looking for a machine capable of cutting solid polycarbonate sheets 1-5mm

[DiTBho]

today I completed the third component and smoothed the other two
They fit perfectly and they are very easy to install in the Ergopower!

Next step ... to complete my experiment I will have to prepare a steel ring.
This is where things get difficult. We will see ...

Anyway, these gray parts were made with the tools in the photos.
While the round parts were made with the help of the drill press and a screw.
To spin the piece, and use the file to give it a round shape.

I used a wooden angle (90 degrees) to help me hold the file perpendicular to the piece.

With a (mini-)lathe you could do much, much sooner 

[DiTBho]

You might consider getting the 3D scanner and a 3D printer first, then use that to print a prototype part.
After you are sure it works, send it out for someone else to make.

The cost for someone else to make these parts for you will not be that high, here is a US example, I'm sure there are many in the UK: https://sendcutsend.com/

thanks for this idea!
I re-think about this, and I think I will use this very service, cutting or laser, or CNC, done by a service.
To make the case of a very complicated piece of equipment.
Let's see what they ask me for qty=5 pieces!

[fourfathom]

Let me again mention the Shapeoko CNC mill.  Having no serious prior mechanical experience beyond using a drill press and hand tools, It took me a while to get comfortable with it.  But now I find it very handy, and use it for all sorts of things -- street-number sign in wood, engraving aluminum, milling aluminum front-panels (holes and recesses), HDPE fixturing to help with other jobs, etc.  Once you get it set up you can quickly run off many copies of an item (if you so choose), and even doing one-off work goes pretty quickly.  This is an X/Y/Z-axis machine, so some shapes are easier than others.

The Shapeoko is a mid-range unit, using belts for X and Y, and a lead-screw for the Z axis.  All are driven by servos, and it's rigid enough for my needs.  If you are only going to work with plastic you can probably find a less expensive machine.

[wraper]

For laser cutting you should use either acrylic or polystyrene sheets.

Never used, but ... very interesting, even though I don't really like that they are transparent, I could always cover them with paint 

You can buy any color you want. Also cast acrylic can have matte finish too.

[5U4GB]

I've never owned one, I've always wanted one
is there any "micro" trim router?

A standard trim router is about as small as they get, any smaller and you've got something like a Dremel which won't be up to cutting much without risking burning out the motor.

When you get one, two things to look for is soft-start so it doesn't kick when you switch it on as all the cheaper ones do, and variable-speed so you don't burn up your workpiece if you're cutting plastic or similar.  Most of the cheapies have neither.  The go-to one for this is the Makita RT070x series, you can either buy a genuine Makita ($$$) and then get any accessories you want from Aliexpress because this is the one that everyone copies (search "electric trimmer" on Aliexpress and you'll get an awful lot of very Makita-looking routers), or get the entire thing from Aliexpress if you don't want to pay Makita prices.  In that case just make sure you get a slightly more expensive one that advertises variable speed and soft-start.

If you want to do more than a few pieces with this setup you might consider making a router table which allows you to move the workpiece rather than the router, check out some Youtube videos for how these are used.

[artag]

You should not cut PC with laser. Not because of toxic fumes but because the result will be awful. For laser cutting you should use either acrylic or polystyrene sheets.

Having tried to do this, I can confirm that the cut edges (which took forever) were browned and nasty.

[rdl]

Filing out a big rectangular hole in plastic is always slow with poor results. I did this in about 30 minutes on a little Proxxon mill. First time I ever used it so I was probably slow. I thought about going back and cleaning it up a bit, but decided the first rough cut was good enough.


(click for bigger)

[tszaboo]

Have you tried a nibbler? Or if you want to be cheap a nibbler attachment to a drill.

[DiTBho]

Filing out a big rectangular hole in plastic is always slow with poor results. I did this in about 30 minutes on a little Proxxon mill. First time I ever used it so I was probably slow. I thought about going back and cleaning it up a bit, but decided the first rough cut was good enough.

Like this one? (MF-70/CNC = MF 70 + steppers) 
excellent result, as far as I could see.
It took me a lot longer with the files for wood.

[DiTBho]

Have you tried a nibbler? Or if you want to be cheap a nibbler attachment to a drill.

not yet, but "I am all ears" 

[Psi]

Water jet would probably work great, but I am not aware of any solution which is even in the ballpark budget-wise.

You can DIY it with a pressure washer and the right crystal/ruby orifices.
but you have to hack the safety valve to increase the pressure.  It does work though, if you wanted to go that route. Search youtube for pressure washer water jet.   Dunno about longevity when running at that pressure, but im sure there are lots of guides online for it.

[Pinkus]

I am using a cheap Chinese CNC for cutting plastic (e.g. cut-outs in housings). Look for CNC1419 or similar.
It is totally fine for this kind of job. Good thing is you can save several often needed jobs on a SD card and then just scroll through the menu and select the one needed now (you need to purchase the option "offline" which just costs $10 extra).
e.g. https://www.aliexpress.com/item/32985583966.html

[tszaboo]

Have you tried a nibbler? Or if you want to be cheap a nibbler attachment to a drill.

not yet, but "I am all ears" 

I have no idea if it would work. But sounds plausible, they are made for metal.
Let us know if you gave it a try.
I also didn't get the joke if there was one.

[PlainName]

(you need to purchase the option "offline" which just costs $10 extra)

The very existence of an offline option (as opposed to an online option) is a red flag to me - shows the manufacturers mindset and direction.