WM LT40 Max Board Width

[pnyberg]

Wood-Mizer claims that the LT40 will mill a log up to 21 feet long and 36 inches in diameter, and can produce boards up to 28 inches across.  And I put those specs on my website before I'd had the chance to push any of those limits.

I ran up against the log length limit in one of my first jobs, and while I found that the 21 foot claim is literally true, it would require positioning the log with a degree of precision that seems pretty impractical, so I bumped the claim on my website down to 20 feet to give me some slack.

I had my first 36" diameter log up on the mill this past weekend.  Of course the log did have some irregularities that required some chainsaw work to complete some of the initial cuts, but I'll allow that Wood-Mizer's claim that the LT40 can mill a log this size is basically true, if you're willing to work at it a while.

Once I had this log reduced to a cant, I started milling boards, and for the first time noticed that the widest board that I could mill from a square cant was about 24 inches, not 28. 

It's true that the distance between the blade guides is about 28 inches, so in theory a board that wide could be cut, but as a practical matter, I can't figure out how a person would actually do this.

So, I'm thinking that I need to edit my website to reduce my maximum board width claim to 24 inches.  Am I missing something?

I know how folks like pictures, so here's the end of the 36 inch log.  The owner believed that it was walnut, but it turned out to be pine:



The next log was almost as big, and was black walnut:



--Peter

[Magicman]

Peter, yes I would edit that 28" down to 24".  You can not saw a 28" cant without making a jig to offset it.

You will find that with those 36" logs, you may need to lower the side supports down a bit and allow the log to roll away from the log clamp and closer to the off side blade guide.  Just be advised that when doing this, don't make a mistake and lower them too much and allow that log to roll off.  Doing so is NOT a good thing.  When sawing 36 inchers, I always lower the side supports in order to make more cuts before turning.

Now back to the 28" wide board.  With the log rolled as described above, you can saw off slabs that when edged will be close to 28".  This can be done, but certainly not practical.

[sgschwend]

It is a good idea to have a few inches space to handle those odd shapes down the log.  Pushing the limits normally turns into a big headache and sometimes damages you machine.

As Magic points out you can drop your stops but you may have the log roll off the machine and wipe out anything that gets in its way.

I see you had a bad log the wood turned all black.

Steve

[Tom]

I found that life was a lot easier if I didn't advertise maximums.  I told people that my LT40 would cut a 20 foot log and a 20 inch board.  In fact, it would saw a 21 foot log and a 22+inch board.  I could make it saw more than that, but it was left up to the astoundment of the customer that I was able to perform miracles for him.

The LT40, in 1990 was sold as a 20 foot mill.   I guess the pressure of other saw mill manufacturers got to Woodmizer and they started pushing the size of what the mill would saw.

There is a reason that you purchase a mill that will cut 21 feet and that is so that you can cut 20 feet.  You will find that most of the lumber and construction stuff is 16 feet.  A 20 foot mill makes it a lot easier to hit the mark than penny pinching for a 16' mill.

You're better off if you don't brag too much and advertise how fast you are too.  That is true, especially if you decide to saw by the hour.  You will find yourself worn out the first night and unable to perform the next day, while the customer judges you as mediocre because you didn't own up to your promises.

There are many reasons to look at the logs first.  Granted, being able to saw them is a priority, but, being able to perform in a satisfactory manner is another.  If the site is not up to specs, it gives you a chance to make allowances and for the customer to understand.

[paul case]

yep you ought to respect those limits.
my mill cuts 16'6'' long and its a trick to get a log that long in the right spot . i have learned to cut them longer and trim the ends to fit once the log is on the mill. just another quick way to make more firewood!  pc

[Dave Shepard]

It requires a lot of planning, but it can be done. 22 seems to be the easiest width to hit. Big stuff I just split with the chainsaw now. If I want wide stuff from really big logs, I'll cut two adjacent sides with the chainsaw, now I've got something I can easily work with on the mill.

[logwalker]

With a big cant you can use the toe-boards and lift the cant and put spacers under it so it will slide over to the inboard guide. you then can cut the maximum width. The cants weigh enough that they stay put while you saw them. But cutting 28" with a LT40 is asking a lot. Use a very sharp blade with a little extra set. And hold your tongue just right.

Joe

[sparks]

The throat opening is 28" from guide to guide. From the cant stop blocks to the outer guide is about 25".

[pnyberg]

With a big cant you can use the toe-boards and lift the cant and put spacers under it so it will slide over to the inboard guide. you then can cut the maximum width. The cants weigh enough that they stay put while you saw them. But cutting 28" with a LT40 is asking a lot. Use a very sharp blade with a little extra set. And hold your tongue just right.

Joe

Ah.  I see how this could work in theory.  It's good to know how it could be done, but I think I'll save this for a time when I'm asked to perform a miracle, as Tom suggests.  I think 24" wide should be enough to satisfy most people.

Thanks,
    Peter

[Magicman]

Just also remember that if you have not had a log or cant to fall off of the "off" side y e t that it is no fun.

As I stated in a previous post, moving logs/cants to the left is sometimes necessary, but never without risk.  Always look and be double sure that you have the right hydraulic lever and that you are moving it in the direction that you intend.

How do I know this  ???

[backwoods sawyer]

Always look and be double sure that you have the right hydraulic lever and that you are moving it in the direction that you intend.

Was that on the big Myrtlewood log or the big Oak log that I done that. Hmmm I think it may have been on both of them. Or was it the fir log that the cat dropped on the back side if the stands on the mighty might. Depending on how the mill is set up as to how difficult it can be tor retrieve a log. Be glad that your mill is 21' mine will only cut 20' 1" setting the log on and then trimming it down to 20' makes positioning the log a bit easier. And when cutting those 24" wide boards don't forget to breath and don't bite your tongue. 

[Chuck White]

Just also remember that if you have not had a log or cant to fall off of the "off" side y e t that it is no fun.
How do I know this  ???

MM is right on with this one,  even a very small log, say... 8 inch is no easy thing for one man to move out from between the rail and the tire.
Also like MM, How do I know this?

With a big cant you can use the toe-boards and lift the cant and put spacers under it so it will slide over to the inboard guide. you then can cut the maximum width. The cants weigh enough that they stay put while you saw them. But cutting 28" with a LT40 is asking a lot. Use a very sharp blade with a little extra set. And hold your tongue just right.

Joe

I've done this one too!
Just raise up the cant and place an inch board or two under it and set the cant down onto the inch board, then use the clamp to slide the cant to the inside!
It works, but, be careful.
Chuck