Custom Fabrication

I want the walls to be nice and plumb.  This is usually managed with diagonal bracing to position and keep the wall where you want it.  To add a bit of finer control over the wall, you will often see builders use a turnbuckle.  These allow the builder to make fine adjustments. Often these are needed both to plumb the formwork and to help brace against concrete blowouts, etc. so they need to be big strong expensive things… Sometimes you see whole systems of bracing…

In the system on the right, the yellow parts are threaded and can be turned to adjust plumb.  They also provide a nice working scaffold for the second half of the wall, brace against the concrete, etc.  These cost hundreds of dollars each, but would be totally worth it if I were an ICF contractor.

In my design, the steel studs are considerably lighter, so they will be much easier to push into plumb.  The walls are curved and the studs will be tied together with the metal lath, so they should be able to resist the shotcrete on their own.  This frees me to go for a much lighter design.

I got some inspiration from this example (on the left).  You can see that the bottom is a piece of angle iron screwed into a 2×4.  They welded a nut to the angle iron with a threaded rod connected to another bracket that they attach to the vertical form work…  The end of the threaded rod is cut to take a screw driver. Adjustments turn the threaded rod and make it move thru the welded nut.  This allows for fine adjustments on the overall lengths of each support.  Adjusting the length provides the fine tuning needed to plumb the wall.  I can buy a turnbuckle like this from an ICF distributor.  The problem is this little piece of hardware costs $16.99, plus shipping, and I would need a bunch of them.

So I made my own.

 

 

 

I used my new welder to weld the nuts to the angle iron (less than a minute).  Then I used my grinder to make a hex end on each threaded bolt so that I can drive them with a socket on my drill (just over a minute).  I ended up making 3 different sizes, 1/4, 5/16ths and 3/8ths, just so I could compare them.

I could get 1/4 inch locknuts from Home Depot, but they don’t carry them in the other two sizes.  I could probably order them for 5/16th and 3/8ths, but I ended up just tightening two regular nuts together for a similar effect.  The rest is just a 6 inch bolt in one direction (for the length adjustment) and a 3 inch bolt in the other (for a pivot), plus washers…  I will screw the second wood block into the steel studs and the angle iron gets attached to an 8 ft piece of 2×2 wood which is staked into the ground.

Total cost is less than 2 dollars each for the big one and almost down to a dollar for the 1/4 inch version.  I would need to make about 40 of these before the savings would pay off my welder and related tools.  The 8′ piece of 2×2 costs and additional $1.50 each.

Here is a close up on the welded nut and ground hex end.

 

Tomorrow, I will try these out before making any more.