One of those days!! Nail days.

[DocGP]

Finally getting around to one of the big pines in my yard that the storm blew down this summer.  Top 2 logs went pretty well with a 10 deg double hard, but it was getting dull, so loaded the butt section...34" at base and 14' long.  Biggest I have had on the mill.  

Well, put a new Turbo 7 on and fired up.  I promise the debarker didn't hit 6" from the end of the log, but that was far enough to miss a big stinking piece of slag that hitched a ride during skidding!  Sparks, grinding, and blade climbed like a mountaineer!  Well, crap.  Next T7.  That one made it about 5 minutes and "Zing, Zing"......two nails.   Dug them out, changed again.  Made it about 30 min this time.  Thought I was home free.  Nope, Zing Zing.  Two more stinking nails.  I had been told that the Bi Metals would take a decent metal strike and keep going, so thought I would make one more attempt at finishing this beast.  Got down to the last 6X6" cant, and yep.  Zing, Zap, Zing, Zing!!  Four freaking nails in a row!!  Still cutting, but waving badly.  I had enough.  

That last can't will be my chock blocks.  Going to use the bimetal to finish cutting my flitches and then retire it too.  It put up a valiant fight, but 4 that look like 16 penny in a row were just too much.  

At least the lumber was worth more than the blades it cost me, but ouch.

Doc

[Tin Horse]

Yup. I've had a few of those days. I've got a good customer that brings logs for 1" lumber. He owns a fencing business. So much of his stuff is fence line clearing. I learned early on to check his logs for metal and he pays. I've got a hemlock log sitting up there ( similar to your experience) as a reminder to myself and show people. When the hits start,often more follow. They come off the mill. Too much time and damage. The odd one I may go back at another day on my time with an old blade.

[Maine Miller]

I am very new at this, having just bought my LT35 in September, but a friend that has been sawing for years told me to use a metal detector on any log I didn't know where it came from, or was cut from someones yard. It has already saved me one blade.

[GAB]

DocGP:
Was there any blue or blue spots on the bottom end of the log?
Could you tell what the material of the nails were?
The reason for my questions is that just before thanksgiving I hit metal in an ash log that I did not see any blue in the bottom end and the hook that was in the log I thought might have been stainless steel.
In my case had I been 1/4" higher with my cut I would have missed it entirely.
GAB

[Magicman]

SYP logs will seldom show any indication of metal other than hard yellow/orange  pitch around the offending object.  Blue is caused by iron reacting with the tannic acid in hardwoods such as Oak.

I will/do not use any blade other than DoubleHard because the customer pays for metal strikes which is $30.  Specialty blades such as BiMetal or RazorTips would easily cost 2-3+ times that amount which would be unsatisfactory to the customer.  He is not concerned by how many bf I can saw before sharpening a blade because that is my cost.

I hit three nails in one log on my last sawing job @ $90.  He could have been very dissatisfied if the blade charge had been $150 for Bi-Metal or $270 for RazorTip Carbide.

[GAB]

SYP logs will seldom show any indication of metal other than hard yellow/orange  pitch around the offending object.  Blue is caused by iron reacting with the tannic acid in hardwoods such as Oak.

Mr. Davis Sir:
My sawing experience with SYP is el zippo.  If we have any here I have not seen it.
Do you know if eastern white pine react the same way as SYP?
You wrote "iron reacting" - is stainless steel considered in the iron catagory?
Does ash have this tannic acid you speak of?
Hope you enjoy your Christmas contest winnings.
Gerald

[Magicman]

I will send the "el-zippo" back on White Pine.  I do not recall ever hitting stainless steel in anything and I have never hit metal sawing Ash.

Happy New Year my Friend, and Yes, I intend to enjoy that Maple Syrup. 

[appleseedtree]

Every log I get comes from someone's yard. Front yard side yard back yard or way back yard. Since I don't carry the metal detector with me I've gotten in the habit of guessing and gambling when cutting the logs. Most of them are not very good but some are premium. 
When the trees are near the back door the chance of having nails is about 99%. Front yard is better, and way back is also good. I've found that most of the time the nails are at the most comfortable height to swing a hammer, but sometimes there are lights at 10-12' and occasionally a tree house which means dozens of nails, and if I'm guessing where to cut the log I'll look at the house and landscape first and waste the best and lowest 6' if I can get a log above that. If you see root flare in a log you can speculate there'll be nails at about 5'. 
All species show some indication of nails, but very subtle on all pines and some others. Oak of course is the most reliable for showing as the stain travels up and down the log a couple of feet and it gets brighter once the wood is exposed to oxygen. 
Walnut trees are another story. The best species is also the most suspicious for metal. An old sawmiller near me says that even when a walnut comes from way up on the mountain out in the woods they suspect it has nails in it as the old timers used to drive nails in to make them bear more nuts. HA!  You can't have nuthin!
A metal detector can certainly be worth the money if you can manage it, otherwise look at the outside carefully for scars or nails sticking out, check the ends for any color at all and then guess! 

[Stephen1]

I don't mind hitting nails when it is a customers logs, they pay for the blade,  but I hate hitting nails when they are my logs. 
I have been runnng the bimetal blades, nicer cuts, but  am thinking on going with a double hard or silver tip  1.5" blades thinking they will be a little less costly but still give nice cuts. , 

[DocGP]

MM,
Yes sir, I was just sawing for me, or I wouldn't have used the BiMetal.  I am impressed with the damage it took, but 4 were too many.  After a single nail, the DH's were done, the one that took out more than one was really trashed.  The nails I pulled seemed to be typical common nails.  The 4 that got the BiMetal I think were 16 penny.  The main discoloration that was present was a dark brown ring around the nail that wasn't an inch in diameter.  Nothing like the oak stain.

Doc

[Chuck White]

Yard trees have been known to be blade-killers.

Lots of people will put up birdhouses, birdfeeders, signs, flag hangers, etc, and the tree, over it's lifetime will grow around all that stuff.

[SawyerTed]

Last year I bought a load of white oak logs that came from a home place.  I had asked the tree cutters to cut the butt log to 16'-6". I was anticipating metal and my purchase offer reflected that. My intent was to cut the bottom 6' off and make firewood which I did.  

It would have worked but someone had built treehouses, put antennas in the trees, hung swings and clothes lines higher up on the trees. I hit screws and nails, screw eyes, wire, chains, u-bolts it was awful.  I finally got through the logs.  In the end I did better than break even but my profit was decreased by a couple hundred dollars.

The landowner wanted me to buy more logs from the same location.  I told him I wouldn't take them if he gave them to me. 

[Tom the Sawyer]

Where I am located (KC metro area), most of the logs I mill have been in close contact with humans at some time.  Earlier this year I had a phone conversation with someone who was considering buying a mill and asked a lot of questions about hitting metal in logs.  I'm a bit of a detail guy so I thought I would check my data. 

For the first 500 logs milled in 2020, I replaced the blade due to striking metal (usually nails) 20 times.  It was actually 17 logs that had metal (3.4%), a couple took out more than one blade.  3 blades were destroyed, the others were resharpenable.  Average yield was 139 bf before the strike, although several were on the first pass on the log, or after replacing the previous blade.

YMMV, of course.  

[Patrick NC]

I am very new at this, having just bought my LT35 in September, but a friend that has been sawing for years told me to use a metal detector on any log I didn't know where it came from, or was cut from someones yard. It has already saved me one blade.

I've tried a couple different metal detectors with pretty good success, but in the end I find that the most accurate metal detector is a brand new blade!🤣

[terrifictimbersllc]

Eyes on the log is a pretty good detector too.  

Not infrequenty, a blade is trashed by from metal the customer or I could have seen if we looked carefully first. 

[Patrick NC]

 
My brother came by today to get some 3/4 pine boards to fix his privacy fence. It had been way too long since I'd hit anything in a log.
 

 

 I got this screw dig out, changed blades, and ran my metal detector over the log. Can't find anything else in it. So I fire up the mill, cut two more boards and found another one. 

 

 When I saw the heavy pitch on the previous board I should have stopped and ran the wand back over it. 

 

 

 2 blades makes a pretty expensive "free" job. 

[DocGP]

If one runs their own sharpener, can those blades be run a few extra rounds on the grinder and be saved, or is it better just to toss them??

Doc

[Stephen1]

I would throw those blades out. I have tried to save blades, but it can be hard on the grinding wheels.

[moodnacreek]

Those big pine yard logs should not be cut at 14' . When you find metal you need to cut above it and get a 8 or 10' log. While I can't explain it ,I will tell you that 12' or 16' is what works in soft wood.  I metal detect almost every log that comes in. Hitting metal on sawing day is too much of a setback.

[Patrick NC]

If one runs their own sharpener, can those blades be run a few extra rounds on the grinder and be saved, or is it better just to toss them??

Doc

Those blades are junk. No saving them. 

[SawyerTed]

The time and energy to save some blades after a metal strike isn't worth it.  Then there's shortened life of grinding wheels trying to save a $17.00 blade.  I do save a few but the damage is minimal.

[terrifictimbersllc]

If one runs their own sharpener, can those blades be run a few extra rounds on the grinder and be saved, or is it better just to toss them??

Doc

Those tips look fairly rounded over and a lot of that in a row of teeth.  I wouldnt try to save those. 

When I look at blades which hit metal and see that there will be more than 3 or 4 grinds, it goes in the scrap pile.  Each grind being 5-10 thousandths, that will be when more than about .030" needs to be taken off to reform the tooth.  Can measure it with a calipers or guess at it.

[caveman]

John and I started sawing a fat slash pine that should have yielded five, 3 5/8" cants today and I smashed into some metal. We debated for a while if it was a chain, or something else. It turned out to be an eye lag bolt. As a bonus, there were several more nails in the log. We found all of them. This log should have yielded well over 50 2x4's. I think we got 43 out of it after three hits and blade changes. 

 

 

 

    We had all sorts of tools out there trying to extract the eyebolt. The last nail strike did not seem to hurt the blade and we sawed 20 + 16' 2x4's with it out of some nice longleaf. The weather was perfect today and the wind was at my back. It was a good day. 

[mart]

A couple of years ago I was sawing two nice spruce logs. Both 16 foot from the same tree and green. Unusual for this area with all the beetle kill. The first log, the butt log, was fine but about 14 feet into the second log I hit two of the double head scaffold nails. Both side by side. I asked the owner about where he got the logs and if they were yard logs. They were from an undeveloped area. No houses for a long ways. Area was being opened up for a cabin build. The only thing we could think was there must have been a tree stand in this tree and the nails were for hanging a bow or rifle. We figured they were about 31-32 feet up the tree. The owner said there wasn't a limb on the tree for a long ways which confirmed  my thoughts that it must been a tree stand tree.