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(11-07-2018, 10:11 PM)EdL Wrote: No idea what a nail sounds like with a chainsaw mill....my bandmill makes a distinct "zing" sound.
Game over.
Ed
As Ian said, you usually don't actually hear the chain when it hits a nail but you will usually feel it, though not always. With soft nails like many of those used in framing the chain will usually cut right through though you feel it has hit something and it cuts more slowly afterwards. But if you hit a hardened nail, a screw, or a dreaded insulator lag bolt, the chain stops cutting dead in it's tracks. When that happens it's pretty common to break one or several teeth clean off the chain, and dull every tooth. I lost one tooth when I hit one of those nails in the first log in this batch, but the chain continues to cut just fine after I ground the teeth back enough to remove the damage. Fortunately, I've never had a chain break, and hope I don't.
Which brings up an interesting subject, chains. The chain you use for milling lumber is different from what you use for bucking logs. You use ripping chain. Commercial ripping chain uses a round or chipper style tooth and the top plate is usually ground to about 10 deg. For bucking logs you can use any tooth style, chipper, semi chisel, or chisel (square tooth), but the top plate is ground to 25 to 30 deg. It's analogous to how hand saws are sharpened differently for cross cutting or ripping. If you try to use cross cut chain for milling lumber it will leave a really rough surface. Worse, the chain will create spaghetti instead of chips and they will jamb up the clutch. The steep angle on the top plate of ripping chain creates a much smoother cut and chips that are easily carried out of the kerf. The downside is ripping chain cuts a lot more slowly and takes more HP. Everything is a compromise.
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(11-08-2018, 06:27 PM)Stwood_ Wrote: Look the butt over real good for black stain on a freshly sawn log. Stain from the nails works it way down to the butt.
If it has lower nails or barb wire in it, it will show in the butt.
Yes. A nail will take the edge off a chain or bandmill blade in a heartbeat.
I hit a ceramic insulator one time when I had my LT-30 woodmizer mill. I didn't cut through that one......
You are mostly right, if there is metal in a log it travels down towards the butt. But in the log I just milled that had those nails there was no black stain at the butt. It stopped somewhere between the nails and the butt, even though those nails were put in the tree when it was only 25 years old or so. I didn't count all the growth rings but it was easily more than 50 years old, so in 25 years that stain didn't make it to the butt. First time I've seen that happen. Another reason to get a metal detector.
John
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Didn't hit any nails milling this fall.....did "nick" one of the stops by about .050".
New band please.
Ed
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(11-08-2018, 07:58 PM)jteneyck Wrote: ... If you try to use cross cut chain for milling lumber it will leave a really rough surface. Worse, the chain will create spaghetti instead of chips and they will jamb up the clutch. The steep angle on the top plate of ripping chain creates a much smoother cut and chips that are easily carried out of the kerf. The downside is ripping chain cuts a lot more slowly and takes more HP. Everything is a compromise...
That "rough surface" that semi-chisel chain leaves behind is easily planed or sanded smooth. Also, we have never had trouble with "spaghetti" jamming up the clutch while milling oak, ash, walnut or even red elm. So, I use semi-chisel that is far more common and cuts much faster. Here is my even lower cost milling in action on a smaller but very usable ash log:
That's a Makita 6421 with a 32" bar and it had no trouble.
Rip to width. Plane to thickness. Cut to length. Join.
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(11-08-2018, 11:27 PM)EdL Wrote: Didn't hit any nails milling this fall.....did "nick" one of the stops by about .050".
New band please.
Ed
There were four, 2" adjustable square tubing backstops on the mill that I had.
I sawed into one of them one day, about an inch in before the band dulled and the head stopped moving.
Good machine. I had it ten years, cutting over a million recorded bd feet with it.
Steve
Mo.
I miss the days of using my dinghy with a girlfriend too. Zack Butler-4/18/24
The Revos apparently are designed to clamp railroad ties and pull together horrifically prepared joints
WaterlooMark 02/9/2020
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(11-12-2018, 07:58 PM)Edwin Hackleman Wrote: That "rough surface" that semi-chisel chain leaves behind is easily planed or sanded smooth. Also, we have never had trouble with "spaghetti" jamming up the clutch while milling oak, ash, walnut or even red elm. So, I use semi-chisel that is far more common and cuts much faster. Here is my even lower cost milling in action on a smaller but very usable ash log:
That's a Makita 6421 with a 32" bar and it had no trouble.
If that works for you Edwin that's all that matters. I got where I am today after many trials and plenty of errors.
John
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I'll probably never try to mill something that large but thanks for the very informative post. With the pictures, you make it seem doable for the average guy.
Telling a man he has too many tools,
is like telling a woman she has too many shoes.
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