Noob Looking to Print Delrin - Advice on Getting There

[TruNoob]

Hi all,

Not a CAD designer, not an engineer. Not illiterate with my hands or computers either. I've never had a 3D printer before and this post is asking for advice about progressing from here to printing delrin. I'm currently looking at a Prusa and am trying to learn my way around Fusion 360 before ordering.

I'm into various outdoor sports at a pretty high level and often need little custom items of gear; normally fairly simple but nothing like anybody is selling. I've been looking into 3d printing for a while as I could make use of lots of the usual PLA/PETG/ABS gubbins, but also literally save several thousand £ over a few years if i could print things like pressure proof (6-11bar external pressure, 0.4L+internal volume) canisters and some simple mounts out of Delrin/Acetal/POM. I know a lathe/mill may be a simpler/more reliable way to do this, but for various reasons that's a bit much for me.

My plan is to:
1. Learn to design simple parts
2. Buy a printer
3. Learn to print slowly PLA/PETG/ABS, and maybe a little bit of flexi material
4. Improve at 1 and 3
5. Learn to print delrin

Part 1: For about the last week I've been playing around on TinkerCad and Fusion360. I've not looked at any tutorials or anything yet, but I'm getting the basic idea of containers/boxes/nuts/bolts on the design side, though I haven't been able to figure out how to check my parts interact correctly. So I'm confident that with time and a bit of direction/focus once the printer around, I should be able to live up to simple designs I wanna print. Does this seem a reasonable approach to people? Seem like I'm on the right track?

Part 2: I've been looking at a Prusa Mk3S+ kit. I'm reasoning it seems to have a hot enough bed and nozzle for delrin, and suitable build size and tolerances for the parts I have in mind. I'd be able to build my own temperature/airflow/pressure controlled enclosure for it relatively simply. Here I've got a two questions:
1. Can I install an aftermarket bed? Do people make aftermarket heated beds and stuff? The thermostat on it might be set a little low for delrin based on my reading around. It also might not.
2. The price of the prusa is pretty, mmm. I'd pay it but it's definitely the upper end of my budget for a first printer. I want to ask about clones but I don't even know what to ask. I'm scared about losing support/community/slicer compatibility etc over time?

Parts 3, 4, and 5 should hopefully run themselves. But I'd appreciate any comments on my plan, answers to my questions, or general advice before I pull the trigger!

Thanks everyone! I hope this is the first of a few posts on here!