mobile dimension ?

[Beetlekill]

Hello all-  I am pondering the purchase of a 92' mobile dimension 128 on a single axle mobile trailer.  I have a homebuilt bandsaw but am looking for some more production.  I checked out the mill and it has obviously been sitting for awhile.  Normal surface rust, etc.  What should the track look like when sighted down the length?  On the heavier side with the gear teeth it seemed to dip slightly around 2/3 the way down and the lighter side seemed to have quite a few little ripples along the entire length.  Is this normal?  Thanks for any input on what to look for.

[StorminN]

Hi Beetlekill,

Welcome to the forum!

First thing, the dip 2/3rd's the way down... is this at a seam where two sections of track are bolted together? With that vintage of MD 128, I'm guessing it's probably got tension rods running diagonally up and down through the truss frame... does it? These rods can be adjusted with the nuts on the angle irons at the bottom of the track. As long as the track itself isn't actually bent, the track can be unbolted and adjusted (leveled out) and the tension rods tensioned to straighten it out... sometimes guys move those mills by picking them up with chains, or loading them with a self-loading log truck, and if they're not careful, things can get bashed around (don't ask me how I know this). I've also heard some talk of the bolts that bolt the track sections together stretching a bit, which would help cause a dip in the track.

What you want to look for in terms of wear is bearings, first of all. The good news is they can all be replaced, most of them without too much trouble.

Next on the list is the track itself... on the "heavy" side of the track, as you call it... the mill carriage runs on two shouldered rollers... there should not be much side-to-side slop between these rollers and the width of that angle iron on the track that they run on... IIRC, about 0.005" is acceptable... anything more, and either the track is worn, or the rollers are worn, or both. It's usually not a big deal, though. Mobile Mfg. sells oversized (or, rather undersized... depends how you look at it) rollers, to use on worn tracks. My friend recently installed some undersized rollers on his mill to tighten things up.

(However... once the track is worn with more than about 0.020" variation from one spot to another (ie., the head end vs. the middle), it has to be replaced... but this takes a long while... I was recently at the MDS factory and looked at a 1973? mill they had in for repair, I was told it had sawn about six million board feet of lumber, and it was getting time for a new track)

So look at the carriage rollers, look at the cam follower rollers on the "light" (left) side. The vertical gap between these rollers and the track can be adjusted, but make sure the rollers are freed up and turning.

Next, try and see if there's any play in the feedworks mechanism... this is the chain and gear drive that engages the rack teeth on the truss and powers the mill down the track. If the mill has been out in the weather, the bearings in this might be rusted or seized up.

Then of course, there's the motor. Make sure no water is in the oil. (While you're at it, make sure there's no water in the hydraulic motor reservior, either.) If you bother to see if the engine runs, you might as well do a compression check (however, these 1600's aren't susceptible to the hot cylinder syndrome normally seen in VW buses and such.) If the motor was left with fuel in the carb, you might have to clean / rebuild the carb. If you buy the mill without running it, and want to feel good about things, pull the exhaust manifolds off and knock any rust out of the mufflers before you start it up. The mufflers are above the engine, and I've heard guys talk about a risk of rust getting in the exhaust valves if this isn't done.

Now... having said all this, you should know that I knew none of this when I bought my mill (1971 MD 127), and my mill was in pieces with little alders growing up through it... (and of course the MD 127 is belt drive, so it has a bunch more bearings and belts than an MD 128). However, I got a manual, and got in touch with Ron at Mobile Mfg. and started putting things back together and replacing some parts and bearings and such, and it turned out to be a nice little restoration project (that's still ongoing...). In the meantime, I've milled a bunch of wood with the mill, and it keeps getting better all the time.

Good luck with you decision... and if you post some good pictures here, it will help us give you more info on what to look at closer...

-Norm.

[DanG]

No, dips and ripples in the track are not normal.  It sounds like that one has been damaged somehow.  As Norm said, you might be able to adjust that dip out of it and make it saw ok.  If the mill is cheap enough, you could replace the track and still come out ok.  If you can get the serial #, you can call the factory and get the history of that mill.   www.mobilemfg.com

[Beetlekill]

Hey guys - thanks for the input.  This mill did have the tensioning rods so that may help.  The price a 7,500 seems a bit steep but the guy said it was cutting last fall so it think the engine will run without too much tinkerin'.  I had my 1 and 3 year old with me so I didn't get to dig in as much as I would of liked to.  When I do, I will take pics and try to post.  The mill has a 24 volt raising system but he said the bearings were going. 
     I'm still trying to decide if a MD is for me.  Basically I'm at the north of of the coastal temperate rainforest.  The big Sitkas arent as big and hybridize with the white spruce to form what they call Lutz spruce.  Diameters I will be sawing range from 14 to around 26"  some over 30".  I make alot of box heart timbers because of sizes.  How does the MD do at making timbers?  I've only seen one in action on you tube and through their website and I can tell they are great at slicing up big logs into 1x and 2x.  I recently got over 100 good logs but they got quite a bit of mud on them.  My thinking was the MD would be able to hog through these quicker than the band and not be so affected by the fact that they are not totally clean.  Thanks, Brian   

[karl]

All real good advice.
I'd take a real close look at the track- small dings most likely can be massaged out without distorting the track, maybe the dips too if'n you know what yer doin'......

I want to emphasize the advice about pulling the mufflers and clearing rust and shards...not sure where but there is a thread with me whining considerably about having learned that lesson..... but experience IS the best teacher ;)

There are hundreds of things that could be worn, seized,out of adjustment, or just plain abused just like most other used machinery.
We paid 6G for our '82 about 8 yrs ago. It had been sitting for several years, we used about a gallon of Rust Reaper on everything that should move and had only a couple of bearings go out in the first months we used it. MD tracks their machines by ser# so they can give you history and provide manuals etc.

The MD will cut up to 8 1/4x12 1/4 quite accurately, I have sawn larger dimension by rolling the cant...but with less accuracy. MD's don't have the ability to lift the log to the point that the machine saws paralell to the heart vertically- I have on occasion raised one end of th carraige to accomplish  boxed centers on both ends, it is time consuming though unless you can group your logs as to dia, length, direction of taper.

I prefer our MD for cants, then to the resaw for boards.
Yes, the bits are more forgiving of dirt than bands. Doesn't mean I like to see dirty logs coming into the mill though :

At some point (usually in your learning curve :)you may need to have one or both blades hammered for flatness...We finally bought a spare for those times, but if'n you stay on top of bits and don't have a bunch of logs with tons of stress in 'em you shouldn't overheat the blades .

Good luck, and welcometo the forum.

[DanG]

That price doesn't sound too bad, Beetle, considering that you're in Alaska.  I would think that there isn't a mill for sale on every street corner up there, and that would drive the price up a bit.  I paid $9,000 for my '86 model 128, eight years ago, but I was able to check it out in operating condition and actually saw with it first.  If I was in your situation, I'd be telling the guy, "Let's get this thing running and see how she saws", or I'd be expecting a significant reduction in price.  The "dip and ripples" you described are a concern for me.  How severe are they?  The dip could be nothing more than a rusty bolt or two.  I'm not quite sure what the "ripples" are.  I sighted down my track beam today, and the upper beam appears to be absolutely flat.  Along the left side, away from the saw, there is some irregularity that I would describe more as "waves", where the outer bearings have worn down the angle iron in places.  A lot of that probably happened when I had a frozen outer bearing that I hadn't noticed until it started causing problems.  It looks kinda bad when you sight down it, but doesn't seem to affect the lumber at all.

[backwoods sawyer]

Not to down play the mobile dimension, or sell you on the idea of a bandmill but more to give you info....
Today I was sawing Doug fir logs that were caked in mud. (I wish the frosting on my cakes were as thick) I put a freshly sharpened 10* band on in the morning, it was starting feel dull after 1,200 bft. The second band was still cutting strong after another 1,200bft. I do have the debarker on my mill or my bands would not have lasted near as long under those cutting conditions.

[StorminN]

I have on occasion raised one end of th carraige to accomplish  boxed centers on both ends, it is time consuming though unless you can group your logs as to dia, length, direction of taper.

Karl, I have wondered about this one myself... I don't see a reason that one couldn't install a disengage mechanism on the square tube that ties the up/down drive from the head endstand to the tail endstand, the same way the disengage is used on the rack & pinion left/right feed. You would have to remember how many turns you offset them, or lower the mill to the bottom stops to even things back out.

I have thought of trying this, but I always just end up putting a wedge or a hydraulic jack under one end of the log and taking the taper out that way... someday, if I ever get around to installing hydraulics (loader), I'll add a hydraulic roller toe board as part of that.

-N.

[DanG]

I've done that a number of times too, and have been thinking of adding a lever of some sort to disconnect it.  It's kind of a pain to get it back level again, but not too bad.  I just measure the height at the far end, then adjust the near end to it.

[oakiemac]

Beatlekill,

I cant add anymore info then what has already been expertly said. I would emphasize calling MD and talking with Ron about things. Sawmill John here on the forum used to work for them and he might put his two cents in as well.

Just for comparison, I bought my 1997 model 12 with trailer and only 40 hours on engine for $10K back in 2003. It had not been used in years because the owner had died and his kids had just left it sit outside but had the engine in a garage. I had to free up every bushing like the ones on the top of the endstands. I also sandblasted and repainted the enitre mill. Took a few weeks but was worth it.

I think that the MD will do a better job on the mud but I havent run a band mill so I cant say for certain. Cutting cants is where this mill excels. I just cut about 4Mbf of 9X6X18' of white pine cants. Sometimes the mill return would not have enough power to push the big cant back to me so I would have to have help pushing it back and loading it on the stacks, but other wise she cut right through.

Good luck and keep us posted.

[StorminN]

Just for comparison, I bought my 1997 model 12 with trailer and only 40 hours on engine for $10K back in 2003.

Is this a typo? I thought MD stopped making the Model 12 in the early 1970's?

-Norm.

[DanG]

I believe that's a typo, Norm.  I'm pretty sure Oakiemac's mill is a 128.

My opinion is that if you can get a 128 in good shape for under $10,000, including any repairs you have to make, you have done pretty well.  You may be able to do better if you just stumble onto the right deal.  You may not do as well if you're in an area where mills of any kind are not that easy to find.

[oakiemac]

pretty sure it is a model 12. I have converted it to the larger edger blade so does that now make it a model 128?
I'll check tomorrow and see what it says on the mill.

[StorminN]

I have converted it to the larger edger blade so does that now make it a model 128?

No, I don't think so. I meant to get a clarification on the different models and when they were made when I was down at Mobile Mfg. a couple of weeks ago. While I was there, Ron showed me some pictures of the very early MD's in the early 1960's, it sure was interesting. He had one newspaper clipping framed from the mid 60's and he said the day after that paper came out in Portland, Weyerhaeuser banned the transport of milled lumber on any of its private roads... interesting indeed.

AFAIK, (and I hope Sawmill_John will chime in here and correct my gaping mistakes): The Model 12 was the early model with the VW motor, not sure of its capacity. The 127 followed that, maybe 1969-1970? and was all belt driven, and had a 7"+ x 12"+ capacity, with the larger edger blade installed. My MD 127 is a 1971. The 128 followed up in the early 1980's? and I'm not sure if all 128's are hydrostatic drive or not, but all the ones I've seen are. They have an 8"+ x 12"+ capacity with the larger edger blade. So if your mill is from 1994 I'd assume it's hydrostatic, and I'd assume it's a 128.

-N.