newbie requires help

[John Auty]

hi, i am fairly new to the world of cnc mills, routers and equipment. i have worked with such equipment for the past few months, but the equipment i use is fairly small. i require a large cnc mill that has a table area of 6ft X 6 ft or 4ft X 4 ft and a vertical travel of around the same as the width. i require the machine to cut out slugs for radio controlled boat hulls and to cnc large aluminium and steel parts. could anybody point me in the right direction for plans etc, as i dont want to purchase a complete machine. the pieces of steel i will need to cut / mill will be around 1ft square, so if i could possibly have plans or help for a smaller machine for the heavier metal cutting and plans or help for a larger machine for cutting foam or mdf that would be great,

Cheers

[mxtras]

Get out your checkbook. And your engineering books. And your calculator.

You are out to spend some pretty serious money, so you had better make sure your design is good.

What is your expected budget? Building a 6' wide machine rigid enough to machine steel isn't going to be easy or cheap.

You might want to investigate buying a used mill and save yourself a lot of effort if you plan to machine steel.

Scott

[damae]

I agree with mxtras!

The x and y are within range of many DIY CNC routers. But to do a 4' Z axis is pretty amazing! I suggest you build (or buy) two seperate machines. One for foam (with the HUGE z axis) and a second one for steel. I'm assuming that you want to machine big foam parts and small steel parts, of course.

If you want to machine steel parts 4' high, you should consider buying a used VMC from used equipment dealers. I've seen some large VMC machines on ebay for $35k, although usually not as large as 4' cubed! One catch is that you will need 3 phase power to run such a VMC.

You can save a lot of money and time if you can narrow down what exactly you want the machine to do so that you don't buy/build more machine than you need...

[joecnc2006]

Foam Cutter, to make molds. then cast your parts, or fiberglass them?

[John Auty]

yes, i require it to cut foam, then fibre glass the mold. unfortunatly i do not have near the 30k required, so i think i may have to down size my foam cutting ideas, would jgro's router be able to cut ali plate? as that would do size wise for the metal cutting. some where i have seen plans for a large scale foam milling machine but i cant find it again, big yellow thing running on two huge rails. looks very similar to the one Chip Foose has but alot cheaper

[mxtras]

A big machine for cutting foam is very possible and could be relatively inexpensive. To expect the same machine to be capable of cutting metals is obsurd. The rigidity requirements of a foam cutter aren't all that great.

Put a piece of foam on top of a large carboard box and without supporting the box, cut the foam with, say - a butter knife. Now try that with a similarly sized piece of aluminum.

Scott

[John Auty]

i am not expecting it to cut both, just a single machine like jgro's for cutting ali and brass plate and a bigger machine for cutting foam, so i have two machines, each one with an individual job

[mxtras]

OK - there ya go. That's a better philosophy!

There are plans all over this site as you know. Happy hunting!

Scott

[John Auty]

that is what i had in mind from the begining, i have found that jgro's is the best so i shall use that design fior the smaller machine.