I did a search on this forum about sawing frozen wood.
Some of the suggestions were to saw from the top of the tree. ( Didn't help)
And to use Woodmizer's 4 degree hook blades.
I've ordered some of the blades but I got to wondering if anyone had good success using thier usual blades ???
Hard to believe the logs are frozen already but the owner had one of those 'laser' thermometers and they were all about 30 degrees !!! The ones we tried to saw were thawed on the outer inch or so.
Thanks for any input.
Well a few days of 20° will certainly do it. But, wait a day or two and they will be thawed again. ;D
Sorry, wish I could help with advise on the sawing. Not many opportunities up here to saw oak.
The worst sawing is when there half froze...I try to wait until there froze solid. I sharpen my own blades and use a 6 to 8 degree hook angle.
I agree with Larry, they are most likely partially frozen which is the worst in my opinion. I had some walnut that I could not cut right and asked on here what the problem was. Electric Al who is down the road pointed out that they thaw some in sunlight.
I actually like to cut walnut or cherry when it's totally frozen. No blade lube and the blades cut it like butter.
SB, I normally use 9° bands on frozen oak but have also sawn a lot with the standard 10° band. Both will do a good job but you do have to go with a much slower feed rate. I have not tried the 4° bands yet but have 2 of them to try out as soon as we have cold enough weather to freeze a log. I certainly agree on the problem of sawing partially frozen logs, try to avoid if possible. White pine seems to saw as well if not better when frozen as the contrast in hardness between knots and regular wood is not as great.
Bill
I don't have a lot of frozen hardwood experience, but we did get a box of the WM 4° bands last winter, and they really helped, especially in knotty frozen pine. Most of the problems I have had sawing have been due to an out of alignment mill. I sawed out 1mbf of cherry, and I had a lot of trouble with the cut moving up and down at the begining of the cut, and also a slight crown on top of the cant. The 4° helped reduce this, and I am sure with the alignment, I would have no problem sawing frozen cherry now.
Dave
We sawed alot of frozen wood last winter and just used a regular grind and set with no problems...except that the dang sawdust would just freeze to the boards and the only way to get it off was to scrape it off. I found that the side of a framing square worked just fine for that.
Quinton
Were you using a lube for it to freeze? Maybe needs some antifreeze in it.
I don't run a band mill, but, even on a circle mill, partially frozen logs are tough. You're sawing through 2 types of wood - frozen and unfrozen. And, you're doing it in the same cut.
The only time I've had much problem with sawdust freezing to the lumber is in partially frozen wood. Feed rates come into play. You tend to slow down, which gives finer sawdust, which spills out of the gullets quicker, which freezes to the lumber, which pushes the blade.
Is that the same problem with the bandmills?
I think it's a similar problem, Ron.
I slowed down to a crawl...literally: I crawled next to the head so I could see the space between the blade and the blade guide and see when it was starting to dive. The dust was slightly frozen to the log but brushed off.
I tried it with water and without. Not much difference.
Nice straight cuts getting the bark off and then WHAMMO :D
This happened to me a couple of weeks ago with oak of my own and I just cut hemlock instead and when I tried the oak later it was fine.
I'm wondering if the log was completely frozen if the normal blades will work on hardwood? Why is the smaller hook angle effective ?
Norm, do you use your usual blade to cut frozen wood ?
I use 10 degree blades year round on all species (hardwoods mostly). Same as everybody else, froze sawem thawed sawem, partially go do something else. Partially froze is a pain any way you look at it.
We sharpen our own blades, and have to back off to 8 degrees or less to cut frozen wood. The reason for less hook angle is it makes the blade want to penetrate more-the harder the wood, the less hook angle you want. Hook angle is kind of confusing-what we call 10 degrees is actually 10 degrees from perpendicular.... or in reality... an 80 degree hook angle. when you "reduce" the hook angle to 4-8 degrees, you are actually increasing the hook angle to 82-86 degrees. The closer you get to straight up perpendicular, the more the blade wants to penetrate the wood.
I do Joan. We have no softwoods around here and I cut a lot of white oak so I just use the same blade for everything which is 9 degree.
I have a bunch of white oak coming in to cut and have been thinking of trying out the 4 degree blades, be interested in how they work out for you.
Any of you that haven't tried the 4 degree blade will not be disappointed. I keep them on hand for sawing very dense woods like sinker heart pine - which can be like glass and aged sycamore which is also very hard. They'll cut nice and flat every time.
Try 'em out. :)
LOGDOG
Also ... widen your set out to eliminate the sawdust freezing on the face or the boards.
LOGDOG
Hook angle is a relative measurement based on 0° being vertical. The more the tooth leans into the direction of travel, the higher the hook angle and the more aggressive the blade. If the face is leaned to the rear, away from the direction of travel, you get a negative hook but the angle is still measured from vertical.
To change the meanings of hook and to change the relativity of the point of the tooth to the direction of travel is to redesign the science. What you are doing is calling left, right; up, down; backwards, forwards and relying on head pressure to define feed speed when it's actually the tooth's configuration that defines it.
The more positive hook a tooth has, the more material it tries to take. until it begins to chatter. It will either stop the blade or jump out of the wood. The less angle, the more the point scrapes rather than digs and the less wood is removed per inch of travel.
If someone cares to redefine the relativity, fine, but, you have to re-educate the whole rest of the world.
If you think that less hook drives the blade into the wood deeper, turn the blade around and you should cut faster than any man has ever cut before.
I tried that once Tom. Shore was a lot of smoke for a minute :D :D :D.
I didn't dare laugh at Tom. :-X
I remember trying to install a blade on a brush saw backwards. I tried like the dickens, but all I seemed to do was scrape and girdle the bark off the trees. That never topped the time 20 + years ago I got a brush saw in my hands with a new blade, that unknown to me being a self taught kid around a saw, it was never sharpened or set. ::) Took me several evenings after school and I never even got an acre of brush cut. :D :D :D
I may be wrong..... I certainly have been before. But let me explain a little further.
Hook angle is indeed measured in degrees from vertical, or perpendicular. My point was that as you decrease degrees from vertical, you are opening the face of the tooth. As you increase degrees from vertical, you are closing that down.
The softer the wood, the easier it is for a tooth to penetrate. And you are correct when you say the tooth configuration, or hook angle, determines feed speed. When the correct hook angle is used for the proper density of the wood, maximum speed is achieved. Either more or less hook angle than optimum results in a blade that wanders, that doesnt want to penetrate, and results in poor lumber and short blade life. A blade wanting to overfeed itself causes as much problem as a blade that cannot penetrate fast enough to feed itself.
A lot of what I believe concerning band saw blade behavior and hook angle comes from the early days of having bandmills. Back then, there was no internet chat forums, woodmizer still hadnt come out with the doublehard blade, and I spent a lot of time on the phone with the owner of suffolk machinery diagnosing and learning why we had various cutting problems. Also, there were no other bandmill owners in this area to talk with. His troubleshooting guide on hook angle and set got us through those years. I dont completely agree with everything they say now, but most of it still holds true, at least for us. They are the ones that talk about reducing hook angle to increase penetration in harder woods. You can read a far better explanation on their website under the troubleshooting guide. Is he right? I dont know, but it makes sense to me.
As far as putting a blade on backwards......been there, done that, on the bandsaw, on the edger, and on the chainsaw. Oh yeah, the table saw too.
The 4degree blades came. They worked fine yesterday. Sawdust was still pretty frozen to the wood. Saw and logs both always in shade. High temp yesterday 24F.
The blade was getting dull yesterday after 4 logs that made 150 bf of 1x6.
Put another blade on this morning and it kept diving ::) Tried turning the log around, changing feed speed, different blade tension, scraping the bandwheels and nothing helped.
I quit.
The only thing I can think would do it is the dust freezing to the wood behind the cutting edge of the blade and because of a change in grain ( or something), more dust builds up under the blade and it dives. It can't go up, anyway.....
I am now very good at backing the blade up :D
Maybe I'll give it another try in the spring and maybe I will just never agree to saw anyone else's hardwood ever again. This was my second job.
Don't give up on it. You just might have to back off and wait till the log is completly frozen. I know that I run in to simalar trouble in hardwood when it is very dry on the outside edge of the log but the inside of the log has more moisture in it. It is like Ron said you are cutting two different types of wood and when you get things adjusted to cut the one type then the other type in the same cut will make the blade do strange things. I know that some times in the dry logs one blade will cut it not to bad then the very next blade doesn't want to cut it at all but it will cut other types of wood just fine. Try a few more blades as your second blade might be one of those that only likes certain types of wood.
Sprucebunny,
Couple of questions for you:
1) How many horsepower do you have?
2) Do you have your own setter and sharpener by chance?
3) What is the average diameter of the logs you're sawing?
I used to saw red oak with my WM commercially in WI all year long -including winter. We even sawed when it was -35 degrees. So I know we can get your blades to cut. Just need a little more info. Don't get down just yet. ;)
LOGDOG
Thanks for the encouragement, guys :)
If the logs aren't solidly frozen Then oak logs must freeze at a lower temperature than water. I guess that's a possibility.
The logs are 10-14" and far from straight grained. The temperature when I brought my saw home today was about 32F. It has been around 15 degrees F overnight, lately and 30-35 during the day.
It seems that maybe the blade is causing enough friction to slightly melt the area of the cut. Why else would the sawdust be so hard to scrape off ??? If I had my own setter , I would try slightly more tooth offset, maybe, but I don't.
I have 20 HP and it hasn't bogged down a bit. I have been feeding 1/3 ? slower than normal.
I needed to move my mill out of there before it snowed. I don't have any oak of my own to screw up so these experiments will have to wait ;D
Being from central Texas I may be easily confused but whats a frozen log? My freezer is not large enough to hold a log and it sure does not get cold enough here to freeze without some help to often! Of course we are now in a cold spell. its only 46 out. But next week we will be back to the 60's!
Just grind your blades at 8 degrees and set .019-.021 you won't have much problem untill you get to -10 degrees below 0 then wait for warmer weather.
I`ve been useing .055 9 degree blades with my 20 hp B&S,
with 19" wheels. Have aliminated almost all wavey cuts. No
noticeable change in feed speed. Blades are lasting as long as
the .045s I had been useing.
arj
Joan, have you milled unfrozen oak without a problem?? Some light mills have problems with some blades in oak.Call Timberwolf on long Island ask for Art,tell him your problems,I bet he will send you some blades that work fine.
Bandmiller2, yes. I recently cut about 400 BF of 1/2 thick and 4/4. Had some problems with the first log but a couple days later every thing went fine. Never did try cutting the difficult one again. I suspected it was partly frozen. It looks like a featherboard after what I did to it :D
Maybe I'll try a couple of the 9 degree. I find it hard to believe that one degree difference in hook could make a big difference ???
Sprucebunny,
Have you checked the alignment on your blade guide rollers recently with the alignment tool? I've got a feeling somethings not quite right. Might not be the blade.
LOGDOG
Quote from: Tom on November 14, 2007, 09:39:28 AM
Hook angle is a relative measurement based on 0° being vertical. The more the tooth leans into the direction of travel, the higher the hook angle and the more aggressive the blade. If the face is leaned to the rear, away from the direction of travel, you get a negative hook but the angle is still measured from vertical.
To change the meanings of hook and to change the relativity of the point of the tooth to the direction of travel is to redesign the science. What you are doing is calling left, right; up, down; backwards, forwards and relying on head pressure to define feed speed when it's actually the tooth's configuration that defines it.
If someone cares to redefine the relativity, fine, but, you have to re-educate the whole rest of the world.
The more positive hook a tooth has, the more material it tries to take. until it begins to chatter. It will either stop the blade or jump out of the wood. The less angle, the more the point scrapes rather than digs and the less wood is removed per inch of travel.
If you think that less hook drives the blade into the wood deeper, turn the blade around and you should cut faster than any man has ever cut before.
Tom I'm with you on this one, sure is confusing when people say less hook makes it bite more in hard wood or any wood. Common sense says more hook, more bite, more self feed. Seems like if you ran 0 hook the machine would have to push the blade in the wood. A good example would be a radial arm saw with a 15* hook verses a 0* hook. Why does less hook work better in frozen or hard wood? Still confused Steve
Quote from: ladylake on November 26, 2007, 03:54:08 PM
Quote from: Tom on November 14, 2007, 09:39:28 AM
Hook angle is a relative measurement based on 0° being vertical. The more the tooth leans into the direction of travel, the higher the hook angle and the more aggressive the blade. If the face is leaned to the rear, away from the direction of travel, you get a negative hook but the angle is still measured from vertical.
To change the meanings of hook and to change the relativity of the point of the tooth to the direction of travel is to redesign the science. What you are doing is calling left, right; up, down; backwards, forwards and relying on head pressure to define feed speed when it's actually the tooth's configuration that defines it.
If someone cares to redefine the relativity, fine, but, you have to re-educate the whole rest of the world.
The more positive hook a tooth has, the more material it tries to take. until it begins to chatter. It will either stop the blade or jump out of the wood. The less angle, the more the point scrapes rather than digs and the less wood is removed per inch of travel.
If you think that less hook drives the blade into the wood deeper, turn the blade around and you should cut faster than any man has ever cut before.
Tom I'm with you on this one, sure is confusing when people say less hook makes it bite more in hard wood or any wood. Common sense says more hook, more bite, more self feed. Seems like if you ran 0 hook the machine would have to push the blade in the wood. A good example would be a radial arm saw with a 15* hook verses a 0* hook. Why does less hook work better in frozen or hard wood? Still confused Steve
I could be wrong, but I thought it has to do with the higher hook angle would dull faster in harder wood, kind of like a square chissel chain will dull faster in some wood than the rounded corner ones.
Because the more you lean the tooth into the cut (direction of travel), the more wood it tries to remove and the more horses you need to do it. If the wood is hard enough, the tooth will not penatrate deep enough, will quit cutting and will jump out of the wood. It's what is called "chatter". Either the tooth will jump out of the wood, or it will inbed itself so deeply that it brakes the engine and the engine stalls.
When the tooth is allowed to stand up straight, it is just scraping the surface of the wood and not digging in. The curls are smaller, the blade is under less stress and there is no chattering. A negative hook would allow the tooth to "skate" over the surface and, for the love of mike, I don't know how it would cut, but it does. I think you see negative hook in things like steel cutting but I'm really not familiar with it.
It's kinda the same thing as digging your heels in to keep a roped horse from towing you off. If you lay your feet flat on the ground, you will just skate along.
Quote from: Tom on November 26, 2007, 09:04:12 PM
Because the more you lean the tooth into the cut (direction of travel), the more wood it tries to remove and the more horses you need to do it. If the wood is hard enough, the tooth will not penatrate deep enough, will quit cutting and will jump out of the wood. It's what is called "chatter". Either the tooth will jump out of the wood, or it will inbed itself so deeply that it brakes the engine and the engine stalls.
When the tooth is allowed to stand up straight, it is just scraping the surface of the wood and not digging in. The curls are smaller, the blade is under less stress and there is no chattering. A negative hook would allow the tooth to "skate" over the surface and, for the love of mike, I don't know how it would cut, but it does. I think you see negative hook in things like steel cutting but I'm really not familiar with it.
It's kinda the same thing as digging your heels in to keep a roped horse from towing you off. If you lay your feet flat on the ground, you will just skate along.
You also see negative hook in melamine table saw blades and sliding compound miter saw and radial arm saw blades. You would think that they wouldn't cut at all, but they do.
Hello, Very new to your forum but been cutting wood for over 30 years. As far as frozen goes, ya freezin in and freezin out is something we all deal with in fall and spring in British Columbia but there is some things you can do to make it work. #1 fill your blade lube with windsheild washer anti-freeze and use lots of it to make your blade stay soaked. You want to try to aviod the spill from freezing back on to the cant or board before your blade passed through the cut. Go to as narrow a band as you can try to reduce the time that the blade is travelling over the freshly sawn spill. Adjust your feed speed accordingly, understand and know that there will be some logs that just cannot be cut while they are half frozen, at times we just set them aside when we run into them and let them freeze up good and saw them then. Anyhow wish you luck and keep on sawing!!!
I don't know this to be fact or any such thing as that but the blades with negative hook angle tendes to remind me of first watching my grandfather and then later doing it myself but have you ever used a piece of broken glass to shape a ax handle it will shave it off a bit at a time.
In the studies I have done with the blade angles and stuff there are some that teach that the more hook angle the faster the sawdust will go to the bottom of your gullet and in the harder woods the sawdust will start to spill over the gullet and past the blade which will affect your cutting as well.
My theory is that more hook is causing it to self more in harder wood, more to hook onto causing the blade to take off to which ever side has a little more set. Just a theory. Steve
Ok, here is a brush saw tooth
(https://forestryforum.com/gallery/albums/userpics/11009/SD_sawtooth1.jpg)
The top tooth is fresh out of the packaging sleeve and has a pre-sharpened and set tooth. The angle we use to sharpen the tooth is 20 °. The direction of the blade motion is to the right. Notice the negative (to the left of 90°) set of the tooth. The very tip of that blade it where the cutting takes place.
Now notice the bottom tooth. It has hit a field stone or iron and that hatched area has been taken off. The cutting edge is rounded over. It will take about twice the effort and gas to cover the same area of thinning that the well sharpened blade above does. Follow that damaged sliver down to the left and learn why. You now have a blade that is hitting the high spot which isn't sharp, so you might as well have a hub cap attacked to the saw. You do get some cutting, but you have to force the saw into the wood, which causes more friction and your saw looses power to spin the blade. ;D
I don't think we're talking about dull blades as you can put on a fresh one with to much hook and it wont saw straight. Steve
ladylake, you are probably right. I was just looking for something to say. ;)
Try throwing the gage on the blade and check that the guides are absolutely level. If it still wants to dive increase the tension and adjust the guides to a slightly upward angle. I have often wished I could just turn a dial on the guides to get thru problem logs. Anyone ever see that on a bandsaw? Joe
'Bout this time last year I got to try sawing some very green, very frozen white oak with my 10 degree "softwood" blades. The blade was all over the place.
We rolled the logs into the shop (they weren't very big -- came all the way from Ontario in the back of a van) and let them thaw out for a couple of days. Sawed like a dream after that.
I have problems with my blade diving when I cut Douglas-Fir with frozen sapwood. Not a problem when the blade is fully in the sapwood, not a problem when it's entirely in the heart wood. Guaranteed to dive if it hits both in the same cut.
Hey, kootenay sawyer, watcha doin' stealing my business name ;D ;D?
Hey Brucer, family members bringing you logs from the east now? ;D
Since the mill sawed fine one day and not the next, I'm guessing the problem was a combination of things that you all mentioned, but not the blade guides.
The logs have been on the ground since last spring and some of the bark is coming off so I think the outsides may be dryer. The problems always occur on the second cut- the one after the bark is off- so there could be dryer and wetter wood.
Also I think wild grain and wood tension is a factor.
If it had been my log, I would have cut it through the middle to see if it cut funny there but the customer doesn't want his oak in funny shapes ;)
If I get caught up cutting firewood, I'll try an oak log I found in my yard.
Quote from: SwampDonkey on November 30, 2007, 07:30:10 AM
Hey Brucer, family members bringing you logs from the east now? ;D
Naw,
family knows they're supposed to bring maple syrup ;D.
Got a lot of transplanted Ontarians and Quebecois in these parts. Something to do with the skiing.
Rossland = Red Moutain = Nance Greene & Karen Lee Gartner.
Another thing I re-learned yesterday about sawing half frozen oak. When you can not get a good cut, try changing bands. Some bands which will cut un-frozen wood just fine will not cut half frozen wood at all without waves. I believe the problem is inconsistent set in the teeth either because it was not set properly or the band hit a stone or something in the bark that affected only a few teeth. As soon as I changed bands the problem went away and I was able to saw until that band was extremely dull. I do not believe sharpness is as much of an issue as set,imho.
Bill
Brucer, seems to me job would be first priority wouldn't it? I've skied before and it didn't pay too good. ::) :D
I'm not educated enough in the sports arena so them names don't mean a thing to this country boy. ;D
talking about negative aqngle blades and how they cut, next time you need to cut some sheet metal (barn roofing or siding), try putting a plywood blade in your skillsaw backwards
you will be amazed at how good it cuts through the tin. It makes no sense that it will cut at all, but somehow it does.
Just be careful doing that as carbides can come off and go flying.
DON'T USE CARBIDE.
Don't ask me how I know this.
I was the one that always got to cut the metal, maybe because I was deaf, deef, whatever, nobody likes the scream, use hearing protection.
plywood blades dont have carbides...
Some do, do a google. :)
When I put the replacement steal on the shed roof this summer/fall we used a skill saw to trim some pieces. We did the whole stack at one time. I think 10 or 11 sheets at once. Eye protection was used and I was told to stand back during the cutting. ;)