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How to minimise railing movement / optimise shock absorption?


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Hi - I have couple of questions I wanted to ask to make sure my reinstated cast iron railings & gate have the best chance at long-term survival...

1. My gate currently swings open and bashes my (weak sandstone, relatively small) side wall, causing the side spindles to shake on impact. I'm sure I shouldn't leave it like this. Which of these options is best (if either)?
a) install rubber buffers (pix attached) on the sandstone side wall to dampen the impact , using a threaded bar held in with epoxy putty (I don't think anchor bolts are a good idea for sandstone?)
b) ask my blacksmith to weld metal squares onto the hinges of the gate, thereby restricting its opening swing to exactly 90 degrees.
I'm thinking the latter makes more sense as I'd rather the impact of any slamming (by posties etc) is absorbed by the original Victorian post than directly by the weak sandstone. But I'm unsure if the hinges could then become weakened. It's quite a heavy gate so the impact of slamming is significant.

2. On my longer front wall, the railings are still moving a bit when pulled (see attached video). My blacksmith used lead but he was more generous in some holes than others, and he did say I'll need to fill the holes with render. (The original Victorian spindles had been fully cut out - no stumps at all - leaving some pretty large holes). Should I:
a) insist he fills all holes with lead nearly up to the top, then overlay with Conserv sandstone restoration mortar 
b) pack some JB Weld epoxy putty in the less filled holes, then overlay with Conserv.
c) pack some portland cement in the holes (sacrilege for sandstone!), then overlay with Conserv.
d) simply fill all holes with Conserv.
My concern here is primarily about the sandstone. Conserv has a much, much lower compressive strength than cement, sandstone and even Lithomex (a different restoriation mortar that includes a % of cement, but I think is only supplied to trade). See this analysis https://heritagesciencejournal.springeropen.com/articles/10.1186/2050-7445-2-1/tables/2 So I'm worried about the potential for crumbling mortar / weakened spindle fixings after years of gate slamming.

Appreciate that 2 is more of a stone question, but I figured some of you might have an idea about best practice if you were finishing a similar job? Thanks :D
 

buffers.jpg

gate.jpg

spindle holes.jpg

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OK, this is something that is rather outside most of our expertise since, as blacksmiths, we are more involved in making things like fences and gates than mounting them or, rather, repairing old mountings.  However, I'll give you a couple of my thoughts and impressions, for what they are worth.

First, I'm assuming that you are in the UK from the license plate and buildings in the background of the photos and the fact that iron fences and gates are more common there than on the left side of the big water.  This is significant to your queries due to climate.  You have to consider a fair amount of precipitation but not much in the way of freeze/thaw cycles.

Second, as to your banging gate, it is probably not feasible to modify the size of the gate to fit the available opening.  Barring that either stops on the hinges or the rubber bumpers seem a reasonable solution.  I'd probably go with the bumpers since welding on cast iron is iffy and takes special rods and expertise.  Also, cast iron is brittle and I wouldn't want to put any extra impact forces on it.

Third, I think you need to fill the holes in the stone with something to provide a bit better base fit and to prevent water from ponding in the holes and infiltrating into the stone which could lead to deterioration of the stone.  More lead would do it but other compositions would probably do as well.  I'd try to go with whatever is similar in composition, color, and structural properties to the stone.  The lead is more traditional.  You are dealing with enlarged holes from the removal of the original fence.  The original holes would probably have been smaller and just a bit larger than the iron that was being inserted into them.

The question is whether the "wiggle" is the fence moving within the mounting material, the fence and mounting material moving within the holes in the stone, or just the natural flex of the fence itself.  I would look closely at the intersection of the fence and stone to see if I could detect any motion while the fence was being moved.  If I could not see any movement I would attribute it to the natural flax of the fence itself.  If there are any similar fences in the neighborhood, either old or new you could see how much movement is in them.

You might want to consider one or more angled braces near the center of the fence from near the top of the fence to the outside of the stone base, probably on the inside (yard side).  That would give a more solid mounting than just the fence uprights  inserted into the holes in the base.

These are just some thoughts off the top of my head.  Others may have some more specific suggestions.  Good luck.

"By hammer and hand all arts do stand." 

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Mount a rubber bumper to the wall like is sometimes done for door handles in houses.

Note LOCATION is very important to get good answers.  Where I live we have heat and terrible UV exposure so things that would last a decade outside back in Ohio; may disintegrate in a couple of months out here.  On the other hand we haven't had any rain for *months*!  You may also have some requirements to meet if it is a historic property.

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It's hard to tell where the flex originates from the video but it LOOKS like the pickets are solidly set and they are doing the flexing.  

None of the products you name are known to me so I don't know what properties you want. If you want more lead borrow or rent a lead pot and fill the holes. 

The only products I've used to anchor railings are "cyl cap" and an epoxy containing aggregate. Cy Cap is a mixture of sulfur and kaolin clay that is melted and poured it has excellent adhesion and neither shrinks or expands on cooling. The epoxy product is one we tested in the materials lab about 30 years ago, I don't recall the name or manufacturer. It was intended to anchor steel rods in stone well enough the steel fails before the epoxy does. We tested a number of these products to failure. 

Regardless there are numerous post and rock anchor products that would prevent any movement that isn't inherent in the fence itself. 

On occasion the end user wanted a hidden anchor, most people I know saved material drilled from the hole and covered the anchor material before it set.

What is the problem with using Portland cement or lime grout? It's been used successfully for thousands of years. Is there an issue with this particular sand stone?

Frosty The Lucky.

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It's a railing, not a hand rail, so I don't think you have a support problem. That means no one will on any normal basis be doing what your Wife is doing. Baring a car, a huge 300 lb drunk, or astronomically high winds, you shouldn't have a problem.  ;)

As for the unfilled holes, seems whoever did the install shorted you. I'd talk to him and ask him to finish the job. 

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If you install a bumper, make sure to place it at the sweet spot on the gate where it won't cause extra vibration. That's usually 2/3 of the distance from the center of the hinge to the far edge, but experiment a bit before you do anything permanent. 

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