800x600 steel router build/design

[Semlloh]

Hi All,

This is the start of what I hope to be a pretty good first CNC router. My aim is to build a router that will mostly to 2D work with material priority to aluminium,1.6-3mm steel and wood in that order. I'v done a bit of reading around here and a few other places so hopefully I'm on the right track. It is smaller than I would like but I cant quite justify the outlay without a bit of proof of concept.

The design is largely based around materials I have on hand, However I'm happy to be guided to another direction if I'm way off.

Drawings are very preliminary as are my fusion skills. That said there are a lot of detail not in the models I didn't want to get to far into it without some idea I'm not way off the mark. I haven't even started on Z axis yet. I plan to use the epoxy trick to get some good flatness.

Here we go, The Details.

Cutting area- X 600 Y 800 Z 150
All linear rails 25mm
Ball screws 2510
spindle 2-3Kw


Gantry 150x50x3mm RHS with 12mm plate welded
Frame 89x3mm SHS

Electronics, Here is where I get lost

I'm leaning towards the AXBB-E breakout board.
Steppers and drivers I am inclined to look for something cheap at this stage with the thought to upgrade later. NEMA 23 4Nm

That's about as far as I've gotten so far. CAD screenshots below, if something looks wrong or doesn't make sense please let me know. My main question Is Does the basic structure look sound enough to progress with the design. What am I missing?

Thanks for stopping by.
Tim

[oliverkell]

For that kind of machine, rigidity is key, and mild steel will do better than aluminum in this case. Filling sections with epoxy granite could help, but going with thicker steel in critical areas might be a simpler solution. If cost is an issue, you could look into heavy melting scrap to source material for a lower price and machine it to spec instead of buying everything new.

[m.marino]

Some items to remember in the design phase:

Account for the width of your Z module on the gantry and also the type and position of your end stops. On some sketching or on the actual CAD drawing rough in basic wiring pathways and?or cooling as it will bite you in the backside later for not doing it.

What thickness and type of material are you planning on using? What form of bonding are you going to use between elements and materials (welding, bolting, high tensiles epoxies)?

Remember to account for tool length of the longest tool you plan on using and include that into your Z module length. Also make sure that your Z module is wide enough to aid in the reduction of the cutting forces that will be feeding back up from the tool head.

A lot of this is simple but often over looked. I learned many of these lessons on this very sight when working on the design and functionality of my rebuild that changed into a complete design and build. Still can't thank JazzCNC enough for the knowledge and help he gave when i was starting up. Now that machine is enroute to the US and will be getting some upgrades and put right back to work.

Biggest suggestion is follow the KISS principle. As that will keep you from going down a rabbit hole that WILL give you grief in the build and in the ability to use the tool once built.