I have 3 sections of a very large post oak that were cut almost 2 years ago and have been drying in my garage since. They are "horizontal" sections cut at the main split of the trunk and are each roughly 2' x3.5' around and from 6" to 12" thick. Because they were cut from the main split in the tree they each have 2 sets of rings kind of mashed together. I wanted to slab them out into 2" thick pieces for coffee tables and other furniture. I've had problems finding a sawmill willing to cut them which is why they've been drying so long, and I finally found a willing coworker with a sliding band saw mill large enough to cut them.
We spent 2 solid hours and 2 different blades (one was brand new and oiled because we bent the first one), with different water pressures and were only able to get about 5" into one cut on the first one. Each time we would start cutting the blade would get about 1/2" in then the wood would jump, the blade would bind, and it would ram the logs into the side of the mill. Then we would have to take the blade off the mill and spend 10 minutes with hammers, pry bars, and chisels to free the blade so we could try again. Even with the metal braces on the mill, we couldn't find a good way to secure them to the frame so they wouldn't jump. Eventually we cried uncle because we weren't making any head way and didn't want to damage his mill.
The wood is so hard it's basically concrete and we are out of ideas. I am avoiding having to use a chainsaw because it would cause me to lose so much of the wood to each cut. Is it because we are cutting across the grain, or are there any ideas on how to cut such hard dry wood on a band saw mill or other method?
I'm a little confused here. You basically have a couple crotches that you already had sawed two flats on correct? You've got to find a way to stabilize it on the mill bed. I've never had to, but even if you had to put some pieces under the crossbars that screw into the crotch piece....Just don't then saw down into the screws.
I cut Osage sometimes. I've cut dry osage and it's so hard the blade will want to follow the grain to some extent and I may get some waves, but it never "won't cut" it if you have a sharp band. I then go back over the wavy piece with a beam planer. Sometimes I'll get some tearout with that, so after that I'll switch to the belt sander and 50 grit.
Are you saying when you're cutting with the band saw, that it just stops the blade? Or is it cutting wavy? What degree band are you using? Woodmizer(my brand) has 4, 7, 9, 10 etc. I would use the lowest, the 4 degree on it. It takes less of a bite so it won't bog down an under powered band mill. It's like putting it in first gear when climbing a hill.
The wood has to be positioned against stops on the mill so that movement isn't possible. If there have to be gaps between the wood and the mill stops-so that the wood can be positioned in the bandsaw throat- then position a wood block in there so it cant move when the blade tries to push it sideways. Otherwise position the piece up against the metal stops of the mill so it cant be forced sideways when being sawn.
You're saying the cut width is from 2' to 3.5' wide? What kind of saw is it and what HP does it have?
Where are you located?
Its a 24" band saw mill so we are running it lengthwise through the "short" side of the sections so the cut length is 2" wide. The pieces themselves were cut from the tree with a chainsaw and are not level, so they can tend to wobble.
When they're not secured with metal stops, the blade hits them and catches the wood and sort of jerks it into the side of the mill. If we use the metal stops attached to the mill bed, it tends to almost pick up the wood which binds the blade and then sort of tips them up against the stops, pinches the blade and bends it.
We were able to somewhat stabilize the logs a couple of times for the first half inch or so but if the log doesn't jump when the blade hits it then it just stops the blade in the wood. We considered screwing them to the mill bed but since I am using them for furniture pieces that would leave holes in at least 1 slab out of each section and I wouldn't be able to use it with any sort of clear finish. I may get to that point if I can't stabilize them some other way and it may seem a little petty to avoid cutting any slabs by risking a few but I just want to exhaust all my other options.
Because we are cutting them into 2" thick sections and have only been able to get a few inches in, It is hard to tell what the cut looks like (wavy or otherwise). The mill isn't mine and I am still fairly new to the milling process, so I've reached out to the owner to see what degree blades we were running and what the HP was.
I cant see how the blade will stay out of trouble if the wood can move under the force of sawing. It should be "against the stops" so it can't slide in the direction the blade is forcing it. On the other side it should be clamped so it cant lift off of the bed.
A photo or two may help others spot something helpful.
Kbush, I can't understand at all what you're trying to describe. Pictures are worth 1000 words they say....
I think he's trying to mill thick cookies (6-12") that were cut from a crotch, which resulted in a oval shaped cookie (24x36"), and now they're placing those cookies on the mill trying to get multiple 2" thick cookies.
Alan
Kbush it sounds like you want to cut 2" thick cookies. Post Oak is extremely hard to cut....even more so when it's been drying for 2 years, and it will stop a saw blade (it feels like you've run into metal that refuses to be cut). Trees from Ft. Worth and west are going to have really tight growth rings due to the frequent droughts that we have which makes them harder than a woodpecker's lips. Your wood can be cut but it will take a lot of tricks to make it happen.
I'm just north of Decatur, Texas and if you can bring them here, we can cut them on my mill. It would also be nice to meet another forum member. I'm retired so my schedule is wide open and SAT/SUN is fine. PM me if you're interested.
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Sorry, had some trouble uploading the photos. The picture in the bed of my truck is from the day they were cut, the other one is a more recent picture. Yes, they are currently cookies and I'm just trying to cut them down to smaller 2" cookies so I can get more slabs from each piece
If you can see, the cedar planks sitting on top of the stack are more of what I am hoping to get out of the oak sections: 2" thick slabs that can be made into coffee tables and other furniture items.
A chainsaw mill would probably do a good job cutting that wood, how big of a bar will your saw run ? If you have a bar large enough you could maybe do it with one of those clamp on beam cutters. Just screw a trimmed straight 2x6 to the side of the round and guide the saw down the board to square up the top, move the board and cut off what you want.
Use a 4 degree blade and make sure the wood can't move. Have some water or water/soap running on the blade, it is most helpful if the mill has a tension gauge, which will show a drop in tension if blade temperature rises.
You will need to have the blade buried in the wood for best results, in other words don't expect the blade to "skim cut" the wood to get it even.
To hold such thin slabs I would screw the piece to another board that can be clamped securely. Several carefully placed drywall screws about 3/4" into the work piece going first through the clamping board. You might be surprised how little a screw hole would show esp. in green wood.
Quote from: Kbush on October 25, 2018, 01:27:49 PM
If you can see, the cedar planks sitting on top of the stack are more of what I am hoping to get out of the oak sections: 2" thick slabs that can be made into coffee tables and other furniture items.
Note those cracks in the Oak cookies. Oak won't behave as well as the Cedar. Thin Oak cookies, especially large ones, can become heavy potato chips, with splits and cracks.
The pieces MUST be held firmly while sawing. I have cut bone dry Cypress knee cookies, sometimes even having to rotate and re-clamp wide sections in order to make a pass. Slightest bit of wiggle and the piece will break off. That Oak can be clamped or screwed, and rotated if necessary to get the wide sections cut.
How about sawing each side of the cookies to flatten and bring them parallel. One 3 or 4 inch sound cookie is preferable to three two inch cracked potato chips.
I see firewood. Better off getting a new crotch log several feet long so it can be clamped and starting fresh.