The title of this month’s SHOP TALK may be a little deceiving as the work shown did not exactly take place over one weekend, but the timeframe was something close to that, and the one-man aspect is truly accurate.
So, let’s take a look at a project that I intentionally configured to make it easy for one man to construct, done in components mostly of lightweight aluminum, and designed for easy step-by-step assembly in the field.
The “billboard” was really just an all-metal sign that would go at the end of a football field at a nearby high school stadium. The face size was to be 6’ x 12’ in three sections, and the frame or construction of the sign was totally up to me.
I knew that I would build it myself, and install it myself, as right now labor at the sign shop is in short supply. And it indeed would be constructed over a long Saturday, and ready for the powder coating shop on Monday morning.
So, keeping the items light, easy to put together with just two hands, and in small components really were important aspects of this shop-made puzzle. What I needed for the upper frame unit was an aluminum extrusion which, though it might exist, I did not have on hand or quick access to one.
So, the “extrusion” was made by putting two sizes of light wall aluminum tubing together to make a picture frame extrusion 3.75” wide with a recess 1.25” wide to set the face sections into. It was made by securing 1.25” x 1.25” x .080 wall to tubing 2.5” x 2.5” x .080 wall thickness. Short and long lengths for the rectangular shape of the frame were secured together with a number of flathead countersunk screws.
Pieces of this new “extrusion” needed to be mitered very accurately so the frame would go together like a picture frame, with close fitting joints. We have a fairly good quality metal bandsaw that would make quick work of this cutting job, but it is not truly accurate for making mitered cuts that are a perfect 45 degrees, and cut true all the way through.
A regular carpenter’s miter is more accurate and will make good fitting joints. Fortunately, this type of wood cutting saw can also cut soft aluminum tubing using a fairly fine-tooth carbide tipped blade. That type of tool, a fairly inexpensive one, was used to good effect for this project and the joints were on the money.
To hold the four frame members together I needed small brackets or fittings, cut from .090 flat stock aluminum, and larger “C-shaped” brackets that would attach the top and bottom frame members to the posts. These fittings were cut on a CNC waterjet, and some of them had to be formed in a sheet metal brake to make triangle-shaped fittings for the vertical stringers, and also to make short aluminum angle pieces as attachment fittings for the large “C-shaped” brackets.
Also, several special fittings were made of steel to be used to make the two-part posts telescope easily together. The main part of each post was made from a 12’ section of 4” x 4” x 3/16” steel tubing that would be set in concrete and reach approximately 9’ above the ground. These two posts were made from one piece of steel tubing 24ft long.
The upper section of each post was made from 2½” square steel tubing, which would slide into the larger tubing. By making the posts sectional, kept them light and easy to work with for one man, and allow the parts to fit easily in an oven for powder coating. Small square bushings made of 1/8” steel sheet provided the proper telescoping fit and a cap over the larger tubing.
After all parts were made, they were taken to the powder coating shop where they would be coated to a nice glossy maroon. The aluminum “extrusion” parts, the brackets and fittings, and both two-piece posts were coated at the same time on two racks. This durable powder coated finish will protect the parts from rust and corrosion and it is very likely they will outlast this old sign maker.
Out in the field, once more I got my upper body workout by digging post holes by hand and setting the lower half of the two-part posts in concrete. Care was taken to not only get them level, but get the tops of the posts on the same plane as well.
After the concrete was set, the next day the component construction began by dropping the upper post sections in place. They fit snuggly but not tight, and needed no fasteners to hold them in place. The next step was to put the top main “C-shaped” brackets in place at the top of the posts, and then secure the top picture frame member perfectly centered.
Everything else would hang off these brackets until the other three sides of the picture frame were put together, and then the lower “C-shaped” brackets were put along the bottom of the frame, and were attached to the frame and the posts with both rivets and screws. Some “serious” self tapping screws were used to hold top and bottom main brackets to the posts.
These steps did not take long, no welding was required, and the frame members fit together just like they did in the shop. I forgot to check the frame for squareness before it was attached to the posts, but the tight fitting mitered corners must have trued things up since the finished frame was fine.
The vertical members, made of more 1.25” x 1.25” tubing, were secured using our formed triangle shaped brackets, and this was the last step before installing the faces.
For one man, getting the first sign panel perfectly vertical and perfectly centered can be a bit of a chore, since holding a part exactly in place and using a screw gun at the same time may require three hands. But with some effort the work can be done with just two, and the trick is to get the center one exactly right, and then work left and right. Quickly I did the drilling, riveting and touch up painting, and I was really motivated because a junior high football game was starting over my shoulder as I worked.
Fortunately, I had allowed ¼” to 3/8” extra space in the frame so the fit did not have to be unmanageably perfect, and the faces, which had been graphically completed by my crew back at the shop, went together with very tight fitting seams.
This was a fun job, and was truly a one-man parade. But I enjoy things like that and the design of two-piece posts, the light weight “extruded” aluminum frame -- and simple shop-made hardware, all prefinished at the powder coating shop -- made the construction a simple “tinker toy” procedure. If you have a job like this one to build, especially if you work alone or with little help, the construction methods used for this basic sign job are ideal for a one man crew, and may be worth considering for your next project. |
