooting, changed blades several times, changed bandwheel belts, grooves are clean. Spin off side wheel by hand, bearing seems good, no sound. Take blade and belt off, put motor in gear, no vibration on the saw head. Take drive belt off and spin by hand, sounds fine.
The only thing I have found so far is the drive belt, looks new, it is the notched belt, about half of one notch is gone, hard to believe that is the problem.
Haven't had a chance to call WM yet. Anybody have any ideas?
What about the adjustment of the blade scraper in front of the blade guide roller?
It has clearance.
First thing, it sounds like a cracked saw, but you have tried several with no change or pitch under the belts and you have addressed that as well. Check for cracks in the wheels. Can you see a vibration in one wheel or both or in the drive belts?
It still sounds like there is something under one of the tires. If the pressure gauge is the one for the band tension, then it is moving because the tension is changing. That is indicative of the idle side wheel being moved, such as would happen if the band was traveling over a hump. When there is something under the band-tire, there is usually an accompanying roaring sound.
Wipe the V-groove down with WD-40 or something like that, in case the sides of the groove are sticky.
Check both the power side and idle side grooves for a buildup. Use a screwdriver and run it along the bottom of the groove as you turn the wheel. It doesn't take much.
swap band-wheel tires one side for the other.
Backwoods, I have not looked for cracks in the wheels, I will do so.
Tom, It is band tension gauge , I read your tutorial of "Let the Bandmill Roar". I used a paint scraper. The grooves seem to be clean. The one thing I have not checked is cleaning out the drill, balancing, holes to make sure they are clean.
Grab the drive whel and give it a good shake laterally. If the bearings inside the carrier have let go it might be causing the drive wheel to whump around in an elipse pattern causing the blade tension to go up and down. MIne lasted 3800hrs and would have lasted longer if all of the oil had not snuck out.
DTR
I think amberwood has it.
I believe it's the main drive bearing.
I would also put a band on and close the top sheild (for safety), put the mill in gear and go around
so you can watch the wheels and the band and check to see if any of your vibration is visible.
Sounds like you have something under the belt or in the grove. If the tension gauge is moving the blade is getting tight and then loose.
If you need to check the drive bearing, the brake needs to be released and the drive belt also needs to have no effect on the bearing. Pull the clutch engaugement mid way to check the bearing. I would think if the bearing was loose the blade tracking would be effected.
Marty
Check for sawdust building up in the balancing holes on the driver band wheel. If you find any be sure to clean the holes completely. It's not that the sawdust causes an imbalance -- it collects more sawdust and making a bump under the band.