blade for slab flattening

[xlogger]

It's been awhile since I've been on here but I have lots of slabs to flatten on my mill where now is best place to get carbide tip 174"

[Brad_bb]

Can you do that?  With the way a slab can warp, unless you took a big enough cut so that the blade never exits the slab it might be possible, but you may still get some blade wander or undulation when you hit knots or changing grain direction.  I may make your blade go up or down.  I would not think you could count on a band doing such a wide cut to come out flat enough for finishing with a belt sander or Rotex.  I would never count on my mill for that.  That is why slab flatteners like Woodmizer's, or router sleds, or jointing of slabs which I can do to an extent with Woodmizer's MP100 mill planer.  If you use a band and keep it within the wood, it may end up taking too much wood, or you'd need an extra thick slab, which is then harder to dry properly before flattening.  I've never heard of anyone slab flattening with a mill band.  Another thing, guys have told me that carbide teeth will hold their edge longer, but will NOT be as sharp as you can sharpen a regular band to.  The regular band will dull faster but start out sharper I'm told.  So then the question is would a regular band be better and just use it for one slab? But then continue using that band cutting regular lumber to get your use out of it.  Or if you are sharpening yourself, just sharpen it and use it again.  For all my slabs I use a guy that I have kiln dry them and then flatten on his Slabmizer.  I've never sold any, so I just have a certain number flattened at a time and store the rest until I decide what to do.

[Ianab]

Yeah, the Slabmizer uses a big  carbide fly cutter. like the router bit from hell. There are other options if you can't justify a $X,000 machine. I've used a big router mounted on the sawmill frame. Slower because it's a 2" cutter with 3 hp, and all manual. But the principle is the same, anything the cutter can reach gets trimmed off, and you end up with a flat surface. 

[doc henderson]

I have flattened slabs with a twist, if you go slow, the blade will skim outside the wood on top and take down the curled-up edges with a cut.  Use what you got.  a belt sander would be some work but do the trick.  Or find friends with big slab flattening machines.  I use a regular steel blade.  I would not want to do it all day long.

[KenMac]

A portable powered planer will be quicker than a belt sander and works fairly well if operator is patient and detail oriented. I have used this as well as a router sled to flatten slabs. Both are messy, but the planer worked a little quicker to get close then finish with a light pass on the router sled. As was mentioned, use what you have in combination to get where you want to be.

[TimW]

Here is a question from way out in left field.....How about putting the slab on the ground and using a floor sander?  Can these be rented??

[Ianab]

Here is a question from way out in left field.....How about putting the slab on the ground and using a floor sander?  Can these be rented??

Problem with a floor sander is that it will tend follow any twist or bow in the board. Sand a banana, and you end up with a smooth banana, not a flat one. A sawmill / slabmizer / router sled gives the cutter a flat reference to work from. Any wonky parts sticking above the line get trimmed, while low parts aren't touched. 

Using hand tools like a power planer can work, but you will want straight edges / winding sticks and a good eye. Then you manually take down the offending high spots. A floor sander would work After you get the wood flat, to take out the assorted machine / tool / blade marks that any of those methods will leave. 

[doc henderson]

the old rotary ones are tough to use (learning curve) and can do as much damage as good.  There is a style called square buff that is like a big orbital sander.  I have been looking for one for years.  they are the type a hardware or big box store might rent and sell you the paper and or scotch brit material.  a beginner can easily use these, and they do a good job.  Many now install lux. vinyl instead of the 3/4-inch planks of actual oak.  The latter can last 100 years with refinishing's.

[Resonator]

I've thought about the floor sander idea too. Again I think it would need to be mounted in a frame to ride in, to keep it level and not follow the twist of the slab.

One of the You tube channels I watch is a guy with a circle sawmill operation that does woodworking as well. He shows how he made a simple slab flattening jig for his router, with electrical uni-strut channels for rails. He also uses a 1 1/2" bit in his router that is a facing bit for a CNC machine.
https://www.youtube.com/watch?v=-c8ztKmrWKM

[Larry]

Last carbide I got was from WM. The carbide tip is probably about 1/4 the size of TK. Might make a difference if you re-sharpen.

Brad is sorta right in allowing extra material so the blade doesn't come out and cut on one side only. If it does, I slow down to a snails crawl and let the blade chew. That is the advantage of the carbide, it will stay sharp when chewing where a steel band dulls quite fast and causes a wave.

I have a router bridge set up to flatten. It does an excellent job, might take an hour to set up and flatten one slab. With the sawmill running a carbide band I'm done in 5 minutes. Yes, I cut my slabs a little thicker when I plan to flatten on the sawmill. It's my time $$$$$'s versus material costs $$$$$'s. I'm expensive and material is cheaper.

[caveman]

WDH was the one to put me on to flattening slabs on the mill.  We did one for a repeat customer last week.  It was a wide cedar slab that was relatively flat but not perfect.  We put it on the mill and skim cut it, took it to the planer and turned out a really flat slab. 

Poor man has poor ways.  I'd love to have a 20" jointer, but the 3ph electricity is not in the cards right now. 

[xlogger]

Been doing it for a few years now with a 4 degree blade just thinking about getting carbine tip and seeing how it does. Yes Danny and I talked about this years ago. Been having good luck doing it this way.

[Hackeldam Wood Products]

WDH was the one to put me on to flattening slabs on the mill.  We did one for a repeat customer last week.  It was a wide cedar slab that was relatively flat but not perfect.  We put it on the mill and skim cut it, took it to the planer and turned out a really flat slab.

Poor man has poor ways.  I'd love to have a 20" jointer, but the 3ph electricity is not in the cards right now.

It is easy to use a 3ph converter. if you look up jackenglishmachines on instagram send him the motor tag and he will have the correct converter. I have been using one on my planer for a while, n.p.

[Hackeldam Wood Products]

I have  trued up many slabs on my LT 40. I also stack dried boards and edge them. I just use a sharp band and take it easy. 

[Resonator]

I've used a hand held planer and a big random orbital sander to flatten my slabs. Not perfect, but it works, and I can't afford a big helical head machine. Like caveman says, poor boy, poor ways. Mainly I just want to get them close, and have nice clean face to show wood grain, so it is more saleable to the customer.