bandSaw mill trouble shooting!

[FJH]

I,m having a bit of a time with my band mill wandering and diving latly!
Is there an order in which you guys work thru these problems?
The blades are sharpe and and set the alinment of the wheels is correct the guides seem correct! blade tention comes into question for me!What happens if its too tight ,what happens when its too loose?Tim At cookssaw claims the curvature of the blade is a big part of these problems I see no humps top or bottom of any of the blades!Yet every blade does the same dam thing! real frustrated with this!Might get one or 2 good passes in and I start having greif

Any comments on this!
much apresiated
Thanx! Fred

 

[Sawyer Rob]

What brand and model of bandmill??

Rob

 

[redprospector]

Just a shot in the dark, but check your band wheel bearings. Mine went bad, and I almost went nuts before I figured it out. Your problem sounds similar.

Andy

 

[flht01]

Like Rob ask, type of mill would help.

Are the blades new or have they been used/resharpened a few times? All blades from the same mfg? Pitch and band thickness the same?

What method do you use to set band tension?

Are the problems specific to one type of wood or does it do this with several species? Wet (green) logs or dry, hardwood or softwood?

What type of guides does your mill use?

Not trying to get you to write a book but a little info will help troubleshooting.

 

[FJH]

Its my u biult http://photoshare.shaw.ca/messages/viewshow/7685528731-1172719178-38857/preview/page/ Milling fir
7/8 pitch resharpened blades the wheels haven't changed a bunch since i started with the thing!No real wear to speak off there is no crown on the wheels its been working fine until a week back.brand new blades work perfect
first time thru brand of blade makes no diffrence I have wood miser I have lenox and cooks!All are doing the same thing!I tention with a heavy spring!and screw afair.I may be running to tight I have been running a bit tighter than normal! Don't just though you guys may have some thoughts on it!
What went wrong with the wheels you had?

 

[scottr]

FJH , have you checked the bands that dive for the lateral curve with a flat bar and light ?

 

[FJH]

Just a shot in the dark, but check your band wheel bearings. Mine went bad, and I almost went nuts before I figured it out. Your problem sounds similar.

Andy

Thats a possiblity! the wheels seem to spin free with no movment side ways!
They ar tapered roller 3/4 ton truck hubs!

 

[flht01]

...brand new blades work perfect...

Am I understanding this right, new blades cut perfect and the resharps are the problem?

Who's doing your resharpening?

 

[FJH]

YES! correct new blades Have been working fine for the first 2-3 hours!(I have been told that 2-3 hours is All I can expect from these blades in fir!)

My resharpe guy is a real fuss budget!(I BELEIVE) He is a perfection freak!
He sets and sharpens As needed and has done an excellent job for me so far I even took three blades back to him after a pass or 2 and had him redo them to make sure his machine wasn't messing things up! He sets with a tooth by tooth jig not an auto setter 23 to 28 thou offset on 042 blades Ect.Beleive me we have checked the blades!

(I have to beleive its somthing with the mill!)
I will pull thw wheels and check the bearings possibly this weekend and check that out!

Being home made I realize its hard for you guys to give accuate trouble shooting but any info is better than none!

Also I have looked into the curvature thing and (IF) I'm Doing it right They apear flat! No crown top or bottom!

In the meantime
Keep the Ideas ,questions and thoughts coming!

Thanx Guys
Fred

 

[flht01]

I think if it were me, I'd send a few of the problem blades to Cook's saw and have them resharpened. If the new blades are working good for you and the resharps aren't, having another facility resharpen a few to test would help narrow the problem down to either blades or the mill.

Not trying to imply your resharpening service isn't up to par, but having another facility look them over might help.

 

[MJR]

I am by no means an expert, but I can tell you about my experience with a diving blade milling Norway spruce. I took the top cant off and then took the second cant off. I then noticed the prettiest wave pattern in the cut. I could not believe the blade could dive into a log that deep. I changed the blade and made a nice smooth cut. Being a man of science I put the old blade back on. I then made the second prettiest wave pattern I ever seen. I put the new blade back on and made a nice smooth cut.
I was trying to get one more log out of the blade before I changed it. Instead I wasted the log, but learned a lot. I seem to get about 4hrs. on a Lenox Wood Master Blade milling Spruce. Again, I have only milled 38 Norway Spruce logs (yes I am counting) and don’t claim to be an expert.
You may want to look into finding a second source for sharpening your blades. From the looks of your mechanical skills based on your mill, I would bet if there was something wrong with the mill you would have noticed it by now. If it is a mill issue shouldn’t also affect a new blade? Best of luck…

 

[FJH]

I am by no means an expert, but I can tell you about my experience with a diving blade milling Norway spruce. I took the top cant off and then took the second cant off. I then noticed the prettiest wave pattern in the cut. I could not believe the blade could dive into a log that deep. I changed the blade and made a nice smooth cut. Being a man of science I put the old blade back on. I then made the second prettiest wave pattern I ever seen. I put the new blade back on and made a nice smooth cut.
I was trying to get one more log out of the blade before I changed it. Instead I wasted the log, but learned a lot. I seem to get about 4hrs. on a Lenox Wood Master Blade milling Spruce. Again, I have only milled 38 Norway Spruce logs (yes I am counting) and don’t claim to be an expert.
You may want to look into finding a second source for sharpening your blades. From the looks of your mechanical skills based on your mill, I would bet if there was something wrong with the mill you would have noticed it by now. If it is a mill issue shouldn’t also affect a new blade? Best of luck…

thanx for the vote of confidence! BUT!
Maybe I am noticing it but don't see it??
The blades I'm using in question right now are the lenox blades resharpened!
I have new ones on the way but in the meantime I'm 2 cuts into a 24 inch fir and don't want to waste the wood as its prime floor joist material!
Im into it to the 12 inch mark and this has started.
I'm going to lossen the tention first (cheap and easy) then work from there I guess!Normally tention right up and back off 1/4 to 1/2turn lately as these problems developed I have been tightening !Mabe I should be loosening!
If this persists I will send the blades back to the dealer and have them sharpened as suggested and see if that makes the diffrence!

 

[FJH]

OK Guys I tried the tention thing !Two or three diffrent sets looser and another lenox resharp blade no good! still Diving!Wheels will come off this week end for a bearing check and I may surface the wheels maybe there worn more than I can see!
i'll keep ya posted keep the ideas coming

 

[infomet]

If the wheels were the problem, how could the new blades run well?
I can't get the picture(s). How about reloading a bunch.
I have used a hired Woodmizer a lot and never had a diving problem except with a badly damaged blade. We have run resharpened blades for a half day or more in pine. A little less in oak and hickory.

It's hard to believe a tighter blade would dive more.

How about the little idler wheel bearings? If the input side idler were tipped )down), it would get the blade off to a bad start!

 

[FJH]

Ive been thinking ,WHAT A MORON,I messed with the guide bearings a month ago!I may have upset the apple cart .I will start from scratch on the set up and see what washes out!I checked the wheels with a level yesterday the wheels are perfectly level and so is the mill!That dosent mean the guides are right!I'll try heeling them back some see if that does the trick!

http://photoshare.shaw.ca/messages/viewshow/7685528731-1172719178-38857/preview/page/

Make sure you Click on The preveiw portion of the link!

 

[mountainlake]

How much down pressure are you running on the guide wheels. My mill recommends 1/8" but I run around 1'4", it cut a lot straighter. That still wouldn't explain the difference between the new and sharpened ones, are you sure they have enough set, leaving sawdust on the log. Steve

 

[FJH]

Give me a chance to change and to try this i think i may have done this to my self!
i'll let you guys know!

 

[FJH]

Ok I started from scratch It was a way Out of wack OPPOSITE to what I would have thought!The blade rollers were angled Up not down real strange As the blade pulled down not up!I still havent tested it but Everything is now set to 0 , and am hoping things will be back to normal!If this don't work I may pull the wheels and check the bearings!If it does work,I still don't get why the new blades worked and the resharpes didn't!?

By the way 1/4 down on the rollers is where I have them set!
Thanxfor the reminder thou!

Also In regards to the photos I have noticed you have to click on that photo share link twice sum times to make it work ! Go into it then close it ,then go in again and it will work!

http://photoshare.shaw.ca/messages/viewshow/7685528731-1172719178-38857/preview/page/

 

[redprospector]

Sorry I haven't checked this for a few days.
If new blades are giving you 2 to 3 hours the bearings probably aren't the problem. There are a lot of things in the sharpening process that can give you this kind of grief. Check the depth of the gullet on the resharpened blades against a new one, then check the shape of the gullet. Too much hook can give you a problem in Doug Fir, a blade that cuts an old seasoned log fine won't do as well in a green Doug Fir.

The bearings on my mill are pillow block, they seemed to turn smooth but when put under pressure the balls would turn to the bad spots, change everything. I would get from 1 to 5 good cuts, then it would go to crap.

Logic say's that if new blades work fine, the problem has to be in the sharpening process. The best control you can have on blade sharpening is to sharpen them your self. I set mine with the small manual setter from Cook's, and I sharpen them with a (don't laugh) modified bench grinder. This works well for me, and if I have problems with a certain species I can play with the set, hook, and gullet geometry untill I get it right. Take notes so you don't have to invent the wheel again.

Andy

 

[FJH]

Sorry I haven't checked this for a few days.
If new blades are giving you 2 to 3 hours the bearings probably aren't the problem. There are a lot of things in the sharpening process that can give you this kind of grief. Check the depth of the gullet on the resharpened blades against a new one, then check the shape of the gullet. Too much hook can give you a problem in Doug Fir, a blade that cuts an old seasoned log fine won't do as well in a green Doug Fir.

The bearings on my mill are pillow block, they seemed to turn smooth but when put under pressure the balls would turn to the bad spots, change everything. I would get from 1 to 5 good cuts, then it would go to crap.

Logic say's that if new blades work fine, the problem has to be in the sharpening process. The best control you can have on blade sharpening is to sharpen them your self. I set mine with the small manual setter from Cook's, and I sharpen them with a (don't laugh) modified bench grinder. This works well for me, and if I have problems with a certain species I can play with the set, hook, and gullet geometry untill I get it right. Take notes so you don't have to invent the wheel again.

Andy

Andy You may BE THE MAN!
After doing the whole set proesedure a second time with marginal sucsess I found the idler wheel had some movment I have since removed it checked and repacked the bearings which where fine except for being a tad loose! Having said that i am not willing to condem the blades till I have double and triple checked my end first!I will then try sending a blade off for checking by somone else!The new blades being almost perfect may have masked this problem!

Thanx
Fred