Back on track welding up all the little short connectors to joining the joists to the containers. The 175 Millermatic is a good machine, functioning properly, and laying down some nice welds. Nice to have a welder that welds like it's supposed to.
I have contacted Lincoln asking them to fix my machine gratis. I have yet to hear from them. Bottom line, I need a new welder, and am leaning to the Miller 251, but am considering it because at times, I need it to be portable, going on the small ATV trailer, and the 251 couldn't do that as easily.
I'm too old to horse stuff around. I live in a VERY sandy area. A 251 with a 300 bottle on it would be past my capabilities. The hoist part of the project will help a lot, but there's no substitute for dumb youth and strength in some situations. That is not my forte now.
Steve has done rigging for years, knows how to do it properly. As in not dropping it off the side or the end.
A big problem with the 2x8 idea is when things are at an angle, want to slide off to the side. Or when parked on a hill and the ramp is going the wrong direction.
Something sneaky is when you have casters on the unit, want to go off the edge. So you put side rails on it and the casters dig into the SIDE of the rails.
And nothing beats an extra hip check by someone with some serious muscle to get it by the last little spot. And Steve is no longer in that category.
If it has casters, it doesn't work the way you think it will. Ask me how I know. I can send pics if you don't believe me. I had a small, 700 pound vertical mill mounted on 5" swivel casters that needed to go up an
8' long by 24" high ramp. Came pretty close to dumping it in a narrow space. Ugh.
Ditto on that. I learned early that when shit starts to fly, get to a safe place and watch. None of that stuff is worth a hand. When I was young, I grabbed a couple of out of control loads and saved the day, but not now. I will be installing many aids, but ramps in sandy soil, and pushing and pulling aren't in my play book any more.
BTW, does anyone know the bending strength of 60" long hitch stock? I want to use it to temporarily lift the Millermatic up and down off the canister roof. I'd estimate the welder weighs 80#. I think if could handle it, just wanted to be sure.
Heavy wall square tube used for trailer tongues . There's a piece about 8' long still laid over supports in my shop . I used it to hoist my 800# bench mill into position so I could slide the table under it - I'm pretty sure Steve's going to be OK using his 5 footer to lift a couple hundred pounds of welder and bottle .
Hitch stock is the 2" x 2 " heavy stuff that the slider part of your hitch is made out of. Not the female part, the receiver, but the male part. IIRC, it is made differently as to finishing, and is stronger than a tube of equal dimensioned 2" square tube. It also has the corners finished off a little different, and no seam ridges so it slide in and out.
OK , I was a little off in my description ... and though the piece in my shed is 2X2 , it's probably not hitch tube . But it did work well to hoist my mill in the air . But I wouldn't stand under the mill while suspended ...
I know my 200# 6'2" 18 year old helper is sure going to like it. Now we have to go up and weld it all out, and hoisting all that up is a two man process, and even for two men, a little tiring. I think I may use it to hoist the 16' pieces of 3 x 3 x .120 into place for the hoists. This stuff is actually fun. As long as everything goes to plan ................... I've watched some pretty big stuff fall.
Snag, or anyone .............. What is the actual dimensions of hitch stock, is there any additional finishing of the surfaces or corners, and is there any heat treating after forming that adds strength? I know the stuff is God awful strong, and I do not ever recall seeing a bent piece.
Most hitch tube is made to telescoping tube specs with an inside dimension of 2"x2". Each manufacturer will play with the specs so that the actual inside dimensions will vary from one to the next. I have one section that is terribly loose, measures 2.084 inside. Since the typical carrier is around 2.005 to 2.020, it rattles a lot. Wall thickness will depend on final application. You can use thinner material for a tube used on a class III than a Class IV hitch. And that depends on the length in the specific application.
All this sort of tube is rolled up from strip stock, welded, then run through a 'turkshead' roller (4 rollers set at an angle) to make it square stock. By varying the width of the input strip stock and the settings on the roller, you can make pretty much any size you want on the same equipment.
Standard ASTM specs for square tubing allow for the outside corner radius to be 3x the wall thickness. If a manufacturer wants to skimp on materials they run the round tube on the small side, just put some simple flats on the sides. I've seen some 2" square quarter wall that had only 1" flats on the sides and still met spec.
But if you want to telesscope a tube inside you need to make sure the inside corners are really square to avoid conflict with the nesting tube. Plus you need to get rid of the weld flash (done in the weld station). Plus you need to make sure the tube is SQUARE (adjust the turkshead correctly.
hard to say if the tube is made from anything other than hot or cold rolled mild steel. I've seen hot rolled spec product that was obviously made with some off spec cold rolled. That was some NICE tube but much tougher to deal with than the regular product.
You weigh more than the welder, just put the pipe on supports and do a careful chin-up. If no excessive sag, you've got what, at least a 2:1 safety margin?
Surely hardly likely to be anything but "mild steel". What we call S275 or S355. (number is MPa nominal yield - so that's 40ksi and
50ksi). So no heat-treating or anything like that, at all at all.
I'm asking a question, but hopefully of interest to the OP.
Unless you are really sure you want to forego this for ultra-light weight you make your section "plastic" so it won't locally buckle and "give-up" after only limited initial elastic spring. So you make the walls thick enough that it will keep on bending in overload - and keep on bending... Strength does nothing to change this, which is due to thickness to section-height ratio. If you can't reduce your thickness, there is no point increasing your strength... For I-beams, that means there is no point going over 275MPa yield. For boxes, you can meaningfully use 355MPa steel. Up to and including 355MPa steel is fully weldable and non-heat-treatable essentially "mild steel".
For trailers at the towing part, the section is definitely going to be "full plastic moment capacity is attained"..???
Have I got this right?
So for the OP, use the section as-is. The good news is, if you overload, you will see initial plastic deformation - and that onsets gradually as deformation creeps inward from the outer "flanges" to the neutral-plane plane along the "web" (know the terminology doesn't naturally make so much sense with SHS's and RHS's - "box-sections"). Enough warning for the careful load-lifting by the observant?
I picked up a steel design book -- then thought about my own project deadline...!
Perhaps rope it with a short beam roped and drifting near the floor and stand people on it as makes 1~1/2 times the load you are lifting.
Interested if anyone can comment whether seeing this rightly.
Square tube will always buckle at the point of highest load, it is not distributed. Failure mode is buckling of the side walls. Buckling is technically a function of the modulus of elasticity ie if it's stiff enough it won't buckle. Since all steels (regardless of strength and yield) are pretty close to the same 29x10^6 modulus, the only way to make the walls stiffer is to make them thicker.
The problem with doing testing of square (or round) tube when used as a beam is that the failure is quite abrupt. Once the buckle starts, it just caves in. To make matters worse, any imperfections in the tube wall (manufacture or from use) make the buckle start at lower loads.
On a purely practical note, square cross sections are not very strong when used as a beam. OK, much better than an angle piece of the same size and weight but still not really a good load bearing element.
Purely as an aside, when I made the sleeve for this hoist to go onto the square tube, I made it about 14" long, as long as the hoist is, so the load is distributed to two sleeves 14" apart, and not one in the center. I think that may make a little difference. If I need to make a hook attachment, I'll just cut a pup that will slide into the receiver pieces with a hook on it.
Last evening, we just lifted all our gear on top of the containers. This evening, we hope to get the hoist working and use it, as we have to hop around a lot on the containers, and this will take away a lot of work lifting it up and down, or over and through every joist. Looks like it is going to work, and as I get the lateral stabilizers/anchor horizontals in, the thing is stiffening up incredibly. Going to work again tonight from about 5 to midnight, those big metal halide lights make if daytime out there. Temps in the 70's. Just pray to the wind God he stays away.
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