Hi All, I am a newbie when it comes to the CNC milling but have been keen to give it a go for a while but needed worth while project to do, so now that I have found a project (wife has approved), I am now ready to go shopping but not 100% sure on what parts to buy for the work load. The best way for me to describe the project is that I have large blocks of clay that I need to mill but I can not drill top down like a normal cnc machine - need to go side on. Attached are a few images of my mock up machine. Requirements to mill: 900wide ( left - right - shown as green ) 500hight ( up - down - shown as blue ) 900depth (forward back- shown as red) The grey is the floor supports things that concern me: 1) Is this the best way to do something like this? 2) I should have read <insert here> first? 3) weight of the drill (3kg) on blue ( and what size motor is required) 4) on the blue do dual stepper motors (1 each side) work well or do they run into issues? 5) There is a hole that would be milled all that way though but it gets small every 250mm (like a step down circle) which the drill head will fit inside 6) can I do it for my budget of $1500USD 7) If I also wanted an extra axis to between red and green to go 45deg each way from center. While a parts list would be great - I am more after the you should do/use A part because of B as I want to learn Thanks in advance.
The only major issue I see comes from the 900mm depth requirement. To stick that far out with a 3kg spindle on the end will require a back span for the axis beam and another framework for support. This totally blows your $1500 allowance. With proper belting you can keep the 4 towers to 2 motors which is workable but all the required beams, plates, wheels, and lifting screws are pushing into the $2000(US) range. The 45° angular requirement adds a whole 'nother level of complexity to the project and easily another $500 to $1000. While the mechanics are fairly simple, the additional axis turns the system into a 4-axis machine which pushes you beyond the realm of cheap boards and free software and that gets expensive real quick. (And I really can't offer much help in this area as in the three years I've been watching the forum, I don't recall anyone ever completing a 4-axis machine.)
I think this is a 3 axis tipped up on its side. Maybe tip an OX up and throw in some structural webs on the backside?
