Using Blue Bend: a guide
Description:
Blue Bend is a water soluble, non-toxic, amorphous isomalt-glass composite used to support thin wall tube during complex or three dimensional bending operations.
The material is solid at room temperature, thick and viscous from 275°-300°F and pourable between 300°F- 340°F. Above 360°F, Blue Bend begins to overheat. Past 380°F, Blue Bend should be considered degraded and discarded.
Once fully set, tubes filled with Blue Bend can be bent in any ambient room temperature. After bending, Blue Bend can be easily melted out, recovered and reused. Any remaining residue can be dissolved in water.
Safety warnings:
Molten Blue Bend can cause serious burns. Take precautions when handling hot Blue Bend, especially when pouring or emptying. Use heat resistant gloves and eye protection at all times.
Blue Bend is non toxic and does not produce significant smoke or smell when used. However as with any high temperature material, maintain good ventilation when heating.
Never pour Blue Bend into a damp or dirty tube; dangerous steam eruptions can occur.
Using Blue Bend
Tube setup:
Tubes must be clean, completely dry, and free of scale and oxides from annealing. Loose oxides can prevent the Blue Bend from adhering to the wall and can cause bends to fail. Pickling, cleaning, and drying after annealing is recommended.
CAUTION! Any moisture left in a tube can cause a dangerous ejection of the Blue Bend when steam is created inside the tube.
Plug one side of the tube with a heat safe plug or sleeve (rubber or tapered metal stopper, silicone sleeve, heat safe metal tape, etc.) and secure the tube upright for pouring.
Melting Blue Bend:
Blue Bend is a dense viscous material and conducts heat slowly. A good heating technique will heat slowly and evenly to avoid overheating hot spots. Two options are offered below:
Microwave (1-5 blocks):
To avoid hot spots, always use 50% power or lower and use short bursts when approaching the melting temperature. Wattages vary, be careful and conservative until you understand how Blue Bend behaves in your microwave.
Place Blue Bend in an appropriate container. (ex. Pyrex glass, borosilicate beaker, silicone melting pot, etc.)
Use a reverse pyramid heating method to gradually heat to optimum pouring temperature (300°-320°F). STIR gently between each step. The following examples demonstrate the technique and will vary based on the microwave, the heating vessel, and the total volume of Blue Bend being melted.
Ex. (3-4 blocks)
5 minutes @ 50% power
2 minutes @ 50% power (repeat until the Blue Bend is half melted)
1 minute @ 50% power (repeat until all Blue Bend is melted)
30 seconds @ 50% power (repeat until desired temperature is reached)
Ex. (1-2 blocks)
3 minutes @ 50% power
30 seconds @ 50% power (repeat until all Blue Bend is melted)
15 seconds @ 30% power (repeat until desired temperature is reached)
Blue Bend is ready to pour when it reaches a fully liquid, smooth, syrup-like consistency, and there are no remaining pieces of unmelted Blue Bend in the container. The surface should be calm with no active boiling.
If foaming occurs (an indication of ambient moisture; nothing to worry about) stir gently to allow the bubbles to come to the surface and settle, then continue to stir until the surface of the Blue Bend is smooth and still.
If Blue Bend accidentally reaches high temperatures (340°-360°F) aggressive foaming can occur and may spill over the top of your container. In this case, simply stir what remains in the pot until the foaming subsides and the surface becomes still, then pour as normal. Any spills can be easily cleaned later with soap and water.
Pour into your tube and follow the cooling procedures. Remember to top off the tube once the Blue Bend shrinks.
If using a glass container, pour any remaining Blue Bend out onto a safe surface or into a silicone container. If more than ½ inch of Blue Bend cools fully in the bottom of the glass, do NOT microwave; the expanding Blue Bend will shatter the glass. Instead, heat from the outside with a soft torch until the plug can be extracted, broken, and returned to the container.
Induction or stovetop (5 or more blocks)
Induction or stovetop melting carries a higher risk of scorching, but can melt larger amounts of Blue Bend for large tubes or batch work. Given the variation in heating sources and pot conductivity, you will need to construct your heating method keeping in mind the following guidelines:
Blue Bend is a dense material which conducts heat slowly. When cooking in a pot, you must first establish a melted “buffer layer” which can be done by breaking up the Blue Bend into small pieces and arranging them in a single layer on the bottom of the pot. Turn the heat to its lowest setting, cover, and allow the Blue Bend to gently melt until the bottom of the pot is covered completely with a ¼ to ½ inch layer of melted Blue Bend. During this part of the process, you should not see any boiling or bubbling.
Once the buffer layer is established, you can add the rest of your Blue Bend, increase the heat and stir continuously until the mixture is smooth and fully melted. If melting a very large amount of Blue Bend, it’s best to add in stages rather than all at once.
It may take experimentation to develop a process that will melt the Blue Bend quickly but safely using your preferred heat source and cooking equipment. For additional help, refer to the website for video tips.
Pouring:
Blue Bend is ready to pour once all pieces are fully melted and the mixture reaches the consistency of pancake syrup or melted honey. If necessary, transfer to a pouring vessel with a spout or use a ladle to fill the prepared tube. Pour slowly to give the material a chance to reach the bottom of the tube and raise any large voids to the surface. Tubes can be warmed before or during pouring but this is not necessary except in certain cases where the tube may be especially long or small in diameter.
CAUTION! After pouring, the outside of the tube will be extremely hot; handle with appropriate safety equipment and care.
Blue Bend (as with most high temperature materials) will shrink as it cools: top off with additional Blue Bend after 5-10 minutes.
Cooling:
Blue Bend is ready to bend when the tube has cooled to room temperature throughout. Given how slowly heat travels through the material, it can be difficult to confirm the temperature of the core, especially in the case of large diameter tubes and an additional buffer time after cooling is recommended.
As an example- Given a ½ inch diameter tube, cooling and setting time is around 3-4 hours.
Cooling and set time can be shortened by fan cooling the tube after pouring.
Bending:
Blue Bend is designed to successfully support tubes in many different types of setups from freehand to machine bending. For individual help with setups or troubleshooting bending techniques, please reach out using the form on our website and we’ll do our best to help!
Emptying:
One of Blue Bend’s shining features is the ease of removal once the tube is bent.
Prepare your landing zone with a heat safe surface and either silicone containers, or a plate or bowl covered with silicone baking paper (parchment). Do not use wax paper.
Hold the bent tube with tube pliers, or hang over the surface with wire.
Using a wide soft flame, heat the tube evenly and drain the Blue Bend onto the landing zone.
Soak the now empty tube in water to dissolve any remaining residue. Soap and hot water can increase the rate of removal.
When cool, recover the Blue Bend and store in an airtight container. Discard any sticky pieces or droplets that are a different color.
Additional notes:
Blue Bend is moisture sensitive. During regular use, it will absorb and cook off atmospheric moisture in a cycle that should be stable and not affect the results of the bends. However, in extremely wet conditions or if storing uncovered for long periods of time in humid climates, Blue Bend can become waterlogged and lose some of its support capabilities. In this case, cook to 340°F and hold for 10 minutes while stirring to remove the excess moisture and the Blue Bend should return to its original state.
Revised: September 24, 2026
www.medlinhorns.com/bluebend