Wife wants a SPACE10 GrowRoom, an open source Ikea inspired urban garden.. It needs a CNC and cuts pieces forms from 4x8 ft. sheets, some of the larger parts are ~1700mm long. so here my chance for a new toy . Can you butt splice VSlot extrusions and still use it as the rail/guide. Woud there be any issues with wheels rolling over the joint?
Interesting design concept. Looks like a fun project and likely within reach of an OpenBuilds system. A couple things to consider though. The larger issue here is the width not the length. Flex in the gantry beam can be an issue but this is something that is easily resolved by reinforcing or doubling the gantry beam. That then leaves the issue of length. With enough wheels and careful alignment you should get reasonably smooth continuity across a joint. The problem though is an 8' usable bed length pretty much requires a belted system and belts can stretch resulting in inaccuracy of the cuts. This can be minimized with double belting but in reality there is a much more workable solution. With "tiling" (i.e. pin registration) all that is really important is the width of the machine, being wide enough to fit the 4' wide sheets. Length can be anything you want as you simply cut a section and then slide the sheet forward to cut the next section. The pin registration sets it exactly where it needs to be to continue the cut. So if you build 4'x4' you can still get the same results without the problems that come from building for an 8' length.
I think I understand. Is the "pin registration" handled in software or do I need to split my ACad dwg into two halves?
It also works well if you want to do two-sided milling. Skip to about 4:35 to see the reference pin placement.
What is the difference between a Lead 40x40" and a WorkBee 40x40"? At a glance they appear the same, both are lead screw drive. What would be the max depth of cut for say a 1/4" end mill in birch/maple plywood and pine plywood?
One design is older than the other, power or strength wise there is no significant difference. The Workbee has a slightly greater usable width. The Lead system is more easily upgraded.