Stationary Gantry to Lift Wood for Splitting

Your trees are really 4-5 ft in diameter and only 18" high? What planet is that?

I have no idea the density of this wood, or how well it approximates a circle/cylinder of wood. Sounds like a mess to me just wanting a place to snow.

I think he said, " Chunks of tree's ". I am guessing that a Chunk is 4-5 ft. in diameter & 18" long.

A 5-foot diameter x 18" long cylinder has a volume of about 30 cubic feet. I'm not sure what kind of wood it is but let's assume, say, 45 pounds per cubic foot (typical for red oak). A section that size would weigh about 1325 pounds; more for some kinds of wood. What kind of wood is it? I would at least triple for the crane capacity. Say 5000 lbs, minimum? When it comes to I-beams carrying point loads, the bigger the better. You also want to make sure the flange can bear the weigh without buckling.

My advice is to find a commercial unit with similar (or greater) load capacity and base it on that. An established design provides reasonable assurance that the problem has been considered, analysed, and that the appropriate safety margins have been considered. You can also bet the company's CYA legal dept has looked it over too and given their blessing.

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What trees do you have that are 5' in diameter.?...that would be old growth, and worth a fortune in lumber....why would you be splitting it?

http://www.northerntool.com/shop/tools/product_200651937_200651937

Key Specs

..." a beam with a designation of W8 X 10 and Nominal size of 8 X 4 can take an allowable load of anywhere between 6,900 and 15,600 pounds, depending on the span of the beam."...

http://www.engineeringtoolbox.com/w-steel-beam-uniform-load-d_1722.html

https://www.reference.com/home-garden/determine-allowable-load-beam-be7d20682d2e50a3?qo=contentSimilarQuestions

Ash trees are common in Wisconsin. They can grow to that diameter and larger. I think the record is 11 feet (3.5 m)

uunfortunately, they end to split, and ash is so straight grain the crack keeps going.

ive seen pine like that also. It was in a park in wisconsin.

There are bald-cypress trees here whose trunks get pretty big though the trees themselves aren't especially tall. There's one in Utopia, TX I saw when we visited once. It's about 860 years old they said:

Cypress is nice wood. It doesn't rot like most woods. We had an 1879 Eastlake Victorian near Houston whose siding was made of cypress. No rot anywhere, though I did find a bullet lodged in the siding when I was painting the house. It had been there so long it had oxidised.

Ash is lightweight and hard wood....used in guitar bodies...Cypress is good for closets and chests...Both I would think rather expensive firewood....I would sell the wood and buy coal....haha

https://hardwoodstore.com/lumber-prices

http://www.duluthnewstribune.com/classifieds/firewoodcoal

1 cord = 1536 board feet

and baseball bats.

Back in the early 80's we were logging near a bluff, stand of beautiful maple. With some ash. The skidding trail going down the bluff was spectacular.

as I was returning, I saw my dad cutting about a 30"+ diameter tree closer to 36", no limbs for 20', it was great, and I though, nice log and I stopped and watched so I wouldn't get in the way. And he was about halfway through and the tree, 'popped' and half the tree jumped sideways and fell. While half the tree kept standing. A split a good 25' feet up.

my mouth dropped, I could see my dad still looking up for limbs that still may drop. I came up to him and said wth, and dad said 'what?' I just said I saw that, unbelievable.

he just said, yep, must have been a sight.

We made wagon stringers, as well as eveners and poles for our team of Belgians out of ash.

Damn. I've cut down a few trees but I've never had a tree do that.

When we dropped it, the split was so clean, we could have put it on the sawmill and to square it up, the variance would have been less than an inch of slab. We ended up cutting it for firewood.

im just glad no one was hurt.

Wow, what kind of trees do you have that are 4-5 feet diameter. Hell of a bar on your chainsaw.

For a splitter, I'd avoid w-beam unless you plan on reinforce them, we made one and the problem we had was that the w-beam twist. Once we reinforced it, it was good. Consider maybe using tube, (you can use the ID of the tube for oil reservoir.)

so as a beam for a jib, that may also twist a bit.

or if you have a skidloader, think about fitting your splitter and make one that mounts on your skid steer then just nibble away at the block. Their should be something on you tube.

back to your jib crane, what weight do you have, I'll run some calls for you, but I wouldn't recommend size. That would be for you to decide.

I don't think the wood would be more than 600lbs the average is around 300 to 400 lbs I've got a log splitter that can handle that size but getting to old to man handle them into place when vertical, most of the trees I get are from the city when they have to cut down storm damaged trees

A chunk of balsa wood having the largest dimensions you gave (5' dia x 18" long) would weigh nearly 300 pounds. Basswood, only about twice as dense as balsa, would weigh 600. Are you quite sure about the maximum weight, given the max dimensions you cited earlier?

the largest chunks we've had were in the 4 to 5 foot diameter the average is 3 feet all at 18" in length , all types of species native to Wisconsin these are hauled in by cities dump trucks when they have to cut down trees ( we take free wood from where we can) So my question is what is the maximum weight a 10' long I-beam either w6x9 or w6x12 support before structural failure? this will be concreted in place or but another way what size I-beam will support at least 2000 lbs without failure

When designing a crane, you design for worst-case, not average. It doesn't matter what the average is because that's not what's going to break it.

Sizing an I-beam for a gantry crane is more complicated than you may think. Not only do have to worry about static loads, but the stresses on the beam when the load is moving or swinging. What if it twists under a swinging load and then buckles. You have to worry about that, too. Moreover you don't design it using whatever you happen have on hand, you design it with whatever beam size the maximum load demands - and then some.

I'm not going to tell you which beam to use because, quite frankly, I don't want to read about you in the obituaries. Like I said before, model your crane after a commercial unit. Look up some units that are close to what you need and see what they use and how they do it. Fair enough?

I understand all the other variables you mention, the structure that will hold the I-beam will be constructed of 4" pipe 1/4" wall thickness four of them with frame work to support a roof as to using whatever is lying around I will buy whats right so if I need a I-beam that will support 6000 lbs i'm fine with that I just don't want to buy something that's rated for 12,000 lbs if its not needed

I understand. When in doubt, best to err on the safe side.

Maybe something like this, but set in concrete....supporting the beam from the top and the weight from the bottom is inherently stable....

http://www.wallacecranes.com/tri_round_inspect_w.pdf

Hargorfreight has a 1,000 lb gantry for $730.00

I had design two for my shop, when I had to move a platform for a customer, but they were rated at 15,000 lbs and had 12" castors.

I mean a 2,000 lb capacity

Nice...adjustable height too....price is right....

I've actually been watching that. If only I had room. That and a 2 post vehicle lift. But, I'm looking at a domestic brand

It is a little narrow at 93 in....the average car is about 6.5' in width, that's only about a ft total clearance....Maybe Big Red would be better for $200...

I don't have my computer home, (im on my iPad) I'll run some numbers for you to decide, but I'd used your maximum weight plus a safety factor.

are you planing as a cantilever (jib) or a two post.

Btw, what part of wisconsin?

actually 4 post want to be able to put a roof on it to work out of the sun and or rain

I'll connect all post which will be 4" dia. pipe with a wall thickness of 1/4" in 10' length 2' of each will be set in concrete

Basswood quality for firewood is terrible, but having softer ribs are perfect for carving.

Yes there are good and bad wood for burning, but it all gives out btu's and since I've heated my house for the last 10 year with free wood I can't complain, its just those 10 years have been hard and with some medical issues have to build something to make it easier to handle the larger pieces

Yeah, I mentioned basswood mainly for comparison. It's not really a type of tree you'd commonly find in Wisconsin as it tends to grow mainly up north in the eastern half of the U.S.

In our area we have a pretty good variety of species, northeast wisconsin (peninsula)

basswood being softer grain, they use it for carving duck decoys... (More so for decorations)

my uncle used basswood when he made model ships for naval contracts, research vessels and the like.

You're probably on the western edge of its range.

I can see how it might make a nice carving wood. Personally I've used it very little and only for model work, having bought sheets of it at the hobby shop for different projects.

We have property in northwest Wisconsin in Rusk county that we frequently cut firewood for home & the cabin. It is a mix mostly of maple, ash, and red oak but we do have some basswood. We have more basswood than we really prefer as it creates too much leaf litter with those huge leaves to rake around the cabin and roads.

We never really consider burning basswood only because we have so much other better wood to cut. We get more btu’s for our effort with the hardwoods. Most of our trees only get to 20” to 24” diameter but a few oaks will get 30” to 40” in diameter if left alone. We don't seem to get any trees 4 to 5 feet in diameter. Seems most succumb to either wind or eventually the Forest Crop program with the state gets them.

Here’s the more interesting part.

I never thought there was too much value to basswood trees except for carving until I saw a demonstration by local Native American Indians who used strips of basswood bark to sew the edges of birch bark baskets with. They pull vertical strips off I think the younger basswood trees and soak it for a few weeks that soften it and allow them to work it and delaminate it into thin flexible tough strips suitable for their use. Once it dries it will last a very long time and then can be re-soaked to soften again and used.

I always learn stuff by watching and then asking questions about how others do things I’ve never seen.

One reason I like this forum is I always learn stuff here also. Thanks to all!

Redneck engineering....

It worked. This time, anyway. At least the fool didn't stand under it.

I'm guessing the big chunks are ash. You've a couple of species of ash tree there in Wisconsin; black ash being the most common, followed by green ash and white ash. You said that these are trees that were brought down by storms? So we can probably assume the wood is still 'green' at the time the city brings them to you?

'Green' black-ash has a density of about 52 lbs/cubic foot and so a chunk having the max dimensions you gave (5' dia x 18" thick) would weigh about 1550-1600 pounds. 'Green' green-ash is only slightly more dense but within that range, white-ash somewhat less.

You've hickory there too which is about 20% denser than ash, but the trees never get that big around.

I'd say your worst-case load is 1600 pounds or thereabouts.

You need one of these...on my wish list. I rent one every year.

I think this ramp approach is the safest and easiest to fabricate. It would need to be heavier than the machine pictured for 4' dia. pieces. And large tires are a MUST if your splitter is portable.

I see a winch mounted on the non-ramp side of the splitter and a chain welded to the splitter so that it would go under the tree then be hooked to the winch cable so that when you take up the cable the log rolls un the ramp into position.

That eliminates the overhead danger if something fails.

Personally, I'd never be splitting wood in the rain anyway. Too many slippery things aren't good.

He should do what my dad did,... makes dam sure he had raised enough boys to do the work for him.... lol

I didn't find a W6x9 in my CISC but there is a W6x12. Safety is the key,,, what factor of safety do you want? When I design anything such as a gantry or monorail, I always err on the very safe side as there could be a human life involved.

To answer your simplest question - at least for the W6x12 (not to be confused with an I beam or "S" section) - and only doing the basic calculation for a "simply supported beam" with 10 foot span - using a FOS of 5:1, a single point concentrated load at the center of the span your maximum allowable load would be 1262 lbs. This does not allow for any torsional load on the beam at all. You will also have to check your columns as you did not say what you were going to use. And of course the connections between your columns and beam will have to be designed, not to mention what the gantry will ride on, or if it stationary what it's foundation will be.

I am sure you can find the formulae for the steel parts on line somewhere to check everything. Good starting point, at least for me of the old school, would be American Institute of Steel Construction (AISC). I haven't done serious structural for a long time, but I am sure that they are probably still the go to institution in the U.S..

Of course if you want a design done, the best way to do up your little gantry would be to hire a certified engineer to do the design (he/she will, or at least should, ask for a lot more information than you have supplied). Better yet, purchase one off the shelf that meets your requirements as suggested by others in this thread. Probably your best bet would be to buy one - the engineering has already been done and you won't have to pay for it again - the certified engineer will be more than the cost of buying a unit "off the shelf".

Better safe than sorry.

I used a W6x12 I don't know where you got the W9x10 from?

I used 4000 lbs load centered, I didn't use any shock loads,

you didn't respond what type of frame you planned on using, a cantilevered jib or 2 post. I used a 2 post support,

Graphically, is below

Now there are a number of deflection rules you can use.what I use is a rule of thumb for deflection is

Length/240

or

Length/360

I use Length/360

So, acceptable deflection needs to fall less then L/360

L/360

120/360 = 0.3333"

And your Deflection from the program is 0.217". you need to understand this, I myself feel nor do I recommend or looked up the latest requirements for gantry calculations, since this program only calculates dead load, but in real world application, there will be impact or shock loads involved that may compromise it, you need to understand that its up to you.

http://people.tamu.edu/~mhaque/cosc421/DEFLECTION.pdf

Alternatively, by hiring an out-of-work (autobot)?...

Go Big....