Problem with pine and spruce

peterduncan · February 02, 2009, 09:07:29 PM

We are having a serious problem with cutting spruce and pine. After going through a couple of new blades and a Cooke's resharp we are finding that the blade on our Timberking B20 is wandering all over the place. We are not debarking and are using a lot of water. The blade pressure is set at 1000. So...what is going wrong...Frozen logs? Please help.

spencerhenry · February 02, 2009, 10:05:38 PM

what blades, how big of logs, knotty?

my wm lt40 wanders if it is out of adjustment, but spruce especially knotty spruce exagerates all the problems. i use 1.25 x.045 9 degree blades with moderate success

campy · February 02, 2009, 10:06:46 PM

I had a similar problem recently.
The log could have been frozen.

What I did is just went really slow and things worked out well.

peterduncan · February 02, 2009, 10:16:51 PM

We even went at a crawl and it was still wandering. When we shifted to oak and cherry the problem dissapeared. Could it have something to do with the sap being somewhat frozen?

backwoods sawyer · February 03, 2009, 03:24:48 AM

Both pine and spruce will build up sap even with a heavy flow of straight water. If the sap is building up on the saw and wheel, it will not allow the saw to track correctly, causing it to wander. Dribble a little diesel on the saw after each cut, and mix a cup of pine-sol in with the water. If that don't clear the sap scrape it off the saw and wheels.

Meadows Miller · February 03, 2009, 03:35:40 AM

I

mike_van · February 03, 2009, 05:05:43 AM

The plain water you're adding is probably making the problem worse if it's at or below freezing when you're sawing. I've been sawing the last few weeks with no lube, and I've had no problems. Many days, 20F. There is frozen sawdust left on the board & cant, but not the blade. Good flat lumber, sawn as fast as I would in summer.

John Bartley · February 03, 2009, 05:50:09 AM

This appears to be a problem with the "set" of the teeth.

I had exactly the same trouble last winter sawing frozen white pine and solved it by pushing the set out to approximately 0.028". Lots of lube to keep the pitch off the band also helped, but the solution was increasing the set.

cheers

John

Meadows Miller · February 03, 2009, 07:04:30 AM

Gday

What hell happend there

:

Ill finnish what i started ;) :D :D ;D

I also think it would have somthing to do with either sap buildup on the band wheels and blade or probley the main one is Improper sett I use to go pretty heavy on the sett on my bands when i was sawing pine to avoid the packing you can sometimes gett My lill band mill had solid cast alloy bandwheels that had scrapers on both the wheel and and on the back of the body of the saw which keept things running pretty dang smooth i never had any real problems on my mill with bands wanting to wander in the 5 years i had it ;) ;D ;D 8)
Good luck Mate

Reguards Chris

MartyParsons · February 03, 2009, 07:12:27 PM

Spruce and hard knots like in pine, and Frozen logs will make a mill work. If there is an alignment issue, drive system slipping, blade tension issue it will show up during the winter, or on a knot. Blade set, hook angle, and tension all will have an effect on sawing. Wider tooth spacing will also help with the spruce to help carry away the chips. Pine and Spruce also have a cabinum layer under the bark which is hard to cut it wraps around the tooth making the blade dive. As talked about above the blade needs to be kept clean, the set on blades is around .020 so if the sap builds up beyond this or even takes the set away by build up the blade starts to dive. 1 pint of pine sole to 5 gal of water or windshield washer fluid works well.
From my experience pine saws easier if frozen because it is all the same denisity, you dont have a hard knot then soft wood. Hope this helps.
If everything on the alignment seems good track the band back further on the wheels so the tension is pulling across the teeth instead of the body of the blade.
Marty

redprospector · February 04, 2009, 12:25:39 AM

I had a similar problem on some Sugar Pine logs a couple of weeks ago.
I had tried everything I could think of, then jumped up and down calling my mill ugly names, and when I took the blade off I slapped the idler wheel just for good measure.
When I slapped the idler wheel it moved, not turned, moved. so I looked closer. The set screw's had backed off on one of the pillar blocks on the idler shaft, wearing a pretty bad spot on the shaft. Had the machine shop build me a new shaft (the bearing was ok somehow). Problem solved.
It's pretty unlikely that would be your problem too, but if all else fails look for the unexpected.

Andy

peterduncan · February 04, 2009, 07:22:43 AM

Thanks for all the great advice and we are checking each one. In some places on the boards we are finding pockets of thick oozing sap, almost as thick as chewing gum. I am sure that the sap throughout the log is making things worse. The blade movement has been so bad in some cases we are getting a roller-coaster effect.

Tom Sawyer · February 04, 2009, 09:01:37 AM

It could also be half frozen logs causing the problem. If they are frozen all the way through it is much easier to saw than if they are only half frozen. Sawing spruce has caused me to tear my hear out more than any other species.

Tom

petefrom bearswamp · February 04, 2009, 03:17:50 PM

Tom,
I have sawed both Red and Norway spruce without undue problems. some wandering over knots tho. What sort of problems do you encounter?
Pete

Tom Sawyer · February 04, 2009, 04:48:19 PM

If the blades are not very sharp and set exactly the knots will cause wandering. There are times that I can cut spruce without problems and then the next time I can't seem to make it cut straight. I would consider wandering over the knots to be a sign that the blade needs to be changed. I know that spruce can be cut without that wandering and I hate to settle for anything less!

Tom

bull · February 04, 2009, 05:22:30 PM

1000lb blade tension is not enough !! that will have spuce looking like the tide is coming in!!
I run 2800-3000 lb blade tension for spruce and you have to slow your feed rate... Dawn dishwashing liquid and straight winshield washer fluid for the cold weather/frozen logs !!!

redprospector · February 04, 2009, 08:47:56 PM

I agree, it sounds like the set isn't enough. But since new blades were used I assumed the set would be pretty close, that's not always the case though.
In "pitchy" wood like Pine, and Spruce I use diesel mixed with bar oil for a blade lube. It keeps the blades really clean. I can't remember the last time I had to clean a blade after taking it off the mill, and most of what I cut is Pine, and Fir.

Andy