Hello I have been putting a circular saw mill back to operation and i realize how little i know. i picked up this sawmill at a presumed great price i have repaired all the components. The carriage has four air cylinders that operate the dogs which i replaced the seals now they do bite. the Carriage also has a gear driven forward advance system which i have replaced the motor. The Mandrel "if im using the term properly" was once driven by a PTO off a tractor. upon backing up my tractor to size the drive shaft i realized rotation was an issue. subsequently i decided to purchase a power unit for it "Detroit Diesel 371. it has a clutch system and belt drive. I am planning on mating them this week. it is looking like i am getting to the end of the line where it may be go time. i have one tooth on my blade that is missing i have determined that shank is a type F but am unable to determine the tooth type/size.
If there is anyone out there that has any pointers i would greatly appreciate any input and comments
few questions on Power unit should i belt drive it to adjust rpm at PU to rpm at saw blade? or put drive shaft on the unit?
Off-site photo link removed by Admin. here i set mill on mountain
Off-site photo link removed by Admin. here finished repairs and building deck this is where i figure rotation is contra to what i need. i go pwer unit shopping found a 371
Belt drive seems safer/easier on the motor than a shaft... I'm sure you've already read about setting lead on the blade and have researched the rpm the blade was hammered for?
i was not sure of what the blade was hammered for? would there be a mark on the blade?
thanks for the opinion on the Belt V shaft
In general, belts transmit power with a slippage limitation that is its own sort of clutch, however that comes with a sideloading on the shaft and crank bearings to keep belt tension. And enough rigidity to maintain alignment to prevent a thrown belt is also necessary.
Shafts need a clutch mechanism installed if take off power must be fused to protect components. They dont need the alignment precision of belting and they distribute a more even load concentrically about the bearing races, but they do cost some money to buy and take more maintenance in terms of joint greasing and replacement, spline wear and so forth.
Either can obviously work to power the saw arbor, just need to choose which method youd rather put up with. Either is happy to remove digits for you so think safety screen.
If i understand overall; shaft drive is somewhat the better choice. the Power unit i have is a 371 Detroit Diesel with a Detroit Diesel Allison PTO it has a clutch, would this suffice my clutch requirement for a shaft drive. this engine has low idle at 625-650rpm i m thinking my blade speed should be around that is there any consideration there with that issue.
thanks for your time and Information
Bill
Bill, you will get little power from a 371 Detroit at what is idle speed. You will need belts and pulleys to run your engine at 1800 or so RPM's and around 600 at the arbor, a three to one ratio. Just starting out it would be best to have your saw tension checked and a new set of bits. Frank C.
Most hand mills in my area run at 540 RPM. I worked in one mill where the owner wouldn't get his speed up to that and the diesel run at an idle. Very hard to cut any wood.
As for shanks, you should be able to get them from a sawmill supply shop. I don't know if there are any neighboring mills, but they might have a used one or two to give you. F style is pretty common.
Did you get a saw wrench to change your teeth?
My neighbor just gave me 3 rusty saw blades for decoration that are peculiar. They go on a pretty large 3 bolt hub and have slots into the main body with brazed carbide inserts that must create a planing or clearing action against the log face as they pass by. Ever seen those? Theyre a curious thing to stare at.
I see alot of ppl talking about powering circle sawmills with belts and shafts and getting the rpm's right has anyone ever just used a manual transmission with clutch coming straight off the engine? I would think it would be the best way to set speed. just have to have the right gear and the right rpm's then also be easy to disengage the drive and not have to shut the engine down
Quote from: Crusarius on September 27, 2018, 03:57:04 PM
I see alot of ppl talking about powering circle sawmills with belts and shafts and getting the rpm's right has anyone ever just used a manual transmission with clutch coming straight off the engine? I would think it would be the best way to set speed. just have to have the right gear and the right rpm's then also be easy to disengage the drive and not have to shut the engine down
I've seen a few of those on YouTube.... but there's lots of things on YouTube.
Quote from: mike_belben on September 26, 2018, 08:11:27 AM
My neighbor just gave me 3 rusty saw blades for decoration that are peculiar. They go on a pretty large 3 bolt hub and have slots into the main body with brazed carbide inserts that must create a planing or clearing action against the log face as they pass by. Ever seen those? Theyre a curious thing to stare at.
You don't mention the diameter but most edger saws have a big eye with 3 bolt holes. Slots in the rim are to give the rim room to expand if it gets warm.
Crusarius, driving a mill from an engine and transmission is very doable. I have seen an old Chevy truck with the rear end removed and the drive shaft hooked to the arbor. A weak link is needed be it belts shear bolt or slip clutch. The old boy with the truck drive had a warm cab to sit and have his lunch. Frank C.
never thought of the warm place for lunch and relax. that would be nice.
Slip clutch be real easy to put on there. My dad put one on his bush hog.
Quote from: moodnacreek on September 27, 2018, 05:42:10 PM
Quote from: mike_belben on September 26, 2018, 08:11:27 AM
My neighbor just gave me 3 rusty saw blades for decoration that are peculiar. They go on a pretty large 3 bolt hub and have slots into the main body with brazed carbide inserts that must create a planing or clearing action against the log face as they pass by. Ever seen those? Theyre a curious thing to stare at.
You don't mention the diameter but most edger saws have a big eye with 3 bolt holes. Slots in the rim are to give the rim room to expand if it gets warm.
That might be it. Ill get some pics when i go get em. Theyre all rusted. Probably just yard art.
I power my mill with a White single axle road tractor. 6-71 Detroit and 10 speed roadranger. I cut the frame off behind the cab and run the driveshaft to the driver pulley with is on a shaft with 2 pillow blocks cemented in the ground. So if the truck kicked the bucket, I can just disconnect the driveshaft, drag it out the way and put another one in its place. Works out pretty good for me.
A 371 is on the small side for a mill of any size. If you use belts, a power band will work a lot better than a flat belt. To get the power you need, I think you should have a four valve head and big injectors at the least. Might get some help from a turbo, but they don't do as much as you might expect on those smaller units. You can get a little more if you run a straight exhaust, but run it high or you will lose your hearing. The best set up would be an over center clutch into a 3 to 1 reduction gearbox, then a driveshaft to the mill. There are lots of this type of units used by the Dutch in Pennsylvania. Look up Lancaster Farming. Lots of diesel shops advertise there that will have just what you need, including the experience to put it together. Remember, your Detroit needs to be running flat out to make power and be efficient.
I run a Chevy 350 with a 4 spd manual. My arbor shaft has a shear pin. The engine has a belt drive governor. Put the trans in second, set the throttle lock and it gives me 600 rpm at the blade.
(https://forestryforum.com/gallery/albums/userpics/43722/0930181734.jpg?easyrotate_cache=1538353694)
(https://forestryforum.com/gallery/albums/userpics/43722/0930181734a.jpg?easyrotate_cache=1538359472)
Any ideas? Note the flat carbide we are pointing at.
I am using an 8" flat belt to run my Belsaw M-24 because it allows me to run the engine in the opposite direction as the arbor (by putting a twist in the belt) and also allows me to locate the engine 20' away from the arbor which I had to do with the design I went with. I was wondering if I could do the same thing with a power band. Does a power band look like a flat belt but with v corrugations molded on the inside? The flat belt is the weak link in my system because of slippage but it works with enough corn syrup!
A power band is really just a bunch of v belts connected to each other. You can't run one with a twist. If you need to reverse the rotation, you have a couple of options. A Detroit can easily be reversed by replacing the camshaft and starter. Any engine can be swapped end for end if it is driving a belt pulley. If there isn't space to move the engine to the other side of the drive axis, you can usually turn the engine around in its cradle and take the power off of the other end of the crankshaft. If the balancer is such that it won't accommodate a pulley, the simplest way to deal with it is to mount a jackshaft that runs from the rear of the engine to the front. A short set of belts drives the jackshaft,another set connects the jackshaft to the mandrel of the mill. One advantage of the jackshaft system is that it can be used as a step up or down to regulate output speed.
Quote from: Haleiwa on September 30, 2018, 06:40:56 PM
A 371 is on the small side for a mill of any size. If you use belts, a power band will work a lot better than a flat belt. To get the power you need, I think you should have a four valve head and big injectors at the least. Might get some help from a turbo, but they don't do as much as you might expect on those smaller units. You can get a little more if you run a straight exhaust, but run it high or you will lose your hearing. The best set up would be an over center clutch into a 3 to 1 reduction gearbox, then a driveshaft to the mill. There are lots of this type of units used by the Dutch in Pennsylvania. Look up Lancaster Farming. Lots of diesel shops advertise there that will have just what you need, including the experience to put it together. Remember, your Detroit needs to be running flat out to make power and be efficient.
Not to many years back 3-71's where common on small commercial mills.
Quote from: mike_belben on September 30, 2018, 10:05:52 PM
(https://forestryforum.com/gallery/albums/userpics/43722/0930181734.jpg?easyrotate_cache=1538353694)
(https://forestryforum.com/gallery/albums/userpics/43722/0930181734a.jpg?easyrotate_cache=1538359472)
Any ideas? Note the flat carbide we are pointing at.
I think those are kerf cutters to allow more abuse and keep the plate cool.
Quote from: Trapper John on October 01, 2018, 02:03:16 AM
I am using an 8" flat belt to run my Belsaw M-24 because it allows me to run the engine in the opposite direction as the arbor (by putting a twist in the belt) and also allows me to locate the engine 20' away from the arbor which I had to do with the design I went with. I was wondering if I could do the same thing with a power band. Does a power band look like a flat belt but with v corrugations molded on the inside? The flat belt is the weak link in my system because of slippage but it works with enough corn syrup!
Be careful, I bent the mandrel doing that [ tightened the belt too much]
Flat belts work but they are a poor way to transmit power to the arbor especially 1 7/8" arbors. From load to no load they flap and sail and that can't help but affect the arbor and saw. Even multiple Vee belts take a set when cold and need to be run a wile to smooth out. The best lashup for a Belsaw is the tractor PTO shaft with a slip clutch especially if the "U" joints are not angled too much. Frank C.
You all have more experience with this. I'm splitting hairs but if the engine is fixed it might be worth exploring. I've found with mine I don't want to be aligned dead straight with my pto shaft and mandrel. The pto shaft seems to bounce on the U joints less if I park the tractor just an inch or two off of straight in line. Mine has shear bolts and I buy them 10 or so at a time, a slip clutch would be a better setup there.
I plan to switch over to a stationary engine with pto and clutch, there is a 12" flat belt pulley on it and then a hub and 36" tire on the mandrel to do the step down and reversal. The slip and shaft side load will be adjusted coarse by sliding the engine and then fine with tire pressure. I'm hoping all that dials in within the stiffness of the mandrel and bearings. I'm wondering if the engine is better upstream or down of the mandrel or if it matters, I'm thinking lead "distortion" there more than anything.
You didn't say what brand it is or the size. A 371 G.M. will be fine on a smaller mill but yours sounds kind of fancy with air dogs. I probably would not try to push anything much bigger than a 48 inch saw. Maybe a little more. It is a common motor on older mills. I have seen a number of responses as to the connection method. Which ever you use, you need a weak link. I prefer belts as I have had a wreck on of these and the belts worked. An exhaust extension on a Detroit is wonderful. Their sound alone will make you work. Engine position will depend on engine rotation (they were made both ways) and whether the mill is right or left handed. Regardless of all this, look at this thing and if you even start to think it needs a guard, build it. Think about the little things. Use your safety glasses, ear plugs, and hand gloves. These units can be very intimidating, as they should be. A big learning curve. My best to you and yours. Enjoy.
Quote from: mike_belben on September 30, 2018, 10:05:52 PM
(https://forestryforum.com/gallery/albums/userpics/43722/0930181734.jpg?easyrotate_cache=1538353694)
(https://forestryforum.com/gallery/albums/userpics/43722/0930181734a.jpg?easyrotate_cache=1538359472)
Any ideas? Note the flat carbide we are pointing at.
Mike I'm not positive but I think those are edger blades
smiley_thumbsup
Sorry for the hijack
Quote from: Don P on October 01, 2018, 08:43:21 PM
You all have more experience with this. I'm splitting hairs but if the engine is fixed it might be worth exploring. I've found with mine I don't want to be aligned dead straight with my pto shaft and mandrel. The pto shaft seems to bounce on the U joints less if I park the tractor just an inch or two off of straight in line. Mine has shear bolts and I buy them 10 or so at a time, a slip clutch would be a better setup there.
I plan to switch over to a stationary engine with pto and clutch, there is a 12" flat belt pulley on it and then a hub and 36" tire on the mandrel to do the step down and reversal. The slip and shaft side load will be adjusted coarse by sliding the engine and then fine with tire pressure. I'm hoping all that dials in within the stiffness of the mandrel and bearings. I'm wondering if the engine is better upstream or down of the mandrel or if it matters, I'm thinking lead "distortion" there more than anything.
That tells me that you have one or two worn bearings in the universal joints. A properly aligned u joint should have no bounce, but if there is backlash in it, you will see a bounce, which is your shaft's way of telling you that it is waiting for the right time to fly apart. The slight misalignment is simply creating tension on the driveline, which muffles the vibration. Worn splines will do the same thing, but joints are the first place to look. One other thing that will create chatter is if the yokes on either end of the shaft are oriented opposite each other, but most shafts nowadays have an asymmetry that will prevent that.
2 things; The motor is mounted on the board end of a sawmill to sorta counter act the force of the saw in the log cutting. Drive shafts with U joints are not meant to run straight or said another way the joints should work. These rules are broken all the time.
Lay the shaft on a flat table and be sure the joints are in phase.. Meaning they both lay flat.
I built a lotta driveshafts. Its news to me that they cant run straight and im kinda not buyin it. They dont like being out of phase and they dont like unequal angles.. IE one yoke straight and one at 10*.. Thatll cause acceleration at one end and none at the other, the tube will not allow the two ends to experience difference acceleration rates and will wear out every part as quick as it can to let them become independant ends.
Single cardan shafts like equal angle on each yoke. If only one is gonna be straight then youll want a double cardan at the other end.
For your own sanity its good form to build a doghouse around the Detroit. Have enough doors for ventilation and in the winter direct the warm fan wash towards you and your off barer. Good place to lock up tools peaveys and cant hooks. Frank C.
I ran a drive shaft straight for quit some and didn't have any trouble. A very experienced mechanic took the drive shaft [shafts] vibration out of my tandem axel, 2 transmission log truck. He showed me the formula and all the shafts had to be on angles. It was said that the drive shafts are never to run straight.
My shaft has acted the same for over 20 years so I'm not thinking the u joints are about to crater. I've also heard the same thing about U joints needing to work, not saying that is right or wrong but I can wrap my head around it. The tractor is old enough to draw SS so the splines are certainly not great. The way I park the tractor it is in line with the mandrel but offset slightly, which means the angles are about the same. Now when I run the bush hog I have set it up with the tail high many times when I'm backing into roses and heavy brush... the pto shaft is running at many offsets and the u joint angles are dissimilar. I've worn out u joints but nothing like flying apart on it. From what I think I'm hearing Mike, you are saying with a single u joint on each end of the pto shaft the drive and driven shafts have to be parallel to avoid excessive wear. If you want to run them at anything other than parallel, as in turning a corner somewhat, you need a double U joint at one end?
[Cliff notes. If you have 2 joints you need two equal bends. If you have one end lined up straight and one end bent, you want a double cardan at the bend. ]
What you can get away with on a 540 rpm tractor and a shaft you do not sit ontop of is a lot different than a 5000+ rpm driveshaft on say a racecar, that has components strapping it essentially under your butt, especially if it is a 2 piece shaft with carrier bearing.
Consider a single universal joint. If you have zero angle on a joint then both halves will run at exactly the same speed across the joint, like a lovejoy jaw coupler. The needle bearings wont move. As you add angle to the joint, the joint caps and needle bearings get a lot more active, and there is a fraction of a second where the slaved side of the joint is moving faster than the master that is driving it.. This is the acceleration i was describing. The more angle the more acceleration. Now to cancel this out we need another joint at the other end to have an equal angle so it is also marching to the same beat at the same time. With single cardan at each end you halve the total angle between the two joints so that the acceleration is even along the entire shaft. Phasing joints is important so that the acceleration starts and ends at the same time for both joints, they are sync'd.
When you use a double cardan shaft you have 3 joints. The solo universal has zero angle (shaft and yoke are inline) and the other end has two joints each sharing half the bend degree for the reason described above.
In automotive applications, vibration can be from out of balance tires and shafts and so forth. But if everything is truly zero balanced and there is still a bunch a shakin going on.. Its usually the driveline. New joints, tight slip yoke, good carrier bearing, zero balance on the machine.. Still shimmy? Get your magnetic angle finder out. The output and input flange faces are probably a few degrees off. Shim the rear or lower the trans and itll clear up.