Cheap Chinese Mills--How straight is the wood they saw after it is dried?

[esarratt]

Wood normally changes shape, it warps, while drying.

I am looking at the lower priced Chinese Mills and the lower priced America built mills.

I know I can dial in an EZ Boardwalk, Cooks or a Wood-Mizer to get a really straight 1/2" to 3/4" thick board for siding.

But, I was wondering.

1) How straight will a Chinese Mill saw?

2) And how much difference does this make after a board warps during drying?

3) Do boards used for siding on a house normally need to be planed before use?

4) How much does a large timber (3"x5", 8"x8", 12"x12") warp after being cut?

5)  Does the accuracy of a more expensive mill make sense given that wood normally warps during the process of drying?

Thank you for your thoughts and advice.

[btulloh]

The lumber off my low end hobby mill is no different or less accurate than a much more expensive fully hydraulic mill. The difference is in productivity and physical exertion. I can saw a piece of veneer on my mill that is 1/16" and consistent over the entire length and width. (Of course it will curl up like a potato chip when it dries.  Same as any mill.  Just the nature things.)

Crooked logs, leaners, side hill grown trees, off-center pith, etc. are going to produce problem lumber. An experienced sawyer can mitigate some of the problems with funky logs, but only to a limited degree.  An inexperienced or bad sawyer can make bad lumber out of a perfect log.

Good lumber comes from good logs, a good sawyer, good handling and drying, and good mill alignment.  Details are important in all aspects.

[APope]

Nice flat, straight wood that has dried is a function of the sawyer's and drier's skills more so than the sawmill it was cut upon. You can make airplane props and rocking chain pieces on a cheap mill or an expensive one. Country of origin really irrelevant...

[sawguy21]

The difference is in productivity and cost of repairs imo. If a machine is frequently down and parts or service information are not readily available it is not worth much. The bitterness of poor quality remains long after the sweetness of low price is forgotten is just as true today as when it was written 160 years ago.

[SawyerTed]

Log quality, species, sawing technique and drying technique determine how the lumber behaves.  

An LT 70 sawmill can ruin a lot of lumber faster than an HF sawmill in the control of an inexperienced sawyer. The opposite is also true, an inexpensive sawmill can make just as good lumber as an LT 70 in the hands of an experienced sawyer. 

Assuming that lumber "normally warps" is an erroneous assumption. So is assuming that cost of the mill means "better" lumber.  

Cost of a mill has more to do with features, quality, materials used, longevity, customer service and parts availability.

A friendly suggestion is to study on sawing technique and drying technique as well as drying characteristics of various species. 

I've sawn many timbers that are as straight as the day they were cut once they were dry.  A properly sawn and dried 8x8 won't "warp" twist or crook. 

[JimOfTheNorth]

... A properly sawn and dried 8x8 won't "warp" twist or crook.

@SawyerTed , can you elaborate on that please? As it turns out, I am planning on making some 8"x8" posts from Douglas Fir trees on my property. They will be about 18' long. My neighbour has a Woodland Mills bandsaw mill I can use but I was also going to try a jig that I can use my chainsaw on (that would be for the smaller trees that I would only get a single post from).  I had to fall a few trees a couple weeks ago (for other reasons) that are sitting on blocks off the ground waiting for me to get up the courage to do something with them. What do you mean by "properly sawn"? 

[Stephen1]

Welcome Jim, 18' is long post. More will drop in with their thoughts and expertise. I would want to center the pith on that 18' log. it will dry according the where the tree grew, type of tree and how well it is set to dry straight. Saw it and get it into the building mode will help the best. If your going to store the beam for a few years before use, I would overcut by 1/2" to 1".WhenI am ready to use it in few years I would square it up down to the size I want. 

[longtime lurker]

An LT 70 sawmill can ruin a lot of lumber faster than an HF sawmill in the control of an inexperienced sawyer. The opposite is also true, an inexpensive sawmill can make just as good lumber as an LT 70 in the hands of an experienced sawyer.

^^^ that's some of the truest words I've ever seen here. Good gear makes it easier, but that old adage about a good workman never blaming his tools is as true in this industry as any other.
Mind, log selection has a lot to do with it when you want 8x8"s to dry straight. I'm pretty handy at the silk pursues from sows ears tricks, but  cranky grain is cranky grain and sometimes it's just going to do what it likes, regardless of operator skill.

[moodnacreek]

The sawyer/filer makes the saw go straight even if it was a hand saw.

[SawyerTed]

... A properly sawn and dried 8x8 won't "warp" twist or crook.

@SawyerTed , can you elaborate on that please? As it turns out, I am planning on making some 8"x8" posts from Douglas Fir trees on my property. They will be about 18' long. My neighbour has a Woodland Mills bandsaw mill I can use but I was also going to try a jig that I can use my chainsaw on (that would be for the smaller trees that I would only get a single post from).  I had to fall a few trees a couple weeks ago (for other reasons) that are sitting on blocks off the ground waiting for me to get up the courage to do something with them. What do you mean by "properly sawn"?

Sure I can elaborate.  As mentioned an 18' 8x8 is going to be a BIG post.

Not every tree will make a good post.

Start with a good log with minimal knots
straight with little sweep 
large enough to "box the heart" or "center the pith" on both ends of the post (think bulls eye on the ends of the post) 

As has been shared, the movement of a post will be reflected by the characteristics of the log it is cut from.  The worst thing you can do on a post is try to get too many out of a log and include too much sap wood or split the pith.  The reason is sapwood dries at a different rate than heartwood or pith.  So if too much sapwood is left on the sides of a post, the post can crook during drying.  The best logs will be fairly symmetrical with the heart relatively centered.  If the heart is way off center in a log, you might consider looking for a different one. 

For an 8x8 the minimum small end diameter would be 14" or so.  You will cut one post out of the center of the log.  There will be side lumber that will come off as you saw down to the 8X8.  
The other alternative is if the log is large enough to cut posts that are free of heartwood and free of sapwood you could get several posts out of one log by boxing the heart wood in one post and cutting other posts that are completely free of heart and sapwood.  

To get five 8x8 posts from one log,  the log is going to need to be in the 34" diameter range on the small end, fairly straight and with few defects.  By centering the pith/boxing the heart in one post, there will be enough material left to cut four more posts.   Smaller than that it will be necessary to cut a single 8x8 post from the log and cut other lumber or smaller posts from the rest of the log.  

Drying posts also takes some consideration.  They need to be dried just like any other lumber with stickers and weight on top.  The stack needs to be in the shade.  Uneven drying of a properly cut post can cause it to move.  For instance, a stack of posts that receives late afternoon sun on one side is likely going to have some crooked posts.

[VB-Milling]

3) Do boards used for siding on a house normally need to be planed before use?

This is really a question of personal preference.  Are you looking for a rough sawn or planed finish for your siding.  There are many people here who think the finish straight off the mill is acceptable.  With the right blade, wood species, tension and feed rate, you'd be surprised at what type of surface you can achieve straight off the mill.

I just built two outdoor projects with lumber straight from the mill.

Have you looked into the lap siding attachments or would you want to straight saw the siding?  Lap siding "attachments" need not be more complicated than setting wedges under the cant to angle it.

[JimOfTheNorth]

Sure I can elaborate... 

That was very helpful, thanks so much!

[Joe Hillmann]

I am going to kind of go against the grain here and suggest that a cheap Chinese mill MAY  not be able to cut as good of lumber as a more expensive mill.  With a brand new blade nearly any mill can cut perfect lumber.  But as the blade dulls a tiny bit(but not dull enough to put on a new blade) having the mill perfectly adjusted can keep that blade cutting straight much longer.  If a cheap Chinese mill has really bad blade guides and no built in adjustment it will be harder to get good lumber out of it.  If it does have good guides and adjustment it should be able to cut good lumber.

Although the mill is only a small part of getting good lumber, the trees you select, how the logs are stored before being milled, and stacking and drying once milled can make otherwise perfect boards become garbage.

A cheap mill is going to be much more labor intensive to run than a top of the  line machine as well and it may not have the capacity for length or diameter either.

[SwampDonkey]

Personally, if I was to saw big diameter timbers I would stay away from pith and juvenile wood near it. I've seen a few 6" x 6" cherry split 4 ways toward the pith centre when air dried when sawed that way. That what you want? I'll show ya some. Not my sawing. :D Red pine does the same and they are used a lot up here for big posts, probably 20" or more between big whorl knots.

[YellowHammer]

Any mill can cut a crooked board.  Not every mill can cut a straight board, I've seen them, and it doesn't matter if it's Chinese or not.  I know of a local company that bought an LT70 and they couldn't cut a straight board with it if they tried.  It's not the mill's fault, it's the brother in law of the owner who says "They told me to saw wood, so I saw wood."

As people are saying, how it comes out after it's dried is not generally a function of the mill, it's the culmination of all the steps in sawing and finishing, plus the log itself and the experience and skill of the operator.  However, it's the sawmills job to be capable of sawing straight.  Some can, some can't.  

Just because it's a Chinese or any other country of origin mill doesn't mean it's not a good or bad mill, and the same with American made or home made custom fabricated.  Some are junk, some are jewels.

I have have owned the least expensive manual mill Woodmizer made, and I'm not sure it didn't cut the straightest lumber of any mill I've owned.  However, it was incredibly slow, labor intensive, and I sold it as fast as I could save up for a "better" one.  

The answer to the question, as far as I'm concerned, is like most things in life, you generally get what you pay for.  Same thing with parachutes and toilet paper.

[esarratt]

Thank you all for your comments.  That helps.

[Southside]

Same thing with parachutes and toilet paper.

Funny comparison - I have used one of them for the same thing.  I will let you figure out which one.  :D

[caveman]

cutting other posts that are completely free of heart and sapwood.  

Good advise has been given but how is one to cut posts that are free of both heartwood and sapwood?  Heartwood is the inner xylem, with the job of giving the tree strength and support and sapwood is the outer xylem or the portion of the wood that was alive and actively carrying water and nutrients up the tree on the day the tree became logs.

We cut quite a few 4x4's out of pine.  On small logs we get one per log and sometimes side lumber.  On larger logs, we box the heart in the center of one 4x4 and take the same number of 4x4's off of each side.  For example, take a perfect 19" small end diameter log.  Cut it into three cants with the pith centered in the middle cant.  Flip the cants and saw nine 4x4's out of the three cants, centering the pith in the middle 4x4 again while sawing to the bed.  

For the sake of this discussion, some of the longleaf pine we saw may have a 14" heart and only five inches of sapwood outside of the heart.  On the other hand, we may saw some faster growing slash pine that has a four inch heart and a foot of sapwood.  

[longtime lurker]

Regional semantics probably. Around here most call the pith heartwood,  heartwood gets called true wood, and sapwood is if course sapwood. 
Incredible to me is a boxed heart 4x4, here that would just blow apart under drying stresses. Strange old world huh?

 Big brand or cheap import, well made or cobbled together with cable ties and 8 gauge wire, part of being a good Sawyer is adjusting the saw until it cuts well. Never yet seen any mill that cut perfect straight out of the box no matter what factory it came from. You'll do better with good saws on a cheap mill than cheap saws on a good mill though...  Bandmills are basically unchanged for a hundred years but saw technology has come a long way 

[YellowHammer]

Same thing with parachutes and toilet paper.

Funny comparison - I have used one of them for the same thing.  I will let you figure out which one.  :D

You jumped out of an airplane with a backpack full of toilet paper?  You are a tough son of a gun!! :D :D

[esarratt]

I bought a Norwood LM29.  I have had good luck with Canadian products.  We shall see.

[hacknchop]

I'm a Canadian product come to think of it , enjoy your sawmill .