Hot Glue Stick Support Extension

Fellow maker, have you ever been in the middle of a crucial hot glue-up, squeezing out the last drop of the previous stick, while fumbling to keep a new limp 10” glue stick inserted in the back of the gun? Frustrated, I set out to find a solution to support a fresh 10” glue stick without making irreversible alterations to the hot glue gun itself. The Hot Glue Stick Support Extension that I devised has proved to be an invaluable addition! Let’s get hot and sticky!

• Hot Glue Gun (Surebonder H-270C)
• Hot Glue Sticks
• Callipers
• Appropriate Screwdriver (Phillips #2 in my case)
• Tinkercad (Free and intuitive browser-based 3D modelling software)
• Access to a 3D printer

Start by looking closely at your glue gun, especially the orifice into which the hot glue stick is inserted. After close inspection, you might notice a recess around the hot glue stick opening that appears to have no intended purpose (refer to above image). I decided to take advantage of this recess during the design process as an attachment point for the support extension. Next, CAREFULLY open up the hot glue gun (there is a spring loaded mechanism at play here ) to familiarize yourself with the different components and take some accurate measurements. A Phillips screwdriver was required to open mine up. Refer to the image notes above to discover the different components that make up most hot glue guns.

To create an accurately scaled 3D model, precise measurements are required. For this, you will need a pair of callipers and a means to document the measurements. *Expensive digital readout callipers are not necessary for this step, in fact, cheap plastic callipers are perfectly adequate. If all you have access to are rulers, using a transparent plastic one will help you make more accurate measurements.

Using the depth gauge on your callipers, measure the depth of the recess next to the hot glue stick opening (2mm in my case ). With the interior jaws of the callipers, measure the width of the recess (2mm in my case ). Then, using the exterior jaws of the callipers, measure the distance from the recess to the exterior of the hot glue stick opening (3mm in my case ).

Re-assemble the shell of the hot glue gun and use the interior jaws of the callipers to measure the hot glue stick opening (13mm in my case ). You may also want to measure the outside diameter of the raised edge surrounding the hot glue stick opening (20mm in my case ). The last measurement to document is the diameter of the glue sticks themselves (12mm). With these measurements we can start the 3D modelling process using Tinkercad!

Let’s start by using the Cylinder tool to make a ring that will fit into the recess of the hot glue stick opening at the rear of the hot glue gun. As a habit, before modifying the dimension of the cylinder, I raise the number of its sides to the maximum possible (64). Next, add the following measurements together to calculate the diameter of the recess: the depth of the recess [2mm] (x2) + the inner diameter of the hot glue stick opening [13mm]. For me, this gave me a total of 17mm. After selecting the cylinder, click and drag one of the white corner points while holding Shift (this keeps the circle square ) and adjust its size to the appropriate diameter of the recess (17mm in my case ). Now adjust the thickness of the cylinder to slightly less than the width of the recess (2.25mm in my case ).

For the main body of the support extension, use the Cylinder tool to create another cylinder that is the same diameter as the hot glue stick opening (13mm), *remember to change the number of sides of the cylinder to 64. The height of this cylinder is a personal preference; aim for a height that you believe will be enough to support a standard 10” hot glue stick, after some trial and error I settled on 64mm.

Use the Cylinder Hole tool to add a third cylinder to the workspace and make the diameter that of a standard hot glue stick, 12mm. Change the height of this cylindrical hole to something greater than that of the previous cylinder (68mm for example ).

Select all three cylinders by using the click, hold and drag selection method or by holding down Shift while selecting each piece individually. Next, use either the Align icon or the keyboard shortcut “L” to align and center all three cylinders.

Now group the three cylinders together by using either the Group icon or the keyboard shortcut “Ctrl + G”.

High five! You have just completed the simplest version of the design! Although it is perfectly functional, the walls of the main body are quite thin (1mm) and there is nothing to support the hot glue stick support extension at its base once it exits the back end of the hot glue gun. There is also no clear way of knowing how much glue is left in the support extension once the glue stick goes past its end. Think of this version as a proof of concept model. Now let’s improve and refine the design!

To make the hot glue stick support extension more robust, let's increase the wall thickness of the main body of the support extension after it leaves the end of the hot glue gun.

First, select the initial design and use either the Ungroup icon or the keyboard shortcut “Ctrl + Shift + G” to ungroup the three cylinders. Next, use the Cylinder tool to create a fourth cylinder that is slightly larger than the main body of the extension tube (14.5mm in my case ). Use the Z-axis tool (black arrow at the top of the cylinder ) to raise it the distance necessary to clear the end of the hot glue gun (6.5mm in my case ). Adjust the height of the cylinder to match the height of the previous main body piece of the support extension.

Next, let’s add some additional material to the hot glue stick support extension where it exits the hot glue gun. Use the Cylinder tool once again to create a 64-sided cylinder that is the same diameter as the raised section around the hot glue stick opening at the back of the hot glue gun (20mm in my case ). I chose to make the thickness the same as the raised section on the back of the hot glue gun, which was 2.25mm.

Now, use the Cone tool to create a cone with the same base diameter of the previous cylinder's diameter (20mm in my case ) and adjust its height to around 11mm. Bump up the number of sides of the cone to 64 like we’ve done to all the cylinders thus far. Use the Z-Axis tool to raise the cone so that it sits on top of the last raised cylinder (8.25mm in my case ).

To be able to see how much glue is left in the hot glue stick support extension, let’s create a viewing window! Start by using the Box tool to create a box that is 3mm wide x 20mm long x 36mm tall.

Then use the Round Roof tool to create a round roof section that is 3mm wide x 20mm long x 2mm tall. In an attempt to make this less confusing, let's identify this piece as RR1. Duplicate RR1 and use the Mirror tool icon or the keyboard shortcut “M” to make a vertically mirrored round roof piece that we'll identify as RR2.

Now, with RR2 on the work plane, use the Z-Axis tool to raise the box by 2mm (the height of RR2 ).

Use the Z-Axis tool again to raise RR1 to the combined height of RR2 and the box piece (38mm).

Next, select all three pieces and use the Align tool to align them, then use the Group tool to group them together. The last step is to transform this new window shape into a Hole and use the Z-Axis tool to raise it to an appropriate height for it to act as a viewing window in the side of the support extension (16mm in my case ).

Finally, select all of the pieces within the work plane (minus the window piece ), center them all with the Align tool and then group them all together with the Group tool. Next, align the window piece with the main body of the support extension with the Align tool and group the two pieces together with the Group tool.

Congrats! You now have a refined design that in theory should be more robust and practical! Export your design as an .obj or .stl file!

Import your 3D file into your preferred slicing software (Cura in my case ) to prepare it for 3D printing. Depending on the capabilities of your 3D printer, print the design using a robust filament such as, ABS, PETG or Nylon. Don’t fret if you can only print your design in PLA, after testing the different variants of the 3D printed design, I’ve found that PLA holds its own if not abused. I settled on using white PLA for my final print as the colour matches the hot glue gun that I’m using.

I used medium print settings with 100% infill. If you don't own a 3D printer, check your local library or maker space for access to one!

Insert the freshly printed hot glue stick support extension into the end of the hot glue gun and close up the shell. Re-insert the front support and load up your hot glue gun with a fresh 10” hot glue stick! The final result has far surpassed my initial expectations during normal quotidian use and after having made this simple modification, I am dumbfounded as to how this isn’t already a standard feature on every hot glue gun!

With how well the hot glue stick support extension modification went, I started to look at what other simple improvements could be made to my hot glue gun. After using the hot glue gun regularly on nearly every project, I’ve come to realize that I find the trigger mechanism to be uncomfortable to use for extended periods. The problem is that the plastic support piece under the trigger doesn’t allow for your ring and pinkie fingers to rest comfortably around the grip.

The quick and easy fix was to use the grip of the hot glue gun as a guide to draw a line on the trigger outlining where it meets up with the main body and use it to hog off the surplus material with a bandsaw. After a bit of sanding to smooth out the rough edges left by the bandsaw, I re-installed the trigger mechanism and was amazed at how much it improved the ergonomics of the hot glue gun.

I hope you found this Instructable useful and decide to make these simple modifications to your own hot glue gun! Who knows, maybe manufacturers will eventually catch wind of them and start to include these design improvements as standard features. Use this also as inspiration to take a second look at the objects you use every day and see how you can improve them!

Cheers!

Mr. Ham