Best way to section test 1" solid round to 1x3" 11ga tube?

   / Best way to section test 1" solid round to 1x3" 11ga tube? #11  
Solid is overkill with 11 gauge tubing and would add a lot of unnecessary weight. If you used tubing you could drill holes to fit the tubing through and just weld the outside. You wouldn't want to drill through both sides because then you'd have a hole in the round tubing to fill with water. A decent fillet weld around a 1" dia. tube will be plenty strong. My first job welding out of school, I built hooped safety ladders for large oilfield tanks. I made a few hundred of them in 7 1/2 month's. Tacked in a jig then stood on edge with just a 7018 donut weld around each 1/2" rung. I've seen some that had holes drilled and then welded on the backside but that's just a lot more work that isn't required if you do a decent weld. 1" diameter is over 3" of weld around the circumference. You'd bend the thing like a pretzel long before the welds would be a problem.
 
   / Best way to section test 1" solid round to 1x3" 11ga tube?
  • Thread Starter
#12  
I would bore the near side of the tube and recess it. You don't utilize the strength of the rectangular tubing by butt welding to one side of it. I would also drill a 1/2" hole opposite the 1" hole and plug weld the end of the 1" round stock stock to the back side of the tubing as well as the near side. Boring 60 holes in 11ga. really isn't a big deal if you are even moderately set up to do it. If my grandkids were going to use this I sure wouldn't be choosing a design based on ease of construction.

Hence the question here on testing it. Thanks for the input, I think I am now tending to recess these into the tube. It'll help with fitup (no jig required) and probably look better overall. Plus, as you noted, it would be stronger.

Part of what I was trying to do was avoid buying the hole cutter. I didn't have one that size anymore. I went shopping online last night and am about to punch the purchase button now for a rota-broach set, plus an additional 1" cutter.

Thanks again.

Solid round stock seems like way over kill unless that is what you got to work with... especially if you are paying for it aw well. Tubing to tubing with similar wall thicknesses would be easier. I definitely like the idea of boring a 1in hole on the insides of the rails. Then your weld can be prettier than strong and no one the wiser. But this is coming from a rookie welder FWIW.

1" solid was easier to get at a good price, and matched some of what I had around already. Believe it or not, the solid was almost the same price as 11ga round tube. I bought extra for another project.
 
   / Best way to section test 1" solid round to 1x3" 11ga tube?
  • Thread Starter
#13  
I would bore the near side of the tube and recess it. You don't utilize the strength of the rectangular tubing by butt welding to one side of it. I would also drill a 1/2" hole opposite the 1" hole and plug weld the end of the 1" round stock stock to the back side of the tubing as well as the near side. Boring 60 holes in 11ga. really isn't a big deal if you are even moderately set up to do it. If my grandkids were going to use this I sure wouldn't be choosing a design based on ease of construction.

Solid is overkill with 11 gauge tubing and would add a lot of unnecessary weight. If you used tubing you could drill holes to fit the tubing through and just weld the outside. You wouldn't want to drill through both sides because then you'd have a hole in the round tubing to fill with water. A decent fillet weld around a 1" dia. tube will be plenty strong. My first job welding out of school, I built hooped safety ladders for large oilfield tanks. I made a few hundred of them in 7 1/2 month's. Tacked in a jig then stood on edge with just a 7018 donut weld around each 1/2" rung. I've seen some that had holes drilled and then welded on the backside but that's just a lot more work that isn't required if you do a decent weld. 1" diameter is over 3" of weld around the circumference. You'd bend the thing like a pretzel long before the welds would be a problem.

Thanks for the input. I might just drill them to avoid the jig setup. Just making one of these for now.

Solid is overkill, but it was a good price and the overage is for another project.

Oilfield ladders with 7018 rod on small rounds...sounds like a lot of time learning to contort your wrists. I'm sure you got a pattern worked out and could do the motions in your sleep even now via muscle memory.
 
   / Best way to section test 1" solid round to 1x3" 11ga tube? #14  
For a gym set, a couple of solid tack welds would hold as much as you can put on the box tubing. Using a 70xx electrode or even MIG would mean that with just a 1/4" long tack would hold several tons of force.

I think you are overthinking the welding issue. Just weld it with a fillet around the joint OR put a hole in one side and tack weld everything together. Then turn up on edge so it is a flat weld and weld it the best you can. Just a bit of solid weld is all that you need to keep it together for a gorilla swinging on it.

The WEAK link is going to be the span of the box tubing. If it holds without bending, your rods aren't going to be a problem even with just small tack weld on 2 sides.
 
   / Best way to section test 1" solid round to 1x3" 11ga tube? #15  
XMS. The 1" RotaCut requires a larger arbor than the smaller ones in the set. You may have to purchase it separately. I also purchased extra arbors so that each cutter had its own. Just thought I'd help you spend your money:) Terry
 
Last edited:
   / Best way to section test 1" solid round to 1x3" 11ga tube? #16  
This is going to end up much stronger than those wooden ladder things that rot over time. I never really cared for the monkey bars, but I liked the thing everybody jumped on and pushed in a circle like crazy.
 
   / Best way to section test 1" solid round to 1x3" 11ga tube?
  • Thread Starter
#17  
For a gym set, a couple of solid tack welds would hold as much as you can put on the box tubing. Using a 70xx electrode or even MIG would mean that with just a 1/4" long tack would hold several tons of force.

I think you are overthinking the welding issue. Just weld it with a fillet around the joint OR put a hole in one side and tack weld everything together. Then turn up on edge so it is a flat weld and weld it the best you can. Just a bit of solid weld is all that you need to keep it together for a gorilla swinging on it.

The WEAK link is going to be the span of the box tubing. If it holds without bending, your rods aren't going to be a problem even with just small tack weld on 2 sides.

I was definitely over-thinking it. I did the math on a 3.14159" fillet and it's pretty much gonna stand any test so long as I don't use chewing gum. But even then, some brands of gum will probably hold. Wrigley's pretty much turns to solid gunk after a few minutes, and when it gets wet it might as well have been filler metal. I think I'm just going to use the rain this week to build a jig, and then when it clears I'll put it together. The wife wants it in the basement this winter for the kids.

My primary welding is furniture (racking, etc.), tractor junk (heavy plate), logging tools and some structural. Otherwise the thin stuff is all just tacked together - nothing I ever had to put weight on (but none of it ever broke, either). All rod and some flux core. Getting into more delicate stuff with MIG and TIG, so not sure I can 'Kentucky Windage' things like monkey bars, yet. Hence the idea of cutting it and finding out if my guesses were close enough. Thanks for your advice; I will heed it.

XMS. The 1" RotaCut requires a larger arbor than the smaller ones in the set. You may have to purchase it separately. I also purchased extra arbors so that each cutter had its own. Just thought I'd help you spend your money:) Terry

That's good to know. Thank you.

This is going to end up much stronger than those wooden ladder things that rot over time. I never really cared for the monkey bars, but I liked the thing everybody jumped on and pushed in a circle like crazy.

Don't forget the splinters. Hate the splinters.

Those rotating carrousels are monstrously awesome, which is why they are now banned from pretty much every new playground today. There is still one at the park we enjoy, but our new school asked for help in putting up a new playground and I guess the list of "cannot insure" is so long they just said 'eff it and built a 'natural playground'. Key feature is a massive sandbox built using my tractor, some logs and about 24,000 pounds of play sand. The kids were digging in it before we were done hand-leveling the thing.

They pulled a bunch of swings and monkey bars from a Florida beach public playground where we go in the winter and where the wife & kids spent most of this summer. The rebuild is a big pirate boat that is pretty cool, but it has nothing to hang from or to swing from. It's basically nothing more than stairs and a totally enclosed slide, which gets about the temperature of the sun in the summer. At least that part is the same from my childhood.

Part of this project is building all the cool stuff they are yanking from the schools and parks. Our kids are monkeys, and I'd rather them climb the monkey bars over a sand pit, then climb those oaks I got out back in the woods. Sad to say, but if I catch them climbing the stuff I did as a kid...

It's in the their DNA. I climbed and my wife spent half her life looking at cliffs in places like Yosemite and finding her way to the top one hand over the other. My three year old saw a rock climbing wall last week and gravitated to it like a moth to a flame. So we call this a controlled compromise. For now.
 
   / Best way to section test 1" solid round to 1x3" 11ga tube? #18  
I was definitely over-thinking it. I did the math on a 3.14159" fillet and it's pretty much gonna stand any test so long as I don't use chewing gum. But even then, some brands of gum will probably hold. Wrigley's pretty much turns to solid gunk after a few minutes, and when it gets wet it might as well have been filler metal. I think I'm just going to use the rain this week to build a jig, and then when it clears I'll put it together. The wife wants it in the basement this winter for the kids.
That particular math is not he issue. The issue is that the rect tube is loaded from only one side and will therefore twist a little with load. The cyclic weld stresses which will show in the math for this case are what is relevant. The result will finally crack the metal in or near a poor weld. Pay good attention to those welds and youre OK. That means you want a nice fillet so blending between the rigid solid bar and the tube is gradual rather than abrupt. Post peening with a needle scaler will also help resist a crack starting.
larry
 
   / Best way to section test 1" solid round to 1x3" 11ga tube?
  • Thread Starter
#19  
Larry (and others),

Thank you. Just when you think you're smart, the internets show you wrong.

- Patrick
 
   / Best way to section test 1" solid round to 1x3" 11ga tube? #20  
I know how this works if you already bought the material and want to use a weldor on it. You received some good advice here.

About 15 years ago, I had to build a structure out near my barn to keep my daughter happy outside the barn while I was happy inside the barn, only few yards away. I used treated 2X4s instead of 1X3 steel tubing, and steel conduit instead of 1 inch diameter solid steel bar.

The 2X4 treated rails were drilled with a cheap spadedrill, slightly large than the conduit diameter on something like, 18 inches between centers. They were of a consistent depth, maybe 3/4 inches into each board.

I cut each conduit rung to a consistent length.

On the rails, the first, last, and several in-between conduit holes were drilled thru concentric with the conduit hole so that threaded rod could be inserted thru both rails and the conduit to keep the assembly sandwiched with nuts on each end of the all-thread.

Sadly, the kids grow up faster than the boards deteriorate. Happily, you can disassemble it and use the components for something else.
 

Tractor & Equipment Auctions

2014 International DuraStar 4300 4x4 Terex BT3063 63FT 15 Ton Crane Truck (A51692)
2014 International...
2025 Mower King SSBM72 (A50123)
2025 Mower King...
2010 THOMPSON TRASH PUMP (A51406)
2010 THOMPSON...
(4) 250/80-15 Solid Forklift Tires (A52384)
(4) 250/80-15...
2011 John Deere 5075M 75HP 4WD Loader Utility Tractor (A52377)
2011 John Deere...
2016 Ford F-550 Crew Cab Mason Dump Truck (A51692)
2016 Ford F-550...
 
Top