Is there any difference in how deep they can carve, accuracy ect?
Is the longer span on the rails with the 1000 going to be a noticeable issue?
The machine is supposed to be used on small engravings (100x60mm) and 25x10mm cutouts in 2mm aluminium.
The engravings are detailed, and maybe 3d milling in that size on a later time.
I would also like to have the option of making 3d open boxes (110x60x40) from a slab of aluminium.
For more freedom in making stuff i want the biggest machine possibly for other projects in wood.
I know this is a lot to ask for from a cheap machine, but have limited funds.
Either machine will work for aluminium, the only real difference is that the X axis on the 750 will be slightly stiffer than on the 1000. Being stiffer will increase the cutting speed and accuracy at high speeds. Neither machine will be able to compare to the speed that you will get from a commercial machine that weighs hundreds or thousands of pounds though.
If you’re going to do aluminium for hobby purposes and can devote many hours to a single small project, then either size machine will work for you. Aluminium is absolutely within the capabilities of the machine, and small modifications like Y axis braces can help even more. All it requires from you is patience.
To the best of my knowledge and understanding, the accuracy on them both should be close to the same if you brace the Y axes and go slow and shallow.
In your example, there’s no reason you can’t swap out boxes, re-zero, and go. No need to recalibrate anything. You will want to re-zero each time though because the typical cutting depth for aluminum seems to be about .005" or less, so if a box is just .002" higher you may break a bit just from trying to bite off too much.
Sorry, I put that in inches instead of mm. .005" comes out to .127mm. That would come out to about 16 passes to carve down 2mm.
If you search the forums for aluminum, you will be able to find some good threads showing the various feeds/speeds and projects that have been done. @CharleyThomas makes some great touch plates out of aluminum, he would be a good person to get in touch with about aluminum speeds and finish quality and such.
One other consideration is that the longer span will allow for a third again greater belt stretch.
I also suspect that there’s some underlying engineering calculation which made the 750mm width appear at the same time as the new Wide MakerSlide.
No one has yet complained of a CNC machine being too rigid — if your work will fit in the 750mm size, get that — worst case is you can occasionally index parts and cut in sections, or expand along the Y-axis w/ side supports.