homemade cnc mill in mind project

[ataxy]

Hi there people i have a few question that i did do a fast search in the forum but did not find what i am looking for so ill go one by one as my cnc mill project go and will update my first post with the answer i found to each question i have

Ok so here whe go, i decided i would take the longer and i guess what will be a more expensive machine at the end way of doing thing by making my own cnc but i came to conclusion that i will learn more this way and i will be able to decide more what my machine will be.
so here is my basic idea:
I all ready have a drillpress (dont worry i dont plan on making a mill out of it did it with another and it works allright to do butcher job as the best i got from that was +/- 0.015 ,on aluminium or brass but dont even think of steel, with lots of thightning and mod) that ill use for the simple hole drilling that do not need precision

As for the first milling job i have to do to get the project started i might have access to a knee mill (but thats not certain) else ill try to save my money and go for an x2 from Princess Auto as anyway the actual head i intend on using at the end is a beefed up x2 head

Ok now motor for my project, i plan on using a treadmill motor, like those 2.5hp 130vdc one.

As for axis motor i was thinking of something along nema34 +/-500oz motor, i know lots of people would recommend servo but ill lay the same argument as other there to expensive.
For the axis id like to get something around 10 tpi ballscrew dont think if ill go for grounded ballscrew i will probably go for rolled one.
also i was wondering what should i look for as far as linear way should i go round slide, rectangular slide, or stay with a dove tail slide.
i have a bit of a questionning, are stepper driver and controller the same or do you need both?

also i was thinking of doing something similar to the cncbridge.com table out of polymer concrete since i want a travel of around 20x15 for a table that is about 24x20

i will probably have more question as it goes but for now thats about it, now this is a first idea of what i want to do it may change in the long run but for now thats it

[ataxy]

ok i was wondering if this would be a good idea but i would also add a sort of concrete/polymer mix to the column assembly
this is a rapid sketch from the top of the head/collumn, i would add linear slide to each side of the collumn and would join the head to those pillow by plate on each side of it, the linear slide would be attached by the same screw that would go true the collumn

[ataxy]

ok i would need some info does anybody know where i can get the measurment for the dovetail on this part of the x2 mill/drill

[ataxy]

ok i decided to take a slightly different route to make my first mill i saw a enco type cross slide table and tought that aside from the cheap screw it use for its movement its construction is pretty rugged so what i plan to do is actualy use two table to make the machine one for the x.y movement giving me around 11x7 and another to make the z axis so 11 so my idea would be to attache the table part of the y axis of the second table to a steel box section 6x3x20 to make the column the box section could then be filled with some sort of polymer concrete to reduce vibation and lock in place the bolt that would hold the table in place the face on wich the table would be attached would be previously milled flat to get the best matting surface as possible the column would be welded to a steel plate around 10x20x1/2 make the base where the second table would be fixed to make the x and y axis, i might also use the left over base of the table i used to make the z axis to help the y axis as i heard that the enco type table are only half way on the dove tail when they reach the end of there travel
as for the head i plan on making a head out of a R8 spindle for the x2 that they sell at littlemachineshop.com for bearing i will use two double row radial ball bearing i found at a flea market marked fafnir 5207w c1 each are 1.06x2.834o.d.x1.377i.d. each have two row of 9 .375 bearings that would be for the 35mm section of the spindle and one barden 208h thrust wich is .710x3.150o.d.x1.574i.d. i unfortunatly havent found any 30mm i.d. bearing that i could fit on the top part of the spindle but i guess since i would have 72mmof bearing support on the lower 109mm part of the spindle i should not get that much deflection out of the spindle itself as the 80mm left would be mostly belt pully and thightning nut and a spacer anyway let me know how it sounds