Wood-Mizer LT40 - Critical Failure 

Looks like a new mill. I suggest the following; 1. I believe the blade came off because you reversed the carriage with the blade engaged. 2. Make sure you did not hit metal 3. Your blade tension looks good; check your drive belt tension. Your manual will tell you how. You should also find the tension test tool in the manual also. The number 1 reason for wavy cuts is a loose drive belt. Good luck Dave

You hit metal, when your dull your start dipping and diving..... another day in the life of a band mill lol keep the videos coming! God bless

Well I see I’m not the only one who has had this problem now.. this has actually happened to me a lot. These dang sawmills ain’t near as easy as these boys on RU-vid make it look like! I’ve been getting curvy cuts since not long after I got it and I’ve talked with woodmizer about it and we’ve narrowed down that my blade tension isn’t right so I have new parts here to fix it but haven’t had a chance to do it yet so I don’t know if that’s really the problem or not

everyone here pretty much nailed it. But metalurgy 101; as you run a new blade it heats and cools and eventually stretches. As one commenter stated, you have to continually watch your tension. The sparks could have been the blade coming into contact with the guard as it jumped and slacked. There are a lot of moving parts with the horizontal band saw. I dont like them because you're asking a lot of it doing large material. Your width guide adjust needs to match the stock your cutting too, if your wide, it will bounce and you can get the dips and waves as well. Keep playing, eventually you will become smarter than the tool.

Somebody was saying on there about adjusting the tension on that ban that’s in there I used to work with a lot of these kinds of machines matter fact they do that here in northeast Tennessee. It’s a really good machine to have. It’s got its pros and cons you got a watch when you’re doing telephone poles with it did you pick up nails and stuff and I’m more people than posting stuff but you’re usually cutting the first and you’re so off around them anyway, but those are great when you need to do a barn the outside part anyway, you don’t wanna be walking around and barefoot on that creosote

I have never operated one, so I have no idea unless just possibly the blade tension became loose. I have heard it said that there are two types of sawmill operators: 1) those who have cut into a saw dog and 2) those who are going to saw into one.

Appears to be no fluid running (blue reservoir) None visible in the line or on the cut. Either forgot to open the line or its blocked for some reason.

Im wondering since it was a brand new blade maybe it got warm and stretched, you might have to go back and check your tension after every couple of cuts till the blade gets seasoned a bit. as for the sparks, if they came out of the log, then possibly an old fence wire or a nail, but if the sparks came from the pullies then it was probably from the blade coming off.

Looks like the blade was loose because it dipped from the beginning. Like somebody said the blade will heat up and stretch. The sparks could have been because the blade was twisted too much for the rollers and guides.

Man that thing is so cool. I know for metal if you get to moving to fast to much pressure on blade it can walk with you and not cut straight. Not sure if your set up will do the same.

Coulda been some kind of bow or twist relief cracking it. Sparks typically mean metal in the log

You hit a nail

That really sucks. Hopefully you or someone figures it out. Good luck

I have never run one but I have worked at saw mill a lot I see a little dark place on the log where it mess up

Anytime I see sparks it’s always, a nail , bolt, bullet something not good: happens a lot to me I cut lots of utility poles . But the way your blade was wavy at the beginning might be blade tension or a dull blade that will do it. I bet you put the correct tension and a new blade and your good to go

Never reverse the saw while the blade is engaged. That's why your blade jumped off. My guess is it dove because you hit hardware in the log

The saw blade contacted metal. The blade dulled on one side and took a dive because it was cutting faster on one side than the other. It happens now and again because people use trees for fence posts or just drive nails into trees. In any case you should not try another blade on that cut. Sacrifice the wood and use a chain saw to cut down where the saw stopped and inspect the path of the blade.

No big deal, gust hit metal ,and backed it out pulling the blade of the wheel. Make sure guide bearings are aligned and working good, also blade is aligned and cutting straight.

You might have hit metal. That would explain the sparks. I have also had issues with pine logs especially if they have been sitting around a while and are dry. Pine cuts best on the mill when it’s really green. I have more issues with pine wandering than any other type of wood. Also check your blade that it is perpendicular to your bed. I lay a 18 inch piece olof angle iron across the blade when it’s at full pressure and measure the distance on both ends of the angle iron to the bed to make sure the blade is level.

Tighten your blade tension to the 5 o'clock position.make a cut then check tension again.tension should stay in the 4 to 5 o'clock position.mix pinesol with water lube to help keep the pine tar off the blade. I'm pretty sure you've hit metal in your cant also.

No expert but it looks like the belt was not tight enough.

Drive belt good video

Yeah you broke it bad now it’s ruined. I’ll give you $100 if you deliver it to Tennessee 😂

When I cut a lot of cedar I have to worry with nails in the log. Some of the pine is so hard I have to lubricant the blade with soap and water

A dull blade will cause wandering. A bent blade cannot be used again. Dirty logs will dull blades fast. Sparks happen when hitting metal or the blade jumping off wheels and hitting other metal on the machine. This from my personal experience with another brand of mill. You can cut the cant at the end of your cut to see if there was metal in the cant. If not, it is either a dull blade or poor tensioning and it looks like your tensioning should have been ok from your video. How long were you cutting when this happened?

acted like hit nail especially with sparks possiblely rock suggestion ues a wedge or shim to spread the cut so release pressure on blade

I hope their wasn't a nail or wire or something in that log . I would take a chain saw and cut that piece off and inspect the log where it messed up ! Had to have been a foreign object in the log, Let us know what you find . God Bless !

Nooice! 😎 STOC

Your blade looks dry. Is it being lubricated? Like you, I'm no expert with these machines. I've just watched lots of youtube videos too. Good Luck.

Ours we have water and soap that drips on the blade to help that issue

I agree with the Old Man....

did you ever find the answer?

Look for a dark spot

Metal? Or loose blade?

Sounds like you hit metal

Hmmm….any way to ask for a competent/experienced operator to come and show you proper operation? It could have been a speed issue? Maybe cutting to thick of stock, pinching the blade?

By the way the blade some times does that when it dull

I am no expert but saw blade not tight enough and going to fast maybe put a wage on that thick of cut like that

You probably got a nail or something in the log. The blade can be resharpened and reused

Sam pa nađi nekoga da ti pomogne.

metal in the log causes sparks. was there a black mark in the end of the log?

Not a critical failure. You probably hit metal, blade popped off because you were in reverse, nothing to hold the blade on the guide wheels. Good luck with the Yanmar engine.

It takes more than a day to learn. Talk fto Dutch

Going to fast you've got to go slow check your log could have hit a nail are you running water on the blade keep messing with it and you will learn I've saw a lot with one call a wood mizer

Metal in tree..bigger than a 20 penny nail

Looks like dull blade to me

No experience here. Just a RU-vid jockey. Sparks mean metal to metal. The wavy cut could be from too fast of forward speed. That’s what happens on my metal bandsaw if I go too fast.

YOUR BLADE WAS LOOSE, YOU GOING TO FAST, YOUR BLADE GUIDE IS BENT, THE BLADE IS BURNT AND TWISTED/BENT WHEN THE MACHINE IS OLD THE BARREN ON BLADE WHEELS WORN OUT AND OR LOOSE