Different ways to heat

besides using a band heater what other ways can I heat my barrel ? I can only find band heaters on eBay but was wondering if there’s other ways.

Should be possible to use the heater from a watercooker with different electronics?
Also I am thinking of a solar concentrator…

@mvenson , Sorry that thread meanders a bit. I used it as a collection of ideas rather than a description of a point design.

The particular post (22/03/19) where I used the aluminum tube as a compression mold was an experiment to see how well the aluminum tube would distribute the heat from a single clamped-on cartridge heater and to see how well the arbor press could be used for compression molding. It worked well so I ended up using it in my current version show in the 06/05/19 post. I used the cartridge heaters because I had them, and I had the aluminum tube. Since they are cheap (I just bought a bunch for a couple of dollars each) I plan to use them for other things like heated molds etc.

I have not built an extrusion machine but, for that, getting a good dimensional match between the tube and the auger is important. I would stick with the steel tube and band heaters. I’m not sure what you mean by aluminum tube and steel pipe as barrel but directly heating the steel barrel  should work well.

S2019 I see that makes sense. I was looking at your thread posts but I was a tad lost (I’m a beginner). So for your injection you used aluminum pipe for the mold? I wasn’t sure how that worked. An idea I have, can I use an aluminum tube with a steel pipe as the extruder barrel. Since the aluminum heats up faster with the cartridge heater. Would it heat the barrel pipe better than using band heaters?

If you are using the typical threaded tip thermocouple sensor that comes with a lot of the PID/SSR/Thermocouple bundles, a convenient way to mount those, especially on a relatively thin walled tube, is to use a small block with a through hole tapped for the thermocouple thread and a couple of mounting holes or a hose clamp to mount the block. This way you thread the TC sensor into the block until the tip is pressed against exterior of your tube. You can see an example in the thread I linked.

So what S2019 is also what i am doing on my second version of my filament maker dubed FilaFactory. in this video i show the testbench. it is a little beat up but you can see that i have 2 40 watt heaters with holes drilled and them put inside the holes. Also be sure to have a hole for a thermisistor or thermocouple. Also you need 2 small holes right next to the heater cartridges and then tap for small pan head screws to hold the heater cartridges in. I did not do that on my testbench here.
https://www.youtube.com/watch?v=-4ELb3uyVSI

You can see the approach I took for both the heater and the temp sensor  in this thread http://onearmy.world/community/forums/topic/portable-desktop-injection-machine/page/3/ . Using aluminum for the barrel makes the cartridge heater more effective.

how could I secure either a cartridge or water heater? would I still be able to attach the temp control wires?

For my injector I use cartridge heaters (also called mold heaters) but it means a modified design. Amazon should have the band heaters as well.