subject: How To Block Light In Your Silicone Rubber Tubing [print this page] Silicone is frequently used for tubing because it is a durable, flexible material with a number of uses.
Some of the most common applications include automobiles, aquariums, medical-devices and scientific research.
Its resistance to heat and chemicals make it perfect for uses such as these.
However, silicone tubing is usually translucent so natural and artificial light may affect whatever your silicone tubing contains.
To this end, it is wise to take steps to block light from getting your tubing by making it impermeable to light.
First work out how thick and large your silicone tubing needs to be. As a general rule, the tubes outer diameter should be about twice the inner diameter.
For example, silicone tubing with an inner diameter of 1/8 inch must be at least 1/4 inch wide on the outside.
You should also make sure oxidation is not the problem. Moulded silicone rubber seals used in Agriculture are more permeable to gases than plastic tubing, which means oxygen can easily get through the tube, which may react with certain fluids.
So sometimes, your problem is oxygen and not the light. If this is the case, consider using temperature resistant plastics and not silicone.
Try and get the least transparent silicone tubing you can so minimum modification is required.
The majority of silicone tubing is transparent, but has different levels of colour and translucence to make it easier for you.
Deep coloured silicone tubing, which is not see-through, will block the majority of incoming light.
You can also invest in UV-resistant silicone to block UV rays.
A blue silicone tube is often used in airlines of aquariums, which blocks over 90 per cent of visible and UV light.
Then, wrap a couple of layers of aluminum foil around the silicone tube. 1/4-inch-wide tube, need a rectangular strip, 2 inches wide and 12 inches long, and carefully wrap it around the tube.
Adjust the width of the strip in proportion to the size of your silicone tube. Once you are finished, check the foil for gaps.
This method should work well even where little light could damage affect the contents of the tubing.
The downside, however, is that aluminum foil is delicate and silicone tubing moving continuously may not be able to support it.
Make sure that when you attach your silicone tubing to your apparatus, you take note of small gaps in the aluminum foil.
Next, wrap some tape around the foil to make more durable.
If possible your black electric insulation tape, especially if the tube is exposed to high temperatures.
You dont have to cover the entire tube with the tape, just two or three times every four to six inches.
If this method doesnt work for you, try painting the tubing. First apply paint thinner, which alters both the surface texture and plasticity of the tube.
Two layers of black latex paint will suffice. The first layer should be dried thoroughly before painting on the second.
You should not be able to see the original colour of the tubing under the paint.
The paint also provides a barrier to reduce oxidation.
