To laser or not to laser that is the question

[DixieReb31]

How many of you long timers use a laser on your mill?  Are they worth getting?  

[Southside]

Go with a green one if you do. Red is useless in daylight.

[Gere Flewelling]

I have been experimenting with a green laser on my mill.  I hoped to set it up to mark the path of the band down the length of the log.  My mill is not under cover and unless it in dark or very cloudy out, it is very minimal at best .  When it is near sunset it will put a line on every thing for 50' around it.  I suspect it would work much better if you mill was under a shed roof.  At this point I am thinking of mounting it on the other side of my mill as it is on a magnetic mount.  I think it will illuminate my squaring arms if they are in the path of the band.  Might work good at keeping me from sawing into the squaring arms which are on the opposite side of the mill from where I am standing.  I purchased a green unit as everyone reported that green would work in the daylight as opposed to red.  I have a green sight on a pistol that works well in daylight.  The pistol sight is a focused dot.  The laser on my mill puts out a line which is naturally not as intense though very bright.  Either one would get you in trouble if you pointed them up in the air.

[Trackerbuddy]

Laser

[KenMac]

Check out Mule Mountain Sawmill on YouTube. He added green lasers to his Cook's AC 36. I have purchased the same lasers but have not yet installed them. I also intend to laser my scales for blade height.

[welderskelter]

OK, I have heard about these lasers but how much do they cost for a flat line one?

[tawilson]

I've bought a couple for $35 or so on Amazon. 

[doc henderson]

I use a green line laser, when overcast or at dusk, to see when I am past the log on the far end, and more to see when I am behind the log backing up.  It lets me go faster and not make as wide a margin on each end of the log.  and it is cool.

[DixieReb31]

Check out Mule Mountain Sawmill on YouTube. He added green lasers to his Cook's AC 36. I have purchased the same lasers but have not yet installed them. I also intend to laser my scales for blade height.

I did see that video, that's what inspired my question.  I just wanted to hear from other sources if it was really worth it. I think I will be getting a green laser very soon. Thanks 

[PAmizerman]

I have one on my mill and edger. My mill is under roof. If they quit I would definitely be replacing them ASAP.

[YellowHammer]

I'm a big fan of lasers. J have two on my edger, one on my straight line rip saw and none on the sawmill.  

Parallel sawing is done by eye or with the dragback fingers, and opening face is done by eye.  Using the uprights as a parallelism sight line is very intuitive.    

I'm not sure where a laser would mount on an LT70, I have a switch for one already plumbed in by WM.  

The Accuset sets height to within a 1/32" and I can generally eyeball to 1/8" without using it.

If there was a way to use it to center pith for quartersawing, I'd have one on the mill tomorrow. Is there?

[Ljohnsaw]

If there was a way to use it to center pith for quartersawing, I'd have one on the mill tomorrow. Is there?

So just thinking out loud...  Have a mirror set at not quite perpendicular to you at the far end - in such a way that your can see the end of the log but not yourself.  This mirror would need to be tall enough (2 feet?) that it wouldn't need to be moved but would cover the different diameters of log pith's.  Would only need to be 1 foot or so wide.  Mount the laser anywhere height wise on your head but near the blade makes sense to me.  It should be shooting from the same position that your are viewing.  It should be to the side of the log with a horizontal line that strikes the near end of the log, goes past the log to the mirror and reflects back on the far end.  You stand in a position that allows you to see the end of the log but not a reflection of the laser back at you.  Raise/lower the head until the laser is hitting the near end pith center.  Look in the mirror (with a spotter scope?) to see the line on the far end - raise/lower your roller bunk or whatever to get the pith where you need it.

To calibrate it, manually center the pith on both ends. The laser must be shooting parallel to the bed.  Set the laser height so it hits the pith on the near end, tilt the mirror until the pith on the far end it lit and lock the mirror in place.

[Walnut Beast]

If you can see the laser clearly it seems like it might work 

[tawilson]

Even if the laser doesn't light up the length of the log, eyeballing where the beam hits the near end with the blade gives a pretty idea where the cut is going to be. That's how I check clearance with the clamp.

[boonesyard]

I researched this for some time, and new I wanted to put one on the mill. I watched Mule Mountain and ordered the laser, switch and magnet he is using. 

The first issue I had after getting it was where to install. There just isn't a good place on my 50, ended up installing it near the dust chute just off the cover. When it gets low, it disappears behind the travel motor, no big deal, but there just aren't many options that work (at least on my mill).

The second issue is getting it adjusted, and this is a big one. I have messed with this thing a lot and it's almost impossible to get this thing right. Moving the mount up and down and getting the ball joints right, VERY difficult.

The third is once it's adjusted, you can't get the ball joints (mini RAM mount) tight enough to not move. The rare earth magnet is excellent, but the ball joints just can't stay tight enough. I used it for a day before it moved on me and I will say it worked very well when I did. I can see it pretty well in the mill shed during the day.

The laser is good. I plan on making a two piece mount with fine adjustments that will make it solid/easier to adjust.

[Southside]

FWIW this is the factory mount on my 70. 

 

[Walnut Beast]

FWIW this is the factory mount on my 70.  

Your cutting so fast and accurate you don't need one 😂

[PAmizerman]

I'm a big fan of lasers. J have two on my edger, one on my straight line rip saw and none on the sawmill.  

Parallel sawing is done by eye or with the dragback fingers, and opening face is done by eye.  Using the uprights as a parallelism sight line is very intuitive.    

I'm not sure where a laser would mount on an LT70, I have a switch for one already plumbed in by WM.  

The Accuset sets height to within a 1/32" and I can generally eyeball to 1/8" without using it.

If there was a way to use it to center pith for quartersawing, I'd have one on the mill tomorrow. Is there?

@YellowHammer
Laser upgrade to my sawmill ...set the pith in seconds. - YouTube

[Old Greenhorn]

Thanks for posting that video, it was perfect for what I am contemplating and answered a ton of questions. Does anybody know if the maker of that video is a member here? I should probably know that, but I don't, sorry. I would like to ask him where he got that laser.
 I have messed with a cheap one on the 50, but no permanent mounts. I will have to dig into this more, quite the timesaver for somebody like me.

[moodnacreek]

Mine all burned out, had one rebuilt and it burned out. If you are under a roof, pull a wire under a halogen lamp and get a shadow line. the trick is to put in a bulb ment for more voltage than you are using, that wayi t will last years.

[YellowHammer]

I like that idea.  Thanks for posting it.  Setting the pith is one of the most aggravating and time wasting things for quarterswing.

However - and I am not the laser police, but having worked with industrial and research grade lasers for over 30 years in my old job, up to and including Class 4, I am concerned that he upgraded to a 100 mw laser, which is a Class 3B laser, even though it is green.  Generally, these are not considered eyesafe, based on their wavelength and power, unless used in a non reflecting or diffuse reflecting environment, such as directing a beam off a non reflecting piece of wood or other material, or using PPE.  However, Class 3B lasers can be damaging (cataracts or "snow blindness" are a common side effect) if looked at in a situation of specular reflection (mirror), for any length of time, which is exactly what the operator would be doing when staring at a mirror to align the log end.  

Typically, class 3B operators would be wearing some sort of laser eyewear ($50 Amazon), which protects the operator eyes from direct reflection.

Typical warning labels for lasers are:
Class 3a: Do not stare into beam or with optical instruments.
Class 3b: Laser Radiation, avoid direct eye exposure.    

So personally, I would stick with a lower power, class 3a laser for this technique.

[luap]

I purchased a bosch laser intended for carpenters that gives two 40 foot lines at right angles to each other. green light with a universal mount for approx $100 .I will have to tape off the lens to block off the horizontal line for my application. Haven't used it yet, will have to wait for spring. This is on a circle mill inside a pole barn. so will mount it on the bottom of a truss looking down over the carriage in line with the saw. I have experimented with another carpenter laser but it didn't have a good mounting system Problem when try to use some thing not designed for application.

[Cruiser_79]

I like that idea.  Thanks for posting it.  Setting the pith is one of the most aggravating and time wasting things for quarterswing.

However - and I am not the laser police, but having worked with industrial and research grade lasers for over 30 years in my old job, up to and including Class 4, I am concerned that he upgraded to a 100 mw laser, which is a Class 3B laser, even though it is green.  Generally, these are not considered eyesafe, based on their wavelength and power, unless used in a non reflecting or diffuse reflecting environment, such as directing a beam off a non reflecting piece of wood or other material, or using PPE.  However, Class 3B lasers can be damaging (cataracts or "snow blindness" are a common side effect) if looked at in a situation of specular reflection (mirror), for any length of time, which is exactly what the operator would be doing when staring at a mirror to align the log end.  

Typically, class 3B operators would be wearing some sort of laser eyewear ($50 Amazon), which protects the operator eyes from direct reflection.

Typical warning labels for lasers are:
Class 3a: Do not stare into beam or with optical instruments.
Class 3b: Laser Radiation, avoid direct eye exposure.    

So personally, I would stick with a lower power, class 3a laser for this technique.

That is good advice. I'm looking for two lasers for my edger as well, and for the mill. But don't want people (children) or animals get hurt by the lasers.  For the edger the lasers are pointed to the infeed table so unless you are on your knees you won't see the lights. But if you raise the head of your sawmill the laser could be on eye hight, especially if the surrounding terrain is lower than the mill. What power should be 'safe' if you don't stare in the lights? And what power and wavelength would you need if you have a sawmill under a shed with TL lights and a bed length of 30 ft?
Prices are from lets say 20$ to 700$... If I check the Ali-like sites prices are in the 20-100$ range. The more professional suppliers start from 150 to 700$ for their laser modules. Are the cheap ones really that bad or are the expensive ones probably made in the exact same factories? Usually I don't like to buy cheap parts and stuff from china, but with these huge differences it start to make sense for me.

[tawilson]

I've got a couple hundred hours on 2 cheap Laserland lasers. I have one on the scale too. The last one took a month or so to get here.

[YellowHammer]

Laser exposure is complicated, and so that is why there are some high power laser pointers being sold.  It's also why the airline pilots and others get so wound up when they get flashed from the ground with an Ebay laser pointer.  

Most lower class 3R and just slightly higher are relatively safe for specific work.  For example, the laser on my SLR is a red 15mW, just into the class 3B range, but it is also ways pointed downward at a board, with no chance of direct eye exposure, only diffuse (non mirror) reflected exposure.  Also, visible lasers trigger a blink reflex, which is taken into account, and the severity of exposure is related to that, also.  If someone points a visible class 3 at you, you will reflexively blink and look away, and that blink will protect you.  Of course, as the lasers go up in power, they will cause damage before the blink reflex will protect.  In addition, some laser are invisible to the eye, so the blink reflex won't protect, and that is bad news.  So if a lower power class 3b is mounted to a sawmill, shooting down a log, away from the operator, if someone happens to walk by, looks into the laser and get flashed, they will reflexively blink and look away, and no harm.  

However, all this "blink protection" falls apart when the laser is pointed or is spectrally (full spectrum) reflected into the eye, and the blink reflex is purposefully overcome by the observer, such as when staring at a clear reflected beam for alignment purposes at a mirror on a sawmill, or with optical measuring devices (Class 3 laser transit or continuous emitting laser level), a higher power laser engraver with no shield on a reflective metal surface, or laser measuring equipment.  At that point, the laser will do damage because the observer isn't blinking or looking away, because they are intentionally staring into the beam, or a non diffuse reflection of the beam.

The other safety concern is the exposure distance, as with most things, and the further away, the less dangerous.  However, it's surprising how long these distances can be.  

Basically, it's a simple rule I was taught 35 years ago when I first started doing laser interferometry work, "Don't stare at the sun and don't stare at a laser.  Look away."

Or as my old buddy once told me "Hey Stupid, don't look into a laser, only pirates like to wear eyepatches."

So to answer your question, Class 2 are safe, and these comprise most of the consumer grade visible wavelength laser levels offered at Lowes or Home Depot.  All lasers are required by law to have their classification listed on the product label, so it's easy to check.  Basically, lasers of this class are only harmful for long duration direct exposure using optical magnification devices.

Low power class 3R are generally safe for non specular reflecting environments, but once you start getting into class 3B, you should evaluate the laser vs the intended use.  

Here is some easy reading on the subject:
Laser classification table - Laser Safety Facts