Back story: Monday of this week I found a knuckle boom crane (used chassis, new crane, at the dealer) that according to engineering report the truck weighed 42.6klbs on 3 axles, 23' spread from steer to rear tandem. The weight split was 12.2klbs/30.4klbs, 42.6klbs gross. When they were doing the temporary tag Tuesday they had a weigh ticket showing 18klbs/29.5klbs and 47.6k total (yes, the total on the ticket is 120lbs more than the sum of the two axles). Wednesday, coming into TN, I was stopped on the scales. The readout showed 19.5klbs/31.2klbs, 50.7klbs gross. Obviously it's less than ideal that the truck has somehow gained 8klbs, but the main problem I see is the 19.5klb steer axle will be very hard on residential driveways, which is the main application for the truck (residential tree removal). A secondary problem is the drastic reduction in payload. Mississippi allows for 54klbs on the truck as configured. The salesman for the truck is here in town for training tomorrow and Monday. I plan on bringing the massive weight gain tomorrow and that 19.5klbs on the steer axle flat out doesn't work for the trucks intended application (the truck was specifically built for tree removal). One fix to get the axle weights under control is to add a pusher axle. The crane is rear mounted, the idea being it will commonly back onto customer's driveways vs pulling in. I don't want a rigid axle, because the whole point of the truck is to be maneuverable. Ironically adding the pusher axle will put my front axle overweight if I pick it up. I've heard of two "reverse steer" pusher axles, Watson & Chalin and Hendrickson (in the Euro market). I left a message for W&C Friday but haven't heard back from them. Does anyone have experiance/feedback on reverse steer lift axles? My understanding is they have linkage that changes the caster of the axle for self steering while backing up. Another idea is to go twin steer. I know Simard is a common name for aftermarket twin steer applications. I can only imagine the cost is "high", does anyone have feedback on the practicality of adding a second steering axle? The pusher give me 57.5klbs of gross capacity according to bridge law, but my weight will be around 52klbs... still, that will almost double my legal payload while getting my axle weights down to ~13klbs on average... far more driveway friendly, although still more than I'd like. Down the road I may look into adding a pin on tag axle to get the weights down to ~11klbs and gain a substantial amount of payload (66.5klbs gross). Since we all like pictures: Here's the side profile of the truck. The pusher would need to go where the fuel tank is currently. The boom is not in this position for transport, just to move it on the same property without having to drop the grapple saw. The felling grapple saw weighs 900lbs. Here's the truck working on our property.... the third tree I've removed with it.
And here's it dropping off a mini grapple shear (450lbs) at the shop and loading a dirt pan (2900lbs) and mower (2200lbs) onto the flatbed.
How much reach dose the boom have?
84' of hydraulic side reach at ~17' height, 1320lbs at that distance.
That is sweet
I'm assuming the knuckle all folds up in the rear area , putting most of that weight behind the tandems. Just looking at it, I would say a pusher right in front of the tandems, non steer, would be my preference, if your really trying to get down your steer axle weight. Then if your wanting to decrease more, a rear mounted tag, steerable or non. None of that will decrease the chances of point loading when crossing a curb. You're 50k and adding 2k or more with each axle you add, nothing is changing that without going to a lighter unit, unfortunately there's no free lunch. What suspension is on the truck, air ride or spring? Very few "boom" trucks go to twin steer- its simply too expensive of a carrier for initial cost, most are adding tag axles front or rear, depending on turntable and tandem locations. If you really want twin steer- I think it would be easier to find a different chassis already set up for it, as to convert yours, but anything is doable. First picture- front rig is around 48-50,000, three axle carrier, don't worry too much about driveways, sidewalks it always depends on the sidewalk and I make that clear before crossing one, I don't accept liability for them. Second rig- white and red, is just under 80,000. Twin steer (spring), tandem (walking beam), rear tag (second picture shows the tag better). Rear tag is air ride, fixed (non steer). Crane is around 44,000 on just the rear tandems without tag. If going into poor conditions, you want to release the rear tag air, and I can also remove a pin and allow the whole thing to float, otherwise you can pick your tandems up too much, making you spin out/get stuck. Third rig- white and black, is just under 100,000. twin steer, tandems, tag in front and behind tandems. Rear tag is a floating steer axle, one in front of tandems is fixed. Both air ride suspensions. Walking beam rear suspension on tandems, front steer springs. Rear tag gets raised when backing up. Front is releasable also. I added the tag axle on the red and white rig and both tags on the black and white rig. I am only allowed 20k/ axle in missouri on my oversize/weight permits. If you get over 54k gross, you will need to look at your individual state laws, you don't want to push yourself into permit only travel if you can help it, unless its only a yearly fee, and no routing. On the air tags. I prefer a fixed non steer tag, the capacity is much better and fewer moving parts. A lot of the dump trucks by me have the steerable tags and they can carry less and are less durable. I went with a steerable tag on the rear of my black and white colored rig because its so far behind the tandems, I was afraid a non steer would drag too much when cornering. It is a 20k axle with float tires on it.
This is what will be cheapest to do: The second picture is what a twin steer mack is like, but it would take big $ to switch to.
A picture of it all folded up for transport would give a better idea of where the weight is for adding axles. If its boom forward , will be different than all folded up tight on the rear. A behind the tandem tag is going to increase your steer axle load, one right in front of the tandems will decrease your tandems and the steer axle loads, how much depends on the boom location, and where you place the axle.
Not to seem unappreciative of the information, but to clarify a few points for sake of identifying my problem. I also understand it takes weight to support the boom and its weight. The issue is the truck weighs 8klbs more than engineering said it would and 3klbs more than they said it did right before I left. The physics of where to put the pusher axle isn't a question. We know what the axle weights are (fixing to go get a printed ticket from the local Cat scales), from that and measuring the axle positions I can calculate to accuracy of the weights what the axle loads will be with the axle installed, including running the numbers to calculate what the optimal load is. I can also calculate the effect of moving/adding/removing any weights to the truck, for example my thought was to make the front bumper pin on so I could easily remove it and set it on the back of the deck. To illustrate that the axle loads are the answer and not the visual representation of the truck... the front bumper weighs nearly 2klbs and the headboard has ~2klbs added to it. The pusher needs to be as far forward as the chassis will allow to reduce the load on the steer axle.... adding a tag axle will take load off the drives and shift some forward to the front axle(s). With that out of the way: On the last picture, the white and red Grove... did you add the tag axle? Do you have any idea what twin steer costs as a ballpark? $30-40k? I haven't found a reference online yet, so I'm shooting from the hip. I know adding hydraulic assist (4x4) to the front axle costs $30-40k. Do you know of any reverse steer lift axles? Running a rigid axle like on my tri axle grapple truck wouldn't be fun with it being so far from the drives, just like on the white/red Grove. Being a crane service (my assumption) vs the contractor to the customer, I think your liability for the driveway is considerably less as well as the damage to your reputation if it happens consistently (customer would blame contractor, if blame was assigned). Also, this truck will be on concrete driveways on the vast majority of its jobs; I assume your jobs are considerably more varied. Switching chassis at this point isn't something that's terribly exciting... my presumption is it would cost ~$20-30+k to move the crane to another chassis (engineering, potentially a new subframe, and the associated labor). This chassis is low miles (135k) and low to mid hours (~9.2k).
Axles are home built add ons. Both rear ones are pinned on- I can remove them if I need to for a tight jobsite. I got the axles from a local junkyard, they probably came from dump trucks. I can get some pictures of how I attached them if you want. The red and white one does not steer, the white and black one does. I would bet switching chassis would be cheaper than adding twin steer. Is the dealer going to stand that cost because it weighs more than they said, or is it on you? I've never been around a reverse steer axle, my rear steer tag on the black and white one has a pin that will drop to lock the axle from steering if you were backing up. I never use that pin, I just raise it. But you could do something like that.
The only reason I was asking how it sets stowed, is that boom position is probably the easiest way to transfer weight off of your steer axle. If it would fold up and stow behind the turntable instead of ahead, that would change a lot, but it looks like the outrigger boxes are in the way to do that. I'm assuming they added the heavy bumper and headache rack for capacity chart requirements. It also looks like the easiest place to mount a axle would be right in front of the front tandem. Looks like only a storage box and racks on each side, much easier than moving fuel tank and hydraulic tanks. I was looking at cheap and easy if its up to you, if its the dealer changing everything- tell him to get it to meet his sales specs.
I would love to see how your axles pin on, that would be very handy. I have some ideas on how to make it pin, but nothing concrete. I don't know that I Would ever actually add the removable tax axle, but the idea has crossed my mind. They did add the weight to the truck for stability. One nice thing about the truck is that it doesn't have to be level to work, which makes setup pretty easy! Also the tires stay in contact with the ground. I asked the dealer what it would cost to swap trucks, he said ~$35k. Twin steer is $50k according to him. It's true that adding the pusher in front of the drives would be easier, but to get the most weight off the front, the axle needs to be as far forward as possible. With the pusher taking 13000lbs (assuming 2klb installed weight), it would take 6400lbs off the steer and 4600lbs off the rear. From today's ticket that would put my weights at 12940lbs/13000lbs/13100lbs/13100lbs. Moving the fuel tank, tool box, and hydraulic tank will add some to the steer axle. Took this picture for you today.
Ouch I'll take some pictures of my two pin on axles, they're not fancy but they work.
First for profit job with the truck, it was a success. I talked to W&C, their reverse steer axle is what I thought it was, a steerable lift axle with some added linkage that shifts the caster to negative to self steer in reverse.... seems like exactly what I am looking for. I took some measurements from the truck to do the calculation on the axle weights. I am considering adding a pair of axles to lower the weight per axle even more as well as more legal payload while traveling.
Being a simple hillbilly ........ The first thought that came to mind is move the drive axils forward about 2 feet give or take putting more weight on the rear drivers & take some off the steering axil ? How much could that cost , 5 to 8 thousand at a truck shop ? This sounds more like a weight distribution problem with chassis & wheelbase . No need for tag axil in my opinion at 50k gross after you get proper load on the rear tandem .
Where was ballast added and what all is it? Has it been ballasted per a spec or just where they could stick the stuff? Think of it like a race car on the scale, right front too heavy? Ok let's move a chunk of weight back or over. If it's a space issue I've go some tungsten but it's very cost prohibitive! Although you are correct as far is payload, there's not much room weight wise for that. It's always a trade off isn't it? Lol. Nice looking truck for sure. With some big boxes and a monster welder it would me a me a heck of a service truck! Junkyard
So there's only 15k on each rear axle? how about scooting them both forward a foot? Seems like you don't have a lot of cargo capacity on the flat deck over the road. Need a fancy axle shifter like a landall to mess with the guys at the scales
The ballast is added for stability. For example, the front bumper and headache rack weigh ~4250lbs combined. Moving the drives forward also has the benefit of decreasing the turning radius. Still, for driveways I would like to add an axle to lower the axle loadings. If I moved the drives forward 17.5", they would have approximately 34klbs on them, 16,140lbs on the steer. If I moved the drives forward 14.8", all axles would have ~16,713lbs on them. If I didn't move the drives, 4 axles with an even weight distribution (12,935lbs), the pusher would need to be installed 86" behind the steer axle. The front of the fuel tank is at 83", the back of the outrigger box is at 72" so it will have to be a bit further back than that. I'll run some more scenario and see what I come up with. Moving the drives forward, adding a tag and pusher sounds like the best of every world... better weight distribution, better turning, no compromise in stability, better payload on the deck, better ability to carry a front heavy tag trailer.... just costly.
Yeah lumberjack ... That looks like a nice rig & knuckle boom set up perfect for your work . I sure like the saw attachment on it . If you like the truck & plan on keeping it I would not hesitate moving tandems forward to solve the problem . Nothing worse than a truck that's to heavy on the steering axil . They drive like a monkey riding a football on the road at speed and get stuck to easy when off road Time to drill some new hole's in the frame & shorten the driveline Mate ! Move the drives about 2 foot forward and you will notice a huge difference in that truck . If ya want to get wild move the drive axils 4 foot forward & install the tag axil on the rear . That would sure allow you to walk around job sites with most of the weight on the rear drivers and tag axil down for on the road for stability at speed .
Pictures of my 70 ton's tag. It's a steer axle- probably a 20k, its pretty big. I made everything else. You can see the brake pod that drops a pin in the steering arm to lock the axle straight. I never use it, I just pick the axle up (its air up air down). I can drop the rear jack and remove the center bottom pin, allowing the axle to float up and down on the upper two pins, works good going offroad and when raising the front of the crane way up, to avoid overloading it or picking the drives off the ground. I can also put all three jacks down and leave it set in a parking lot, if I have to get close to something. I wouldn't do that on rough ground, you would have a hard time getting hooked back up, but I rarely drop it.
The air up, air down, and lock pin are all controlled by electric/air switches you can see at the rear, and a air regulator set for pressure on the lift bag. I just used a smaller trailer plug connection for my controls, and its own wire, and a regular trailer plug for the lights, then the regular air lines, like it was a trailer (makes it easy to unhook). I used a steer axle on this crane, because with the large outrigger boxes on it, it sets a long way behind the drives.
If you start adding axles and/or moving stuff around, do you have to go through a whole re engineering of the mounting system? It's a manbasket capable rig- they usually have to engineer where the weight is exactly and what it weighs, so just moving the axles forward would be possible, but it changes your counterweight position. Would you have to pay for that to be done? I would see what costs are involved with that also. I'd be a little concerned that the engineering report is so far off from what the rig actually weighs. I wonder if they used this actual mounting (your rig), or if they just gave you the manufacturer's minimum recommendations for the crane (or some similar mounting they did in the past). This is what national gives you when mounting (page 3 of the pdf)- they say at the bottom to perform a actual test as mounted- and I'm sure there's a test procedure. If I was in the manbasket, I'd want to know for sure. With your front way heavier than the specs, all that weight is beyond the front outrigger boxes, making it act like a load when the boom is out over the front, it makes great counterweight when your out over the rear, but that's all supposed to be in the drawings, and in a new rig I would want it to be right. I should have the pictures of the non steer tag later this week.
I did make an error in my calculations, used the front axle for my measurements but the front bumper for my calculations... I guess having a 2 month old will do that! I assume taking the axle off and on is not exactly a good time getting the pins in and out? Moving the drives forward would move the CoG forward as well. That would mean the weight on the front could be reduced, if I was so inclined. The two main concerns I have over moving the axles forward are stability reaching over the side (torsional rigidity of the subfram) and point loading on the frame. I don't believe either will be a major concern. Tipping over the front of of fairly low concern with a rear mount, over the rear is the bigger concern. The stability test for the truck is fairly simple, pick up a weight, push it all the way out, and rotate it 360* making note of how high the opposing tires/outriggers lift off the ground. As opposed to a stick boom, knuckle booms are quite flexible both in terms of usability and setup, including the outriggers. The outriggers can be set up anywhere in their span, vs short, mid, or full span. Also, the tires of the truck stay on the ground, even if you're not level. Being particularly level isn't required. You do want to do most of your long reaching inline with the slope.
It's not as bad as you think it would be- with the three jacks on it you can tip it every which way, but I only drop it on pavement. I wouldn't try to drop it on a uneven ditch. It helps to have someone with you to hook back up.
Thanks! Sitting at her 2 month checkup now. It does have a 100% 360* chart. The specs for lift on the passenger side outriggers (lifting over the driver's side) is 12" on the rear and 6" on the front! So far I haven't seen more than a quarter of that. I plan on doing some testing to see how much safety factor the truck has for stability. That testing will also let me calculate the reduction in capacity with the truck being out of level. Keeping the truck inline with the slope should keep the reductions to capacity very minimal. At some point the more likely issue is the truck staying on the slope traction wise between the rears and the ground. Chocking the tires and/or using a winch is an option for that. Stability wise you can also add weight to the deck. A 10* slope only moves the center of gravity 1.5% back... negligible. That's a bit over simplified, but yeah.
So just so I'm clear- the chart/capacity on the label on the rig is 100% of capacity? Cranes on outrigger's charts are 85% capactity, on rubber is 75% and manbasket work require's 50% of chart. I would think that they have some derate measure for if you're up in the manbasket? Does the rig have a pressure shut off on the boom cylinder that's set for capacity (a lot of small boom trucks are that way- so much pressure on the main boom cylinder and it will just bypass)? or are you all on your own and it will pick until it tips? (I'm just curious how its set up, I like to learn ) Then again, we're probably overthinking this whole thing, just add a axle in front of the tandems and one behind, do a few test picks to make sure you haven't affected stability of the crane, and go make $. I would probably just add one close to the tandems to save moving as few tanks as possible, and keep checking your weights, then add the one behind last. I can see where getting the axle loads down would really help in residential yards, and crossing sidewalks. Moving the axles ahead would lighten you up front, but won't reduce the overall ground pressure like some extra axles would. I could see that being a great rig for taking down dead trees, no danger of being up in the tree and trying to rig it up and fall it, and much less need for extra men also. Also- I rarely unhook the tag axle on either crane. 50% I never touch it. 48% I pull the bottom pin so the axle will float (off road and steep terrain). The other 2% I unhook it, for either getting really close to something, or if I'm going to need at the big tow lugs on the rear of the crane carrier to hook up to a excavator to pull me in or out of a jobsite.
Oh Man ! I know how that go's . I heard they eventually turn into teenagers ? Hang tough lumberjack
That's cool , sounds like you can grab a load and good for the full 360 degree swing .
My oldest is a senior in high school, off to college next year - and I have no idea where the time went. If I mention that we are probably closer to grandkids, than when we had our own kids, my wife gives me odd looks. I don't feel any different than when I was 20, but my hair isn't quite the same color as it used to be either . Congrats on the new girl, enjoy it, it goes fast.
Are we still talking about the knuckle boom rig or a old school 750 Holmes wrecker ?
Boy aint that the truth Crane Op ! I'm in the same boat . At little league ball games I look at the parents & some of them look like they just got out of high school . I get mistaken all the time for my boy's " Papaw " . LOL ! Dealing with equipment ,trucks & cranes is allot easier than raising kids
The more I've read this and thought about it I could see where a couple axles would be beneficial. Any more news on the reverse steerable axle? I may have missed that. We've been so busy I can't goof off, oops I mean stay caught up on here . Congrats on the kiddo. My oldest turns 18 Thursday. She has her moments! Youngest is 2-1/2. Three between them. Pray for me! Lol. TD before I had a hydraulic crane on a truck I had a Brockway with a 750 Holmes, extendable booms. Had a drag winch with about a half mile of cable on it. Came from Maine I think it was. When they took a field trip and needed winched out they must have really gone into the bush!! It was easy to run out the back, lift until the steer tire was off the ground, then go a little more! Off the side I'd sometimes swing the leg out, set it a foot or so off the ground and quit when it touched. Kind of like an indicator. I can't believe that rusty old frame never split on me. It was even the super deluxe body Off topic I know! Oh btw, iron is waaaay easier! Junkyard
The chart has weights at various points, but the crane doesn't have a LMI. It has pressure transducers on the various boom cylinders (but not the extension cylinders) and the readout on the remote is in percentages. The computer stops you when you hit 100%, however there's a high pressure, low speed setting that gives you a 10% boost by slowing the boom down. This chart doesn't show the single manual pull out that adds 6'. We have a 15 year old and a soon to be 12 year old also! The baby was supposed to be born on 3/13, the boy was born on 3/12, and the girl 3/29... the baby (Carly) decided to come on 1/19 which worked out greatly for the best. Yes sir, on some setups the crane has derated portions of its rotation and it tracks the z axis/rotation of the crane to adjust the percentages when in those areas. My crane is 100% for 360, so it doesn't keep track of the rotational position. Thanks! I could be a grandfather in another 10 years I suppose, that would put the oldest at 25. The reverse steerable axle works like I thought and is rated for 13200lbs and a single 22.5 or 24.5 tire/wheel. The crane dealer is waiting for me to give them the part number to order the axle. I am meeting with my mechanic in the morning to see about moving the drive axles up. I can move them up to 61" forward by moving the step ladder holder and the tool box. It still crosses my mind to move the drives forward and add a tag and pusher to the truck... we'll see, my money reserves are fairly depleted at the moment! Here's some pictures playing around this afternoon, showing the truck to my aunt. Good for roughly 800lbs with the manual pulled out... 1300lbs if I give up that 6'.
That will be interesting to hear what the mechanic has to say about it ? Just looking around Truck Paper found a few trucks with rear mount knuckle cranes similar to yours for ideas ? http://www.truckpaper.com/listings/trucks/for-sale/18462975/2017-freightliner-114sd http://www.truckpaper.com/listings/trucks/for-sale/4818461/2005-mack-dmm6856s http://www.truckpaper.com/listings/trucks/for-sale/17279585/2017-western-star-4700sb
Is that a common way of doing tree work in your area? I've never seen this method before! Here they use either a bucket truck or climb, occasionally a traditional crane to hoist a large tree from a spot with limited access. It sure is an interesting idea.
I was talking to him about pricing/feasability of moving the axles, adding the tag or pusher (or both), and plumbing for trailer brakes. Shooting from the hip, it's looking like a 2 week job, probably $10k plus the lift axle. 2 weeks meaning 80 hours at $85/hr... I didn't get a price on doing the steps separately. Moving the axles doesn't seem like that big of a job, but maybe it is. Thanks for pulling up those trucks. It's funny, all 3 have the drives forward and a tag axle at the back.
No, there are less than 40 trucks in the US doing tree work this way... it's a very new idea in North America, more common in Europe.
I shot a video of this job, didn't take a before picture, but here's the last piece of the tree being removed from somewhat of a tight spot!
Moving a set of drives is a job... Look up in between the axles, there is normally a huge crossmember midway between the axles that may have a gazillion bolts or huck rivets to remove and redrill holes to move it with the axles.
Removing bolts/hucks doesn't seem like that big of a job on a clean truck. A healthy impact should zip them right out eh? If not, a plasma will... Redialing the holes doesn't seem like a big deal with a mag drill. I'm not saying I could do it in an afternoon, but aside from waiting on parts, it seems like (to my never have done it self, just looking at what's there), 2 people should be able to knock it out in a couple days.
Hmm, Z out 24 inches of frame in front of the axles and install it behind the axles!
Nice work on the " deck tree " removal job lumberjack ! You even got to crawl under for the last cut .
Pictures of my other removable axle. Air down spring up. Usually have my spreader bars mounted in the brackets on the top.
Your mechanic is probably not far off on his estimate . Like RZucker mentioned it aint a short task even with proper tools & equipment . Allot to deal with under the truck other then drillin & boltin . Air lines / valves , driveline , moving toolbox & accessories ? 80 hours for a job like that seems reasonable to me . You know ...... There is also merit to leaving it be what it is . The Mack is a little heavy on the front & light on the rears . From the work photos it seems to be performing well & looks good in operation .
From my experience, trying to match up bolt holes from outside the frame is a slow process if you want it done right, most mag drills don't fit inside the rail. An 80 hour quote... Pretty good deal if they stick to it.
If it is a bare frame moving the axles is about like you describe, working underneath the bed I would want a good helper that knows a huck bolt when he sees one. 80 man hours is not unreasonable to me. Nothing hard work and money won't fix!
Thanks! Here's the video from that job: Thanks for the pictures! What are the capacities of the two pin on axles? For context, he also parking lot ballparked ~60-80 hours to reframe my grapple truck (should it ever need it). Seems like that would be far more work than moving the axles forward. The truck will be getting more axle(s) under it... the idea about moving the drives forward seems like a win, the only down side is the cost, and I can make money so that's a wash. Granted I've never done it, but my theory was to use transfer punches, hand (or mag if it fits) inside out, then mag drill from the outside using the pilots to locate the holes. On that note... how precise are the holes in the frame in terms of tolerance on diameter? I think I remember reading something about reaming the holes, but that seems powerfully precise for what I anticipate it actually needing.
The red pin on axle is a modified semi trailer axle, if you had duals on it, it would handle 20k. I only have to put about 10k on it to get legal, so I just run singles on it. Less rubber to scrub while turning. The black one is a old 20k steer axle, I've only got 385's for rubber on it so I think they would be good for 18k, I actually only need about 10k on it also to be legal. The reason I oversized the axles so much is that in sharp dips and areas, you can really point load a rear axle very quickly. The black crane is around 60k on its drives (without the 2 extra axles), a too light axle back there is a recipe for disaster, or at least bent up iron. I got both axles from a local truck junkyard, they had both been under dump trucks as extra axles, they usually have a row of 8-10 of them, and each time I just drive up and pick out something I think will work. I think I gave $500 for each axle, then built the rest of the frame from frame rail from the junkyard, and built the pins and brackets, etc. for the rest. "When in doubt, build it stout!"
Yeah RZ , we would drill mostly from the outside of the frame with the mag drill . I've found one of the best tools for indexing multiple holes on a project is .... Cardboard . Cut it accordingly to shape and clamp it snug to the surface . Then go along with a ball peen hammer knocking out all the holes . Makes a pretty good template for marking out the new hole locations .
Thought about that while I was wedged up under a customers old R model Mack yesterday . Installed all drive line seals on the rear axils . Next round the 5th wheel plate is coming off ! I'm gettin to old to be crawling around under suspensions & banging my head for a simple task . Not to mention washed the pants & shirt 3 times and I still smell like a Mack . LOL!
That's pretty cool lumberjack ! Your better on the remote control then I am ! What few RC planes I had in the past it usually ended bad I would have to set in the seat position to operate your rig
Bulldog lift his leg on you?
Yes, I do use transfer punches and drill a 3/16" pilot hole from the inside where possible. But in the "K" member between the axles there are a lot of holes you cant hit that way. And yes, I use frame reamers. personally I think its easier than fighting the mag drill most of the time, 3/16" pilot hole, drill out with a 3/8" bit, then a 3/8" to 1/2" reamer, then a 1/2" to 5/8" reamer. Mag drill is great if you don't have a bunch of suspension brackets or existing bolt heads where the shoe needs to go.
This is the type of reamer RZ is talking about, a Car Reamer. I haven't used a mag drill for years I start with a 1/4 pilot drill and 3/8 and on up with reamers. Truck Shop
He sure did RZ rite after he took a dump . What a mess .
So are the bolts in shear and require a precise diameter or are they used conventionally and derive the strength of the joint through clamping loads/friction? Trying to understand why reaming is so prevelant vs twist drills. Also... on a camel back suspension, how do you align the axles, or do you just align the front to the rears?
If your moving the rear tandems forward or aft measure off an old existing bolt hole along the frame that held the Mack trunnion sub frame to index the new hole locations . Fancy way of sayin measure off the old bolt holes on each side . Good lord power wash it first if it looked anything like the last Mack I worked on ! Lumberjack's Mack rig looks pretty neat & clean .
Car Reamers will cut more holes at a faster speed using lots of [cutting oil} than drills. Plus the hole is smoother than drilling and less prone for a crack to start. A 1/2" reamer will fly right through hard *** frame rail. Truck Shop
Judging from what td's using for his cardboard on his template- he doesn't need the bulldog to do it. and no- I don't think incontinence is funny- I just think rzuker's post and td's picture made me smile so I thought I'd share . I don't want to offend anyone- if this bothers someone please delete, but I try to laugh at life's little foibles and troubles. My grandpa said getting old isn't for sissies.
Back on topic though- I've never seen the reamers you guys are using, so I learned something, thanks for posting those. One more item for the toolkit.
Lumberjack you're on to something with your method. Take a tree down with no climbers and only one guy running a remote control.. With the speed, efficiency and lower WC rates since you don't have a climber, buy a grapple truck with a huge body to haul away the debris and rock and roll.
Haha I would steam clean it if I was working on it. I have a couple small hydraulic leaks that have made a minor mess. I knew you'd measure off the old holes, I didn't know if there was adjusters built into the design or if it was just where you bolt it. Good point on the stress risers! Good idea!
Yes , just measure off the old bolt holes . It will be OK !
Yep, I run my reamers with a huge old Black and Decker or an equally old Milwaukee 1/2" drill motor, a good grip on both handles is all it takes. For the lube I use Ridgid thread cutting oil. Kar products had a foaming reamer oil that worked well too. I just haven't seen the Kar guy for a while.
Got this from the engineering today. I asked if I could put the tag axle as far back as possible and put a 5th axle in front of the tandems, it shouldn't be a problem. 17" farther back gets me an extra 1klbs on bridge law, the ICC bar may have to be moved... it'll be close with the tires turned. Perhaps this chart will make better sense to someone other than me. I can't understand why we would put a tag to lower max axle weights and end up with a steer axle only 1100lbs lighter with the tag axle down, hence the 5th axle being a pusher. Couple pictures from today:
The tag axle being that far from the front I'm surprised it removes any steer axle weight at all. If I had to do one or the other I'd do a pusher first to lighten the steer up. I had a heavy haul truck with a tag and with my 5th wheel in the right spot I could air the tag up and actually PUT weight on the steer. Drives acted like a fulcrum I guess you could say. A steerable pusher and tag would be ideal in my opinion. Gentle axle loads, good maneuverability and payload as well. Junkyard
The tag axle puts weight on the steer because as you say the drives are the fulcrum. The drawing moves the drives 54" forward, which takes 4500lbs off the steer. The weight of the raised tag takes the other 600lbs off. Putting the tag axle down takes weight off the drives and puts it back on the steer. My theory is move the drives forward and install two axles at the same time. While we're at it, install the plumbing for an air braked trailer. It's just money, right? If I can get the tag axle 17" farther back and install the 5th axle, I should have ~11klbs of bridgeable payload.
Sounds like a reasonable course of action to me. It's a slick truck for what you're doing. I like new ways to do old things! Junkyard
Absolutely ! Good point Junkyard about the rear mount tag axil acting as a fulcrum . I like that setup moving the tandems forward & installing a rear tag to balance out the load on the road . Keep in mind you can " feather " & adjust air pressure accordingly as need be . Might only take 45 psi on the rear tag to equalize out the axil weights . Just have to experiment with it to find the " sweet spot " . Then when off road you can dump the tag air putting more weight on the drive axils to gain traction if need be . The original issue was a heavy steering axil & light rear axils , Correct ? Only way I know to solve it is either remove counterweight built in to the front bumper & headboard ??? Or move the rear tandems forward to help offset it ???
I'll just throw this out there for you also, lumberjack. I find a very important figure is: how far the rear (tag) axle comes off the ground, when unloaded (air up). I quite often pull my lower pin on my rear tag, so the axle can fully ride up, for example when coming off a road up a steep driveway. If that tag axle hits the ground in that situation (without enough clearance), you can pick your drives off the ground and be spun out, point loaded between your front (steer), and the rear tag axle. The further the tag is from the drives, the higher it has to come off the ground. Smaller tires on the tag would help. Making it a pin on behind the crane would be more helpful, but remove the possibility of a trailer (even if it doesn't unpin like mine, you would have more room for the tires to come up when raised without the crane above it). Maybe you could extend the frame behind the crane enough for the tag tires to come up behind the crane, and have the frame extension there also for the trailer hitch, also gaining you length for bridge. Maybe not moving the drives quite so far ahead then, and leaving room for the pusher? You only want to move those drives once, and then only if you have to, so those paper calculations are way easier to do than moving axles around. I was just a little concerned when looking at the drawing, at how much rise you would get from a tag placed under the crane, vs behind the crane. The crane above really limits how high the tag can raise up. Without my bottom pin being removed on my tag, as far back as my rear tag's sit on both my larger cranes, I know I could get in trouble in a hurry. I can hear in the cab when my rear tag hits the ground, in the up position and rides up with the pin pulled, and its quite often on rough terrain. I do like the idea of moving the drives ahead, I think the nicest part of that will be improved turning radius. Can they run a calculation for you on where you would be with just a pusher ahead of the tandems, but leaving the tandems where they are? and see what that does to your front axle loads. I also think pusher first and then tag will give you the most gain on your steer weight issue. I did own a crane like that once- single steer, pusher, tandems,(no tag) and with just adjusting air, pull weight on and off the steer. I don't think I ever saw what rear suspension you have on the truck, if it is a camelback spring or spring over walking beam, the air axles, as tag and pusher will make a huge difference in how it rides, taking a lot of bounce out of it. I can really notice on my truck cranes if I don't have them aired up. (both cranes are simple walking beams rear- no springs).
The truck has a camelback spring rear suspension. I can run the calculations putting/moving axles wherever. The thought of an even shorter turning radius is inviting; the thought of being stuck on the steer and tag doesn't sound awesome and it seems like a good way to damage the tag axle. I could fairly easily remove the tires from the tag axle for increased ground clearance, but I would still be giving up a considerable amount of departure angle moving the drives forward. Moving the drives forward and adding a pusher requires the same relocating that adding two pushers entails. Installing two axles is cheaper than moving the drives and installing two axles. Adding a tag would allow me to stretch my overall wheelbase to 25', picking up 1klbs of legal payload. Weight added in front of the rear outriggers adds to stability reaching over the rear. Adding two pushers or a pusher and a tag could make the front bumper weight decrease by 1400-1600lbs. Possible consensuses: Leave Drives as is, install two pushers. Benefits: Cheaper than moving the drive axles. Substantially less down time. Better departure angle. Better ride. Move drives forward, install pusher and tag. Like Crane Operator said, maybe move the drives forward ~31" and set the tag 48" behind them and a pusher in front by the outrigger box. That will reduce the load the tag shifts to the steer (and pusher), preserve some departure angle, and increase the bridge to 24.5' (round up to 25'). Benefits: Reduced turning radius. Better break-over angle. 1klbs more bridgeable gross weight. Potentially better control of weight transfer with the pusher/tag. Install one pusher, decide what to do later. Benefits: Least amount of downtime. Cheapest Doesn't change the ability to do either other option... the front pusher is as far forward as practical in both of the above scenarios. May "get me by" for quite some time, possibly even longer. Can drop 900lb of front bumper weight, if I wanted.
Assuming 4500lb for the drives, lift axles having an installed weight of 1600lb, and the front bumper weighs 1900lb. Installing two pushers, one at the fuel tank and one 4' in front of the drives, I would need 434lb at the front bumper. Installing one tag 17" back from the current drives, moving the drives 31" forward, and installing a pusher at the fuel tank, I would need 554lbs at the front bumper. If the drives weigh 5klbs the weight drops to 512lb. If the lift axles weigh 1800lb installed, the numbers drop to 251lb and 391lb respectively. If I wanted to put the weight on the headboard vs the front bumper, the required weight increases by 36%.
Update, I'm still waiting on Watson & Chalin to supply the part numbers for us to order the axle. It looks like I'll have to yank some chains to get them to generate the numbers... the hard work (technical) is already done! Here's two of nine trees I took out Thursday with the truck. The driveway at the second tree was in bad shape, so I wasn't worried about cracking it.
That's one fantastic tool! a little nintendo and a little chainsaw work.
Really cool video lumberjack. I'd love to have one just big enough to trim back the trees along the creeks and fence rows. Would save a me a lot time on a pole saw.
16 ton excavator works great for 'trimming' tree lines around fields for us
Another video using the ~46 yard dump trailer I bought to go behind the crane. 15klb air brake axles, twin telescoping cylinders for the dump hoist.
Looks like it's working pretty slick.
I forgot to add, after 2.5 months, W&C finally got the part number for the reverse steer axle!