Metal detector

[GarryW]

I had a batch of logs last week and managed to hit 3 screws which took out 3 blades.  :( :( :( With my LT25 it wasn't much of a problem since I could feel it when I got into metal. But with the new mill (LT40HDG25) I go right through, hear something and watch the blade start to wander. By the time that I stopped the head with one of the screws, I saw sparks coming off the ceramic disks and the blade was a bit warm.

Okay, what do you guys use to find nails, screws, etc. in the logs? ???  I've been using a Zircon stud/metal detector. For the price it is okay but too time consuming and only picks up stuff a little over an inch deep in the log. I've been thinking about the RENS P-4000, which for part time use seems like overkill. I did get a chance to use a metal detector for jewelry and such, that seemed to work okay but it didn't seem to go to deep into the log.

[Tom]

I have a Garrett detector (treasure hunting type) that I use on logs.  It reads a depth of up to 8 inches on a 16 penny nail.

White's Electronics makes three detectors in the 250 to 500 range that work good and have good depth.  If you are looking at good detectors to begin with then the extra money is usually spent on descrimination logic and stuff like that.  You don't need that when checking logs. You want to find every thing.

There are other manufacturers of metal detectors in the "hobby" field that are affordable and will do a good job

Don't be mislead by the term "hobby".  There have been many innovations in metal detecting since its initial use by the Army to detect mines.  The "hobby"  field leads in these innovations where the technology is being used in detectors  for security and other commercial areas.

If you have never used a good detector, find a reputable dealer who knows how to use what he sells.  It takes "hands on" training to appreciate the devices today.

I find that my sawblade will usually find the first nail so it must be the best detector, just a one time use device. :D

[Frank_Pender]

Garry, I have a RENS 4000.  I love it.  I have been able to find metal in a log up to 3' to the other side.  I figured that the cost of $1,395 has more that paid for itself in the last 4 years.  I have not had a problem with the unit at all.  I have heard tell that some folks have had a problem with the battery going gunnysack and it is very expensive to replace.  However, in the four years of my using this unit I have not had concern one.

[Brian_Bailey]

Garry,

 I use a Heathkit metal detector that I put together from a kit.  I don't know if the company is still in business or not.  I cut a lot of yard trees so metal is a concern.  It wasn't designed for scanning logs but it does an acceptable job.

 I agree with Tom about the learning how to use them.

 I had a customer bring a walnut log to my place for me to saw for him.  I asked about hardware?  He said, Not to worry, there's no hardware in it because I had so & so check it with his metal detector.  Well,  I happened to know so & so  and knew he spent a lot time searching for coins & etc. with his metal detector.  So I wasn't too concerned about metal.

 A couple days later,  I put the log up on my Sanborn mill and started cutting.  Second cut in after the slab,  I heard that sickening sound of a 5" wide band hitting something metal!  It seemed like an eternity for those 36" dia. cast iron wheels that the band ran on to finally stop.  All I could think of  was a ruined $225 band.  Fortunately my filer was able to save the band.  I had hit a 20 penny spike,  but the kicker was,  after I removed the log from the mill.  My detector  found a section in the log about 8"x 24" it went bonkers on.

 I called the log owner and told him what happened.  He had the guy come up with his detector and scan the log again.  All the time this guy is saying I know how to run this thing,  I use it all the time.  He scans the log, nothing.  I put mine by the log and it wails.  He starts to look flustered while he's adj. his detector,  then he blurts out OH SHOOT!  I had it set for non ferous,  flicks a switch an wam it starts wailing when placed by the log.  I could of killed him.

 Don't hesitate spending the bucks for a good detector,  they'll more than pay for themselves over time.

[OneWithWood]

I can see a metal detector in my future - whoo hoo another toy!  8)
Having never considered buying one before I am not up on the manufacturers or dealers.  Would one of you fine folk point me in the right direction(s) - just don't spin me like a top, I get dizzy easily ;D

[Frank_Pender]

Rens site is: www.Metaldetect.com

[GarryW]

Thanks for the info. It sounds like the RENS is a good unit and worth the $$$ especially for large logs. And the others sound okay if you get them set right and you get a better unit. And I do believe in that you get what you pay for, sometimes too excess though.

Brian -- wow -- Heathkit -- it has been 30 yrs since I put together one of their kits, I think it was an analog voltmeter and it still works too!

Do you guys always scan you logs or just depending where they came from (like a yard or along a property line)?

I think that I'll have to one of these soon but then I need to pay for oil for the winter and get a plow for tractor.

garry

[Tom]

Garry,

Those highlighted words in my post, #1, are links to the manufacturers site.  

When you see stuff mentioned in the posts it pays to pass your cursor over it to see if a link has been created.  If it is a link then it will become outlined when the cursor hits it.

[Frank_Pender]

Garry, if the timber comes from a home area yard of from some small patch of "farmer wood"  I always run the detector over the logs, unless I have one of those "senior moments".  :'(

[GarryW]

Tom,
  Thanks for the link reminder, but then I've been doing software for over 30 yrs and after a while it all looks the same to me.

Frank,
  By farmer wood, you mean an area in a field or around it, like the places where they like to put in the barbed wire? I'm still waiting to hit something really large like a horseshoe but only screws, 20p nails, and a few bullets so far.

[Frank_Pender]

Yes, those sorts of places as well as those real small plots of timber ground on plots like 5 acres or less.  Wait until you his something like a 3" insolator.  You will need a flak jacket.  Or, how about a power company anchor bolt that is 20" long and 3/4" diam..  One time I chased a piece of hop wire for six feet in a 3' diam. Black Walnut.  The log looked like a big hunk of Swiss cheese when we finished excavating for metal.  They had used the tree for an anchor post for several rows of hops back in the '30's.  It is all fun stuff.  Almost like a treasure hunt at times.  But, the metal detector is a fine tool, if I would just remember to use it more often.  :'(

[Tom]

Well Garry, there I go preachin' to the choir.  :-[

I think I intended to address Roberts post rather than yours but had a lapse.  Thirty Years, Huh!  Not much many around here can show you.  Heck, I'm still learning this stuff.  It's not much like any bits and bytes I've ever shuffled.  Pretty neat though.   :P

Franks got a pretty good handle on when to be leary of tramp metal.  

There is something I listen for from a customer that makes me get my detector out. "Nope, No metal in that tree.  I've lived there 20 years and nobody's ever touched it". :D

[Brian_Bailey]

 Yard trees always get scanned.

 Logs that a customer brings to me, well, it all depends on where they say there cut from. Last week I was sawing some E. Hemlock for a guy. I've done a lot of sawing for him and never had any problems with metal.  I was rolling the last log to the mill when I noticed a nail sticking out near the butt.  The metal detector found several more,  so you just never know.  

 Logs that I get from the loggers I seldom scan.  Once in a while I'll hit something, but it's mostly lead bullets.  

 One thing a metal detector will not find is nylon rope.  I was sawing a walnut crotch that had a piece of nylon rope completely hidden in it.  Nylon doesn't cut well but boy does it stretch.  I had a few tense moments until I realized what was going on!  

[C_Miller]

I agree on never knowing when to run the detector.

Had one customer have me saw out a yard full of spruce(3000bft)and hit nothing. Very next customer dragged trees out of the woods and two had nails.

 The best mental detector I've used was a customer's that had spent $5 for it at a yard sale.

C

[woodman]

Glad to see you joind Gary.

[ARKANSAWYER]

  Customer buys the blades and scans if they want to.  I saw, change blades and write bills.  If I get logs from tree service or home owners I do not pay till the sawing is done and I pay if I make any thing.  Time spent detecting would not be profitable for me.  The small stones in my area are full of iron oxide and set off the detectors just like a nail.  I think that I may get one for play and finding parts dropped into the saw dust.  But for $20 per blade and the few I lose every year do not know that the cost and time would be worth it.  Those new hard deck screws can really mess up a few teeth before you get through.  I have some blades I use for rootballs that are missing a few teeth and I use them when I suspect metal.  0.055's do better at cutting metal and living then the other blades.  I have not tried a colbalt blade yet.  
   Frank,
  Have you gotten metal into all of those blades at the same time?
ARKANSAWYER

[Steve]

I thought I had seen trash in logs, but not until I milled a few old Mango trees did I really know what "trash" was! Lots of old square nails along with anything that anyone must have leaned against it in the past 100 years. At least one dog chain around the stump. Hopefully low enough so the chainsaw doesn't find it when falling the tree.
The worst though are the rocks, buried in the crotches of the trees after generations of rock throwing to dislodge the Mango fruit. Fist sized, hard, volcanic rock, ugh!!!
I have a set or three of "Mango teeth" just for the butt logs.

[Tom]

Without getting into things I've hit, I'll tell you about a problem I may cause someone.

That big Oak tree with the rope swings in it that Charlie and I played in has a Block (as in block and tackle) in the first big crotch.  The last time I saw the tree, the only thing that was showing was the tip of the iron hook that was on the top of it. It had enough showing that it looked like the knuckle of your finger if you bent your finger.   The Block is as big as my head and the hook is iron bigger than my thumb and it would not fit in my open palm.  

I hope someone doesn't put that tree on a mill.

I can hear it now,  "Yep, no nails in that tree.....I've lived here over 30 years......." :D

[Frank_Pender]

I did not follow my own adice today. I hit 4 d### jacket 30 plus calaber  bullets and then to top that off I thought that the stain was from the bullets but NO, I discovered 2 20 penny nails that must have been used to hand a target on the tree.  Blast! ???   I called the log owner and asked him if he wanted a neckless or a belt out of the ruined teeth. ;D  There were 18 of them shot, at the rate of $3.65 each ($65.70)

[woodman]

Tom i' have
 herd that one befour zing zing zing zing  
 30 dollars please would you like me to keep cutting i will put on a new blade.

[Tom]

Here is a picture of a Catface in a turpentine plantation.  This is one of the few times you will find nails in the woods.   The turpentine cup is nailed to the tree below the top of the catface.  As the tree sap crystalizes, the catface is cut anew at the top and the cup move up to the new cut leaving nails in the catface.  When the tree is cut for lumber or pulp, it is "jump cut" or the butt is cut off above the catface.

Catfaces are valued only for kindling (fatwood, lighter, lightered) even though some small mills will try to cut them.  they are so full of crystalized sap and nails that it isn't very economical to saw them.

[GarryW]

Well, I finally broke down and bought a RENS unit. I got a used P-4000 from them with the 2 year warranty and a bit less than the normal price. It just came in a few minutes ago. 8)

Since its raining outside I tried it out in the kitchen, sure enough it found the screws and nails in the floor, the screws and drawer slides in the cabinets, and anything else that had metal in it.  

Now, I need to use it on those large sycamore trees.

garry

[GarryW]

geez, I almost forgot to thank all of your input. It was really helpful. Now, I just have to remember to use it. :D

[Den Socling]

I used to work with a couple metal detector companies. RENS was one but I worked with MDI more. Mostly, I debugged their big log scanners but I sold a few hand-held units also. MDI used to sell what they called the 2000. I think it was around $500. I don't think they built it but I could be wrong. It was great.

One time I stopped at a mill and was greeted with "What do you want?" I told the guy that I wanted to show him this metal detector. He took me to a pile of "suspect" logs that had been kicked out because of stains. He said I had two minutes to demonstrate and then get lost! I guess it was three or four hours later that I left. We went though the pile, he cut out the metal, sawed what was left, showed me his mill and kilns and I departed like we were old friends. yep, small sawyers with band mills need a good hand-held detector.

last time I went to MDI for a 2000, they were discontinued. The replacement was a 2100 for $1000. This was still a lot less than RENS.

The 2000 could find an 8d nail buried 13 inches in a log. I don't know what the 2100 can do or even if MDI is still around. I hope they are as they were a good group to work with.

[FeltzE]

I have a very good metal detector, but am too lazy to use it. But I do sharpen my own blades : So... I am not too overly concerned about dinging up an occasional blade. IF I get into a situation where there is a lot of tramp metal in a log the log ends up as firewood!


Eric

[Mesquite Man]

What about the Lumber Wizzard?  Does it work?  They are listed in a number of the woodworking catalogs for $90.  They claim to "scan any size wood" and "six inch wide scanning area".  Do you think this would be adequate for a hobbist?

Curtis

[Jeff]

Seems to me Tom won one of those. He should know. I think they are meant more for finding a nail or fleck of metal in a board you are working with versus a log.

[Tom]

Right-0-Rooney, Jeff.   I won a Little Wizard but I don't think it is the same machine that he is talking about.   Mine is ok for scanning small areas like making sure that you dug out all of the nail.  I still use my Garrett to scan logs and to make sure I feel good about the board.   The Little wizard is ok, if you have it with you.  I keep it in the glove compartment for a backup. It is also a voltage tester and stud finder and works off of one 9 volt.

[Curt_in_eastern_NC]

Hey Guys, I'm just now becoming interested in the sawmill scene but have been a hobbiest metal detectorist since 1984. So I have read with interest this string of replies. As far as the so called "hobby" metal detector being used to find tramp metal...it will work great if you keep a few things in mind. These things will also apply to the industry's dedicated metal detectors I would assume, so here's my little bit of input on the matter.

Everything in the circuitry of the "hobby" MD is geared towards rejecting all ferrous materials or at least making the sounds and signals that will indicate ferrous items. This is because most detectorists (except for the "relic" hunters) are searching for non-ferrous items such as silver and gold jewelry, old copper, silver, or GOLD coins, or anything with precious metals in them. Iron and steel cannot be totally rejected but the machines can be set up to enhance its capabilities to find this stuff. Set the machine in its All Metal Mode. This can be a separate setting or sometimes the pinpoint feature is an all metal mode to aid in narrowing down the area the sought item is in. For most machines this is also the deepest seeking mode to be in and without doubt the only mode to be in for this job. At least make sure the discrimination feature is either off or turned way back. It was no surprise to me the above referenced hunter missed the nails because of the mode he had accidentally left the machine in. BTW, the more discrimination you use, generally the less depth you will have anyway.  As a rule the larger the coil the deeper the machine will seek. It's a trade off, though, because the larger coils also tend to "drop" smaller and smaller items the larger the coil becomes. A simple aspect to always be aware of, is that the detector is searching everything within its cone-shaped searching area. This means to be aware of what's in the background of the log you are searching. There could be an aluminum pop can buried a couple of inches in the ground below the 12 inch log you're scanning. The machine will probably pick it up. There are several stories circulating within the MC hobby of someone forgetting they put on their steel toed boots to hunt in. They stayed puzzled because of the strange signals they were getting that were not there yesterday.  Chains or hooks inadvertantly left on the log will surely be picked up by the machine. Your own jewelry such as watches and rings could be picked up. Make sure you "scrub" the log to get every inch of search depth available. It never ceases to amaze me of hunters who keep the search coil 6-8 inches above the ground when hunting. And then swear the machine is no good. ;D  One last note is just an opinion of my own. For this type of use, the more expensive machine usually will not mean more depth for finding tramp metal. The expense comes from all the discrimination bells and whistles that are necessary for the MD hobby. All you want for logs is the all metal mode and paying for the extra discrimination features would just be a waste of money.  I hope this helps.  

[Tom]

Curt, good post.

That's what makes this forum so interesting is the varied interests of the members.  You may not be into sawing very much yet but you certainly earned your wings with the metal detector information.  You don't have to walk the straight and narrow to be a good membere here.  We even put up with Charlie and his super-duper, hi-fa-luttin, craftsman chainsaw with the high compression air filter and quick-shift choke.  :D  He does turn some pretty bowls though. :P

Sure good to have you around, don't be a stranger now, ya' hear?

[DanG]

Great post, Curt. 8)  Lots of good info there.  I had already discovered the folly of hunting with the steel toes, and was about to mention it, when I read your post. I have to wear them at work, so I most always have them on. You can use your MD while wearing them, but it'll make you walk funny. :D

[Fla._Deadheader]

Something else to consider. The Garrett Co. has waterproof detectors that work on the pulse induction technology. They get the best depth and we have sold used ones for $200.00. They retail for near $1000.00 and can be tossed about in yer truck and left out in the rain. They are near bullet-proof. Check ebay or some of the classifieds for metal detecting. Shouldn't have to spend over $200.00 to get a very good machine. We used the Garretts for years, detecting the wrecks here, and they really NEVER went bad. They have re-chargable batteries and last for 2-3 years when you use them a LOT.The model I am referring to is the XL-500. We used to repair them also. 1 or 2 different chips would fail or the coil would get scrubbed through and leak and we kept them in stock. 30 minutes and yer back in the water. They were used for YEARS by the pros until better ?? machines came out that would find GOLD better.

[Curt_in_eastern_NC]

These are metal detecting related sites that have a separate classified section where anyone can advertise their wanted/for sale items. If for nothing else, it will give you an idea of the going selling prices for used metal detectors. ;)

Ever wonder why metal detecting is such a popular sport?  Ever sell a button off a coat for $400 and up? That's a very real figure for many Confederate Civil War relics.  Also, did you know that there was 10 times more coins lost or hidden than there is now in circulation.  I can see why sawmilling and metal detecting are very similar. Just as in MD, you never know what the next beep will reveal in the ground, so also, each board that comes off the mill has its own little secrets to reveal, too.  Happy Holidays to all.

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