Recently I was tasked with restoring a couple of old cast iron garden benches and two cast iron garden chairs. All of the items had spent years in the outdoors and the wood had begun to weaken and rot. You could not sit in any of them without cracking the wood.

Restoring Castiron Chairs

I decided to start with the two chairs which were in pieces. If you start a project like this and

determine that the wood is still in good shape, you can restore the original wood just using a belt  or palm sander. However, after examining all of the outdoor furniture, I determined that the slats were too far gone to save and I would need to purchase new pressure treated wood for everything.

I needed several new 1 x 3’s at a length of 4 ft. That type of wood is only sold in 8 ft lengths so that worked out perfectly.

Unfortunately, wood of this size cannot be easily purchased as pressure treated. I knew it could be ordered, but I did not want to wait. I could have used a wood like cedar, but I opted for the cheapest option which was regular wood. Once it was completed, I would stain and seal it from the elements.

Credit: mjpyro

Since most of the hardware on the cast iron pieces were beyond repair or rusted in place, I needed some stainless steel 1 ½ inch bolts, with corresponding stainless steel nuts and washers to secure the slat boards in place.

After, a quick trip to Lowe’s, I purchased enough hardware to do all four pieces of garden furniture, along with 15 pieces of 8 ft, 1x3 standard wood boards.

The only tools that would be needed for this project were a Phillips head screw driver, two pairs of vice grips, a power drill and bit and a circular saw. The pieces of wood are so thin that you can get by with a hand saw, but your cuts will be straighter if you use a power saw.

I had everything I needed and it was time to get to work.

The two chairs went relatively quickly and only involved a couple of intricate cuts for the cast iron backing. However, I made quick work of them and had them completed in about 2 hours and ready to stain.

Credit: mjpyro

I was able to use the original hardware on one of the chairs. However, the second chair needed new nuts and bolts. After I stained them, they looked good as new.

Credit: mjpyro

Restoring a Garden Bench

I did not start to disassemble each bench until I begin to work on that particular one, and I suggest you do the same if you have multiple pieces to rebuild.

When they are still assembled, it is easier to remove a slat one at a time and measure it and

locate the bolt holes for that particular slat area. Cast iron is not exact, so you should not make one template slat to use for all of them.

For instance, if you pull off one slat, cut a replacement from new wood, then drill out the bolt holes, do not use that new piece of wood to make the additional slats. The bolt holes are likely to be off.

I begin my project with one of the garden benches. Disassembling these old benches turned out to be time consuming because the nuts were rusted on the bolts. The Phillips heads on the bolts were already stripped, so the only way to remove nuts in this situation is to lock vice grips on the nut and another pair of vice grips on the head of the bolt and turn it. All of the nuts eventually came loose using this method.

The first garden bench I worked on did not have a molded cast iron backing so it was much easier to rebuild. There were five four foot slats across the seating area, and three 4 foot slats across the back. Cutting my 8 foot 1x3’s in half was not a problem.

However, the next issue was locating the correct place in each slat to drill ¼ inch hole for the bolts.

I removed the three rotted back pieces and laid them in order on the ground so I would know which one was the top, middle and bottom slat. I then took the top rotted slat and laid it on the new cut slat and made a mark through the bolt hole with my screwdriver into the new wood. I did that on each side while the old piece was on top of the new piece. Then I removed the old piece of wood, and drilled it through. I replaced each back slat one at a time using this same method.

Credit: mjpyro

The other reason why you want to leave all of the old boards in place is that if you remove them all at once, the two cast iron side pieces will fall to the ground. Leaving them standing makes it much easier to work with.

Each slat slid through a small opening in the cast iron and was secured in place with a nut and bolt.With the back slats in place, I then flipped the bench over and removed all five of the seating slats, making sure to keep them in order on the ground from front to back according to where they were on the garden bench.I cut three 8 foot long 1x3's in half which gave me six half pieces, one more than I needed. Next, I match up each slat with its corresponding rotted slat and marked the drill holes for each.

After that, it was simply a matter of threading the bolts and securing them with washers and nuts. The washers are critical because the cast iron bolt hole are close to being the same size as the nuts. Without the washers, they once side of the nut would slip through the hole as you tightened it into place.

This is what it looked like after I applied a stain and sealer with a rag.

I had one last bench to rebuild and it was a little more tricky because it had a cast iron insert for the backing along with a curved piece of wood on the top of the back.

Second Cast Iron Bench

This bench was more involved. As you can see, there is a cast iron mold in the back which I had to work around. Also, notice the missing top piece. It was originally a curved piece of wood, but I had to improvise when I got to that point. Did I mention all of that cast iron weighed a ton?

I started out by completely removing the back and working on it first. As you can see in the shot below, some of the nuts were stubborn once again, so I had to pry them off with two sets of vice grips. Once I got one side off, I simply twisted the slat to break the other end off.

I placed the bottom piece on first as a dry run, then removed it. I cut the other pieces and attached them to the cast iron backing in my separate work area on the back of my John Deer Gator. It was easier to screw the

The top piece was a bit tricky. As I mentioned, it was originally a curved piece of wood that hugged the top of the cast iron. However, I did not have the original piece of wood to draw a template of it on a larger piece of new wood to cut it out. So I had to improvise.

I cut two pieces that met in the middle and mitered the ends so they fit together. There was no way I could have them hug the cast iron, but that was the best it was going to get. I secured them in place with screws in the back and bolts through the front.

After the back was set in place, I could remove the five seating slats and replace them one by one making sure to match each bolt hole in the new slat with the appropriate old slat for the area.Lastly, there was a thin piece of cast iron that attached to the bottom of the seating slats to give it more support. I flipped the bench over and placed it in the center of the bench and secured it with stainless steel screws.The only thing that was left to do was give it a quick sanding to remove the rough edges and make sure the wood markings didn't show through, and then stain and seal it, and give it a new home.

 

Restoring a Cast Iron Bench

Removing Rust from Cast Iron

There was no rust on the cast iron ends of any of the furniture I rebuilt so this step was not necessary in my situation.

However, if you want to clean any rust off of the ends, you can use an angle grinder or simply a steel brush to scrub it free.

A great natural way to remove rust is to sprinkle some salt on the rusted areas, then add lime juice over the salt until it is soaked. Leave it alone for 3 – 4 hours, then scrub it lightly with a steel brush to remove residue.

Summary

These rebuilds turned out great. I refurbished two chairs and two garden benches for about $35 total. Keep in mind that a similar garden bench purchased at a place like Lowe's or Home Depot is about $149.

So if you have any of these old rotting cast iron benches in your yard, they can be rebuilt with relatively little time and effort, and almost no money.