I'm starting a project to get a CNC mill /router at the London Hackspace (a UK maker community). I was hoping that you guys here could give me some advice about what directions we should be looking in.
I've surveyed members about what they want and how much they're willing to donate towards getting such a machine. The results were:
- the biggest group of people - $2500 budget - would be happy with a 12" x 12" that could do PCBs, wood, plastic and softer metals such as aluminum;
- a further smaller group - taking the budget up to $3000 - wanted the machine to be able to do up to 20"x20" or 24"x24", cutting the same materials
- another small group - taking the budget up to $4000 - wanted a 4'x8' wood router.
All of these people want to be able to carve complex shapes, but there was little appetite for undercuts, so we're talking 2.5d.
I should clarify that when we're talking about cutting softer metals, it's not simply a matter of cutting out shapes in 1/8" sheets -they want to sculpt complex shapes with maybe 3" of z travel.
Robustness is a priority as it will be used by people like me with little training who won't know how to mother it and will damage it often if there's a way we can. Speed is not important as this is a hobby environment not a production one. Machine will probably be running about 1-2 hours per day.
This budget needs to cover absolutely everything - spindle, software, dust extraction, cutting bed, etc.
Building from scratch or upgrading/converting is realistic option for us. We have in our hackspace metal working tools (mills, lathes, but not CNC) and a laser cutter (wood not metal). We can definitely get plastic parts 3d printed by members who have 3d printers, and may be able to get metal/wood parts CNC machined by members who have a CNC at home.
The way I see it, we have three choices:
1) abandon the people who want 4'x8' and their money, and spend $3000 on 1 good machine 20"x20"
2) get 2 machines for $2000 each: one 12" x 12" for precise work like PCBs that can also cut metals OK, and one 4' x 8' primarily for wood that has less precision/accuracy and can do metals only very slowly.
3) get 1 machine for $4000 that can do 4'x8' with enough rigidity to do metals but good enough on detail to do PCBs.
Which is the right strategy to pursue? Particularly given that we need a machine that is as user-proof as possible.
Once point to reiterate: it's fine if metal cutting is very slow. Speed is not an issue.
Any advice much appreciated.