Portable Mill Types -- Chain-Saw Versus Band-Saw

Pros and cons of the options for slabbing and milling. February 26, 2005

Question
Is there anyone making a portable mill with a chainsaw bar powered with a 4 cycle engine (not a chainsaw motor) instead of the bandwheel assembly?

Forum Responses
From contributor H:
I don't know of a sawmill built like that and can't say as I'd want one. For production work they are too slow and temperamental. They require a lot of maintenance, too. There are some slabbers on the market that use 4-stroke motors and I think they have chainsaw bars. Mobile Dimension comes to mind right off hand.



From contributor I:
Peterson sawmills make the sort of thing you are looking for, with engine options up to 27hp diesel or 24hp petrol. They are a lot slower than a conventional band or circle saw, but they will let you cut wide/long slabs out of large logs. Also highly portable, so you can take them to the large logs.


From the original questioner:
The Peterson looks like what I am looking for. We are not so concerned about production, as we are not in the sawmilling business. We just need something to slab wide walnut for our own manufacturing use. The Lucas slabber also looks pretty good and costs about the same as a manual bandmill and does not require the purchase of a $2000.00 band blade sharpener and setter. We already have the chain grinders to sharpen the chain on a Lucas. If anyone has had experience with the Lucas slabber we would appreciate any input. How much slower is a saw chain than a band mill, for example cutting a 36" x 8' walnut log?


From contributor K:

Lucas also makes a chainsaw mill cutting up to 60" wide. The speed of cut on an Alaskan mill with 9hp cutting head cutting 36" of white oak is... one foot every 5-10 minutes! Yes, it's horrible. I hear the 20+ hp units (Peterson and Lucas) will cut an 8' slab in under 10 minutes.


From contributor R:
I disagree with the statement that a chain mill will cut a 36" diameter white oak log 1 ft. every 10 min. The feed rate is more like 10 feet in 2-3 minutes on a 36" diameter oak log.


From contributor I:
It took just on 4 minutes to cut 36x96 beech with a chain mill, but that was with twin 075 power heads.


Gene Wengert, forum technical advisor:

Just because we have a mill or like to saw logs, it is okay to waste wood? That is, is it okay to waste our natural resources? Do we have any responsibility to society? If not, then how will we answer when the claim that the sawmill industry is destroying our forests?

Each 1/32" of kerf (or width of a sawblade) means that about 2% of the log will end up as sawdust. So a small band mill with a typical blade may make 5% sawdust. A chainsaw may make 16% or more of the log into sawdust. Or a chainsaw mill will have to cut 11% more trees to get the same amount of lumber. Of course, there are so many trees available (especially in Alaska), that why worry about being careful, about conserving for tomorrow, about giving the sawmill industry a good image?



From contributor R:
I did not point out in my post that I also use 2 Stihl 090 powerheads on my Sperber sawmill. It gives good power but definitely can't cut like a band mill.

In response to Gene's point on wood waste, I agree. That is why I only use my chain mill to bust up those logs my sawyer can't get a start on without the chain mill.



From contributor L:
Maybe we should just quit sawing altogether so there would be no waste. Better yet, if we are so worried about wasting trees, let's invent a way to prevent forest fires. The amount of trees that fire wastes every year makes the waste of a sawmill seem minute. Isn't there a use for the sawdust, anyway? Seems I heard something about some company making sawdust board and other companies making cabinets out of the sawdust board.


From Gene Wengert, forum technical advisor:
Indeed, sawdust can be used for particleboard or even MDF at times. But how many small mills market their sawdust? I have seen the majority let it fall on the ground.

Contributor R has indeed a very good approach.

Contributor L, maybe we should harvest some trees in a manner that would prevent forest fires from getting extremely out of control. Fire is nature's way of renewing the forest without producing any useful products for mankind. Fire losses are severe indeed.



From contributor I:
Twin 90's on a Sperber! Lustful man's toys.

Gene, the timber I cut with the chain mill is what would go as firewood or into a landfill
from back gardens or storm blown stuff that can't be shifted any other way.

I dispose of the millings by either burning them to heat the workshop or composting and donating them to the local allotments. The reason I use the chain mill and not my lt40 is that I have a market for wide slabs 2.5" thick.

My business has as small an environmental impact as its possible for me to make it and I take great pride in that fact, as do my customers.



From contributor R:
At the time, the 090's are what Sperber was selling on his mills. My mill is 20 years old this year, but still runs like new.

I, too, saw what otherwise becomes firewood or mulch. I have a tree service right in my backyard, literally, and over the 20 years I have known them, have benefited a great deal from some of the walnut, cherry and red and white oak logs they have taken down from residential lots. But today they actually prefer to turn these logs into firewood than to call me and get $100.00 for wood that typically has nails, clothesline hooks, etc. in it and no other mill would even consider. In defense of those who use a chain mill, they are a perfect solution for these kinds of logs and I do see that there is a lot more being gained than lost by using them.




From contributor F:
For a chainsaw mill built like a band mill, check with Linn Lumber. He has built this type mill in the past.


From contributor J:
There's a few differences between the Lucas slabber and the Peterson, namely RPM. The Peterson slabber is around twice that of the Lucas (more on par with a chainsaw, which is around 8000). A direct relationship to speed of cut.


The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).

Comment from contributor D:
The chainsaw mill takes approximately 1/4 inch kerf. That is not too far off from a circle mill. Its usefulnes in breaking down a log too large to fit a bandmill is where it earns its keep in my setup.



Comment from contributor T:
I have a prototype mill with two vertical chain bars and a common power unit. It can easily make two parallel cuts in 20" x 8' butternut in much less than a minute. It is designed to supply cants to a thin kerf resaw and also edge slabs as necessary. To rely on either a chain mill or a band mill as a complete production setup seems like mostly physical and mental abuse, from what I've seen. For the cost of a typical band saw mill, you can have a twin bar mill and a band resaw and both units do what they do best and, contrary to common thought, the kerf of the saw chain does not affect the cant - only the slab/side board. All the residue, including the sawdust, can be used as hog fuel or be allowed to return to the forest floor.


Comment from contributor C:
I find statements about the wastefulness of band mills next to chain saw mills because of the environment to be ridiculous. It is a fact that most trees felled by the wind inside city limits are summarily chipped into waste that fills landfills. A business like mine that grabs up old walnut trees or any type of hardwood and uses the wood is given favor by most city fathers, and they will actually pay you for the service of making lumber from their hardwood, so you can sell it, or put it into boat interiors, as I do.

Just because I use a smaller chain mill that can fit in the back of my pickup so I can tow a trailer to remove the wood when I am done does not make me wasteful. The city or county that chips the wood is wasteful, but no one rails against the chipping industry. No, chain saw mills have their place in wood conservation and it is far better to use a chainsaw to slab wood than to cut it into pieces for a fireplace. I have saved many old hardwood trees from burning in a fireplace by using an inexpensive chain mill so I can get there before the chippers arrive. It is unfortunate that some people can not see the effectiveness of a chain mill in conservation and the inexpensive use of it for expedience. So what if a very small percentage is turned into sawdust? It is much better than a whole tree being turned into chips.



Comment from contributor L:
A portable chainsaw will make more sawdust, but they are still not as harmful as the bigger stuff, which use heavy machinery, and the impact total of the forest is less with a portable mill. You can carry or take on a light vehicle and return home with the cut wood. I can take a big storm fallen tree home with my 6 hp vehicle, leave some sawdust, but no other harm.