Proper concrete for footings and distortion correction

J4 - Saturday, November 24, 2007 - 9:48pm

I'm currently working on a rail that is to be installed in a pre cored retaining wall with 3" dia. and 8" depth for posting. The stancheons are 1" sq. tube 1/8" wall.I generally use mechanical fasteners but since the holes were there and on fairly accurate 6' centres I decided totake advantage of them....... Question: what is the best mortar/concrete to use and should the metal (aside from being powder coated) be treated with some type of coating for longevity.
The bottom of the stancheons are open and the tops where they meet the top rail are %100 welded. One reason I'm concerned is some rail on an apartment I occasionaly repair which is set in sometype of dense dark grey concrete like (?)fixative has horrid corrosion, and although the welding on these is extremely shoddy ( ie. incomplete fusion, holes in welds, excessive porosity allowing water to get in from the top)I wonder if the installation into the fixative was suspect? These existing rails are no older than 30 years old.

Since I'm on a wordy tangent I have two other querries,

One is that of distortion correction or prevention techniques or literature that aren't directed towards ship builders and the like ( has anyone ever used Wagners 3 chock straightener?)

Two, possibly the unanswerable one that of bidding or pricing standards for non-commercial architectural metal?

Pointing me in any direction for any of these would be greatly appreciated.

Thank you

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Hi J4,

Canaday Designs - Sunday, November 25, 2007 - 1:59am

Hi J4, and welcome,
First off, pour-stone is the product I use for cored aplication, and it sounds like the rusted rail your talking about is because of poor fabrication and finishing of the railing.

as to the straitener, it works great just take it slow or you end up with a dog leg

and pricing, ha ha ha, good luck

#1 - your only as good as your last job
#2 - you will learn when it costs you
#3 - when you figure out the answer to bidding let me know

the bidding subject is a bit tricky, every geological area is difforant as to the market and demand, also every smith is difforan as to how much there end product is WORTH.
I for one would be more than happy to share money isues after I have seen your work. Not to be rude, but the product always comes first.

Matt

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Thanx Matt and Enrique

J4 - Sunday, November 25, 2007 - 4:07pm

Both very good answers on all points. And Matt, Ha Ha on pricing is exactly what I expected. It's definitely a tough one. I've often felt as if I were charging to much and to little at the same time.

Further more, you are both brilliant artisans and I learn much from viewing your works. I will try to get some JPEG's
up as soon as I buy an airporter for my Mac.

As far as geography goes I am in Seattle
Thank you again.

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I use roofing tar to coat

webminster - Sunday, November 25, 2007 - 12:03pm

I use roofing tar to coat the part of the metal which will be inside the concrete. Apply liberally and wrap it with plastic until installation. The reason for the plastic is because the roofing tar does not dry very well, and since you will be applying a thick coat, it likely not to dry until months later.

My understanding from talking with an architect is that the tar prevents the acidity from the concrete from passivation to the steel.

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i concure

alex b. - Sunday, November 25, 2007 - 11:25pm

Alex b. here in California, i don't know were you are, most contractors use "pour stone","rockite", which are name brands for non-shrink, it actually expands about 15% to fill in all the cracks, self leveling, sets in 15 minutes type mixture that comes in 10lb box's or 5 gallon buckets. King Architectural Metals {kingmetals.com} has the rockite and manufacture says does not have any additives that promote rust. $41.95 per bucket and they ship and will send you a free catalog. {i don't work for them, just use their stuff.}
When i install steel this way i always seal the bottom with primer and paint, if project is to be painted.
if powdercoat, then it is already coated.
if patina clear coat on part installed in the set.
i have used the "tar" as in "henrys" roof emulsion on the bottom of red wood 4x4 post for wood jobs, but have't used it on steel, but this does sound like it would work there also.
hope that helps.
as far as bibbing---------wow, i trip on that all the time.
from talking to clients, other contractors, and my wife, and even God. when a job is a straight forward time and material job, {meaning something basic like repetitive panels, or basic gates, or what ever it is you do, and all it will take is cut, weld, finish, install, i add all that time and material up, add on my profit margin and that is it. a very good piece of advice i got from someone, some were said, do not bid against some else or compromise your minimum needs financially to do a job. you will only regret it. bid it on what you must have and stick to it. i always tell the client that it is not my money any way, it is my wifes and my kids,and my churches. if i have to come down a little it is only in that "profit" zone and then it still is only a little.
one more,{i wonder if there is a message limit on these chat sessions?} as far as the "custom" jobs go. my experience has been bid as before,but also add on for that extra time, which is always more then you think it will be. extra time for me is the drawings, and re-drawings,the measuring and remeasuring, the changes and extra finishing touches that only you know about but must do so you can sleep at night and not worry that someone will see it later. the change in patina formulas cause it didn't come out right. the dreaded unknowns. and last is the fact that they want you to share a part of your self that is personal, your talent and heart for better then average, and better then they can get at "home depot". most clients who want "custom" know and expect this, if it is not special, they will let you know, and if it is, they will let you know that as well.
good luck and God bless you and yours.

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do not forget the little things!

FrankV - Monday, November 23, 2009 - 4:35pm

One tip I have is do not forget the little things and the consumables when pricing a job. Screws, fasteners, sand paper, bits, taps, acetone, etc. That stuff is materials too and can add up fast!
just my 2 cents worth.

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distortion control and correction

bebo - Sunday, November 23, 2008 - 10:02am

There is a book by a canadian fabricator by the name of John P. Stewart that is a tremendous resource for distortion control in steel weldments. Also checkout a guy who calls himself lotechman. I beleive he has a webpage on geocities. It has some great pics and descriptions of the causes, prevention, and cures of distortion.

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Proper footings for stancheons

hjnwt - Sunday, November 15, 2009 - 8:22pm

J4,

I would set anchor bolts if possible. Use Epoxy Grout to develop the strength. Most of the Epoxy Grouts develop 60K
PSI. Weld a base plate on to the bottom of the post with holes for the anchor bolts. Shim them up to 1" and place 4 nails on 90 degrees that can be removed latter to promote positive drainage. I would also drill two small weep holes just above the base plate into the tubing to allow any water that gets into the tube to relieve itself.

Hope this helps.

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railing notes

Stephen Fitz-Gerald - Monday, November 16, 2009 - 2:59am

Stephen Fitz-Gerald
I agree with hjnwt,weep holes are a must...
In addition I make sure whatever goes in the ground is solid metal ,NOT tubing. When I make a rail with 1 inch square tubing posts,I weld 8 or so inches of 3/4 round bar to the bottom of the tube with at least 8 inches up inside the tube as well. This is a good stiffener and means you get a solid bar in the ground.
Also I personally don't do any installs. I tell the client upfront that he must make a separate contract with a good contractor ,and then I recommend him mine.Ninety percent of the time they take my advice. I've been working with a fantastic and reasonable contractor doing my installations for 20 years.He has the PORTABLE TOOLS, the LIABILITY INSURANCE, and the CONTRACTORS LICENSE,none of which I have. I am always present for the install and WORK FOR FREE on that day,but shoulder none of the official responsibility.This arrangement has served me well over the years.
Bidding a job is often a sticky wicket.My technique is thus;
Since I DESIGN as well as FABRICATE,and nearly everything I make is site specific,I have a base price(or minimum) of $275 per lineal foot for the simplest of designs. Obviously curves or stairways are more difficult to execute so those are an added charge.My most expensive is about $500 per lineal foot (Art Nouveau stuff):
http://www.sfitzgeraldfineart.com/custom-gates/
(page two-The Guimard Gate)
Your question about warpage has two solutions;
First you clamp the shit out of everything you weld ON YOUR FLAT THICK JIG TABLE,especially if it has uneven spacing of the welds.Clamps are cheap,there is no such thing as "over clamping". Also I have consistently gone to thicker and thicker railing members over the years,cap rails,newels etc. to avoid heat warpage from welding.It's just easier and there's less chance it'll go haywire on you if it's thick and heavy material. This is of course even more true of stainless and other non ferrous metals...
I hope these logistics help.
But we're all different and have different strengths and weaknesses. These contrivances help me but that doesn't mean they would work for you. So take from this advice what fits and is helpful and discard the rest...In the end you want to feature your strengths and sublimate your weaknesses. How you do that is a personal thing...

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good advice

FrankV - Monday, November 23, 2009 - 4:40pm

Stephen,
that is a good idea to have a pro installer take care of it and just supervise. It is worth taking the day, even unpaid, so that way the job does not bite you in the behind down the road. Nothing worse than getting that angry phone call from an unhappy client days or weeks later!

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a question

FrankV - Monday, November 23, 2009 - 5:26pm

I just thought of this,
when adding the round bar to the end of the tube for the anchor, would you drill holes in it? I have heard of guys drilling holes in the anchor to let the concrete set in. Would that help or actually weaken the anchor and increase the chance of corrosion?

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I'll toss in a couple things

Rich Waugh - Monday, November 23, 2009 - 6:52pm

I'll toss in a couple things here:

Be sure that whatever anchoring cement/grout you use is above the level of the surrounding masonry. It doesn't need to be much, but it cannot be lower or it will pool water causing rust.

I agree with Stephen that solid anchoring members are superior. I won't use anything else. If tubing is installed below grade it will almost invariably condense moisture inside it and corrode below grade. Solid bar just avoids so many problems, plus it can be forged much more easily so I stick with that.

Tarring the outside of the steel that will be in the grout is a good idea - it allows a cushion for the differences in coefficients of thermal expansion between the steel and the grout. While epoxy avoids the issue of acidity/alkalinity, it still expands and contracts differently than steel.

90% of all corrosion problems are because of poor fabrication or finishing techniques. Concentrate on sound practices in these areas and you will have few problems when it comes to the installation and later performance.

Rich

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a couple of more things...

Stephen Fitz-Gerald - Tuesday, November 24, 2009 - 12:46am

Stephen Fitz-Gerald
Frank,
As regards drilling the end of the round bar that is the anchor; If it's tubing (which it shouldn't be as per Rich's excellent advice),then you might want to drill holes in it to let the concrete in...But any water trapped anywhere inside the rail will cause problems later on.Even a rectangular tubing cap rail should have little 3/16th weep holes every 4 feet or so.
I've been doing this stuff for years and actually never heard of coating the end with tar. I will be doing that from now on.
This is another example of the expansion of knowledge by forum and discussion.

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Frank, Drilling holes in the

Rich Waugh - Tuesday, November 24, 2009 - 12:59pm

Frank,

Drilling holes in the anchor does nothing if the anchoring grout is either epoxy or expanding cement such as Rockite. Well, it does, as Stephen noted, allow a place for water to begin corrosion. There is no upward lifting force applied to railings, so all you need the anchors for is lateral stability - no need to go beyond what is best practice for the industry.

Rich

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