I recently bought a Timbermule bandmill. It's made by a local company. It runs large pulleys instead of tires 13"2" blade. Anyway so far I've milled seasoned red oak without any problems. Today I tried milling green sugar maple. Every time I would come to a knot or a crotch the blade rises up and makes a thick spot in the board. I put on a brand new blade today, and tried to push the mill head with an even speed. What else could cause this problem? My only thoughts are the idler rollers I'm not for sure what angle to adjust them at. Thanks!
Getting wavy boards, New to Milling!
- Thread starter Musclenut
- Start date
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Are you using 1 1/4 inch by 0.042 blades? How much tension or is it just so many turns of a screw? How much does the rollers deflect the blade from straight? The rollers should be so the part that touches the band is parallel to the top of the bunks. Does this local company have an owners or operators manual?
I'm the second owner, no luck contacting the manufacturer. It has a screw tensioner with a 20hp honda. Running a 1.25x.042x7/8th Woodmizer blade.
I tried the rollers in different positions. What angle should the blade enter the log?
I tried the rollers in different positions. What angle should the blade enter the log?
I do not know what you have, at least at this point. The blade should not be on any angle as I put in post #2.
If you totally raise the rollers and lower the head on top of a bunk frame member the blade should be parallel to the bunk and then the rollers should deflect it down somewhere in the 1/8 to 1/4 inch range. If it has some sort of moveable blade guide on one side that has to travel so the roller blade assembly stays parallel to the bunk as well.
Do you have rollers with a shoulder or one behind and one on top and bottom or what? Mine has a hydraulic buffer sort of thing that reads out the tension. I would have to read the manual to see how many turns if it ceases to work. I might be wrong but I think it takes about 7 cranks and who knows if our thread pitch is the same. I would start with the deflection the rollers create and getting them where they belong if that is not the case.
If you totally raise the rollers and lower the head on top of a bunk frame member the blade should be parallel to the bunk and then the rollers should deflect it down somewhere in the 1/8 to 1/4 inch range. If it has some sort of moveable blade guide on one side that has to travel so the roller blade assembly stays parallel to the bunk as well.
Do you have rollers with a shoulder or one behind and one on top and bottom or what? Mine has a hydraulic buffer sort of thing that reads out the tension. I would have to read the manual to see how many turns if it ceases to work. I might be wrong but I think it takes about 7 cranks and who knows if our thread pitch is the same. I would start with the deflection the rollers create and getting them where they belong if that is not the case.
Hopefully someone else can comment. I have not done a lot but the oak was more problematic than maple. I increased the deflection to 1/4 inch and use the lenox chip sweep blade and didn't have any problems lately. One time a chesnut oak somehow made the blade dive and the knot itself was still farther down in the log/cant.
Dave Boyt
ArboristSite Guru
Rollers should push down on the blade slightly (about 1/8" to 1/4"). Try slowing down as you go through the knots. The blade is designed for rip sawing (with the grain), but has to crosscut its way through the knots. Consistent pressure is more important than consistent speed. You don't want to lug down the engine. An often-overlooked source of waviness is a loose drive belt. If it slips, the blade speed drops, and will wander. The blade angle should be dead-level with the track. What hook angle are your blades? A lot of people use 4 degree or 7 degree for hardwoods, which is less aggressive than the usual 10 degree angle. Finally, run the mill like a chain saw-- full throttle all the way through the cut. Hope there is something in here that solves your problem! I cut a lot of oak on a Norwood band mill, and the knots can be challenging, but once you get a feel for it, you should be able to cut straight through them.
betterbuilt
I build stuff from milled slabs
I can't tell from the picture. Is there one of those tanks that drips water on the blade?
Cody Colston
ArboristSite Member
I would advise using band lube. Excessive heat kills band blades and will make the band expand which reduces the tension. Lube will keep the band cooler, make it slide easier through the log and reduce sap build-up.
Lots of different lubes used, from plain water to diesel fuel. I use water with a couple of glugs of dishwashing liquid added. When sawing Pine, I add a few ounces of Pinesol to the lube mix.
Lots of different lubes used, from plain water to diesel fuel. I use water with a couple of glugs of dishwashing liquid added. When sawing Pine, I add a few ounces of Pinesol to the lube mix.
SDB777
I find unique timber and cut it up
With Cody on this one....
I use a few ounces of Pine-Sol in 5 gallons of water, plus a few drops of cheap dishwashing liquid stuff. Pine or hardwoods get the same mix just to keep things simple. A dirty band is a band that 'drags' going through timber, dragging equals wavy.
Scott (diesel gets expensive) B
I use a few ounces of Pine-Sol in 5 gallons of water, plus a few drops of cheap dishwashing liquid stuff. Pine or hardwoods get the same mix just to keep things simple. A dirty band is a band that 'drags' going through timber, dragging equals wavy.
Scott (diesel gets expensive) B
The drip makes the sawdust stick to things. I suppose I will use it again if the blade is getting stuff sticking to it.
That picture shows the band at perhaps 15 degrees to the bunks. What percentage of band sawmills are other than square and parallel to the bunks and rail or rails the head travels on.
That picture shows the band at perhaps 15 degrees to the bunks. What percentage of band sawmills are other than square and parallel to the bunks and rail or rails the head travels on.
SDB777
I find unique timber and cut it up
What's your estimated band speed? Not sure what 'stick to things' means, but I'm hoping it's not the band that sticking is happening.
Scott (heavy dust is better then floating dust) B
Scott (heavy dust is better then floating dust) B
Cody Colston
ArboristSite Member
The EZ Boardwalk band blade is at an angle to the rails. It is supposed pull itself into the log which reduces the effort needed to push the head rig. On any mill, the band should be parallel to the bunks...if you want flat, square-edged lumber that is a consistent thickness.
Dave Boyt
ArboristSite Guru
The way I see it, green wood is about half water anyway (that would be 100% moisture content). The only time I use a blade lube is when there is a problem with pitch build-up. Not usually an issue with our Ozark hardwoods.
