Caulking gun manual injection tool


I have been thinking of ways to experiment with injection before investing in making a full-sized injection machine. Wondering if anyone has heard of or made an injection tool that would be similar to this:

– has a metal tube which shredded plastic can be loaded into and then the tube can be heated in the oven, liquifying the plastic
– then the tube can be put in a gun such as a caulking gun (user wears gloves) and when squeezed, the melted plastic will come out of the nozzle (need a metal nozzle)
– so it’s basically a large hot glue gun

Anyone played around with anything like this before? Am concerned that the squeezing part of the caulking gun can’t supply enough pressure to push the plastic out…


I would be skeptical. I think the hot glue gun works because the piston (glue rod) diameter is small and moderate force creates decent pressure. Also I think the hot glue material has lower viscosity when liquid than something like HDPE. There was a post about a handheld extruder that was motor driven.

Using the oven heating makes it hard to know when all is melted and ready to inject. Also the fumes need to be considered.

If you try this approach, post your results, it will be new data for the forum.

I realize resources are different around the world but I was able to build a desktop injector for about $100 in parts (  ). Depending on what you have available locally you may be able to reduce it further ($30?) to just the two controllers and heaters.

Good luck