convert traditional machine or build router?

[JAZZCNC]

The other alternative that I keep returning to is building a cnc router. I'd be going for a welded steel fixed gantry design with an effective work envelope of maybe 50 x 60 x 10cm.

If you have the equipment and knowledge to do this then It's a no brainer to DIY IMO. If you want a very strong machine that doesn't take up much space then have a look at Sean's in link below.
Build this style machine in steel and you wont get cheaper for the same strength (use supported rails thou.!!). It will match any cheap mini mill. Problem with Mini mills and aluminium is the spindle speed.? Far too low to give decent feed rates. Higher spindle speeds are much better in alu and mixed with flood coolant then you can shift some serious material and still have a very nice finish.

http://www.mycncuk.com/forums/router...t-machine.html

[Henrik]

Thanks for all the comments, guys. Exactly the kind of real world experience I couldn't find using google :)

That machine linked to above looks fantastic! I think I'll end up building something of similar size to keep as much rigidity as possible.

[Henrik]

Just to give a little update to this thread, I actually went and bought a very cheap adcock and shipley horizontal milling machine on ebay instead, ahem.

It is a production style machine, so pinion/rack on the x axis, and also not on the z-axis, but the y axis at least has an acme lead screw with 0.001" backlash.

Compared to my old centec, this machine is in way better condition, with no discernible play on the table, but obviously the x and z axis have to be sorted for it to be sensible.

I'm currently in the process of converting the x axis with a m16 threaded rod (i know, i know), as it's what i had lying around. Obviously not ideal, but a huge improvement on 1 turn = 5 inches :)

My plans for the machine is to use the horizontal part as a little lathe (er40 collet to hold a bit of bar), and i'll also make something to hold a small lathe chuck for non circular work pieces.

I'm also going to build/bodge on a vertical head of some sort, with built in travel, as that essentially sorts the z-axis issue (I can move the z-axis, but it requires gorilla strength).

Might keep this machine as a manual one and use it to build the parts required for a CNC machine, as suggested earlier in the thread, as I'm guessing it's not ideal for CNC conversion, given that the table doesn't sit on rails etc.

As for CNC machines, I'm thinking of starting off with a CNC lathe instead of a milling machine, seems more useful for the bits I need doing for my car hobby.