Laptop Controlled Setworks

[Don P]

For indexing it can you just hit it with a spot of "paint" while spinning and scanning?
Are we morphing into more than the op intended?

[jpassardi]

Well all of those early experimenters had failures, Southside. We just hear the success story. The guy with the first dairy didn't repeat the story of when he milked the bull first, or had the chicken poop omelet. That's why everyone thinks success comes easy😂

Very true BB: it's rare that excellence is achieved without failure along the way. The key is learning from the failure, have an open mind and not give up.

[cxsmith]

I've been in the Automation business for 33 years. I've own my own integration business for 22 years.

1 - what 3d vision system are you looking at?

2 - how are you going to scan a log? How long is the log? Let say you want to scan a 15' log. Do you move the camera on a 15' slide?

3 - your going to have to rotate the log for the vision system...  You ll have to send measurements... (Unless you have a way to pass the log thru a 3d scanner and some software on the pc can do your calculations then send a motion profile to a plc or cnc controller, big bucks)

Then you have a huge problem with rotating the log. Ok we have and Encoder. But what if the log slips on the hydraulic rotating and it doesn't match the the Encoder postion to what the vision is seeing.

4 - rotating the log, the mill has hydraulics, you can do positioning with hydraulics but you ll need a specail controller. That's separate programming from the plc .

I've seen steppers motors mention, they are to small to move anything that needs alot of force. You'd have to go to servos. Servos are huge dollars and then you need axis controller cards for the plc. Those aren't cheap either.

Still have the issue of the log slipping and losing your postion. Bark breaking off, wet log, weird shape.

Just a quick mind dumb as I read this thread. I'm retired,  and own a woodmizer LT15 wide. Been milling for a year , sawing lumber for a house me and the Mrs are building.

You'd have 2 to 3 times the cost of a good hydraulic mill just for controls. I really don't think it would work.

Sorry if I'm a buzz kill.

Re buzz kill: Not at all. I have considered all of these broadly already, but you mentioned some details that I had not, which is good.

1. The idea is that I'm going to use laser triangulation myself. It's just matrix algebra plus distortion correction. I hadn't considered what a problem ambient light could be, but since the laser is monochromatic it would be easy to pre-filter by hue to increase the contrast. Edge detection would then go a long way.

2. I would plan to scan as long a log that fits on the mill bed. If they've got material handling then that would make lineal scanning with a single laser simple, otherwise I can use as many lasers they want slices over the saw mill bed.

3. Yes, if I can control the hydraulics then I can rotate the log. Of course, that's problem 4. Since the PC and PLC can talk then where the computation happens isn't that big a deal, the software can handle that. Slippage can be corrected for in software. I have not tested it yet, but I have a couple ideas for how to do that.

4. Can you tell me some more details about the separate controller for hydraulics? What about the system would preclude using the same PLC? Thanks.

[cxsmith]

Problem is that making an uneconomic job 5 or 10% more efficient probably doesn't make it economic. You can saw low value softwood construction lumber with any sawmill, but is it worth it? Probably is if it's your logs, and you need the lumber because you have cut out multiple middlemen.  But if you are buying logs, and trying to sell the lumber wholesale? Deduct your operating costs and maybe you are making $5 an hour, or less. Better to go and flip burgers, and save the overhead expenses and wear on the equipment.

But there are two things that make the system's value more than $0.50/hr:
1. To convert a given % decrease in expenses to % increase in profits, you'll have to divide by the profit margin. Since margins are low in milling, that works in automation's favor. By some back of the envelope calculations this could bump $5/hr up to $9/hr. Still not economical yet, but...
2. Automation means that while the mill is cutting your logs you can be doing other stuff, so there's much less labor cost. Right now I don't think Wood-Mizer makes hardware that can align flitches with edger blades, but if so then that would cut out the majority of labor for making green lumber. I don't have experience working in a sawmill, so these labor times are estimates based off of videos I've watched and other forum threads I've read.
Before

• Purchasing (~20 min / mbf)
• Storing and loading to log deck (~10 min / mbf)
• Milling to flitches (2 hr / mbf)
• Edging (1 hr / mbf)
• Stacking and selling (1.5 hr / mbf)

After

• Purchasing
• Storing and loading to log deck
• Milling
• Edging
• Stacking and selling

Going from 5 hr to 2 hr would move $9/hr to $22.50/hr, which seems to be within the realm of profitability.

[SawyerTed]

Woodmizer's  EA3000 Edger system is an optimized system.

https://youtu.be/HPDaRd7JfPg

The Forest Service has considerable research on optimizing smaller mills.  Here's one paper from 2011

https://www.nrs.fs.usda.gov/pubs/jrnl/2011/nrs_2011_lin_001.pdf

There's room for improvement but much has already been done.  Sizing up the competition is important.

Cooper is only one company with an end dogging mill carriage.  What how the logs are skewed to dog the centers of each end.  

https://www.coopermachine.com/Our-Products/123/Skewing-Overhead

McDonough, USNR, TS Manufacturing and others have systems.  

Send a cant from a twin saw like that to a curve sawing gang and all you need is an optimized edger.  

In less than a minute a log can be broken down and boards headed to the grade station, trim saw and sorter.  Each stage has to be optimized and automated. 

[SawyerTed]

Then there's HewSaw

https://youtu.be/7_Qcilfc8jk

[Southside]

Eh, what's $150 million amongst friends?  :D

[SawyerTed]

Bring your logs we will have a sawing party!   :D

Just pointing out that there's not much meat left on the bone with modern optimization. 

[longtime lurker]

As a small sawmiller...

Optimisation during log processing isn't really of interest to me personally ( although I see beyond myself to the production side of the business where it does apply). I've already got a scanning system that can not only scan the outside of a log and integrate with the log turner to present the best face but has the ability to deviate from the initial sawing pattern as sawing progresses based on progressive scanning and a quality feedback loop as the log is broken down.

I've got a processor that can assimilate all that information running on about 0.2% of it's capacity, if that. A large part of the processor capacity is either on standby, or engaged in fish/beer/boob analysis programs during sawing operations.

My eyes and my brain outrun my sawing equipment by a mile. I'm not exactly stressed thinking about what size to cut next or how to get best recovery because I am yet to see a machine that can match my ability. And I've got enough seat time that it all happens with minimal input beyond push the lever pull the lever.

And that's why I am sceptical about small mill optimisation: At the speed we process logs I got this. Now if I had something like an R250 Hewsaw that would change, and I would be the limiting factor on the machine and optimising systems would make sense. But I don't have that type of saw and if I did I wouldn't have enough log volume to keep it fed for more than a week each year.

Optimised edgers are however of interest to me.

 But the automation that will improve my business is more along the lines of replacing grunt labour behind the saws. It ain't sawing that limits production here -  it's stacking wood, sweeping floors, grease guns, sawdust bunkers, customer liaison, account management, and the admin burden eating into my week that limit sawing time. And the thing is I like sawing, I don't want to reduce my time on the saw to do more of the stuff I dislike.

I believe in the tech. I believe it's the future. But imma be a holdout when it comes to implementation until such time as it can do better quality - not just bigger volume - than me.

[cxsmith]

Woodmizer's  EA3000 Edger system is an optimized system.

https://youtu.be/HPDaRd7JfPg

The Forest Service has considerable research on optimizing smaller mills.  Here's one paper from 2011

https://www.nrs.fs.usda.gov/pubs/jrnl/2011/nrs_2011_lin_001.pdf

There's room for improvement but much has already been done.  Sizing up the competition is important...

1. That's fantastic. I notice that there are only two blades on that edger. But if you're cutting something that's slightly over 10" wide and a 2x10 isn't an option, then it'd be nice to have the capabilities to cut a 2x4 and a 2x6.

2. Actually, I can see that the paper already mentioned some possible improvements:

Accuracy of the log sawing simulation is limited because a circular cross-section model is used to represent real logs.

That would definitely leave a lot of wood on the table since they aren't optimizing for the actual shape, which I already do in 2D and can extend to 3D.

All flitches produced from logs were edged to remove wanes

That would be an easy fix to make the optimizer adaptable to wanes.

I also think that using an exhaustive search is feasible instead of dynamic programming. Computer speed has improved in the 12 years since that was published.

[Ianab]

1. That's fantastic. I notice that there are only two blades on that edger. But if you're cutting something that's slightly over 10" wide and a 2x10 isn't an option, then it'd be nice to have the capabilities to cut a 2x4 and a 2x6.

Generally if you can saw a 2x12 vs a 3 2x4s, it's worth more. Take the 2x4s from where you can't get anything bigger. The mill can always take a wide board and rip it down to a smaller dimension with a thin kerf re-saw if they more need material to fill an order. 

The HewSaw is a good demo of how optimisation works, Logs seem to be scanned twice in that system. Once on the way in, and the log then rotated for best results. And then again once two outside slabs have been trimmed off, possibly to judge grade of the logs (how many knots?) and make another decision there. But it's a 3d scan, as can be seen on the screen shots, hence the rotation to get the best solution with sweep and butt flare accounted for. 

As others point out, with a small sawmill us meat-sack brains have the processing power to look at a log and get a decent solution, even adjusting cutting patterns on the fly as we see the exposed cuts. With a HewSaw i'd get brain fade after a couple of minutes and production would suffer. But it does show the level of optimisation that's possible with current tech. 

Adapting that to a smaller operation is the issue. How much would it cost, and how much benefit would it bring? Asking those questions isn't silly. 

I am also reminded of the tale of a highly automated factory. It could be operated by one man and a dog. The man was just there to keep an eye on things, and the dog was trained to bite him if he messed with any of the controls. :D

[beenthere]

1. That's fantastic. I notice that there are only two blades on that edger. But if you're cutting something that's slightly over 10" wide and a 2x10 isn't an option, then it'd be nice to have the capabilities to cut a 2x4 and a 2x6.

Also, in addition to Ianab post, mills have the return lines to follow up on additional recovery after the 2-saw operation. 
Breakdown of a log into cants of flitches, then further processing taking the best available and then making a new decision for the next "best available". Some refer to it as a merry-go-round. 

[SawyerTed]

Woodmizer's  EA3000 Edger system is an optimized system.

https://youtu.be/HPDaRd7JfPg

The Forest Service has considerable research on optimizing smaller mills.  Here's one paper from 2011

https://www.nrs.fs.usda.gov/pubs/jrnl/2011/nrs_2011_lin_001.pdf

There's room for improvement but much has already been done.  Sizing up the competition is important...

1. That's fantastic. I notice that there are only two blades on that edger. But if you're cutting something that's slightly over 10" wide and a 2x10 isn't an option, then it'd be nice to have the capabilities to cut a 2x4 and a 2x6.

All it takes is money...

[Southside]

And a bottle of antacid when one thing gets out of time with those systems......Mayhem incoming...

Case in point 
https://www.youtube.com/watch?v=YZ3FwsZoedI

[SawyerTed]

Yep!  When big machines go bad, they go bad BIG!   :D :D

[cxsmith]

...Adapting that to a smaller operation is the issue. How much would it cost, and how much benefit would it bring? Asking those questions isn't silly...

All it takes is money...

In response to both of you I think it could be done far more cheaply that many think. The customer supplies their own mill. In return, you need a scanner, a PLC, switching electronics (eg power transistors for PLC signal to stepper motors), a PC, and a hydraulics control card. My goal is to implement a scanner with off-the-shelf hardware. PLCs cost, what, $200 for a decent one? Switching electronics could be assembled off the shelf. The PC I'm already renting on the cloud. So that just leaves the hydraulics control. Those don't look cheap, but it definitely wouldn't be a multi-million dollar buildout. Or even more than ten thousand. I think that could put it easily within reach of a small mill.

[beenthere]

cxsmith
Go for it. We'll cheer you on. Help along the way if we can, and I sincerely hope you succeed.  

What is your next move? Any wrinkles needing ironed out?

[cxsmith]

cxsmith
Go for it. We'll cheer you on. Help along the way if we can, and I sincerely hope you succeed.  

What is your next move? Any wrinkles needing ironed out?

Thanks! My next move is from Alabama to California. Unfortunately my car is already gone or I'd offer Yellowhammer a very nice lunch to pick his brain. I've got more confidence in my product's fit now, and when it's more developed I'd be happy to make good offers to early adopters.

[beenthere]

My next move is from Alabama to California.

:D :D
Not what I meant by "next move", but you did take me literally and is what I asked.  8)

[cxsmith]

...Not what I meant by "next move", but you did take me literally and is what I asked.  8)

Right, sorry that was a way too oblique way for me to say I was putting it on hold while I get settled in to my new home. But now that I'm done moving I think I'll investigate which make of mills would be easiest to attach a controller to. Again, thanks everyone for the information, I think things are a lot clearer for me now.