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What do you want out of a mill?

Started by Wufnu, October 14, 2013, 02:18:58 PM

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Wufnu

Hi,

I'm new to saw mills and am looking to build a bandsaw saw mill within the next year or two.  My background is in mechanical engineering (metalwork, fabrication, repair, etc of jet components, mostly) and, after studying the mechanics, I feel these machines are not beyond the ability of most people to understand and their construction is using methods that have been around for over 100 years.  There is nothing magical about their construction.  I also feel most of the machines out there these days are far too expensive for what you get. 

Frankly, I think I can build a better mouse trap.  stupid_smiley 

The idea I'm germinating is making an inexpensive but modular mill.  As I begin to poke this rabbit hole with a stick, just to see how far it goes, it's immediately apparent that I should consult those that know more than I ever will.  That would be you guys. 

To setup the viewpoint correctly, imagine this: your best ol' friend in the whole world wanted to get a sawmill that was versatile, inexpensive, and durable.  He doesn't fully understand the complexities of milling (thus he isn't sure which features he needs) and is looking to you to help him pick out a mill.  You know he isn't going to get an industrial mill but you don't want him to get junk, either, or a mill that isn't going to be able to handle anything useful.  What features would you look for? 

That is:

What features would you consider must have?


What features would you consider desirable?


What dimensions (max log diameter, bed length, etc) would you figure encompasses 90% of logs most people will encounter?


Basically, I need to be pointed in the right direction on things to research.  I need to know what's important to you, the miller.  I'd like to evaluate all of the dynamics involved in milling, separate the variables, and boil down their functions and how to make them most efficient.  Then, find a way to tie them all in to a modular system that isn't garbage and won't break the bank.  Designed, manufactured, and assembled right here in 'Murica!  Probably at very limited quantities ;)

I realize this may be a bit much but I think I can do it.  Chance favors the prepared mind but fortune also favors the bold.  I don't think those characteristics are mutually exclusive. 

Sorry if this post is too long.  I'd have written a shorter one but I didn't have enough time during lunch break. 

AnthonyW

As I have looked at and for mills for years, I had given up due to money limitations versus the condition and asking price. Recently I managed to find one that I thought had the right price and just the right options.

If I was to build one and had the skills and access to autocad or solidworks as you may, ad was going to build a mill. I would mostly build a unit similar to the Woodmizer LT25/28. I would but leave room in the design to upgrade with minimal to no refabrication of parts. For example, the LT25 I just got everything is hand crank drive. There are no hydraulics. If I was to build the unit from scratch, I would allow for the system to be easily retrofitted/upgradable to hydraulic. This was I can see what options I would like to have or need to be hydraulic and which are fine as a hand-crank drive. Save some money now, and prepare to spend some later.
'97 Wood-Mizer LT25 All Manual with 15HP Kohler

grweldon

Quote from: Wufnu on October 14, 2013, 02:18:58 PM

I'm new to saw mills and am looking to build a bandsaw saw mill within the next year or two.  My background is in mechanical engineering (metalwork, fabrication, repair, etc of jet components, mostly)

My background is very similar to yours.  I do think that it is possible to build one cheaper and better than the commercially available designs given one has the proper place to do so and the proper tools.  I opted to buy one because at the time I had neither.

You will likely get in to a Ford vs. Chevy debate with your questions... AnthonyW already suggested the single vertical post design.  I would recommend something more along the line of a four-post design.  It's simpler and less engineering is required for a given amount of stiffness.  When you actually get to the point where you use one, you'll thank yourself for going hydraulic right from the beginning, no matter how much it looks like overkill.  Unless you are stationary and have a tractor with a front-end loader, you'll appreciate the fact that you can load a log in seconds with a hydraulic loader versus minutes with a cable winch using the parbuckling method, which is what I use.

Like you say, there's no magic to the designs until you get in to the automatic setworks.  From what I have observed, this adds quite a bit of complexity to the mechanics, but not really to the mechanical design.

Good luck, I'll be watching your thread progress...
My three favorite documents: The Holy Bible, The Declaration of Independence and The Constitution of the United States.

Jim_Rogers

Hydraulics for loading logs, as mentioned are high on the list, unless you have equipment to use to load the logs.
The next thing that I see that you need hydraulics for is to roll the log over.

I had a guy who I used to saw for, go out and buy his own mill, instead of hiring me to saw for him.
He figured he could do it cheaper.
Well, he bought a fully manual mill, I think it was a WM LT40 but no hydraulics.

He used to hire other workers to do the sawing and paid them by the bdft of lumber produced. Then he would go to the local tree services and buy the big butt logs that they didn't want to try and split for firewood, as they were so big.
He'd then have his guys saw these into lumber for flooring.
Well, after they squared them up they couldn't roll them over with a peavy and it took forever to roll them over with the system that came with a non-hydraulic mill. There is some type of gear-works you turn with a crank handle that lifts the log turner up and rolls the log over. These workers couldn't do it or didn't want to do it. And they couldn't make any money working like this. And most of the ones he hired, quit.

You have to consider how heavy a 24x24"x 8' or 10' or 12' log is when you are designing something to roll it over.

Most all of the sawmills I have ever seen, have it so that the cut face is rolled over against an upright. And then you cut the second face. This is cutting into a bark face again.
If you could arrange it so that the log rolled so that you were cutting into a cut face then there would be less damage to the blade by cutting into dirt in/on the bark of the tree.

I seem to recall that there was only one mill that was shown at a logging and sawmill equipment trade show that rolled logs this way. And I don't remember the brand name.

I'm sure if I'm wrong about there being only one, that others will post about the ones that do roll logs that way.

Jim Rogers
Whatever you do, have fun doing it!
Woodmizer 1994 LT30HDG24 with 6' Bed Extension

AnthonyW

Quote from: grweldon on October 14, 2013, 03:52:24 PM
Quote from: Wufnu on October 14, 2013, 02:18:58 PM

I'm new to saw mills and am looking to build a bandsaw saw mill within the next year or two.  My background is in mechanical engineering (metalwork, fabrication, repair, etc of jet components, mostly)

My background is very similar to yours.  I do think that it is possible to build one cheaper and better than the commercially available designs given one has the proper place to do so and the proper tools.  I opted to buy one because at the time I had neither.

You will likely get in to a Ford vs. Chevy debate with your questions... AnthonyW already suggested the single vertical post design.  I would recommend something more along the line of a four-post design.  It's simpler and less engineering is required for a given amount of stiffness.  When you actually get to the point where you use one, you'll thank yourself for going hydraulic right from the beginning, no matter how much it looks like overkill.  Unless you are stationary and have a tractor with a front-end loader, you'll appreciate the fact that you can load a log in seconds with a hydraulic loader versus minutes with a cable winch using the parbuckling method, which is what I use.

Like you say, there's no magic to the designs until you get in to the automatic setworks.  From what I have observed, this adds quite a bit of complexity to the mechanics, but not really to the mechanical design.

Good luck, I'll be watching your thread progress...

I had not thought of the 2-post versus 4-post aspect. I was thinking of options, overall size, and functionality. I, too, would have to agree that building a 4-post would probably be easier than a 2-post design. Especially for a first time at-home build.
'97 Wood-Mizer LT25 All Manual with 15HP Kohler

AnthonyW

Quote from: Jim_Rogers on October 14, 2013, 04:12:49 PM
Most all of the sawmills I have ever seen, have it so that the cut face is rolled over against an upright. And then you cut the second face. This is cutting into a bark face again.
If you could arrange it so that the log rolled so that you were cutting into a cut face then there would be less damage to the blade by cutting into dirt in/on the bark of the tree.

I seem to recall that there was only one mill that was shown at a logging and sawmill equipment trade show that rolled logs this way. And I don't remember the brand name.

I'm sure if I'm wrong about there being only one, that others will post about the ones that do roll logs that way.

Jim Rogers

I was wondering why that was and how I could get around it. Just thinking about it quickly and using the LT25 as an example. The blade saws from driver side hitch end of the trailer to the passenger side rear of the trailer. Would in be that hard to saw from the passenger side rear of the trail to the driver side hitch end. That would allow the log to roll the same way but only cut through the bark once. The drawback would be that the sawdutst would all end up on the log load side of the mill (again using the LT25 as an example).
'97 Wood-Mizer LT25 All Manual with 15HP Kohler

Ga Mtn Man

On medium and large diameter logs, you will waste a lot of lumber and your slabs (waste) will be very heavy if you try to square up the log in one pass per face.
"If the women don't find you handsome they should at least find you handy." - Red Green


2012 LT40HDG29 with "Superized" hydraulics,  2 LogRite cant hooks, home-built log arch.

wormy

Hydraulics is the way to go. When I was looking to buy a mill I was going to get a manual mill because I wasn't planning to make a living with a mill. But one of my friends talked me into spending a little more money to get a used lt40 super hydraulic and I'm glad I did. It is hard enough work with a hydraulic mill .why add more work.
    I'm not an engineer or anything nor do I know alot about hydraulics but I always wondered why didn't someone build a mill that the blade ran from a hydraulic motor to reduce bearing load when kicking in the blade.

Den-Den

I am in the beginning stage of building a mill, my goals are:
* Reasonable cost
* Wide cut capability ( ~ 40")
* possibility to add hydraulic functions as budget allows

I have some fabrication skills and will be able to build a machine for less than I could buy one with similar capability.  The money I save will not be much on a per hour basis but I like building things.

I have taken logs to a local guy in the past and his charges are very reasonable.  I have also cut coffee table slabs from crotch sections with a chainsaw, that was not fun and it wasted a lot of wood.  I want to be able to make specialty cuts like that with my mill, do not expect high production rates or lengths over 12 ft.
You may think that you can or may think you can't; either way, you are right.

Banjo picker

Quote from: Jim_Rogers on October 14, 2013, 04:12:49 PM

Most all of the sawmills I have ever seen, have it so that the cut face is rolled over against an upright. And then you cut the second face. This is cutting into a bark face again.
If you could arrange it so that the log rolled so that you were cutting into a cut face then there would be less damage to the blade by cutting into dirt in/on the bark of the tree.

I seem to recall that there was only one mill that was shown at a logging and sawmill equipment trade show that rolled logs this way. And I don't remember the brand name.

I'm sure if I'm wrong about there being only one, that others will post about the ones that do roll logs that way.

Jim Rogers

Cooks.... Banjo
Never explain, your friends don't need it, and your enemies won't believe you any way.

dgdrls

Quote from: Wufnu on October 14, 2013, 02:18:58 PM
Hi,

I'm new to saw mills and am looking to build a bandsaw saw mill within the next year or two.  My background is in mechanical engineering (metalwork, fabrication, repair, etc of jet components, mostly) and, after studying the mechanics, I feel these machines are not beyond the ability of most people to understand and their construction is using methods that have been around for over 100 years.  There is nothing magical about their construction.  I also feel most of the machines out there these days are far too expensive for what you get. 

Frankly, I think I can build a better mouse trap.  stupid_smiley 

The idea I'm germinating is making an inexpensive but modular mill.  As I begin to poke this rabbit hole with a stick, just to see how far it goes, it's immediately apparent that I should consult those that know more than I ever will.  That would be you guys. 

To setup the viewpoint correctly, imagine this: your best ol' friend in the whole world wanted to get a sawmill that was versatile, inexpensive, and durable.  He doesn't fully understand the complexities of milling (thus he isn't sure which features he needs) and is looking to you to help him pick out a mill.  You know he isn't going to get an industrial mill but you don't want him to get junk, either, or a mill that isn't going to be able to handle anything useful.  What features would you look for? 

That is:

What features would you consider must have?


What features would you consider desirable?


What dimensions (max log diameter, bed length, etc) would you figure encompasses 90% of logs most people will encounter?


Basically, I need to be pointed in the right direction on things to research.  I need to know what's important to you, the miller.  I'd like to evaluate all of the dynamics involved in milling, separate the variables, and boil down their functions and how to make them most efficient.  Then, find a way to tie them all in to a modular system that isn't garbage and won't break the bank.  Designed, manufactured, and assembled right here in 'Murica!  Probably at very limited quantities ;)

I realize this may be a bit much but I think I can do it.  Chance favors the prepared mind but fortune also favors the bold.  I don't think those characteristics are mutually exclusive. 

Sorry if this post is too long.  I'd have written a shorter one but I didn't have enough time during lunch break.


Welcome aboard Wufnu,

Interesting thread,  I do think you can build a one-off machine for less $. 
It would be interesting to see just how much can/could be saved
when factoring in labor cost and materials and making a side by side comparison.

Look forward to seeing what you come up with

DGDrls
                     

pineywoods

Wufnu, You are going to find that designing and building your own mill just ain't as simple as it looks. Every piece of a bandmill is a compromise. Changing one thing to get a desired feature will almost always mess up something else. It's a huge juggling act to get a workable design. Example, you desire the blade to enter the log on a cut surface rather than through bark, certainly desireable. Downside, that requires a robust and expensive clamping system to hold the log in place so the blade doesn't pull the log sideways. Also, keep in mind that all the factory built have evolved over many years. (The first woodmizer built in 1983) Changes and added features were frequently suggestions from end users. Not to discourage you, if that's what you want to do, I tip my hat to you. I originally wanted to build my own, but I found a usable used mill for about the same price as materials to build my own...
1995 Wood Mizer LT 40, Liquid cooled kawasaki,homebuilt hydraulics. Homebuilt solar dry kiln.  Woodmaster 718 planner, Kubota M4700 with homemade forks and winch, stihl  028, 029, Ms390
100k bd ft club.Charter member of The Grumpy old Men

drobertson

I may have missed it in all the previous posts, but the question as to portable vs stationary would play a big part.  And will this be a one shot deal? or a possible production build?  Sounds like fun to me, if the funds are available and there's time for fabrication.  Lots of planning for sure,   I'll be watching this one,  be glad to offer any input I can,    david
only have a few chain saws I'm not suppose to use, but will at times, one dog Dolly, pretty good dog, just not sure what for yet,  working on getting the gardening back in order, and kinda thinking on maybe a small bbq bizz,  thinking about it,

Wufnu

Thank you all for the information thus far.  I hope people continue to add what they think is valuable in a mill! 

This thread wasn't so much to debate and select what is "best" but rather so that I can see what options are out there, what is really important, and different design considerations.  I know what I know but, more importantly, I know what I don't know.  That's why I've come here. 

If I've only learned one thing it's that there's more than one way to skin a cat.  I've see so many different ways of doing the same thing.  For example, rolling a log on the sled.  You can use a peavey, a chain, a hydraulic "punch" arm (I don't know what they're called, officially), etc.  I've also come up with a few mechanisms, myself.  Can an inexpensive mechanism be made, that doesn't use hydraulics, to turn a 1500lb log on the sled?  Yes, yes it can.  I enjoy solving problems; they're fun! 

This is why I'm also studying the designs already out there.  Learning from mistakes is one of life's best teachers... but, in my opinion, it's better to learn from the mistakes of others.  The more I view what's already out there, what people want, and new ways of doing things the better a product I can make.  I view this knowledge like tools in a tool box.  The more tools I have, the more I can do and at a higher level of quality. 

I will be doing research for at least a year.  I will use that time to perfect my welding and metalwork capabilities and do more research.  Once I can perform the manufacturing processes at a high level, I will make a saw mill for myself.  I plan to use it to cut wood for a shed (16' x 16').  After that, if the mill is at least "decent", I'll sell it in the classifieds and use the profit (if any) to build another iteration to improve on the first.  Rinse, repeat.  Once I feel I have a quality product, I may begin selling them as a company.  That's a whole other complicated issue and I'll have to think long and hard before going that route.  I do have some advantages that others don't, however, so it's a definite possibility. 

Of course, I may find the margins too thin and just end up buying one.  I have to say, I'm very impressed with the Cooks machines.  I just watched a 40 minute video where one of the founders went over all of the features of one of their mills.  I added quite a few tools to my toolbox with that one.  The machine, at first, seemed overly complex but it was obvious why they were done the way they were.  I appreciate the versatility they've put into their product.  E.g. the electronic lowering/lifting pulleys that can also be turned by hand.  I also like their tensioning system, using a spring constant to get consistent tension.  Simple but effective. 

Speaking of which, if anyone has any digital manuals to their mill, would you PM me or leave a link here?  I'd like to acquire some manuals so I can learn how they are operated, features used on different brands, etc.  That is, of course, if the manual/user agreement doesn't expressly forbid it.  That's a common thing in other industries so might want to check that the manual doesn't forbid you from distributing it, first.  I haven't, thus far, run across any that are posted on the manufacturer's website. 

I'll continue to check in so please continue giving your opinions.  I love'em!  I appreciate that so many of you are keen to see what I come up with.  However, I hope you're a patient lot.  I work at a deliberate pace.  Plus, I have a full time job and lots of "Honey Do" items  :D

Thanks again, everyone!

JP

Wufnu

Oh, I forgot to mention, it would definitely be portable.  Just answering, since someone asked.  The larger machine manufacturers have already made their niche and have found a market with the money to spend.  That type of machine will be far beyond my small scale operation so, for now, it's not even on the radar.  I'm going to stick to the smaller stuff ;)

Brad_S.

Quote from: Banjo picker on October 14, 2013, 08:21:48 PM
Quote from: Jim_Rogers on October 14, 2013, 04:12:49 PM

Most all of the sawmills I have ever seen, have it so that the cut face is rolled over against an upright. And then you cut the second face. This is cutting into a bark face again.
If you could arrange it so that the log rolled so that you were cutting into a cut face then there would be less damage to the blade by cutting into dirt in/on the bark of the tree.

I seem to recall that there was only one mill that was shown at a logging and sawmill equipment trade show that rolled logs this way. And I don't remember the brand name.

I'm sure if I'm wrong about there being only one, that others will post about the ones that do roll logs that way.

Jim Rogers

Cooks.... Banjo
Timber Harvester, the Cook's mill's look-a-like cousin, did as well.
"Life is what happens to you while you're busy making other plans." J. Lennon

jim blodgett

Well, if you're talking bandsaw, there's one thing I think SHOULD be pretty easy to add, that I have never seen on a mill or heard anyone else mention. 

A circular saw mounted on a carriage that slides up and down, and left and right, mounted above the main blade of the saw.

The idea is to set the circular saw to edge one side of the slab you cut off the top of your log as you work down to cant size.  Then of course, that slab with one straight edge could be easilly run through a table saw to whatever width you wanted.

As most bandsaw mills cut now, you have to edge that first straight line some other way, and it takes time.

Wufnu

Good idea, Jim!  I haven't seen that feature, either.  I'd been curious about how one makes boards out of slabs accurately when both sides are rough.  It'd be a challenge to line it up with the band saw blade, though.  Just another problem to figure out!  I like it.  Perhaps there's a reason that the other companies haven't added this feature BUT if it's a feature that will attract customers, who am I to judge? 

Thanks!

JP

Ljohnsaw

Very interesting thread and will be following it.  I'm in the latter stages of my own build.  Upon the strong advice of others here, I build heavy duty.  So heavy, that each of my 16' sections will be about 750# each!  I am building a 4 poster on a 2x4 1/4" steel tube with a 2x3 1/4" angle iron rails.  The head can clear a 52" wide log and my cut width is 42".  Due to my need, I'm making two 16' and one 8' sections so I can mix and match my bed size.  I need some 34' beams and will be doing a lot of 20' stuff.

The biggest complaint I see here is the bunk spacing.  You need bunks close enough for short logs/crotches when you have them.  But, if spaced, say every 4', you have another problem.  If you want to level a long log because of taper, the numerous bunks get in the way.  To level the quickest, you want the TWO bunks towards the center of the log and you only need to raise the low end a little - but the other bunks need to be out of the way.

I "solved" this by copying another idea (forget who at the moment).  I have four bunks that are moveable anywhere on my rails (well, almost anywhere).  If I have a long beam I'm making, I can support it with all four.  If I'm leveling a log, I'll only use two.

Well, that's the plan, anyhow.

My last task is to finalize the blade tension system.  I want to have a "quick release" so I can set it once but release it at the end of the day and reset the next day with a flip of a lever.  At least I think that would be a time saver...
John Sawicky

Just North-East of Sacramento...

SkyTrak 9038, Ford 545D FEL, Davis Little Monster backhoe, Case 16+4 Trencher, Home Built 42" capacity/36" cut Bandmill up to 54' long - using it all to build a timber frame cabin.

Brucer

Quote from: Wufnu on October 14, 2013, 02:18:58 PM

What features would you consider must have?
What features would you consider desirable?
What dimensions (max log diameter, bed length, etc) would you figure encompasses 90% of logs most people will encounter?


Before I can give you any meaningful answers I need to know what your business model is going to be. Full time to earn a living, part time to earn some extra cash, hobby work for yourself? Where are you? What products might you want to make on it? What shape are you in?
Bruce    LT40HDG28 bandsaw
"Complex problems have simple, easy to understand wrong answers."

Ianab

QuoteWhat dimensions (max log diameter, bed length, etc) would you figure encompasses 90% of logs most people will encounter?

Depends where you live. Some places trees barely grow to 12" dbh. Locally we can have cypress and eucalyptus up over 6 ft dia, or 6" cedar top logs...

But as mentioned mill designs are compromises. With a band mill, increasing the throat width means you need to increase the blade tension, that means a stronger heavier frame, and then a wider band to handle the extra stress. Then you need a bed that will support (and turn?) those monster logs. Pretty soon you end up with a WM1000, which isn't cheap, or exactly portable any more.

Ian
Weekend warrior, Peterson JP test pilot, Dolmar 7900 and Stihl MS310 saws and  the usual collection of power tools :)

customsawyer

I am not trying to discourage you on this. Several years back I was needing a small trailer for hauling my lawnmower. Not a complicated build by any means. After several weeks of investigating I discovered that I would spend more in material than I would to buy a trailer already built. :o The reason for this is that the companies that build trailers buy their material in bulk and get a discount. This might be one thing to consider when building a sawmill. You might be better off to buy a used mill and modify it than to build one from scratch.
Two LT70s, Nyle L200 kiln, 4 head Pinheiro planer, 30" double surface Cantek planer, Lucas dedicated slabber, Slabmizer, and enough rolling stock and chainsaws to keep it all running.
www.thecustomsawyer.com

thecfarm

ljohnsaw,the rails on what you are building sounds like my Thomas,right down to the moveable bunk. Good job.
Model 6020-20hp Manual Thomas bandsaw,TC40A 4wd 40 hp New Holland tractor, 450 Norse Winch, Heatmor 400 OWB,YCC 1978-79

Seaman

Like Ianab and someone else said, depends on your business model and what size logs you will be dealing with.



 




 


I honestly can not envision a better mill FOR WHAT I DO than the LUCAS.I cannot see building such a mill for less than it cost, but then I am not a mechanical guru either.

It can cut slabs or lumber from trees 6ft dia. and who know how long with extra post and rails.
Cut and edge boards without resawing
Plane these massive slabs
Sand same slabs
Cut beveled siding
Is portable in a pickup
Easy to maintain
Quarter saw without quartering the log

I am sure I left something out that I am not familiar with.
With the size logs I normally cut we don't concern ourselves with kerf so much
I am not trying to start the band-swingmill debate, and I think this is a great thread, but you asked for opinions.
Good luck with your research, I am sure you can design and build exactly what you want with a lot of hard work. Looking forward to following the thread.
Frank   
Lucas dedicated slabber
Woodmizer LT40HD
John Deere 5310 W/ FEL
Semper Fi

nk14zp

This is my dream saw mill and it's homemade.(And no it's not mine.)
http://www.youtube.com/watch?v=Uz-XBqyfbsk

Uploaded on Oct 17, 2011
Portable, circular sawmill with 48" headsaw, 26" topsaw and 14" vertcal edgers. 100% self contained with 230hp JD power unit; live deck in and out; hyd folding wings; 3 hyd leveling legs (always remains on flat plane); self digging wheels (hydraulically digs itself into the ground for comfortable working height). Quick set-up time (under 30 minutes). Unit weight 24,000 lbs.
Belsaw 36/18 duplex mill.
Belsaw 802 edger.
http://belsawsawmills.freeforums.org/

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