Sawing speed as you hit a nail

[Brad_bb]

So I've been re-milling reclaimed beams for the last month.  I was new to milling when I started.  Although we de-nailed the beams, every once in awhile we hit one that was missed.  I'm noticing that if you are milling slow and cautious and you hit a nail, it screws up the blade and it dives for sure.  But if you're moving at a good clip and hit a nail, about 30 percent of the time you can continue sawing albeit a rougher cut.  I'm thinking that with the faster feed speed it sometimes cuts through the nail with fewer teeth, thus screwing up fewer teeth allowing you to continue on that blade sometimes.  Anyone else think this?  This is on an LT15go. 

Another question.  When you do hit a nail and your blade wants to dive, is that blade usually resharpen-able by Woodmizer?  Or is it toast more of the time?

[terrifictimbersllc]

This could well be exactly right and going fast maybe the right way to go if you know the nails are smaller and at right angle, and perhaps cut nails.  But I view the issue of hitting nails in valuable wood as not saving the blade but saving the wood.  If going too fast one might not be able to stop before the blade climbs or dives.   Sighting the kerf, on one knee if necessary (I'm at a remote mill), making sure the blade is still cutting straight, is the way to go.  Stop before the blade deviates, back out or cut it out, and change it. 

I think a metal blade will usually be rejected by WM.  Tips rounded over at all, or you can feel the metal curled along behind the hook of the tooth, they won't sharpen it.   I may not either if I judge its more than two passes around the grinder, and before that cleaning with a file so as not to damage the CBN wheel. Too much work and the customer has already paid me for the blade.

P.S. when I'm chain slabbing, I can feel the first touch of the chain on metal.  Then I push hard, hoping to power through it quickly with fewer teeth.  Also if I don't power through it, the slab's not getting cut. 

[ely]

I think you are correct in your statement to an extent....that meaning regular type nails, if you hit screw nails like in pallets and dry wall screws no way it is going to continue. I have found that if you will inspect the band after you hit a nail or any metal you will find the teeth has a small curl of metal on the face of each tooth...take your pocket knife and remove it, most times the band will cut fine after that.

[customsawyer]

I have hit my fair share of metal. If it is just a few teeth that are messed up then you can sharpen them. That blade might leave some small lines on the lumber but not to bad. If it is 10 teeth or more that is messed up you can still sharpen it to where it will cut but it will leave much larger grooves on the wood. These blades I set to the side and use next time I am cutting and I know I am going to hit metal. I don't know what the standard is for WM on rejecting a blade.

[terrifictimbersllc]

I have hit my fair share of metal. If it is just a few teeth that are messed up then you can sharpen them. That blade might leave some small lines on the lumber but not to bad. If it is 10 teeth or more that is messed up you can still sharpen it to where it will cut but it will leave much larger grooves on the wood. These blades I set to the side and use next time I am cutting and I know I am going to hit metal. I don't know what the standard is for WM on rejecting a blade.

Ten teeth  : :  I put the blade on the floor and step on it.  But your blades cost more than mine.

[customsawyer]

I also have over 250,000 bf of metal logs to saw for the large mill I cut for.  ;) Any blade I have that is in rough shape can still be sharpened enough to cut some of that. ;D

[justallan1]

The first time I hit a nail it did make it through the nail, but left my blade "marking" real bad. I got down level with the blade, found the bent teeth and took my Leatherman to them. I was able to get a couple close and snapped 1 off, but figuring the blade was already toast and that I was sawing corral boards I kept going and used it anyway with it marking a little still. (cows don't care what your cut looks like)
If it were something other than corral boards or I'd planned on selling it, I would have changed it right then.

[Jim_Rogers]

When I send my blades in to be sharpened by WM Resharp and it has hit metal, I turn the blade inside out. That way they know that somethings up with this blade.
Sometimes it get sharpened, sometimes it gets replaced. It all depends.

Jim Rogers
PS, that inside out trick is with resharp in NY. I don't know if other resharp places do that or not. You may need to check with the location where you send them.

[Magicman]

I tag my blades that have hit metal.  Some get resharpened and some do not.

Look at the blade carefully after you hit a nail.  There is often a curl of metal attached to many teeth.  This can be removed with a knife blade before sending it to Resharp.

I doubt that I have ever been going slow when I hit metal.

[Brad_bb]

I was trying to see what worked better, to go slow when you suspected there could be something and trying to back off when you touched it, or going faster and ripping through it.  I'm not turning these beams into boards, I'm refacing and re sizing them from their current dimensions (9.0-11x 9.0-11)  down to 8X8's, taking out any twist or bow as I do it and making them dead square.  I make a pass with the band mill, and then follow up with the beam planer(MP100).  It's not the fastest process, about 2 beams per hour on average, but I think it will be worth it to me. It's dry and stable.  Those are empty nail holes you see in the foreground.  One or two faces of the beam typically have that, sometimes it gets removed when resizing.


 

[logboy]

P.S. when I'm chain slabbing, I can feel the first touch of the chain on metal.  Then I push hard, hoping to power through it quickly with fewer teeth.  Also if I don't power through it, the slab's not getting cut.

I scan with a metal detector on each pass with urban logs. If its a high dollar slab, then I mark where the nails are and try to cut through them with one chain, usually a worn out one. Then I put on a sharp chain and finish the cut. Worst case scenario (usually rocks) I take the slabber off and cut from the opposite direction to meet the cuts.

[Chuck White]

I think you are correct in your statement to an extent....that meaning regular type nails, if you hit screw nails like in pallets and dry wall screws no way it is going to continue. I have found that if you will inspect the band after you hit a nail or any metal you will find the teeth has a small curl of metal on the face of each tooth...take your pocket knife and remove it, most times the band will cut fine after that.

Done that quite a few times, and it's true, most times it will still cut good!   

[terrifictimbersllc]

I think you are correct in your statement to an extent....that meaning regular type nails, if you hit screw nails like in pallets and dry wall screws no way it is going to continue. I have found that if you will inspect the band after you hit a nail or any metal you will find the teeth has a small curl of metal on the face of each tooth...take your pocket knife and remove it, most times the band will cut fine after that.

Done that quite a few times, and it's true, most times it will still cut good!   

Never knew that, seems like a better alternative than backing out and putting on another blade, to finish the cut.

[drobertson]

Yea I have noticed that faster through the hardware is better than slower, it also, if possible pulls more dust off as well,  hit the back supports on some short logs a few weeks ago, just fuzzed them but heard that dreadful sound, knew it just before but powered through,, and did finish the cant with minimal marking caused by hitting, too bad this is not always the case, ;D  the dive early in the log or cant kinda stinks,

[GAB]

So I've been re-milling reclaimed beams for the last month.  I was new to milling when I started.  Although we de-nailed the beams, every once in awhile we hit one that was missed.  I'm noticing that if you are milling slow and cautious and you hit a nail, it screws up the blade and it dives for sure.  But if you're moving at a good clip and hit a nail, about 30 percent of the time you can continue sawing albeit a rougher cut.  I'm thinking that with the faster feed speed it sometimes cuts through the nail with fewer teeth, thus screwing up fewer teeth allowing you to continue on that blade sometimes.  Anyone else think this?  This is on an LT15go. 

Another question.  When you do hit a nail and your blade wants to dive, is that blade usually resharpen-able by Woodmizer?  Or is it toast more of the time?

Nails!  Try 1/2" lag bolts.  You do not have to make any decision other than to change the blade, and ask the customer what he wants to do.
Gerald

[bandmiller2]

Theirs truth in what brother Brad says. Its hard to make a sweeping statement because it depends how the saw hits a nail the best angle is 90 degrees all the rest get worse and really mess with your set. After you hit a nail check the band usually you will find several teeth bent with a small curl of metal on the face of the tooth. Take your pocket knife and flip the curl off, check the set and adjust with pliers. Most of the time you can continue if the cuts are not critical. Frank C.

[Magicman]

I understand what Brad is saying, which is why my response was more straight forward.  I am not going to slow down if I suspect nails, because I am not sawing if I suspect nails.  A metal detector, electric drill, and nippers will remove nails.  A hole drilled beside rusted nails will not deter from a beam's beauty.

[Brad_bb]

Agreed MM.  I have had some that the metal detector is not picking up. We've gone over it several times and not found it until we hit it.  This is more often the case with 1)this one type of broken off screw and 2)a very rusty nail.  Those broken screws, we pulled them out, and even with it sitting on to of the beam, will not set off the detector.  I'm going to send them to Lumber Wizard.

[beenthere]

I understand what Brad is saying, which is why my response was more straight forward. I am not going to slow down if I suspect nails, because I am not sawing if I suspect nails. A metal detector, electric drill, and nippers will remove nails.  A hole drilled beside rusted nails will not deter from a beam's beauty.

Priceless...

[shakebone]

If u cut a bunch of reclaim try a bi-metal blade , the worst thing I've hit was a ceramic fence insulator buried in a large white oak ! 

[scleigh]

I've cut a lot of nails, like everyone else, sometimes the blade will cut for a good bit longer but leave a rougher cut.
I was cutting a walnut log for a guy, it was a yard log and we had discussed the possibility of metal. We hit a few nails and kept sawing until we had to go to a new blade.
We got 4 nice live edge slabs and a beautiful mantle when we hit something that totally ruined the 2nd blade. Wasn't sure what we hit.
A friend came and cut all my slabs for firewood and brought this back to me:


 

The horse shoe was in his wood stove!!!! You can see the cut on the bottom part of the shoe.

[Chuck White]

I've often wondered, how much stuff (metal, etc) might be left in slab wood, or in the middle of a 2x6!  :-\

[Magicman]

A black streak and then metal detector verification has indicated that I have been "lucky" a couple of times, but more often....not.

[scleigh]

I was pretty sure metal would be present in the walnut log that contained the horse shoe. The customer was aware of the blade charge and was ok with it, said it would be cheaper than the Alaskan mill he had been considering.
After sawing was complete, everyone was satisfied. I expected a few nails, but not a horse shoe.

[bandmiller2]

Farmers are the DanGest ones for hanging hardware in trees. They don't want to leave any metal on the ground where they mow. Old tree lines around fields always have tramp metal and old fence wire but also the nicest trees. Frank C.