Carbide for circle mills

[Ron Wenrich]

Client is currently running normal steel teeth on their vertical edger and head saw.  There will be a whole log metal detector on the infeed deck.  This will minimize the trash metal, and hopefully eliminate it. 

I'm looking to minimize the maintenance on the teeth for the workers.  Its a learned thing, but I'm hoping to sidestep it by going to carbide.  I'm not getting any life out of the steel bits. 

I'm wondering how many guys are using carbide, and how much more life you get from the bits.  Logs will be debarked. 

Also, is it better to take the bits out and send it to a shop for sharpening or to do it in house.  There's a carbide saw shop nearby, and I'm thinking it might be cost effective to remove the teeth and send them out to be sharpened.  Trying to educate the sharpening process may not be as effective.  A little data would help me in doing a cost projection.  I have no experience with carbide.

I know Meadows Miller said he was having good luck with carbide.  Any others?

[GeneWengert-WoodDoc]

If you take the teeth out, when they must go back, the same shank must go into the same location in the saw that the shank came from.  Otherwise, the tension will be changed.

We tried carbide a long time ago.  We did not like it because the carbide on the bits seemed to chip easily. I then learned that carbide is very brittle, but that Stellite is not quite so brittle.

[Jay C. White Cloud]

This is definitely outside my wheelhouse, I would defer to Gene on this one, but I am also a stone carver, and most of my bits are carbide and really take a pounding.  When speaking to a Smith about carbide, I learned there are hug differences in grade and type.  The type in our carbide chain saw would seem to fill your need.  Perhaps reverse engineer your carbide type and see if you can get that type on to your saw blade.

Regards,

jay

[Ron Wenrich]

I don't think changing a bit is going to change the tension.  You change bits quite a bit during normal sawing.  Swapping shanks would do that.  Were you using the claw type of carbide?  That's the one that had the tooth and shank combined into one piece and you would take it out and get it retipped.  That I can see not changing the tooth/shank placement.

As for chipping, Arsaw has some that are supposed to be able to take a few hits by nails.  Seems like the technology might have increased where its actually a good product.  That's why I'm asking the questions. 

[beenthere]

Ron
Member Peach at Menominee Saw might be good to talk with about the latest that is available, just thinkin....

[Jeff]

We tried using carbide one time in the vertical edgers. Even sawing aspen, we'd continually break the carbides off. I think because of sawing speed in the soft hardwood, and the shock of hitting a knot would do them in. Always thought it would be nice to have edger blades stay sharp for a long time. I got to where I'd not try to sharpen edger teeth, just take them out and use them for spares in the headsaw where they could easily be sharpened.  Just changing bits or position of bits in a headsaw is not going to mess up your tension. If it did, you would have to have at least a half dozen back up saws and a whole passle of money.


Passle is not in the dictionary??  :-\

[Ianab]

My only experience is with the smaller blades on Swing and Twin Saw mills. Here carbide is pretty much used exclusively. I know there are different grades, and it's a trade off between hardness and toughness. The really hard carbide keeps an edge longer, but will shatter like glass if it hits something, The "tougher" grade wont hold the edge quite as well, but is less likely to chip.

I'm wondering if it's the extra power behind the bigger mills that causes issues? On our smaller mills we need to slow down in knotty wood, and keep the cutters razor sharp as we don't have the power to charge though anything with a 1/2 dull blade.

Depending on what you are cutting you might be sharpening the blade every couple of hours, but this is done with a little hand held grinder with the blade in place on the mill. It's something that only takes 5 mins, and you should be able to teach it to someone in 10.

It might be more practical for the smaller edger blades, and weld up a jig so the blade can be sharpened in place? Usually the carbides are welded in position, but there are also removable tip blades which are easier to "re-tip" in the field. I have a couple of them with my new mill.

Ian

[tyb525]

Carbide can't be made as sharp as steel, supposedly. I know I've heard people say the carbide chainsaw chain cuts like a dull regular chain even when sharp. I think stellite is a good compromise between carbide and steel. Not as brittle as carbide but much more durable than steel.

[lyle niemi]

Dad usta use high speed steel bits, dont know if they are still available?? The next time I order teeth they will be stellite bits

[woodyone.john]

I concur with Ians experience but wonder if on an edger the blade approaches the wood at a different'angle'. in swing and other 'log on ground' arrangements the blade starts to work on the deep edge of the board so has a gentle introduction to the wood rather than hitting it[ if i am making any sense] maybe if you could lift you in/out feed table on the edger to be cutting on the top of the blade you wouldnt get the same shock loading. cheers john   

[GeneWengert-WoodDoc]

Passle used to be in the dictionary, but they took it out (at the same time they took out gullable) and replaced it with passel (or gullible).

...doesn't make sense to me, but worth a try.

[Jeff]

A vertical edger's angle of attack would be similar to a swingmill's.

[Axe Handle Hound]

I've never run a circle mill  and i'm lousy at math but maybe someone here can tell me why carbide tablesaw blades work like a dream and rarely ever break but carbide edger blades do? I can cut the hardest wood and knots possible with my tablesaw blade without a single problem.  Why is it different for a mill?

[Bill_G]

We tried running carbide in the headsaw once , even with debarked logs , there was a lot of chipping . Finally started using sichrome winter bits year round and loved them .

[Meadows Miller]

Gday

Yeah I get an awesome run out of tct both tct superbits from arsaw and std bronzed on tips onto solid saws I do prefer the Insertsaws and will be changing the new mill over to them in due course .

Ron run time in barked logs will be about  15 to 20000bft between sharpenings even though you could push them longer I do know blokes who are getting 40000bft a day out of their breaking down rig  and longer runs out of gangs and edgers it all depends on the workload each machine has and they sharpening in the evenings  or every other day ;)

a jockey or andrus  grinder will do tct bits you just have to get the diamond wheel for it

You will hear a distinct difference in noise pitch when running tct bits and saws vs steel plate (sprinsetts) or steel bits the tct has a cleaner noise and will hold its edge longer than steel plate or insert saws

There Is a reason bigger mills run tct saws even though it is a brittle compond it gives a longer run time when sharpened correctly I like to get a real keen edge for a start I have seen others who will push the saw hard for run time then do not take the time to get it back to a good keen edge which is like sawing with a blunt saw 

Carbide compositions have also come a bloody long way in the last 30 years also the arsaw superbit has supprised me many times after having some heavy metal/rock strikes

Stellite is another option and I did not mind running those saws and bits but like a chainsaw or chrome bits once you loose that coating your back to hss



Regards Chris

[Ron Wenrich]

Thanks for the input.

Right now, I'm not getting 20 Mbf out of a set of teeth, thanks to metal.  When the edger came in, it had carbide teeth on it.  Apparently, someone had some luck with it.

I've looked on the Arsaw site at their teeth, and it seems the way to go, if I want to go that way.  If I decide to do everything with carbide, the conversion is under $400, counting a diamond grinding wheel.  I know of a couple of millers that have converted to carbide, but they tend to be small mills. 

[bandmiller2]

Ron,the only way you will know is to try the carbide,Its a gamble with city trees,as you just have to accept your losses from tramp metal.A fancy metal detector will help but the fox will always find a way into the coop.Is their one guy there that will make a good millwright and filer.??Theirs no substitute for a good sawyer, some are one with the mill outhers just cut by wrote. Frank C.

[Ron Wenrich]

Sawfiling is a learned art form.  Some guys can do it, some can't.  It doesn't really matter what sort of equipment they have.  I'm dealing mainly with urban folks in urban wood.  I don't find them any different than the rural folks, as far as willingness to learn or their ability to do the work.  People are people.  Some good, some not so good.  They're just ignorant in processing wood, just like tons of rural folks. 

Right now I have a young guy I'm going to teach how to saw, and the finer points in saw filing.  He's been running the Mighty Mite, so he has a bunch of basics.  He doesn't have it in the filing department, as that was given to someone else.  His problem is running a saw that is too dull.  The filer isn't filing the saw quite right, either.  When he gets into the booth and is the primary man, then things will change.  He seems like a good fit, and has shown a willingness to learn.  He's bright enough to saw and good with the numbers. 

There is a pass through metal detector like those used in big mills.  I'm thinking that will catch most of the tramp metal.  I'm not willing to go the carbide route on the headsaw until I see what sort of track record I can get with the big detector.  They also have a big hand detector.  But, that ones only as good as the operator.

[Bert]

This is something i have experience with. We run either pipers from menominee or arsaw carbides. They dont run as smooth as plain teeth but we average 50 +mdf in dirty un debarked logs. Chipping is  not an is not an issue. Will saw 16d nails without skipping a beat. Feed rate does suffer somewhat,i believe due to a blunter edge even when sharp. We sharpenwith a jockey grinder and diamond wheel. $110 from arsaw.

[sawsmith]

The metal detector will pick up most of the metal in the log. However depending on the size of the log it will not detect metal that is deep within the log. And i'm thinking that most of your log's will be on the large size, since you said you were woking with Urban guys i'm thinking your gonna be sawing large Yard trees from within town limits. Most mill's with a circle head rig and band resaw do a scan with a hand held scanner before the debarker and then it passes thru a metal dectector after every board is cut off by the resaw. I did however notice you said they were running the teeth dull and carbide or not they gotta be kept sharp or the saws will be in repair shop more then they need to be since dull teeth + heat=Hammer job.

[Frickman]

I've run the standard steel bits and I've run carbide. I'll take carbide any day. We have a local company here that makes their own carbide bits out of used standall bits. Many of the area mills are running them. Now I run a small, part-time operation, at least on the milling side, and I run the mill, sharpen the saw, and do all the maintanance myself, so it's a little easier for me to keep on top of things. Sharpening carbide isn't that hard, in fact I've found it easier to sharpen carbide than steel bits. I would never, ever try to remove the bits to sharpen them. Number one, I hate the work involved. I'm running fifty bits right now and I try to break changing bits into two different sessions. Number two, I think that you could easily get the angle of the tooth wrong. I have found individual teeth will sit down further into the socket more than others due to minor differences in the teeth, shanks, and sockets. When you sharpen a tooth in the saw the grinder uses the shoulder of the saw as a reference point to determine the angle of the cutting face. If you removed all the bits to sharpen them you could conceivably have a bunch of different angles when you reinsert them. Maybe not enough to make a difference, but they would be different. Lastly, every time you remove a bit and shank you stand the chance of dropping one or the other or maybe even splitting the shank. Now if a shank splits maybe it was going to split anyway, but maybe it wasn't. I can't remember splitting a shank while the saw running, but I can remember splitting plenty of them while changing bits.

Last fall I had a couple of boxes of new steel bits leftover from the old days before carbide. I tried to sell them, I tried to give them away, nobody wanted them. I ran them myself this winter just to use them up and changed back to carbide a couple of weeks ago. It was a big change for the better to go back to carbide.

There is a little story I'll share about the shop that makes my bits. Simonds, the big dog in bits, saw they weren't selling many bits in my area. They sent a man out to find out why. Most of the mills he stopped at told him they bought their bits in town. He ended paying this saw shop a suprise, but still cordial, visit. The saw shop owner couldn't believe that he got Simonds attention.

Ron, there is one big difference in sawing performance between plain steel bits and carbide. When I run steel it seems they get progressively dull from the time they are sharpened. Carbide stays sharp until the cobalt binder breaks down and then they get dull right now. Someone may correct me on this, but I believe the acid in wood breaks down the binder in the carbide, causing it to dull. I don't have a debarker, and it seems that a little dirt doesn't affect carbide. Tannic acid in oak will.

[Bert]

I'm wondering if you ever tried the carbide Ron? I'm due for some new teeth and interested to know your opinion on them.

[Ron Wenrich]

Never tried the carbide.  I know one guy that did use them, and they were pleased.  They sawed trees off of Game Commission sales and kiln dried the wood and used it for flooring and they made custom doors and windows.  They didn't' have any problems.

The big drawback is if you're around metal and the initial expense of putting them in.  I never could get past the expense part.  Carbide is about 3 times as expensive just to install.  I would need to stretch the teeth out that far just to break even.  If I could make it up in better lumber or increased production, then its worthwhile. 

Seems to me that if you talked to your saw doc, they could tell you what others are running.  There's a reason most guys run a certain type of tooth.  The saw doc could fill you in.

[Mountain Guardian]

We tried carbide on the Mobile Dimensions mill my best friend has, he has no metal detector and nearly all of his logs come from peoples yards.  We noticed that the carbide teeth often shatter when you hit metal and are unable to be resharpened and used.  The hardened steel teeth though will often times be able to be resharpened.

If you are going to hit a lot of hardware in trees I advise the steel teeth, if you are not likely to be hitting stuff I advise carbide and getting a diamond sharpening setup.