too much lube!

[Okrafarmer]

So today I put on a brand new Munkfors blade and started trimming up a magnolia log. It was first time for that species to me, and I was enjoying the awesome growth rings in the tree, and how they ripple around the knots just so. But my blade lube was clogged up and not coming out, so I took the nozzle off the sprayer and cleaned it out and put it back on. I then engaged the blade and experimented with spraying the lube on (diesel fuel). When it was coming out pretty good, I was about to go into the log with the blade, but hadn't made it there yet, when
Schproing!!!!! 
The blade came off the drive wheels, ricocheted around a bit on the mill bed, and came to a stop. Still in one piece, not broken, but I guess 5-10% of the teeth are broken off from hitting the mill. Ah snap. :-\  Brand new blade.
Well, it was about time to go home anyway, so I didn't reblade at that time. Now I am wondering what to do. Part of me says, put the same blade back on and see if it will cut. After all, it's probably just going to be thrown away anyhow.  :-[  :'(  The sharpener guy will probably refuse to sharpen it if I send it to him, but if I tell him it was still cutting fine after I broke it, then maybe he will still sharpen if for me. But then again, it may not cut.

And man, what about that thing just popping off like that? I don't think it was an alignment issue, that I know of, but probably just too much lube. I guess. . . .   ???

[Migal]

Im still learning but do turn the lube on and tension blade with lube and spin to check alinement on band wheel then one more time with engine for a few seconds then recheck alinement on all new blades sounds to me some build up then when turned lube on blade got slack when clean from lube Just a thought!

[Okrafarmer]

The blade was already tensioned (very hard to tension and detension it on this sawmill compared to some brands) and I had already cut several passes with it.

[Migal]

was there any build up prior to lubing?

[Okrafarmer]

There was no buildup on the blade.

[Migal]

well my experience is what has changed since all was well then go from there GL

[hackberry jake]

I would guess too much lube as well. Diesel is pretty slick. My manufacturer told me 2-3 drips a minute of diesel/bar oil mix is a good starting point. He said if too much gets on the band, it slips off the wheels. The only times I have had one come off is with either too much lube or I got the band hot and lost tension.

[ladylake]

I've had that happen, as mentioned 3 drips a minute or so.   Also when the v belts get a little rounded the blade will come off easy with diesel.  Putting the clutch in slow and easy will help.      Steve

[Brad_S.]

I agree with the above... you have lost the crown on your bandwheel.
New v belts should help mitigate that.
When mine slip off, they usually slip off to the rear and jam between the bandwheel and guard housing, destroying both the band and often the staying forward enough to have the teeth destroy the v-belt as well, thus requiring that I change them out anyhow.

[bandmiller2]

I would say a slight alignment/crown issue,too much slippy just put it over the edge.Always use minimum lube to get the job done.My homebuilt bandmill has plywood covers over the bandwheels if a band comes off it digs into the ply and stops quick,no dulling no damage.If you have steel and theirs room you can install plywood,best glued on,no fasteners to hit. Frank C.

[JFarmer]

 My mill has done that before back when I was running belted wheels. Once the belt got wore down, I couldnt keep blades on. I put new belts on and it solved my problems. Hope this helps.

[barbender]

I used to have a mill that had trailer tires for the band wheels, if you got too much diesel on there it would jump right off, it has nothing to do with crown. Diesel is just roo slippery to get too much on there.

[ladylake]

I used to have a mill that had trailer tires for the band wheels, if you got too much diesel on there it would jump right off, it has nothing to do with crown. Diesel is just roo slippery to get too much on there.

  Have to disagree, using diesel bands come off old worn belts easy. Put new belts on and blades stay on a lot better.  Steve

[barbender]

I won't argue with your experience, Steve ;) The thing with pnuematic tires is that they deflect under tension, I don't know what Okra is running for wheels. But on mine if you got to much diesel on there the blade would invariably jump off  :(

[Brad_S.]

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[Brad_S.]

I used to have a mill that had trailer tires for the band wheels, if you got too much diesel on there it would jump right off, it has nothing to do with crown. Diesel is just roo slippery to get too much on there.

It has everything to do with crown and your problem with the tires proves it.
There is no crown on a trailer tire and it was easy to throw a blade with too much diesel. The tire acts the same way a worn belt would.
I agree, use diesel sparingly but a good crown will allow for much more forgiveness.

[Okrafarmer]

Hey, guys, pneumatic trailer tires it is. They do have a crown when properly inflated. Getting the band to stay on the crown, now that's the hard part. I've done a bit of milling since I last posted about this, and I have found that with reduced lube, the problem is pretty well under control. I always run the risk of getting out of control though.

As far as the blade contacting the drive v-belt, I don't have to worry, since there is a lot of solid metal between the blade and the drive belt, it couldn't possibly get to it.

[tyb525]

I don't think it has much to do with crown, too much lube will cause a blade to slip off, crown or not. Yes there are bandmills out there that run steel wheels with no crown- they are very finicky but they can work.

Too much slipperyness, and a shock to the blade (engaging too fast, starting into the log too fast) can cause the bandwheel to spin under the blade. When that happens, all bets are off as far as blade tracking. The easiest way for the blade to go is off.