Quote Originally Posted by PilotTom View Post
Thanks for the advice Martin and Ross.

I have made a start on some designs after reading through a heap of build logs. Seems that for my size of machine I would be pushing the budget too far to get HIWIN 15mm rails on all the axis. Perhaps I will have to have HIWIN on the Z and build in some upgrade paths for HIWIN on X and Y in the future if I find the machine needs it.

Also thanks for the info on welding problems in regards of accuracy. I think I should be aiming for something similar to this one, in particular JAZZCNC's machines in the second post of this thread http://www.mycncuk.com/forums/diy-cn...ign-build.html

The info on the screws is useful too. I hadn't anticipated the torque required for aluminium, I was worried about whipping. Speed is of secondary concern after the accuracy. I would rather run for 10hrs and be accurate than 5hrs and be sloppy. I will design with pulleys so I can have a bit of choice over it.

I am having trouble finding Aluminium profile with prices listed to get a feel for what is affordable. Are there any preferred suppliers? I need to get a feel for how much I can expect to spend to help with design choices.

Thanks.
Tom.
Hi Pilot Tom
Hope you are getting on well with your design. I have worked up the final drawings and going with Jazz's approach on the use of 80x40 heavy extrusions arranged in an L pattern, with 20mm toolpate for the Z axis and 20mm plate for the gantry sides. After just purchasing a VFD and 2.2kw spindle, it sure is heavy! so stiffness of the gantry is important.

The guys on this forum give honest critical advice which has made the difference in my design and will ultimately save time and money. My buiild will start in a couple of months so watch the build log.

Kind Regards
Mike