Hi all,
After much research I decided to take the plunge and buy a bunch of stuff to build a CNC machine. My initial design was pretty simple and after a bit of rough scribbling on paper I came up with what I needed. I ended up going with supported rails for all axes, 300mm for z, 600mm for y and 1000mm for x. I also bought two lead screws for the x axis so it's a rail and lead screw per side. The biggest issue I'm having at the moment is the y-axis and making it rigid. I haven't built anything yet but by looking at my design it looks like a massive point of weakness. The rigidity is limited mainly because of the end support for the y-axis lead screw. It consumes a considerable amount of space in an area where there isn't much to play with and most of all it's an awkward shape in an awkward spot. Basically, by putting where I need it to be severely impacts the connection between the x and y axis. The part is a BK12 if anyone is interested. The FK12 looks like it'd work but I'm not 100% sure about using it.
The pictures I've attached will hopefully demonstrate the problem I'm having. At this point in time I'm planning on making it out of MDF, mainly because I've never worked with aluminium before. At this point I'm considering calling on a welder mate to come up with some kind of very simple but effective steel frame that is as light as possible but solves all my y-axis problems. Ideally I want to make everything out of 8020 but I can't seem to find anyone in my area that sells it and I'm hesitant to buy from interstate in case I miss a part and can't just go down to the hardware store to pick it up.
The other thing I wasn't too sure about either was the y-axis rails orientation. I hope I'm clear in this explanation because I've read quite a few threads where it got confusing... my y-axis will *always* be horitzontal... what I want to play with is the orientation of the rails on the y-axis. In my pictures, the base of the rails are both mounted perpendicular to the ground. I was throwing around the idea of mounting both rails parallel to the ground in an upright position, one above each other with the lead screw in the middle. I also toyed with mounting one rail on its side and one rail in the upright positions (I ruled out one in the upright and one upside down). But again, it doesn't matter which way I place the rails, I still need to deal with the end support.
Thanks for reading, looking forward to your responses :)
Cheers
After much research I decided to take the plunge and buy a bunch of stuff to build a CNC machine. My initial design was pretty simple and after a bit of rough scribbling on paper I came up with what I needed. I ended up going with supported rails for all axes, 300mm for z, 600mm for y and 1000mm for x. I also bought two lead screws for the x axis so it's a rail and lead screw per side. The biggest issue I'm having at the moment is the y-axis and making it rigid. I haven't built anything yet but by looking at my design it looks like a massive point of weakness. The rigidity is limited mainly because of the end support for the y-axis lead screw. It consumes a considerable amount of space in an area where there isn't much to play with and most of all it's an awkward shape in an awkward spot. Basically, by putting where I need it to be severely impacts the connection between the x and y axis. The part is a BK12 if anyone is interested. The FK12 looks like it'd work but I'm not 100% sure about using it.
The pictures I've attached will hopefully demonstrate the problem I'm having. At this point in time I'm planning on making it out of MDF, mainly because I've never worked with aluminium before. At this point I'm considering calling on a welder mate to come up with some kind of very simple but effective steel frame that is as light as possible but solves all my y-axis problems. Ideally I want to make everything out of 8020 but I can't seem to find anyone in my area that sells it and I'm hesitant to buy from interstate in case I miss a part and can't just go down to the hardware store to pick it up.
The other thing I wasn't too sure about either was the y-axis rails orientation. I hope I'm clear in this explanation because I've read quite a few threads where it got confusing... my y-axis will *always* be horitzontal... what I want to play with is the orientation of the rails on the y-axis. In my pictures, the base of the rails are both mounted perpendicular to the ground. I was throwing around the idea of mounting both rails parallel to the ground in an upright position, one above each other with the lead screw in the middle. I also toyed with mounting one rail on its side and one rail in the upright positions (I ruled out one in the upright and one upside down). But again, it doesn't matter which way I place the rails, I still need to deal with the end support.
Thanks for reading, looking forward to your responses :)
Cheers