Laguna LT18 Bandsaw help

[Bill ThompsonNM]

Last week I purchased an 11 year old Laguna LT18 Bandsaw ($800!), but a bandsaw with a problem. It fell over (with the previous owner) and landed on the motor, bending the lower frame of the bandsaw where the motor mounts. I looked at it carefully, watched it run and decided it was fixable. Basically the bend has added some vibration, but it still tracks excellent, etc.

So.I can use some advice as I work on it....

I've been working on it some this evening. I first made the assumption that the motor should be perpendicular to the sheet metal of the saw where the motor is mounted. Since my metal isn't very straight, I made it perpendicular to the metal surrounding the bearing for the lower wheel. I'm making the assumption that the motor is very symmetric so the fins should be parallel to the axis of the motor since I can't see how else to set it. Does this sound reasonable?

To get it perpendicular I have about a 1/4 inch shim at the top of the motor and used some 3/16 inch steel bar crossing over the hole for the motor on the backside to bolt the top of the motor to the frame with the shim between the motor mount and the frame.

Now, it appears I need to get the belt pulleys aligned directly one above the other. It's not clear what to use for a reference surface in this case. the pulley walls for the small motor pulley are a different thickness than the same wall on the drive pulley so I can't use a straight edge against the two pulleys.

I removed the blade and powered it up and all of this work has already made a significant improvement, maybe enough that if the pulleys were in good alignment I would be done.

I do realize that the extra bolts and shims, on the other hand will make changing and adjusting belts a royal pain.. since I'll pretty much have to repeat this procedure with any change.

I suspect I may want to make a large bolt on plate with similar mounting holes to fit over the frame mounting section, and then remove any damage material just around the motor mount where it sticks out one way or the other too much. Something like 1/4 inch steel or 0.3 inch aluminum. The aluminum would be easier to machine, but would have to be a little bit thicker for the same stiffness.

Suggestions?

and here's a picture of the saw. I have pictures of the mounting plate, but you can't really see the warped plate.. so not real useful.

[Van Huskey]

I think you are on the right track with the mounting plate.

As for the pulleys, I would measure the width of the pulleys (assuming the walls on each side of each pulley is the same width, I imagine it is) so that half of each width would be the distance from the centerline to the outside face, the centerline is what you want to align obviously. When you subtract the 1/2 width of the more narrow pulley from that of the thicker pulley you have the difference between the two pulleys distance from the outside face to the centerline. Then you need to come up with a way to offset the straight edge by that amount. Not knowing the difference it is impossible to guess what materials might work but wraps of masking tape pulled tight could get you close then wraps of cellophane tape for the last bit would probably work well. Then use that part of the straight edge up against the more narrow pulley to make up the difference and you should then be able to align the centerline.

As for the pain of changing or adjusting the belt, it doesn't happen often and when you do you can just think about all the big money you saved. I might slap a new belt on it to significantly prolong the pain of replacement.


BTW great score, YOU SUCK!

[Jim Matthews]

Having a larger width pulley driving should help you with misalignment problems, so long as it has a "Vee" channel.
If the rims are square, misalignment will lead to fraying and the belt will eventually twist off.

This shouldn't damage the machine, as it will stop the drive motion.

SO - if you add a wider drive pulley, and can't get the exact length of the belt you need, use the Power Twist V-belt (http://www.amazon.com/Powertwist-Power-Twist-V-Belt/dp/B001BQDS8I).
These may not have the same grip as a standard drive belt, so you'll give up a little maximum torque.
If you change the diameter of the drive pulley, you'll change the feed rate on you saw blade.

Again, that might not be appreciable, if your replacement is close. Make certain to use a keyed spline with a fixation, to keep the replacement attached.
I wouldn't want something that massive working it's way loose, at speed.

I have to ask; how do you knock something this big on its side? Did the previous owner hit it with a garage door?


Jim
Westport, MA

[Bill ThompsonNM]

I did ask how it got knocked over, he said it was too painful to discuss! It was in a shop that made trim. Sort of their auxiliary saw . They also had a 36 inch Meber? Saw for sale along with a 20 inch powermatic. They were keeping only a laguna lt24. Getting most of their wood sized and sawn from the mill now.

[Bill ThompsonNM]

Van, the motor pulley is symmetrical but the drive pulley has a larger flange where it seats next to the saw wheel. You have given me an idea though, I could probably mark the belt and use the mark to measure the offsets and build my straight edge. Ultimately I still am considering a steel plate rather than all the shims-- maybe Bruce Page can suggest a machine shop in Albuquerque they have all closed down locally. I probably could do an ok job machining an aluminum plate with my drill press and a hand grinder, though.

I watched CL for quite a while, never figured I could afford a saw like this. Luckily I had the $ and the owner held it for me on good faith over the holidays despite other offers since it was a 4 hour drive and too much snow and work.

[Mike Wilkins]

I have that same machine, and for the price you stated, you got a steal, you lucky bum. From the description on your repairs, you are on the right track. You may be able to move the pulleys right or left to get a proper alignment, but even a slight misalignment will not affect the smoothness of running or the blade tracking.

[Bill ThompsonNM]

Thanks Mike, for the encouragement. For the record, btw, when I got to Mancos, Colo ( add that to your CL searches everyone) the owner pointed out that he did add the mobility kit and had recently upgraded to the new Laguna ceramic guides. After we were getting ready to load it into my wife's Dodge Caravan, he rummaged around some more and gave me a total of 14 blades, 12 used but sharpened, two brand new and a Laguna Resaw King!

I also have to give kudos to the Laguna tech support, I haven't bought anything from them yet, but they've been very gracious, accomodating and helpful both before and after I purchased this used saw. I know they've gotten some bad publicity on occasion but they've sure impressed me!