Commercial mill questions

ncmill · January 20, 2016, 09:44:26 PM

New to the forum and to sawmilling. Sounds like quiet a few are going to think I'm crazy but I recently bought a production mill, we currently mill about 4mind a year. I am looking for ways to work towards being a more automated mill as I improve the mill over the next few years. Anyone have any experience with automating their commercial mill to reduce labor and increase efficiency and where is the best place to start to achieve this?

Magicman · January 20, 2016, 09:58:40 PM

I have no idea, but Welcome to the Forestry Forum, ncmill.

Adding your location and also your sawmill brand/type to your profile helps with questions.

Alligator · January 20, 2016, 11:28:47 PM

Welcome to the Forestry Forum
I ran a dirt floor commercial mill for 20 years, 20 years ago. Where to start is inventory what you have? Everyone here has experience that can be useful. I'm sure you don't want to throw every thing out and start over. The best starting point is to streamline materials flow. Our mill had roughly the same production as you, maybe a bit higher in the early years, a bit lower in the latter years as more time was dedicated to breakdowns and repairs.

Take some pictures show us your current layout there are several that worked in really big mills. The less number of times hands touch a piece of lumber the less it cost to produce. Automation! There is really a lot of knowledge on this forum if you giveus/them a little bit of info to work with. This is a layout of CBLC Sawmill there was a Planer and automated stacker with the facility.

Sorry the image is not clear enough to read the legends. If you are interested I will post a PDF tomorrow. You can still see the flow.

sandsawmill14 · January 20, 2016, 11:45:20 PM

without knowing type of mill and setup its hard to guess but green chain, the way edger and chipper are fed are some big ones you dont want to touch anything you dont have to and nothing twice

ncmill · January 21, 2016, 07:22:02 AM

Thanks for the feedback. Correct, I don't want to throw everything out and start from scratch but just work on it over time (2-5 years). I will work on getting some pictures to post to help you guys out.

ncmill · January 26, 2016, 09:52:43 PM

Attached is a layout from the Brewco (mill uses Brewco resaw) website but it is the exact layout of my mill. Still working on getting you guys some actual pictures of the mill. Just to give a little more information we are a hardwood grade mill and cut approximately 4-5MMBF per year. Again, im new to all this and still have a lot to learn. Im interested in getting some help on becoming more automated and where to start? and where I can get the most bang for my buck? Again, im not looking to tear everything out but to make changes over time.

Ive been doing more research on automating the grading and green chain line, but is there anyone on here that can provide more information (or a good resource to go to) on the whole setup and lumber flow? from trimming, to sorting bins, to unscramblers, grade sorting, to stacking?

Thanks for the help

4x4American · January 26, 2016, 10:17:27 PM

:P

Alligator · January 27, 2016, 12:22:41 AM

I see 4 in the saw mill, assume 1 or 2 on the green chain? (debarker? 1) forklift operator 1? 5 or 6 about right? It looks like a efficient layout. Edger is self-tailing? The main thing is do you have snafus? Cants not following their proper path in the run around, having the operator stop to straighten, slabs an strips misbehaving causing operator to stop and redirect, logs needing manual attention from the log deck to the carriage.

Unscramblers / Stackers are fairly readily available on the used machinery sites. Standardize your drying packs to match your forklift fork length. Unscramblers / Stackers should follow that same width. They also have sticker notches so your stickers are alighned vertically. Sorters are out of my experience level. (sorter = 2 guys on the green chain :D) When we sawed hardwood it was sorted by species and length, but not width. a sorter that would do that would be pricey I think.

Get a go pro and film a 4 hour hour shift count the time you lose when there is no log hitting the saw. Is your head rig behind or waiting to drop a cant. In other words could your head rig produce enough cants for another secondary breakdown saw?

Sorry for running on

dgdrls · January 27, 2016, 05:42:06 AM

Welcome ncmill

I do not have commercial experience
but I'm certain the members here will
have lots of great suggestions and
experience to share.

Dan

longtime lurker · January 27, 2016, 06:31:55 AM

I agree with Al... Look at the flow of the mill, then look and look again. The resaw should never rest, cants need to be butted up against each other in the saw. Resaw starving = improve primary breakdown equipment. Resaw infeed sagging under the weight of the backed up cants while the breakdown guy has a nap = add more resaw. Sometimes the headrig guy might be able to take one more pass = less work for the edger.

Look to your filing room. Sharp saws cut faster and truer, and it's surprising how many mills cut below optimum because the filing room didn't get upgraded when the equipment did. Time cants through the resaw at various points in a shift. Put the biggest ampmeter gauge you can find in the resaw box... As soon as she's pulling more amps change out blades.

Replace edgerman with optimized infeed, that's a no brainer.

Every week there's a mill closing down somewhere... I
Unscramblers and auto stackers are pretty easy to come by.

GeneWengert-WoodDoc · January 27, 2016, 08:46:14 AM

It is usually essential in a well run and profitable commercial mill that the piece of equipment that is the most expensive (the head saw) controls production. (Some people say that the head saw is the bottleneck.) So, if you improve the headrig so it can out-produce the edger (the headrig has to go idle sometimes due to the backlog at the edger), then the money spent to improve the headrig is probably not well spent. So, any improvements have to look at the entire system.

So, let's begin by looking at the headrig. What can you do to increase production of quality lumber in the entire mill? Note that we want to crease quality lumber and that we want to look at the effect on the entire mill.

Do you have linear positioners on the head saw? They have GREAT benefits. Do you have lasers to indicate saw positions? Do you have computerized set works? Have you looked at the headrig for the value it produces rather than the quantity? Do you have a resaw? Do you have an edger?

Another key is contained in the statement "You can saw all day, but you only make money and profit when the lumber is sold." One thing this means is that you need to be sawing lumber that a customer wants and that the lumber should be as valuable as possible. So, what are the quality factors for your customers? Do you need to work on marketing too?

The sawing pattern...size of the opening faces, when logs are turned, which face is sawn next, and lumber thickness...are big factors in profit. Educating the sawyer and providing good indicators are very helpful. Note that there are retrofits that can be added to a carriage. Again, studies have shown the potential benefit of this can be 20% more value.

Finally, ask the sawyer and other employees what would help them to better and work faster and more safely.

As an edger saw gets the highest grade lumber for edging, and as studies have shown that the edger typically gets about 75% of the potential value in the unedged flitch, adding lasers and digital indicators, and maybe employee training in grading rules, can greatly impact profits. Edger training needs to be continual.

There are many more items. Your questions and comments might help us go further, but an on-site visit while the mill is running is certainly the best.

Alligator · January 27, 2016, 01:47:17 PM

Funny point of information: I checked lumber behind the mill at least 4 half days a month, (4 hours) the best production was on the cool/cold days between 40° and 50° days. Just cold enough to need a jacket not cold enough to need a fire/heater. The moral of the story is employees produce more when it's more comfortable to work than to not. The best 4 hr I ever checked was 12k. The only problem with that number was, I also oversaw all repairs and production problems, so lumber didn't get checked when there was a snafu in production somewhere.

Ron Wenrich · January 27, 2016, 04:27:14 PM

My best production was in October and May. Not only is the cool weather good on the men, but the machines work better. too. I also got better production on cloudy days.

longtime lurker · January 28, 2016, 06:08:39 AM

Summere here now, and production is down due to weather. I've shut down between 11.30 and 3.00 four days in the last week... It's in the low 90's which is bearable until you factor in 87% RH... In weather like that dehydration is a real risk because you sweat it out faster then you can drink water just standing around in the shed, much less working. If. Didn't think I'd have problems with the neighbours we'd be turning on the lights and running nights

ncmill · January 28, 2016, 07:46:59 PM

Quote from: GeneWengert-WoodDoc on January 27, 2016, 08:46:14 AM
It is usually essential in a well run and profitable commercial mill that the piece of equipment that is the most expensive (the head saw) controls production. (Some people say that the head saw is the bottleneck.) So, if you improve the headrig so it can out-produce the edger (the headrig has to go idle sometimes due to the backlog at the edger), then the money spent to improve the headrig is probably not well spent. So, any improvements have to look at the entire system.

So, let's begin by looking at the headrig. What can you do to increase production of quality lumber in the entire mill? Note that we want to crease quality lumber and that we want to look at the effect on the entire mill.

Do you have linear positioners on the head saw? They have GREAT benefits. Do you have lasers to indicate saw positions? Do you have computerized set works? Have you looked at the headrig for the value it produces rather than the quantity? Do you have a resaw? Do you have an edger?

Another key is contained in the statement "You can saw all day, but you only make money and profit when the lumber is sold." One thing this means is that you need to be sawing lumber that a customer wants and that the lumber should be as valuable as possible. So, what are the quality factors for your customers? Do you need to work on marketing too?

The sawing pattern...size of the opening faces, when logs are turned, which face is sawn next, and lumber thickness...are big factors in profit. Educating the sawyer and providing good indicators are very helpful. Note that there are retrofits that can be added to a carriage. Again, studies have shown the potential benefit of this can be 20% more value.

Finally, ask the sawyer and other employees what would help them to better and work faster and more safely.

As an edger saw gets the highest grade lumber for edging, and as studies have shown that the edger typically gets about 75% of the potential value in the unedged flitch, adding lasers and digital indicators, and maybe employee training in grading rules, can greatly impact profits. Edger training needs to be continual.

There are many more items. Your questions and comments might help us go further, but an on-site visit while the mill is running is certainly the best.

Thanks for all the input everyone.

Gene,

What are some of the carriage retrofits you are referring to?

Ron Wenrich · January 29, 2016, 06:17:04 AM

When we put in a new mill, we had to go through some re-engineering to get more production. One was to make alterations to the hydraulics. The headblocks were controlled by hydraulics. The reverse was fine, but the forward was slow. That was done by the mfg so the setworks didn't overshoot the mark. We put in a foot pedal that when you stepped on it, it gave the same feed as the reverse. Helped immensely with turning logs.

We also put in a computerized setworks. If you don't have them, you'll end up with sawyer fatigue a lot quicker. It also improves output through consistency in your cuts and your blocking. I think I got about a 5% improvement in production.

We also went to joysticks with all the controls on the handle. The forward and reverse on the headblocks was done with a trigger. I had a button for each taper, dogs up/down, etc. I was starting to get carpal tunnel when I was using the standard toggles and the like. It took care of all that.

A good set of downturns will decrease your turning time.

One thing you can do is make a time and motion study. If you want to look at the overall operation, you take a breakdown center and put down what it is doing. You do it for every minute, if you're doing multiple centers. Then, you simply put down what the machine is doing - making lumber, waiting for logs, waiting for boards to clear, etc. You can make anything you like, but it gives you a great idea where the downtime is coming from. Find those problem areas, then eliminate them. Sometimes it comes from the product you're making, sometimes from the log supply, sometimes from the help, and sometimes from the equipment.

You can also do a time and motion on the breakdown center. Instead of every minute, you would probably want to do it every 10-15 seconds. For a headrig, I would put loading logs, turning logs, setting, feeding log, gigging back, unloading carriage, waiting. You'll end up with an idea of how much time you spend doing certain operations. You want the feeding to be the one that uses most of the time. My sawing rate was 6-8 lines/min, depending on species and length. On an 8' log, my feed rate was about 3-4 seconds per cut. As you can see, the rest of the time was used to do other operations. You need to gig back, so you want as fast of speed as you can control. You need to set, which can only be done when you clear the saw. You need to turn the logs and set tapers. You can't feed any faster or you'll end up with miscuts. Figure out how to speed up those other operations.

Another thing we did was eliminate logs that took too long to saw for the output. We didn't have a top end for size, but the big ones don't always pay as the handling is so much more. We got rid of the small ones and put them into firewood. Although there is volume in them, there isn't enough to warrant putting them through the mill. My worst production was always in sawing locust posts. It took the same amount of time as sawing a tie log. Sometimes you need to figure out your optimum sized log and then figure out which ones you're losing time and money on.

Alligator · January 29, 2016, 08:03:01 AM

What Ron said is similar to what we did. The best one I've heard was in the IT field.

I had a friend that was an engineer at a Sony Magnetic tape manufacturing plant. Every two years this Japanese guy would come in and sit in a chair with a stop watch and a clip board, behind each engineer for 4 hours. After 2 or 3 times he got courage to ask why he came and just and sat and made notes. He was told that they were studying how long it took for these large engineering drawings to load on the PCs and when it would be beneficial to replace the PCs. The engineers made 70k a year and tiny pieces of time added up to large savings over a year.

That's where your money is.