Arches support

[Frank Farmer]

I made two 20' arches for Christmas last years out of 2" grey electrical conduit. Each end of the conduit sticks about 2 feet into a 6 foot pipe pounded 4 feet into the ground. The arches held in place for over a month and then the top started to bend over. Since I only had a couple of weeks left to go, I just ran some light rope to hold it into place.

My question is, has anyone tried anything internal to the pipes to help hold them in place? Anybody tried expanding foam or cement? I don't want to fail where other's have failed before. Anyone successful?




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[Anthony in Houston]

From the picture I see that you have a very wide drive to span. It looks to be about 22 foot just guessing. Anything you add to the inside of the pipe will increase the drop due to additional weight. Foam will do nothing to help you. I have a wide drive and I am building arches to go over it. I played around with an arch but I increased the length to give me more of an arch that you have. This allows the structure to support the weight in the middle better because of the increased angle which made it more of a true semi circle.

I changed my design to have the PVC come to a point in the middle of the drive and then used straight lengths of pipe coming down to upright poles. I did this to increase the clearance over the trucks and to be able to hang items in the middle centered over the drive.

Here is an idea that should help you without making any changes to what you have.

Pick a height off the ground on each end of the arch that will give you plenty of clearance for people and cars or anything your kids can throw at it. From that point secure an eyelet to each side. Take a steel cable and secure one end to an eyelet and run it to the other side. At this point you can either use a turnbuckle or just put the cable through the eyelet and pull it tight and fasten it with a cable clamp. I would use the turnbuckle so I could adjust for stretch if needed. You will not need much tension on this to get your arch to stand up.

This setup will apply tension to the arch and make the center rise up. You may find that you will have to move the anchors closer when you do this.

You could move the arch closer together at the ground and also use a longer steel pipe driven into the ground. This will also help support your arch. Looking at your photo you can see the arch starting to bend very close to the ground. This is due to a large amount of weight from the lights and the pipe.

To really stabilize your arches you can do the cable in the center and then string the arches together on both sides and braced to the ground and or the house.

I am going to use the cable and will attach it about seven feet off the ground and then string all of my arches together.

Anthony

[Frank Farmer]

Thanks for those ideas.

Has anyone used metal fence pipe to make an Arch?

[Max-Paul]

I would think that a metal fence pipe would be great as far as holding the proper shape. My only thought is that if it was me, I would give the pipe a good paint job. Reason is that metal conducts, unlike PVC. Now I am german and have a tendency to over engineer, but this is what I would do.

As for the bending. Move the cars out of the driveway. Get a piece of that chalk that kids use on sidewalks and lay out the curve you want. See if you got a buddy that has a conduit bender large enough to handle the size pipe you are using. Might need a longer pipe / handle in the bender and be sure you have enough Arse to pull the bender. Bend a little and lay the pipe on the chalk like. Take note and bend some more. From my experience, if you over bend, you can pull some of the bend back out, but it is a bugger to do so.

Good luck and please post pix if this is the route you take.

Max