I have an older model manual woodmizer LT40. I saw mostly 4/4 barn boards. I don't off-bear, just saw the whole cant by dropping lower on each pass, leaving the previously sawn boards on top. this requires a lot of up-down travel of the saw head. Doesn't take much off that to start wishing for UP that goes as fast as down. Here's a cheap simple fix that requires no modification to the mill.
Here's the parts---
(https://forestryforum.com/gallery/albums/userpics/14000/up1.jpg)
A stretch type garage door spring, 4 ft of 3/16 steel cable, and a bracket made of 1ft piece of 2 inch pipe and 2X2 angle. 2 pulleysare bolted to the angle iron. I used what I had in the shop, clothes line pulleys would work fine.
The whole works fits in the top of therear tower like this..
(https://forestryforum.com/gallery/albums/userpics/14000/up6.jpg)
One end of the cable attaches to the head by threading through a hole here..
(https://forestryforum.com/gallery/albums/userpics/14000/up5.jpg)
The cable goes over the pulleys and attaches to the upper end of the garage door spring. Bottom of the spring attaches to the head hold-down loop like this
(https://forestryforum.com/gallery/albums/userpics/14000/up3.jpg)
Works like a champ...cost zilch if you have a decent junk pile...
Ingenious design and out of the way too.
I couldn't live without my junk pile.
Looks great! Besides going up faster, I bet it takes a lot of strain off of the up/down chain and drive system.
Just wished you'd thought to add your post to the "Usefull Sawmill Mods". :'(
There's an added benefit that I didn't mention. It cuts the current drain of the lift motor about in half, saving some precious amps for another project I have in the works.
One thing I'd probably do is slip a piece of PVC or the like over the spring. I'd hate to get some pink body part stuck in it as it retracted. yikes_smiley
Say, maybe the spring could be dropped down inside one of the frame tubes? Ya'think?
. from Bibby Say, maybe the spring could be dropped down inside one of the frame tubes? Ya'think?
.
Be easy enough to do that, I'd have to clean the old dirt dauber nests out of the tube :o
Already found one unusal side effect... at certain hights, the spring resonates with the vibrations of the motor and it twangs like a plucked getar string ;D Bet I have the only musical mizer ;D
Maybe that's why WM uses air springs to counter the weight of the head on the LT15?
Drop a safety cable down the center of the garage door spring, just so it contains the pieces can fly everywhere when (if) the spring reaches the fatigue level and fails.
A neighbor narrowly missed a face make-over when one of his springs failed, and it only took a chunk out of his ear.
Hiding it in the tube is good too.
I don't even have a band mill, but I still enjoy reading about how folks fix problems or make things better. That was a great idea there pineywoods 8) Thanks for sharing.
Like Bibby said, Wood-Mizer uses a Gas charged shock as an assist for the LT10, LT15 and the LT70D. The electric LT70 does not need the assist. The LT70 assist is in the Mast or tube like you guys are talking about.
I like the spring idea.
Marty
I get frustrated with the slow up/down on our manual LT40 as well. I discovered that you can just reverse and slide the blade under the board and then drop down for the next cut. Sometimes you do have to hold the board so it doesn't slide off, but it works really well. If I am sawing a lot of 4/4, especially short and narrow stuff, I like to saw several boards and then tail them, as I have to carry them outside, it really saves a lot of time. When I have someone tailing for me, they better hurry up get back inside and get the next board, because I don't stop sawing except to turn the log. Unless they need help with a heavy slab.
I know I have some drag issues to work out with the gasser, as it is way slower than the electric, but when I get them addressed I am going to look into this setup. Thanks pineywoods.
Dave
I've found that sawmilling is like wanting a faster car. If I win the lottery, I'll have a nitro powered sawmill!
Quote from: Dan_Shade on August 24, 2007, 07:50:42 PM
I've found that sawmilling is like wanting a faster car. If I win the lottery, I'll have a nitro powered sawmill!
I know what you mean, but lately I have been paying close attention to where my time bottlenecks are. I saw by myself, and material handling (logs, slabs, lumber, sawdust) is by far my big time sink. Sometimes I think I could triple my output if I could cut my handling time in half.
Thanks Pineywoods, thats a mod I can definatley (sp) use.
An improvement update. After using the spring assist, I came up with an improvement. When the head was higher than about 18 inches, the extra lift wasn't much. Added a pulley and another spring. Both springs attach to the bottom of the pulley bracket. More lift and it's consistent over the full range of head travel.
(https://forestryforum.com/gallery/albums/userpics/14000/2springs.jpg)
On my particular mill, the down is faster than I would like. It seems the minimum drop I can do is about an inch. Does this modification make the down action more controllable?
Quote from: Ocklawahaboy on January 15, 2013, 02:59:55 PM
On my particular mill, the down is faster than I would like. It seems the minimum drop I can do is about an inch. Does this modification make the down action more controllable?
Nope, won't help much, BUT, Like everything else involving a sawmill, there is a learning curve. Trying to stop the head where you want it when dropping down is an iffy situation at best. There's too many variables. IE water tank and fuel tank empty or full? When was the last time the rails were lubed? What most of us do is try to stop somewhere close but a bit lower than the desired point. Then jog back upward in short bursts..The accuset /simple setworks option adds electronic speed control to the head up/down motor so it can stop exactly where needed.
However there's a little more to it. Likely, here's what's going on. The up/down drum switch has an extra set of contacts that are closed when the control handle is in the neutral position. They short across the motor, causing it to act like an electrical brake. If that contact is not functioning, what you will see is the head may coast down 2 or 3 inches after you release the handle. Normally the head should stop downward travel within 1/4 to 1/2 inch after releasing the handle. Fix is easy enough, pull the cover off the control box and adjust or clean the contacts so they close completely with the handle in the neutral position. Only one set of contacts involved. All the others should be open
Thanks for posting your 2-spring mod, Piney!
Can't really tell, but is the second spring inside the main "garage door spring"?
With the sawhead all the way down, how far up would you stretch the spring before connecting the cable clamp?
[quote author=Chuck White link=topic=27272.msg938995#msg938995 date=1358287996
Can't really tell, but is the second spring inside the main "garage door spring"?
With the sawhead all the way down, how far up would you stretch the spring before connecting the cable clamp?
[/quote]
Nah, nothing so sophisticated, the 2 springs are side by side, just alike, matter of fact, they both came off the same garage door ;) That's where the pulley came from also.
I cheated on the hookup. Raise the head all the way UP, the pull some pressure on the springs. They will stretch some more when you lower the head. Might be advisable to string a piece of small cable through the center of the springs, leave it loose and fasten each end securely. Serves no functional purpose, but will retain the pieces if one of the springs breaks.
Thanks Piney, I really appreciate your post!
Well, I finally got pics of the Pineywoods lift-assist mod!
Top of Lift-Assist
(https://forestryforum.com/gallery/albums/userpics/17517/2013-03-31_17_35_18.jpg)
Bottom of Lift-Assist
(https://forestryforum.com/gallery/albums/userpics/17517/2013-03-31_17_36_04.jpg)
Pineywoods Lift-Assist
(https://forestryforum.com/gallery/albums/userpics/17517/2013-03-31_17_35_46.jpg)
Nothing at all difficult about this mill-mod!
Thank you Pineywoods
How old does your mill have to be to use this mod? ;D My LT40 is a 2006 and at the moment I don't have either the simple setworks or Accuset. I hope to upgrade to one of these in future. Do you think there is still value in adding the spring(s)? Will this mod interfer with simpleset or accuset?
Probably wouldn't do much for the newer woodmizers. The older mills had no external alternator, depended on the small alternator built into the motor flywheel. With limited electrical supply, the up/down and feed motors are small to keep the current drain to a minimum. Don't know what year the changeover to external alternators and bigger head motors was made, my guess would be `1997. This mod has the effect of reducing the head weight by 50-100 pounds, thus making life easier and faster for the head up/down mechanism.
My mill has a 105amp automotive alternator.
The reason I added the Pineywoods assist kit was I was going through a couple of sets of up/dn motor brushes per year!
The previous owner installed the debarker (which I just love) and it added quite a bit of weight to the sawhead, therefore causing more draw to the up/dn motor!
If your up/down goes slower than mine, then I can certainly see why you did this mod! :o
I do have the external alternator. I was thinking of adding the mod to hopefully speed things along on the upwards movement. The manual up/down crank of the LT28 was much, much faster! Yes it took a little effort, but only a few seconds (even for large movements). I also like the idea of relieving the load on the motor a bit.
I'm not sure if the up/down motor of the super hydraulic will fit or not. Maybe that is the way to go instead.
I looked into upgrading my electrical/hydraulic system to match a super a few years ago.
the alternator and battery are bigger to supply the needed power.
The single spring mod helps a bunch, but the 2 spring version is even better. More lift and it's more consistent across the full range. Another thing I noticed is it's a bunch easier to stop on the mark when dropping down...
I'll most likely end up adding another spring.
Probably just go buy 2, then they'll be of the same tension.
Thanks again Piney
I was looking at doing this mod to my mill as well. I have a 95 and it has an external alternator. I have looked at springs at the local ACE and they have several sizes and are rated for different weights/loads. I realize you both used springs from your 'piles' but if you could tell me the length and diameter of the springs you guys used I could compare that with what's on the shelf. I'm also interested in people's opinions on which safety measure would be better. A cable run through the spring or a piece of PVC around the spring?
Thanks
Victor
Victor, I just used a regular overhead garage door spring.
In the 3rd pic, the spring is double it's relaxed length.
I think that the cable ran down through the length of the spring is just as good as any other safety device.
The primary thing you would normally be concerned with, is pieces of the spring going flying in the event it breaks!
Victor, you might try calling the local garage door company/companies and see if they have used springs from doors they have replaced. Might get them free or at least cheaper than new from Ace.
The 2 springs I used came off an 8 ft wood overhead door. The door was replaced with a metal one, I liberated all the hardware including the defunct electric door opener...
No pics but i mounted a torsion garage spring on mine which was fairly easy. Steve
Good idea with the spring. On my lt30 where your bracket goes in the top of the post is where my water bottle mounts. Where does your water bottle mount?
trapper; My water bottle and gas tank both mount on the (black) shelf that has the wrenches laying on it, right near the top of the sawdust chute in the 3rd pic!
My shelf is only big enough for the gas tank. Need to find a place for the water bottle.
Maybe where I dont have to lift so high to fill it and maybe a smaller water bottle.
I got a question for ya, I have a older lt25 manual ,does it help with the manual up and down ,cuz I did it to my mill and it didnt help , think the garage door spring isnt heavy enough , how thick is the coil stock of the spring and how long is it relaxed , it would be nice if the cranking up was better
thanks alot jim
The spring helps to lift the sawhead!
The spring takes a lot of the strain off of the up/dn motor and both up and down now opperate more smoothly!
I just went out and took measurements on the spring I put on my mill!
Relaxed spring length: 31 inches
Extended spring length:65 inches
Diameter of the spring: 1¾inches
Diameter of the spring material: 1/8 inch
Sorry it took so long to reply.
Ole school bus drivers walk slow. smiley_old_guy
Sometimes Lynn, sometimes! ;)
This simple upgrade has been in place for quite some time and has served me well. After some problems with the up/down motor, I started thinking about the possibility of a larger faster motor. The original is sandwiched between the brake band and head support column, so there's not enough room for a much larger motor. What about the starter motor off the lawnmower? About the same size, but 4 poles instead of 2 so should be twice the torque.. worth a try. Dis-assembled the starter, lifted 2 brush leads from frame ground and routed them out through a hole drilled in the end plate. The slots for the mounting bolts had to be lengthened a bit, and I used a slightly larger v-belt pulley cause that's what I had. Otherwise, pretty much a bolt on operation. Hooked the power leads to the wires from the old motor and hit the up/down switch...WWHHHOOOO BOY, this thing is FAST. About 3 times the speed of the original motor. Looks like factory
(https://forestryforum.com/gallery/albums/userpics/14000/speedup.jpg)
Hey Piney woods
That a real great idea. What model of starter motor did you use? Could you post the specs for us?
Quote from: Bandmill Bandit on August 07, 2016, 11:38:49 AM
Hey Piney woods
That a real great idea. What model of starter motor did you use? Could you post the specs for us?
Junk yard special. It came off a 10 hp tecumseh on a junked riding mower..No markings of any kind..One drawback, which I kinda figured on, is the 15 amp alternator under the flywheel won't quite keep up, so I hook up a battery charger at night..I need to install an automotive belt driven alternator.. another project ::)
Almost all 10 hp tecumseh starters are the same...
(https://forestryforum.com/gallery/albums/userpics/39553/10_hp_tecumseh_starter.jpg?easyrotate_cache=1470615632)