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16 October 2010
Author: Giorgos Lazaridis
Acrylic Glass Folding Heater

Worklog - The Acrylic Glass base (November 5 2010)

The rectangular tubes, 4 L 8mm quick-joins, 2 8 to 10mm Y quick-joins, a 8mm hose (i also habe 10mm hose), drills and taps...

Now i need something where the acrylic glass will stand. This something, must not burn under the heat of the lamp, nor must it become hot. If it gets hot, then the material that touches it will melt on it and the surface will be ruined.

I thought of plenty different thermal isolating materials, yet all had a flaw. For example, wood is a nice thermal isolator, but on the other hand it burns also nicely under heat... Ytong blocks are also perfect thermal isolators, but i am not building a house. Other materials had also good characteristics, but the price was not so good.

So, i turned once more to the original idea of water cooling. Two rectangular profile aluminums with closed ends will be placed above the lamp. Within these aluminums there will me constant water flow. Thankfully, water has a huge thermal capacity. Its enough to know that the energy that needs to be provided to 1 liter of water in order to be fully evaporated, is also enough to sent a batch of people to the moon with an electric elevator (the rope weight is not to be taken into account :) ).

Nevertheless, there will be a time that the water will also be hot, even if i have 2 or 3 liters of it. So, i will need something to cool the water in the tank that returns from the two bases. But that is another thing that i still think of, but i first need to run some experiments in real life. So, to make the base:The Acrylic Glass bases: (as always, click to enlarge)

 I begun by cutting a 1 meter long 15x15mm rectangular aluminum profile into 2 pieces Then, i cut 4 pieces of aluminum, 15 by 50mm to close the ends of the 2 pieces I drilled 1 hole on each of these pieces (that was not really necessary) The JB Weld. I hope that this will hold I mixed the 2 chemicals together I put a good amount of JB weld inside the rube and on the surface of the covers I used paper tape to hold the covers onto the tube for curing Did the same for the 2 tubes. Then i let them cure (with the closed side downwards) for a day

The next day, the JB Weld was 100% cured. Then, i repeated the same procedure for both tubes, but on their other side. I left them again for another day to cure. The next day, this was the result:

Hopefully this will hold.

JB Weld is not so strong after all

Don't try this at home, nor anywhere else, for it will fail. I don't know why, but i do know that the weld of JB Weld failed to hold the two aluminum parts together. I was completely disappointed by the product, as in their site they tell that it is absolutely suitable for aluminum. Well, it is not:

JB weld left me a broken connection, a broken heart, and enough mess to clear from inside the tubes, so that i wan re-use them...

Change of plan - Move to plan B

JBW may not me so strong to hold the aluminum pieces together, but believe me, it is strong enough to close the hole of the rectangular tube. I easily removed all 4 pieces from the tubes, but removing the JB weld from inside the tube was a hard job. So what? I thought that i could use this characteristic!

First of all, i closed again (with JB Weld) the tube that i tried to remove the epoxy, again with JB Weld. Then, i decided to change the topology of the inlets and outlets:

 Removing the aluminum pieces from the sides of the rectangular tubes was (unfortunately) too easy No problem though. Plan B. I will remove all aluminum pieces, but i will keep the epoxy as sealing I marked, drilled and made threads to one side of the rectangular tube I put some extra sealing teflon, because the profile has only 1.5mm thickness I'm sure the sealing will be perfect, what i' m afraid of is the mechanical endurance of the joint I put one L 8mm quick-joint on each side of the tube. These are the inlets and outlets

I feel confident about the sealing of these tubes, but i an not quite sure that they are mechanically durable. I feel like there will be no problem, i'm not sure though. Time will tell. I will keep this as-is and go to the next step...