Minimum viable precision heating (800F/425C)

[maker_bkquhasb_1663499851]

While I can work with most devices OK; I'm fairly novice when it comes to heating applications. I have been trying to plan a project for a while now which involves melting various plastics for molds. For the melting chamber I am just shocked at the variety of options at play here.

- Different techniques for making heating elements
- Different materials for making heating elements
- Methods for making evenly spread heat over the melting chamber
- Different materials for making the melting chamber
- Methods and/or circuits for stepping heat to discreet temperatures

Each of these have so much variety in the marketplace, it seems I need a coherent design to target before I can really compare different components -- but I don't have the understanding to make such a design.

Especially I'm trying to keep the system as simple and durable as possible without sacrificing the ability to fine tune the temperature and target different types of plastic. Any advice on any aspects of this goal is appreciated.

 

[kellys_eye]

I reckon the key to it will be 'mass' - in terms of larger blocks to maintain a given heat level or a smaller block to give faster control over it! Either way, it's all a matter of compromise and will depend on the end product/process.

Control is fairly straightforward both in application and accomplishment but the rest may be trial and error unless you're using a proven method - the approach I'd recommend anyway to avoid recreating the wheel.

 

[maker_bkquhasb_1663499851]

I reckon the key to it will be 'mass' - in terms of larger blocks to maintain a given heat level or a smaller block to give faster control over it! Either way, it's all a matter of compromise and will depend on the end product/process.

Control is fairly straightforward both in application and accomplishment but the rest may be trial and error unless you're using a proven method - the approach I'd recommend anyway to avoid recreating the wheel.

Thanks appreciate the response; just saw this notification. Yeah that makes sense.
For reference, I expect ~11 lbs | 5 kg max load and about a quarter of that for a normal load, with no particular rush on the melt time.

Blocks however will be run through a process making the plastic into either long thin strips or many small chips. Bucket materials available on hand are copper, brass, tin and steel though still shopping around for what works best using different methods. So many variations it is still difficult to narrow down which path will keep things durable and maintainable.

When it comes to the control; I'm plenty confident in being able to translate thermocouples to temperature display and similarly should have no problem varying the current going into the heating circuits. Though I suspect that approach will be too naive without some domain-specific knowledge on heating elements.

Taking this project very slow; but if I figure out enough to get a proof-of-concept; plans and control code will get posted on GitHub under Apache license - I will post a link back here in case you end up with any interest. Thanks for the feedback.