Bi-Metal Blades for Sawing Wood with Nails

You should always try to de-nail the logs or timbers before sawing, but for the occasional nail, careful sawing with a bi-metal blade may prolong blade life. April 10, 2007

I own a Wood-Mizer LT40 Super from 1996 and I use Wood-Mizer's DoubleHard bands with as well as their resharp services. In general I am very happy with the machine and the bands they sell. I saw mostly hardwoods: white/red oak, hard maple, ash, walnut, etc.
I have a problem, though. With the WM I do a lot of sawing of urban logs and resawing of reclaimed timbers. Depending on the specific job I am on, sometimes I come across lots of foreign objects in the logs – nails, mostly. Usually it just dulls the band and I can get them resharpened, but it really slows me down and cuts my production. I own a metal detector that I can use to hunt for the nails, but this is slower than just changing the blades after I hit something.

Does anyone have ideas? I called WM about bimetal bands, but they don't sell or recommend any. I think Simonds and Lennox sell bimetal bands. Anyone have experience with these bands and hitting nails?

Forum Responses
(Sawing and Drying Forum)
From contributor R:
I have used Lennox bimetal blades to saw logs from old houses and tobacco barns here in Virginia. The old square nails did not give me much of a problem. With the more modern nails, I eased my way through the first cut on each side of the log to see what was under the surface and used plenty of lubrication. When touching the unseen nail at a very slow feed rate, it did not overload the teeth and cause them to break or dull very fast. I first bought two bimetal blades and experimented until we found the preferred feed rate and amount of lubrication. Most of my cutting of these logs was on a manual mill and you could really feel the nail when you first pushed the blade through a log. I just sold my manual mill and purchased a Timber King B-20. So with the hydraulic feed, I may have to reinvent my methods of sawing old reclaimed logs. The bimetal blades worked fine for me.

From contributor J:
We saw a lot of antique lumber, and I have used bimetal blades and Wood-Mizer blades. I think you will find that the Wood-Mizer blades cost half what bimetal blades do and I do not think a bimetal blade will last twice as long. As far as nails, bimetal blades will only cut a few and still dull. Also, once you cut the nail it is still in the wood, so how will it be machined? It will tear up blades and can be dangerous if left in boards. We scan and denail all our lumber before we cut it. You only scar the top of the beam, but if you pull the nails after you cut, then you mess up one face or both of every board with a nail. We have cut many loads of old lumber and still have found no miracle solution for nails, rather than just to dig them out.

From contributor R:

Just a follow up on my previous post which I should have explained better… I totally agree with contributor J. We do try to remove everything from the beams before cutting, as any good sawyer should. But we are still going to miss a few and this is the method we use to proceed from that point.

I also cut metal and designed cutting tools in manufacturing for thirty years and know a little about metallurgy. Ms. Connie Flanagan at U-Cut Enterprises can answer any question about any type of blade made.