Surely you scenic types are familiar with the use of concrete form tubes for creating columns and pillars and pedestals and the like. I just wanted to share what we did for our current production of ALICE IN WONDERLAND, because I didn't find it in my forum searches.
The main problem with these tubes always arises when one must combine 4' sections to create taller columns. Not only is it tricky to fuse them -- they are cardboard, after all -- but it's also difficult to match them up, since they often vary as much as a half-inch from their advertised diameter, are not perfectly round, and normally were cut at a slight angle and thus do not have an edge perpendicular to their length.
So, after about half an hour of pulling them off the shelf at Home Depot and matching diameters as best I could, I began mulling over ways to join groups of three four-footers into 12-foot columns that were reasonably straight and plumb. The answer: buy an extra tube that matches the diameter of each group.
We cut the extra tube into 1-foot segments, then sliced the segments along their length on the table saw, making them into self-compressing couplings. We then rolled one of the cut edges inside the other so that we could slide it into the end of another tube. Once we were sure it would fit and compress itself along the inside of the other tube, we pulled the coupling out, coated half of it with Liquid Nails, and pushed it back in. At this stage, we hurriedly made sure that the coupling was, in fact, properly seated and compressed along the inside of the tube, and then let it set overnight. Once the glue set, we were able to attach a second tube to the exposed end of the coupling in the same way, and also install a coupling in one end of the third tube. 24 more hours later, it was time to attach the third tube. It took two days to glue, cure, and assemble in this fashion.
It's very important that you buy one extra matching tube for EACH group of tubes; we tried to make all four couplings from one tube, and we discovered that the couplings were a little small for the second group of tubes. You'll end up wasting a bit of the tubing, but they're not expensive, and you can always find another use for the offcuts.
Apologies if this method was already discussed elsewhere. It's pretty simple, and yet it took a brainstorming session to come up with the same technique that fourth-graders use to make super-long soda straws. Maybe that says the wrong thing about me...
I'll post some photos of the finished product; didn't take any during assembly, I'm afraid.
The main problem with these tubes always arises when one must combine 4' sections to create taller columns. Not only is it tricky to fuse them -- they are cardboard, after all -- but it's also difficult to match them up, since they often vary as much as a half-inch from their advertised diameter, are not perfectly round, and normally were cut at a slight angle and thus do not have an edge perpendicular to their length.
So, after about half an hour of pulling them off the shelf at Home Depot and matching diameters as best I could, I began mulling over ways to join groups of three four-footers into 12-foot columns that were reasonably straight and plumb. The answer: buy an extra tube that matches the diameter of each group.
We cut the extra tube into 1-foot segments, then sliced the segments along their length on the table saw, making them into self-compressing couplings. We then rolled one of the cut edges inside the other so that we could slide it into the end of another tube. Once we were sure it would fit and compress itself along the inside of the other tube, we pulled the coupling out, coated half of it with Liquid Nails, and pushed it back in. At this stage, we hurriedly made sure that the coupling was, in fact, properly seated and compressed along the inside of the tube, and then let it set overnight. Once the glue set, we were able to attach a second tube to the exposed end of the coupling in the same way, and also install a coupling in one end of the third tube. 24 more hours later, it was time to attach the third tube. It took two days to glue, cure, and assemble in this fashion.
It's very important that you buy one extra matching tube for EACH group of tubes; we tried to make all four couplings from one tube, and we discovered that the couplings were a little small for the second group of tubes. You'll end up wasting a bit of the tubing, but they're not expensive, and you can always find another use for the offcuts.
Apologies if this method was already discussed elsewhere. It's pretty simple, and yet it took a brainstorming session to come up with the same technique that fourth-graders use to make super-long soda straws. Maybe that says the wrong thing about me...
I'll post some photos of the finished product; didn't take any during assembly, I'm afraid.
