Below are restoration tips offered by various collectors. Any given problem has more than one solution ... different people have found different solutions for the same problem. You will have to decide which best suits your situation.
The following topics are discussed. Click on a particular topic to go directly to it.
1. Displaying Hydrants
Before you bring your first hydrant home you ought to consider just how you will be displaying it because this dictates just how much of the hydrant that you need to bring home. How a collector displays his/her hydrants depends upon personal preference and space available. As can be noted on the various collector pages a great variety of means of display have been used.
2. Cutting Hydrant Barrels
Most city workers or scrap yard workers will not use a cutting torch to cut hydrant barrels because the molten cast iron will pop or explode in unpredictable directions. So I have not pursued using a cutting torch myself. Instead I saw them with abrasive metal cutting blades.
I used to bring the entire hydrant home in the back of my pickup only to have to saw it off with my electric circular saw using an 7" abrasive metal cuttting blade. But then I had to load the lower portion back into my pickup and to haul it to the scrap yard myself. I eventually decided to buy my own Stihl gas powered chop saw (~$900) like city workers use. This allowed me to bring home more hydrants from more cities since I didn't have to put them through the hassle of sawing them off or loading the complete hydrant. I use my chop saw to make a rough cut about 6 inches below where I will make the final cut at home using my circular saw.
Other options to buying a new chop saw include renting as needed or buying one used from a rental business.
The 14" metal cutting abrasive cutoff blades for my saw cost $9 - $11 each. I have never documented how long one lasts but I would estimate 8 - 12 barrel cuts; unless you get a sizable knick in the abrasive blade and then they are ruined. So you have to exercise care that as the last little bit of material is cut that the heavy barrel doesn't pinch the fast rotating blade and pinch a little chunk out of the blade. It is frustrating to have a large diameter left and it not cut because of the small chunk missing. The safest bet is to leave a small bit of material in the cut and kick the barrel in two or otherwise move it to break the last little bit of material.
One other thing to contend with as you cut a dry barrel hydrant apart is the operating rod. I have run into three basic types:
1. It "plugs" into the bonnet area (like a wrench socket) so that once the barrel is cut in two it simply unplugs and the two barrel pieces come apart at the cut. Typical brands with this type are Iowas and Ludlow List 75s.
2. It screws into the bonnet. Some screw all the way out (via opening the main valve by turning the operating nut) while others have a stop feature built in. I usually open the main valve all the way before I cut as it seems to operate easier than after the barrel is cut and things aren't lined up as well. After cutting you will find out very quickly if the threaded rod has a stop or not! If no stop the barrel can be pulled all the way apart. If the threaded rod has a stop then the barrel halves can only be pulled apart in the amount that the valve opened. This 3 - 4" gap is usually enough to reach in with the chop saw blade to cut. Most other hydrant brands fall into this category.
3. It is seized and cannot be turned. These typically require a second cut so that you can break out a ~4" wide section to be able to reach the operating rod with your saw. This may require a lengthwise cut or two between the two circular cuts so that you can readily break these pieces out of the way. With smaller diameter barrels and a fresh blade one can usually cut the operating rod at the same time the barrel is cut; however with ~5" V.O. barrels and a used blade I usually can't get the operating rod cut with the barrel.
As you can see having the appropriate wrench for the operating nut is a valuable tool. A pipe wrench works if the operating nut turns easily but one really has to be careful not to round off the corners of a pentagonal nut. If you have a square nut then a large crescent wrench is the answer. (contributed by John Anderson)
3. Repairing Nozzle Thread Damage
Occasionally the hydrants I bring home have damaged brass nozzle threads; typically from being handled in the yard without a cap in place.
Minor to moderate thread damage: I use a small triangular metal file that is about 3/8" to a side. With a triangular file each edge has a 60 degree included angle ... which is happily the same angle as used in making the male brass threads of a nozzle. So I use this file to dress up the damaged threads so that the cap can spin on. A simple and quick fix.
Major to gross damage: I have resorted to literally cutting out a portion of the nozzle. A cap will still spin on with an amazing amount of nozzle thread cut away. All these threads have to do is hold the cap on for display; they no longer have to be 100% intact for leakage, etc. My usual cutting tool is a 3" diameter abrasive wheel on a die grinder; although a hack saw works for most instances too. And then follow-up with the triangular file to remove burrs created by the cut. Obviously one should avoid hydrants with gross thread damage; but if the hydrant is rare enough this major surgery is a viable option.(contributed by John Anderson)
4. Repairing Broken Cast Iron
If you are thinking about welding ... forget it! Cast iron does not weld. A highly skilled person can braze cast iron together but the high heat can distort the iron and can be expensive. And you still have the appearance of the raised braze bead to deal with if it is on an outside surface.
I recommend "gluing" cast iron together. A good product to use is called J-B Weld. It is a two part epoxy adhesive that comes in small squeeze tubes. Follow directions on the package. This stuff does not make a good filler material because it is somewhat runny before it sets up. It costs @ ~$4.00 per package. (contributed by John Anderson)
5. Bolt & Stud Removal
You might want to try PB BLASTER.....lots of it and a some time. The stuff is simply amazing! (contributed by Dave Raupach)
My Greenberg 54GR has studs which hold the valve assembly to the barrel, and two of them broke off when I tried to remove the nuts. I sprayed PB BLASTER on them every week for about a month, and today, with the help of a Craftsman stud extractor (basically a socket you attach to a breaker bar, and then slip over the stud), the studs came right out, just as Dave said they would. Sure beats drilling! (contributed by Jim Quist)
6. Paint and Rust Removal
I don't sandblast old hydrants. I leave them in the hot dip tank at the local automotive machine shop for a couple of days. They usually come out pretty clean. Then I'll polish off any little bits of paint with a fairly soft wire brush on my angle grinder. (contributed by Willis Lamm)
Sandblasting results depend on several different factors:
air pressure - high pressure removes stuff quick, but can also damage what you are cleaning (on thin metals, can warp metal not only due to the pressure, but also the heat form friction). lower pressure takes more time and blasting media, but you can get good results from it.
nozzle - the smaller the nozzle size, the more force the blasting media has (is usually dependant on media and air compressor size)
media - There are several different types of blasting "media" that one can use ...(also lots of "grit" sizes---just like sandpaper. What size to use depends on your air supply and nozzle diameter)
I usually start out with my sandblaster on a lower pressure; maybe 60 psi (pressure fed sandblaster as opposed to a siphon one) with black beauty (on cast of course, for brass stuff, I really drop the pressure down (30psi) and use sand--doesn't seem cause damage). If neither of these seem to work, then I'll use a paint stripper and let it set for a while, then hit it with the black beauty. On cast, the max pressure that I'll use is 90psi.
Some things to remember:
- USE a respirator, long sleeve shirt, pants (coveralls work good), a hood and good gloves when sandblasting with any media (actually, you are supposed to use a air supplied system when doing this stuff)
- be aware that old hydrants may have lead paint---make sure that you collect all of your spend media and dispose of properly.
- if you are blasting after using paint remover---remember that paint remover WILL destroy clothes (and pretty much everything else that it comes in contact with)
I try to avoid using paint remover---it isn't very good for the environment. As for media, I use black beauty because it has less of a health risk than sand.
Also, if you are cleaning up around the stem---use duct tape (and be careful when blasting) to keep sand out of the mechanism (sand and grease---what a wonderful way to "lock" things up)(contributed by Dave Raupach)
My hydrants all had very thick layers of paint on them. I found it relatively easy to flake the paint off using a chisel. Most times I could push the chisel by hand, and only tapped it lightly with a hammer for the tough spots. The outer layers all seemed to come off together leaving the original layer intact. Then I used paint stripper to remove the original bottom layer. It took a very long time to do but I'm sure it is the cheapest way. If the paint is not very thick. You may be able to simply rub the hydrant down with steel wool and treat what paint is on it as an undercoat. Then simply apply your new paint over it.(contributed by Stuart Niven)
Clean it as well as you can. Wire brushing is a necessary but usually not sufficient step. Blasting is the best method of surface prep. If old paint remains IT MUST BE WASHED CLEAN, preferably with hot water and detergent. I have heard good things about "liquid sand-paper" and the like but have never used them.(contributed by Carl Louie)
To remove the majority of the old paint I used the point end of a hammer to pick away at the paint. I found it is time consuming but does a great job by not wearing away at my Dewalt angle grinder or wasting sand. I use a sand blaster on the more difficult places to reach. (contributed by Michael Avila)
7. Brass Refinishing
(Although brass operating nuts and brass nozzles are painted by manufacturers and city maintenance workers most collectors cannot resist polishing these parts to show off the natural beauty of brass.)
I shine up the brass with a fairly soft wire brush on my angle grinder. (contributed by Willis Lamm)
How I restore the brass operating nut depends on how badly the brass is tarnished. If it's not too bad I just rub it down with fine steel wool and polish with regular brass polish and a cloth. If it's badly oxidized I use sandpaper (course to fine) first, and then steel wool. After the brass is all polished, I spray the operating nut with a clear coat metal finish to prevent the brass from oxidizing. The brass seems to change colour slightly as a result of the clear coat, but at least it shouldn't get worse. I have a hydrant going on two years since restoration and it looks the same as the day I sprayed it. I suppose leaving the brass natural gives it the best look and you can always keep polishing it as needed. I just found that the first thing visitors do when they see my hydrant in the living room is try to turn the operating nut with their hand. I'm sure it would have finger print marks on it, if not for the clear coat. (contributed by Stuart Niven)
I use clear lacquer from a spray can to protect the shined up brass. I let overspray go on to the bonnet from the top nut since lacquer can be painted over on the bonnet; this eliminates the need to double mask. I have had good results with lacquer. I was told that spray polyurethane would chip and peel off the brass in time. (contributed by Ed Masminster)
I was at the local Walmart picking up some brass polish to cleanup some of my old brass fire nozzle's when older man came up asking me what I was going to polish up. When I told him he came back with something very odd and strange. He said to use Grape Kool-Aid and let soak in it over night. He said it will take off the tarnish and clean up very well and that left to do is to use little polish and fine steel wool and it shine like nothing you have seen before. Well I was like "yeah right, to good to be true" so asked him how he came across this and said he was a retired Navy man and that they use to soak the brass before ship inspection and then give good wipe down with polish and very fine steel wool. So with Kool-Aid being so cheap, I picked up a few packages and gave it shot. I went home, made up gallon, and put one of the smaller nozzles that was tarnished so bad it was black in the Kool-Aid and let soak over night. Well it completely cleaned to brass such that I only had to wipe it little to get some tarnish off and it was just like washing mud off your hands. The Kool-Aid package says not to store in a metal container ...(contributed by Jason Cherry)
I have found that implement paint works well (i.e. tractor paint). It covers well as long as you do not add to much thinner, and will not chip as long as you do not add to much hardener. Implement paint comes in many colors and stands up to weather very well. The not chipping part is important if you will be moving your hydrants alot, such as in a museum.(contributed by Shane Bullock)
Prime with a high quality machinery primer. Lots of manufacturers make high quality metal primers. Paint with a high quality machinery enamel. Lots of manufacturers make high quality metal enamels. If you are not going to do a good surface prep them just wire brush off the scale and slap on the cheapest paint you can find. The paint will be no better than the surface prep. Talk to a local paint distributor. Rust-Oleum or Sherwin-Williams or the like. They will help you.(contributed by Carl Louie)
Personally, I'm stuck on Rustoleum industrial line of paints(Home Depot /
Lowes). If there is a lot of detail showing on the hydrant, I'll use the
spray version, otherwise I'll use the brush on type. As for primer, if it
is gonna be a darker colored hydrant, I use the rusty metal primer; and if a lighter
color then white/grey primer (once again, Rustoleum industrial).
I use Tremclad rust paint on my hydrants. It is thick and that
reduces drips and runs. It also flows together to reduce or eliminate
brush marks. It dries with a high gloss finish. I don't normally use
any clear coat on top of it, and leave it as is. One drawback to
Tremclad is that there are a limited number of colours available. I
have mixed colours successfully though. For example, you can add
white to dark blue to make light blue and add red to yellow to make
orange. The disadvantage to that is you won't be able to match the
colour in future for touch ups or repainting.
I wrote to 3 major paint manufacturers in the USA and they all pretty much recommended the same thing: excellent surface preparation, use of a primer, and either the waterborne industrial acrylic-latex paints or the two-part polyurethane products. Please note that my main stipulation was that the paints be highly fade resistant outdoors. The most frequent complaint I've heard from municipalities is that they don't like having to re-paint every few years.
Water departments have responded to these manufacturer's recommendations saying that while they like acrylic-latex, it is much fussier about ambient humidity; mist, dew, damp weather, etc. The problem is that acrylic-latex will never cure properly if applied under damp conditions. It is ruined. You absolutely need a dry day.
Also, a coatings professor told of one utility that painted many hydrants with high performance urethane, only to find that the paint didn't cure at all: turns out the workers used only "part one" of the two part system. Yikes. Read the label.
Here is PPG's (Pittsburgh Paint & Glass) information:
Primer: Waterborne Acrylic
PPG Pittsburgh Paints Pitt-Tech 90-712 Primer/Finish 3.0 mils dft
Topcoat: Waterborne Acrylic
PPG Pittsburgh Paints Pitt-Tech 90-Line Satin/Gloss DTM 3.0 mils dft
SSPC-SP1 solvent cleaning, [which may include]:
Low-pressure (1500 -4000 psi) high volume (3 - 5 gal/min.) water washing with appropriate cleaning chemicals is a recognized "solvent cleaning" method. All surfaces should be should be cleaned per this specification prior to using hand tools or blast equipment."
SSPC-SP7 Brush Off Blast, which is defined as:
"A method in which all oil, grease, dirt, rust scale, loose mill scale, loose rust and loose paint or coatings are removed completely. Tight mill scale and tightly-adhered rust, paint and coatings are permitted to remain. However all mill scale and rust must have been exposed to the abrasive blast pattern sufficiently to expose numerous flecks of the underlying metal fairly uniformly distributed over the entire surface."(contributed by Jim Quist)