DIY Acrylic Tube

[OneDummHikk]

I was going to wait until I had at least one tube made before posting this thread but I ran into some things that I wanted opinions on. I will try to take pictures later today of what I have so far but its mainly just pieces.

I cut 2-22.5" circles. I then cut 1.5" x 28" slats to go on the outside of the two circles to create a jig to roll the acrylic around. That is as far as I have gotten because I am thinking about some other things that I need to figure out before assembling it.

Anybody ever tried this before? I want to take 1/4 or 3/8" acrylic, heat it, wrap it around the jig and then end glue it. Instead of simply glueing the ends together, there will be a "splice" piece that is a T shape that holds the joint together. I am also considering an I shaped piece to help hold the acrylic straight at the joint.

Think Volcano skimmers and that is precisely how they made the 24" cylinders for them.

Instead of trying to make 4' or longer tubes, I am thinking about simply making 24" sections with flanges so that I can extend/shorten it as I need to.

If I can make the 24" tube and get it to work, then I will probably make any tube over 14" since it is so expensive to buy.

The round jig will have a slot cut into it that the acrylic will slide into, then you simply wrap it around the jig while heating it. The slot will keep it in place so you don't have to try to hold it and it will help with what I call straightening where the end will tend to want to not want to curve properly.

The other end of the acrylic will fit into a clamp setup to hold it in place. The jig itself won't make a complete circle but rather a half circle. It will make about 60% of the circle to allow trimming. Then you glue the two half circles together.

I will try to get pictures today and so you can see what I am describing (hopefully).

Any/all thoughts/comments are welcome.

[OneDummHikk]

I didn't get any pictures taken but I did get the jig for a 12" tube assembled. Its glued and drying. Tomorrow I will turn it on a lathe and make it round. Then it will be time to try to make a tube. As it is, the idea is to roll it around the round jig. It will be cut as close as I can to making the complete circle, but a little short to make sure it isn't too long. Then, using a T shaped "connector", assembling the joint like this:



The red will be each end of the acrylic and the blue will be a "filler" piece. What the filler does is allow me to not have to make the ends meet exactly. I can get them close then cut a groove that the T filler will fit in. If the T ends up not strong enough of issues, I can make it an "I" shaped where it has the lip on each side but I prefer the T shaped.

[Doug1]

I saw this in the email notification Randy and I was going to ask you, doesn't acrylic need heated up in an oven to be formed like you want to do?

[OneDummHikk]

Yes. You heat it to make it soft enough to bend. What I am making won't fit in a kitchen oven (many use the kitchen oven on small pieces) although I do have a way to heat it. A "torpedo" style kerosene heater is going to be the first try. If that doesn't work, I will build an oven big enough to get it into and then add heating elements from old stoves to get it hot enough. You heat it, roll it, let it cool to hold its shape.
I got the idea from a "volcano" skimmer. If you remember the reefzilla tank, it had a volcano skimmer built by "spazz" (username on RC). It used 24" diameter tubing that was made the same way. It had a grey stripe up it that was the joint. Not sure if it used the T/I type connector or if it was simply an overlay to help strengthen the joint.

I went out today and my back started bothering me so I didn't get a lot done to the jig. I still have to make a home made lathe to spin a wooden tube that is 12" round and about 14" long. Then it will be time to make a heater

[Doug1]

Good luck, that sounds like a major project

[OneDummHikk]

For the last week or two, I have piddled with the jig to make the tubing and on my way home from Jacksonville (Drs appointment), I realized I made a major mistake. I cut a circle 22.5" in diameter and nailed strips 3/4" thick 1" wide to make a "tube" out of wood. The wooden strips were pine that I cut out of 2x6'es. So far so good, right? WRONG! When you heat acrylic to roll it, its between 350-400 degrees.

Originally, I was going to heat the acrylic, wrap it, re-heat, wrap and repeat until I got it finished. The issue is that the jig will have to go in the oven. The oven is another DIY project that isn't the issue.

When you heat pine to between 350 and 400 degrees, the pine tar in it seeps out and that is going to contaminate my acrylic

For now, I am going to try coating it with fiberglass and see if that will keep it from oozing out the face. If it still oozes out of the face, it will cause the fiberglass to separate. If it doesn't, then coating it with fiberglass will solve the problem. If it doesn't, then I have to find some other material to make the strips out of that will withstand the heat (350-400 degrees F) and not cost a fortune.