Slabbing Bandmill ??'s and new member introduction

[MSWT]

Hi gents, and first of all, Happy Holidays to everyone!

New member here, I split my time between AZ and MS/GA/NC, traveling and sourcing wood for customers. 

I'm starting this thread to share a project, and get some feedback for those that have done it on some home-made bandmilling equipment.  I've been in the lumber business now for 9 years, selling, milling, and brokering.  I've owned and sold both woodmizer mills and AK mills, the last one was a MS880 and 84" bar.  It cut well, but it was a brute to run, and SLOOOOOOOOOW. 

Anyway, I'm looking for some feedback from you guys/gals out there on a new project, which I am drawing up today/tomorrow/etc.  I need to build a dedicated bandsaw to slab big logs.  I don't need to mess with dimensional stock, or beams, or any of that.  I have a client base now that just needs live-edge, I take good care of them, they take care of me.  I'm done alaska milling, I need to go faster than they will work.  they also waste a hell of a lot of wood.  I hate to think about all the walnut sawdust I've made sometimes.....

I passed up the opportunity to have one built, as I have a lot of mechanical/welding/fab experience on my hands, and tools/equipment as well, and the builder's quality did not impress me at all.  I am trying to keep this build simple, rugged, and well, simple.  Have adequate budget, I'm sold on the idea of a 4-post head, a wide track (currently spec'd at 72" wide x 15' long), and 24-26" bandwheels.  It will be towable, heavily built, and designed to cut slabs, (8/4, 10/4, 12/4) from 25-60" logs, one at a time.  I've got a 7.3L dually to tow it. 

I have located a 25HP subaru engine that runs propane (not converted - those aren't great, just ask me how I know..) so I can use that as a fuel.  I'll suffice it to say I've owned and broken a lot of motors, and am sold fully on propane for industrial uses.  It's also, in my areas of operation, cheaper than gasoline or diesel. 

Burning questions: 

1) I really want to use a 1.75" wide timberwolf band, and rubber tires.  I got this idea from the "angry beaver" mill on lumberjocks - look it up, pretty cool machine, but way more complicated than I need.  Can the rubber tires produce enough tension on the blade to support a 60" cut, or do I need to buy a $1600 set of wheels and make a tensioner on this thing?

2) Has anyone found a 1.125" bore centrifugal clutch that can handle 25HP?  I think I found the end of the internet today, and haven't seen one...barring that, I guess an idler pulley and lever will get it done, one of my woodmizer electrics had that, and it was a simple, yet very effective solution. 

3) Who makes a short axle (20-24") that I can use to mount the drive/idler wheels/tires on this thing and rip up some logs? 

thanks in advance guys, there is an encyclopedic level of knowledge on this site, and I appreciate everyone's contributions. 

- DC

[Den-Den]

1)  I am using rubber tires but can only cut ~40"; it should work for wider cuts but might take fairly high pressure in the tires.  Consider using load range D tires.  You will still need a tension system with tires.

Towing this thing may be interesting; 60" cut, two tires @ 25 - 30" each and a guard will put the width over the legal limit without a permit for each trip (at least in my area).

[fishpharmer]

Welcome to FF!  Sounds like you about got it figured out.  I had custom shaft made on my homemade mill.  Welded a hub to a round shaft and then had the face of the hub turned on a lathe to flatten and true it.  Personally I would recommend more horsepower and preferably a diesel if your going to slab many logs over 40".   Especially if time is an issue. 

What kind of support equipment do you have?  To move those monster logs around?

[MSWT]

Guys,

Feedback much appreciated. I'm figuring width of the head as max legal limit, 102", less a wheel diameter, and a few inches for saw guard.  I figure go big or go home....

About what PSI do you run in those tires?  I'm guessing the crown in them, combined with a guide wheel makes it pretty easy to true the blade or do you need fine tuning?

I'll look into more horsepower down the road, this machine is for slabbing like crazy for a few years and then re power. Right now it's not worth the $5k for a diesel.  With some luck maybe I can find a 30-35hp propane motor down the road.

If you have close up pics of your axle/bearing assemblies, it would be much appreciated!

[mikeb1079]

here may be some ideas:

https://forestryforum.com/board/index.php/topic,76559.0.html

[york]

Hi and welcome,

For starters look at this...

https://forestryforum.com/board/index.php/topic,76559.0.html

[MSWT]

Wow.  That is one hell of a mill!   I really like the design, being really robust and simple - I'll follow his lead! 

I've been at the drawing board most of the day, and mine will probably max out around 52" and will barely squeak by DOT regulations for towing. 

For now, the mobility is important, and if I get that big of a log, I guess I can break out the AK mill again...

I appreciate the link, its helpful, I'm trying to make the axle and drive clutch work now, I have the head and carriage all done - on paper that is...

The forklift will get a workout after this one gets running. 

Anyone who can comment on tire pressure, or axle assemblies will be most appreciated.  I'd like to power this with belt drive off the motor going to the rear of the axle carrying the drive wheel. 

[MSWT]

Also - is there a minimum tire size I can run?  Smaller diameter tires will give me more throat space, but I don't want to break a band with 25hp behind it.

I've found some that are about 24.5" with a 13" rim.  Could i drop down to 20-22"?

[FarmingSawyer]

To keep the width of the unit down for DOT reasons, could you put the wheels inside the frame--like a deck over trailer? You'll still need some strong jack-legs to hold this monster up and level while your milling........

I run a 25hp Honda gas engine on my mill......it rarely bogs down, but I can bring it to a stop if I'm not careful. Recently slabbing some 30" oak with a sharp band, it was crawling along........You should really think of upping the HP for wide cuts. Every time the RPM drops, the band becomes less stable and wants to wander......and as it slows it heats and the tension slips and it wants to wander...... On those wide cuts that band will want to enter the wood and exit the wood at the same rpm without a hiccup.

[MSWT]

Well I'll start sniffing around for a bit bigger motor.  In the meantime, I am stuck on the bandwheel support mechanism.  I wanted to use rubber tires for ease of construction and cost.  I've heard from this post that you need a tensioner in addition to varying the pressure in the tires...How is this done? 

In this post: http://lumberjocks.com/projects/84032, there is a mill with about the same capacity I need, running rubber tires and no additional tensioner that I can see...

Anyone with a tire-based mill want to weigh in on this?  if you have both, why and how did you do it? 

I like their axle design enclosed by flange bearings - I think that is a no-brainer for me.  Now I just have to make the belt drive work, shouldn't be too hard. 

Cooks saw sells a 24" wheel set with bearings, but it's not cheap: http://store.cookssaw.com/sawmill-parts/band-wheels/25-all-metal-band-wheels/25-performance-band-wheel-package.html - ouch!

If that is the better way to go, so be it, but I'd rather do rubber tires and keep this one simple, unless they are a big power drain?

Cheers guys, and keep the advice coming!  I'm excited about getting this one off paper and into the welding shop!

[york]

Hi,think you should give more thought to using tires,trying to pull the band through that much log,will you be able to tension the band,up enough to do the task???

[GAB]

MSWT:
Sorry I do not have any answers for you but I do have some questions.
1.  If you were to mount the saw head at an angle with respect to the axis of the mill bed would that gain you anything?  May need to have a longer trailer.
2.  Is it possible to make the non-drive wheel adjustable so that the mill head is less than 102" for travel and when you are setting it up then put it on the operating position, tighten the band and have at it?
Gerald

[Gasawyer]

Welcome to the forum!  This is something that I have been considering building. The problem in my slabbing that I do in large logs is tramp metal. The chainsaw slabber I currently run is tolerant of some metal and still finish the cut. I wish you luck on your project and to seeing what you decide to build. Happy new years!

[GAmillworker]

Welcome to the FF

If you have the time to look around I would encourage you to look for an older band mill to modify.  they have most of the parts for a fraction of the cost.

This is what I built.
https://forestryforum.com/board/index.php/topic,67692.msg1014291.html#msg1014291

After 48" wide it is challenging even with 2" band on 30" wheels to keep enough tension on the band to cut straight.

My saw has a hydraulic tension-er that i max out at 3,000psi.

In a 60" cut with 30HP 480 three phase motor it is slow go to get a good straight cut.

[Swatson]

Here is my set up.  I only use tension and do not monkey with the tire pressure but I have plenty of adjustment to run a wide range of band length.





The tires help to even out the tension in the band as it warms up...but you are talking about a much different kind of cut.  That wide and the band is gonna heat up quite a bit even with lubrication.  I dont think the tires could make up for that much change.  I would use the hydraulic cylinder with a gauge, that can be adjusted with a hand pump if I were trying to make a cut like that.

[StimW]

You can buy stub axles with hubs at any good trailer supply.
I have replaced the stub axle on 3500 # axles and I know they make the stubs for 6000# too.
As for legal width you could put a boom pole at the front of the trailer and lift the head and turn it sideways and secure it for transportation.

[FarmingSawyer]

Check out any of the videos on Cross Super Sawmill......he claims to have the world record holding biggest bandsaw.....erm....don't know, but it's impressive...... He doesn't seem to have blade guards, tensioner or anything and runs 2 different size bands depending on how wide he's cutting.....

http://youtu.be/AVJ1UarRhEU

[Swatson]

Wow....I dont have words...Is that a whole forklift that makes up part of that?  And looks like a jeep fender...wow... ...I just dont have nothing to say...

[york]

Think,i would just go buy this here thing.....

https://www.youtube.com/watch?v=EMHuKphn29U

[FarmingSawyer]

Think,i would just go buy this here thing.....

https://www.youtube.com/watch?v=EMHuKphn29U

A wondrous machine indeed, marred by complete lack of thought....... Once again a WM machine where the operator gets covered in sawdust.....and has to stand?? And the clamps and log turners chewed the log up....I wouldn't be happy with the aggressive bite they seem to show on a high dollar log with clear faces. And how about a slab unloading arm or something.....or a way of holding a quarter so you can put it back on to quarter saw......

I think for the same money you could probably import one of those slick portable German mills with the over-the-blade cab and complete automation......

[MSWT]

Guys,

thank you all for the feedback!  Yes, I thought about a WM1000, but to set it up right is about $70K...kinda out of the budget right now. 

I'll look around for an old vert mill, or large bandsaw for the wheels, but as of right now, I'm leaning towards the following:

25HP propane - unless I can find a 30.

Rubber tires with screw-tension sliding mechanism, or ~$900 for cook's wheels...

1.5" wide blade - after talking with a few gray-hairs around mills, narrower bands take less energy and don't cup as bad, just require wedging the cut - easy enough.

Bearings, 1.5" shafts, and pulleys from www.thebigbearingstore.com

If possible, idler wheel will detach for transport. 

Towable behind my truck, cutting length to be around 14-15'. 

Up/down by crank. 

manual push.

[MSWT]

Re: slick german mill - I priced out the Afrika, will saw 64" or so, for $120K+taxes and shipping from germany...

out of my price range...

[MSWT]

One more question - can I use 19" wheels on a band that is 18'-ish long? 

Is there some type of formula for wheel size vs. width of cut/blade length?

If no one knows, where could I go to find some help?

[Swatson]

Diameter doesn't have anything to do with width of cut but it does with what thickness of a band you use.  I imagine for the length your looking for it would be a 0.050 and those require some larger diameters to keep from fatiguing metal.  I am not sure if 19 in would be the best for that.

[york]

ok,give this a try......

http://www.lenoxtools.com/Guides/LENOX%20Guide%20to%20Band%20Sawing.pdf

[scor440]

I don't know why the dust dumps on the operator side of WM?

[Dave Shepard]

Would you rather it dumped it on the loading arms and the next log? If you are walking by the head, I don't think it much matters where it's blowing.

[MSWT]

York - helpful stuff for sure, thank you!

I put in a call to suffolk machinery about some blades and wheel sizes as well.  I think I have saw-head engineered, will be using SCH80 pipe in 3" and 2.5" to make a telescoping assembly.  The axles on the ends will be 1.5" and set in 4-bolt flange bearings.  Tensioning via screw-jack and tire pressure. 

The guys with tire-mills:  how did you make sure they ran true to each other?  I can weld square (most of the time) but these are precise things..like, really precise. 

Head will be manual push and manual raise/lower.  Power transmission via belt and cam/lever with idler pulleys.  I'm going to start with my 25hp propane, but am looking into a 3-phase electric/genset option once I get it to GA and sawing.  I have some experience with electrical, and my last 3phase woodmizer, 10HP, would keep pace with a 25hp gas on the dimensional stuff.  Those electrics have torque for days...key will be sourcing a 3PH genset for the right price. 

I hope this thing works, I've got a lot of monster logs to saw.....

[Den-Den]

You need to build in some adjustment capability so that you can tweak the alignment.

[MSWT]

Does anyone have a picture or diagram as to how they did that?  Some close-up shots possibly?

[Magicman]

Welcome to the Forestry Forum MDWT.

[Swatson]

Like Denden said.  You have to leave some adjustments.  Pillow blocks if you use them have some adjustment, you can also drill some holes a little little larger than needed.  Say you are using half inch bolts, drill the plate to 5/8ths.  Shafts can slide in and out.  In my set up the idle side has tracking adjustments, and the drive side I can slide the shaft in and out and move the pillow blocks to get my vertical alignments to make the wheels plane up.  Then my head can be tilted in and out.  Biggest key is dont make wear and tear parts non replaceable.  Use bolts where needed.

[MSWT]

Swatson - very helpful stuff, thank you.  I'm going to have a fixed drive wheel, supported by 2 4-bolt flange bearings.  the idler wheel I'll make adjustable to fit the drive wheel I think. 

Did you just weld that hub to the driveshaft?  It's what i was thinking of doing unless i can make one from some 1/4" plate and weld on a keyed collar, I'd just have to get it trued on a lathe - I don't have one.   

Re: tensioning, has anyone used airbags?  I have a set of those AirSprings left over from another project, and they put out some force when they're loaded, and have about 5" of travel.  They also inflate with a bike pump in about 30 seconds.  They seem a little more forgiving then a screw-jack method, and are replaceable as all get-out. 

[Swatson]

The hub on the drive side is not welded to the shaft.  I used two weld on hubs (the kind you use for weld on pulleys) and put them in both sides of the hub.  I took the bearings out of the hub.  The weld on hubs had to be turned a smidge to fit.  Nothing fancy to turn them, I just mounted them on the shaft and hit them with an angle grinder while they were turning.  The weld on hubs have keyways cut into them. 

[Swatson]

Did you just weld that hub to the driveshaft?  It's what i was thinking of doing unless i can make one from some 1/4" plate and weld on a keyed collar, I'd just have to get it trued on a lathe - I don't have one.   

I would not use 1/4 inch plate here.  I would look at 1/2 inch.  There is a lot of stress from the band pulling on the tire. There is a big difference in strength between plate steel and cast iron.  The tire works kinda like a cheater bar on the hub and I would be afraid it would bend 1/4 plate.   And if I did use plate and a collar I would make triangular buttresses to weld to plate and collar.

[FarmingSawyer]

Would you rather it dumped it on the loading arms and the next log? If you are walking by the head, I don't think it much matters where it's blowing.

Just move the operator to the other side....keep sawdust where it is, and give him a plexigass screen on the dust side. And if he's got to ride a long, give him a seat! It's not like he's got to step out and help turn the log!!

[Dave Shepard]

So you want the operator to walk over the loading arms and the next log? It's all about compromise. Like I said, if the wind is right, then it doesn't matter which side the operator is on, you are going to eat sawdust. If you can't be in the dust, then you need a remote station. As the options increase, so does the price. If you want an inexpensive mill, then you are going to have to push the head, and be in the sawdust. If you've got $80k to spend, you can get a climate controlled sawbooth.

[FarmingSawyer]

If you've got $80k to spend, you can get a climate controlled sawbooth.

That was kinda my point...that WM1000 costs upwards of that. If I was going to spend that much, I would be thinking hard about those options. I do push my mill from the loading side.....away from the sawdust chute. Works great. Rarely take a sawdust bath. Being on the loading side of the mill helps me see the logs coming up and think about how I'm going to put them on the mill before they get there. I'm not sure I could get used to looking through, or over or around the headsaw rig to check the deck--be it a stack of logs on the ground or trailer or a dead rolls.

When I was offbarer on a circular mill my station was across from the live deck. I used to play a game of trying to think through what the sawyer was going to cut out of any given log. I got better as the years went on. It also helped me know which bin I was going to dump material in and whether I had time to edge AND stack the 1x before getting back to the headsaw to collect the 2x or beams.....

[mikeb1079]

at first i too was curious why the dust exits on the operators side on a mill such as a wm.  then i got one and realized that there's no choice.  you can't pile sawdust on the loading side and you can't operate from that side either.  the hydraulic loader arms-which most guys use to hold slabs that will soon be edged-are in the way.  even if the arms were down it would be too much of a trip hazard having to step over them every forward and rearward pass.  anyways, it's not that big of a deal.

back to the original thread: 

i know you've got to use what you've got but my suspicion is that you're gonna be waaay underpowered to slab 5' with 25hp.  50-60hp diesel would be much more appropriate to the task.  if i were in your shoes i would bite the bullet and purchase the large cook's wheels.  yes they're alot of money but if you're milling huge slabs the return should be quick.  also, i think the steel wheels would better handle the extreme tension you're gonna have to run.

[MSWT]

Ok gents, got some progress, and inevitably, more questions.  Saw head will be made of SCH80 steel pipe, and telescoping.  Tension will be via two airbag springs from a 350 truck kit.  Spoke to timberwolf blade rep, he was extremely helpful, will try and run a 1.5" wide 0.052 blade on this sucker.  Rumor has it they cup less in wide cuts... 

Re: power - I have found two options, one being a 4 cyl Isuzu diesel which I can buy cheap - I love the idea but it might be too heavy.  Option 2 would be a VW bug motor.  Option 3 would be a D series motor from a honda civic, have a good friend who is rice-car builder and can get me a solid 110hp standalone motor that weighs less than 300lbs....

Saw frame is thick-wall 2x6 square tube with 2x8 cross supports to deal with giant logs.  Will possibly put I-beams underneath after flex is measured. 

Going to use Pneumatic tires.  Can't justify cost of $2K+ for wheels right now. 

Questions:  Blade guides - I was looking at Cook's or Woodmizer's guides.  Any preferences out there?

Blade tracking - is there a primer course on how this is done?  i've got an 8-way adjustable coupling between idler wheel and frame, so adjusting that will be pretty easy, but I need to know how to make that SOB track straight.  I understand the crown of the tires will help a lot, but unsure after that. 

Thanks guys, have lots of parts on order, will get some pictures/website up once I get to welding and bolting!  This place is very helpful.