Happy Feet!



Was able to get three of these completed this weekend. As like most of my projects, I was side tracked and Shanghai'ed by the unexpected. This time it my eyeballs. At first I thought I was having an allergic reaction to Texas Spring-time. Turns out there was a crack in my welding hood lense. So for most of Monday I had bloodshot red eyeballs which felt like someone threw salty beach sand into.


The area in which I am building is notorious for its black clay-based mud and shifting soils. Because of this, most traditional variations of slab on grade construction is problematic. Instead of pouring a reinforced monster slab to build a house on, I am going to pour (6) concrete pylon/pads. On which these feet will be connected to either by concrete anchors, or I may weld rebar to the bottom of the pad and set them when the concrete is still wet.

The foot itself is adjustable in elevation by (2) 3/4" pieces of all-thread about 6" long. These all-thread pieces are connected to the bottom base plate by a welded on nut. These nuts were originally plated. I sandblasted the zinc coating off with aluminum oxide prior to welding.



Some may wonder why I did not just weld the all-thread directly to the plate. I could have done that, but this system is a bit easier and more flexible down the road. What makes it easier, is that the threaded center and the flat top and bottom surfaces on the nut are perpendicular. So, by clamping and welding the nut on, I did not have to use too much effort making the all thread plum to the base plate. But this was really only secondary...

By using the nut as the connection part, I can thread in my all-thread rod. Because they are threaded coarse, there is a limited amount of wiggle in them. Once the foot/anchor elevation system is finally set on each foot, I will place two tack welds on the base nut, locking the all thread into place.

This way, should the concrete bases these sit on shift more than 4", I can just grind off the tacks. Then unscrew the all thread and screw in a longer piece. then just tack it back together.

After these feet are in place, and the elevations of the beams they hold up are set, I will fabricate some shim stands. These will also be made from 3" square tubing. They will be custom cut to length, and sit in between the two sections of all-thread.



The plates themselves are 1/4" steel pieces of scrap from Stirling cycle heat engine test prototypes. The holes were all laser cut. The top plate is actually 1/2" thick along the edge. You may be able to make it out in the above photo. This was a laser cut piece which was bolted onto the plates like a really thick gasket. My thinking was that this extra material would help keep the flange more perpendicular to the post over time.

Over the past few months I have been talking with various board members about this. Just wanted to show you guys what I have been doing, and show how I applied your combined input.

Looking good and it is more flexible as you stated.
How many feet do you plan to use?

Sorry about burning your eyes. It happened to me once and I thought I was going to rip my eyes out it hurt so bad.

Its been about 12-13 years since I last had welding flash burn on my eyes. For the most part, I am fairly resistant to it as I can handle indirect arc-light exposure without too much difficulty. But a crack in the lens is different. So today, I am going to try an hunt down a new hood so I can complete my cabin support/beam assemblies.

My plan needs six of these feet. Three to hold up each beam. Two beams total.



My goal is to create a universal 16x20' platform base. The 320sq/ft decks can then have different styles of buildings on them. Or be built side by side to create larger buildings. The drawing above is for a cabin which I am hoping to complete for around $3k. It will only have a 12x16' enclosed area with a 8x16' covered deck in front.

If it works, The next building is going to be another 16x20' building. Totally enclosed. This one will be geared specifically to have a fully functional kitchen, bathroom/shower stall, and laundry facilities. Later I will probably build another building connected to it via a short suspended walkway to be (2) 10x16" bedrooms.

Two suggestions First is potato on the eyes for welders burns. Cut a slice and place on your eyes for an hour. It works, I used to work with sparky the non warning welder.
The next is putting a piece of plastic hose over the all thread with grease in it. That will preserve the threads for a bit longer. I use that on my welding stand that stays outside. I like everything on the level when I start a project. I used heavy plastic tubes and put in grease zerts. I never use all the adjustment anyway.

Finished fabricating my angle iron beams today. Right now they are baking in the sun with the first coat of primer.

Those look great. Good looking welds too. How did you get that primer on those beams? Did you spray them?


Edit: I looked at the picture again. I'm guessing you didn't spray them with the car right there, and I don't see any over spray on the ground. Brushes work well, but spray equipment can be useful too.

I used a 4" roller. I have a spray gun which I considered using. But ended up just doing it by hand. The small rollers I have found work great when coating long lengths of steel. When the part you want to pain has a bunch of twists, or corners, thats when spraying helps.

Looks good. Am I right in assuming the joists will be bolted through the holes in the angle iron? If that is the case, you'll have the joists on what, 12" centers?

Looking forward to future updates.

Looks great! Did you drill all those holes on a drill press, or by hand? I'll bet no matter what you used, that was a chore.

The holes are on 12" centers. The deck pieces which I plan to use are going to have some type of wood runner which sits between the deck and the beam. All the deck parts are going to be pre-fab'ed in 4'x16' sections. Those will have 2x10's on 16" centers. Underneath will be hardi-board concrete composite siding material. Then strips of either pressurized 2x12's or perhaps laminated 3/4" plywood strips. Two four' strips on 12' centers to match the beams. 3/8" lag screws with washers will then go through the beam into the strips which hold the decking material on.

I thought about doing the holes and try for an exact alignment with the floor joists. But instead chose the strip method because its flexible for field construction. Meaning I can hand some "slop" in the actual construction but still have it look good.




Actually it took about an hour to do all 42 holes in each beam. I did not drill however. I used an oxy-acetylene torch to burn the holes. It was much quicker than drilling. One of the reasons why I like doing the side by side angle iron design for beam applications is because its so easy to align and weld. Also the flange sections are very tolerant and predictable when it comes to heat distortion from welding and cutting. If I tried cutting the holes like that on tubing for example, it would bow into an arch along the length far more drastically that the angle iron.

The legs are mostly scrap material I had at the house. The 3"x4"x1/4" angle cost about $75 a stick (cash... no receipt ). I am estimating that I can build each one of those beams for about $250 each.

It looks kinda like what I was talking about, but better. Did you do the welding in your garage? Do you use CO2 as a shielding element or a mix?

I use straight CO2 as a sheilding gas. There is a lot more spatter than using the more popular 75%Ar/25%CO2 mixes normally used for MIG (GMAW) welding. Its also harder to weld "pretty" with straight CO2. But the advantages are that you can get better penetration, and a bottle of CO2 lasts nearly forever. I am using the same bottle I bought in 2001, and I still have 2/5ths of it left.

For the welding wire, I am using a 30lb spool of EASB 0.035" E70-S6 general purpose copper coated wire.

I have a 1995 Hobart Beta-MIG 170. Its a great general purpose machine for projects up to 3/8" in thickness. I can do multipass techniques on thicker weldments, but typically I will not even tackle projects of that magnitude with my equipment.

Yeah, CO2 is cheaper. I really don't notice much difference when switching from mix to CO2. There probably is more spatter, I always thought it worked just as good. Maybe because I was using them on two different applications. At the time, I was using a mix at work for fabricating grain elevators and screw conveyors, then I would go home and use CO2 on the dune buggy that I was building.

It takes some skill (and a clean tip) to use a torch instead of a drill, to burn those holes the way you did.

Oh yeah, you're a welder at heart! You guys just love to torch the holes instead of drill them. We engineer types frown on that. But usually we're designing bolted connections for shear strength, and a ragged hole just doesn't cut the mustard. For your purposes, though, considering the time savings, I can see why you did it. It's just one of those things I constantly fight here at work. I have to constantly keep an eye on anything I design that's built in our yard, because those guys will just torch a hole without thinking about it.

Yeah.... if I had access to a hydraulic IronWorker I would have punched the holes. On bridge crane systems its just an accepted no-no to flame cut holes. The beams I have are a way overkill for my needs, so I am not too worried. Its not like I am building a high rise. I just need to keep my stick cabin connected to the steel frame. I'm hoping that (84) 3/8" lag screws can do that.

Out of curiosity, what if I used an oversized washer... Perhaps doubled the washer up. Then tack welded it on for sides over the flame cut hole. would this increase the shear strength of the bolted or lag screwed connection by any considerable amount?

Honestly, I don't think it will matter in your case. The bolted connections are not going to be your weak point in the design. The lumber connections will. If, for example, your cabin were hit by a tornado, the lumber will simply tear off before the bolts fail at the beams. Nailed, screwed, or lag-bolted connections will be the first to go. So I think you're just fine with the torch-cut holes. If something catastrophic happened, they'd likely stay put while the wood came apart.

well at least the holes will help make the beams a bit lighter to load on the truck...

Those machines are awesome. Even though I almost lost my thumb to one. They save so much time.

Finished (3) 4'x16' floor subsections this past weekend. Each section is made up of (4) 2x10's 16' long. Lowes had these on sale this past weekend at $12 ea. I had some 10% coupons to boot, so I was pretty please to buy all my lumber under budget.



Three of these platforms will be placed on the steel beams side by side to make a 12'x16' deck. Where each section meets, there will be two side by side 2x10's. This is overkill I know, but its going to be a month before I get these out to the build site.



In the above picture, the floor is actually upside down. Because each of these floor pieces will be suspended off the ground, I used "Smart Siding" panels on the bottom. There is a 3" gap between the two panels in the middle of the floor section. 16' lumber plus the wood on the ends works out to being about 16'3"



Pressure treated lumber is used on the bottom. 2x12" pieces are where the wood deck assemblies will sit on the steel beams. The steel beams have holes on 1' centers where lag screws with washers will be used. a 2x8" pressure treated piece is used to cover the gap between the smart siding. If I have any bowing issues in the center of the floor sections I will lag screw a 3x3x3/16" piece of angle iron on the bottom center to help force all platform sections in line.



All weather spray foam is used in the gaps in the center.



R-19 combination sound and temperature insulation is put in the floor sections. This was another on sale component, where it came in 93" sections. So I ended up using some R-13 wall insulation scraps I had floating around.



3/4" subfloor plywood is then put on top. This is the first layer. After these sections are installed on the beams, I will put down a second layer overlapping all the seams. Then followed by some other kind of underlayment. Finally, I will be using laminate flooring as the final layer.


This weekend I am planning on starting the walls.

How much does that floor section weigh?
Are you going to have to use some sort of lift to put these in place?

Probably his friends.

Wow you're doing a great job! I feel like I'm looking into the future, my hubby is a metal worker and planning to learn to weld soon and we want to build a house in the next decade..

It's cheaper than the mexicans...

I have some questions. Why adjustable beams? You building on quicksand? Where in the state are you?

Theduardo will be building his cabin on his property which is pretty much swampland. Considering the expansive soils he has, it's a good idea to build in some adjustability to the design, in order to accommodate settling. He originally discussed the idea in this thread.

I just wonder why more homes aren't built with adjustable piers. It sure beats having to pay thousands of dollars a couple of years later when the doors will no longer close properly and the walls start cracking.

Houseboat! I hunted as a kid down south of county road 4110, I used to squirrel hunt, that is swamp country. I always concidered people should live in house boats in that area. Although he may have better conditions than that where he is building.
I just picked that up when visiting a friend of mine years ago before he died. His family lived in Acme Louisana(google map it). One road in one road out, but for years when I was there we could only get there by boat.(You talk about hearing banjo music in your head, swamp) I would bet his conditions are not that bad but Houseboats are the norm for foundation reasons. They use a pontoon boat for a base and add on. Some are bolted together and have large rooms.
I am not suggesting this is what Theduardo should do but its an idea.

purple puts his two cent in his pocket and walks on.