1)Get rid of the locks, legs, and feet then just use a 4″x4″? Hard to level…
Easy and effective solution. The leveling can be done relatively easily using shims or a few layers of paper. The only concern I have would be wood expansion/contraction overtime.
2)Use angled braces? Extra parts…
Better than nothing but it will be weak.
3)Make all 4 corners the z axis? Yikes…lots of hardware and electronics
Too complicated, and it will need 3 more motors. Leveling will be a nightmare and rigididy will vary depending of the height of the machine, so results won’t be constant.
4)Hard mount the corners,make the z axis the bed? harder to make a table, lots of carpentry involved.
In my opinion, the best solution, but it will not be for beginners and it will ruin the whole point of the MPCNC: being an entry level easy machine for people to experiment with.
But it could be another complementary version. Like beginner version, versus experts version.
5)Rework the current parts use two tubes side by side, make the lock and feet fit both? A little extra tubing.
Could be an easy solution and this should work better than the original, if I understand correclty what you are saying (putting two tubes at each corner, oriented at 45 degree, one inside the frame and one outside, right?). I don’t see any downside aside from extended printing time for all these corners and supports. Might do the trick. Could also add more tubes, 3 or even 4.
6)Use the current setup and add allthread from the top through the table and bolt it all together? I see a lot of parts getting crushed this way.
It will improve rigidity, but needs to be crazy tightened, which will be hard on the plastic parts, but they can be made pretty solid. Tightening will have an impact on leveling, so it will make things complicated: people will have in some cases to chose between a leveled machine and a rigid one.
7)New feet, the corners and locks seem solid to me, the feet seem to be the weak link? Easiest.
In my opinion, new feets will greatly solve the issue, but I can’t think of any feet design who can solely solve the problem, unless having massive feets that will take hours to print. Unless, as mentionned above, a feet design using sereval tubes. Could be two or cound even be 4.
#7 plus a place top mount guy wire for the taller builds? Options are cool.
Didn’t understand this point.
In my opinion, if you wish to have maximal rigidity without making too many changes, the solution 5 is the best. It will not solve everything, but it will definitely be better.
An other solution would be to print the feet/tube/bottom corner support as a whole, single part. But it will take a long time to print.
I believe the best way to have something rigid is either the technique I used for my table, which has a lot of other advantages, like versatility but makes things very hard to square the first time, or, as someone else suggested a few days ago, to attach the structure to a wall, which is clearly the best thing to do but might not be practical for everyone.
As for other suggestions I have:
-add parts or spots to fit the endstops, especially on Z axis
-Add some cable management parts,
-consider a more rigid center carriage, maybe using two parralel tubes instead of just one per axis. I think this is not easy to do but it should be feasible.
-Same remark for the Z axis, it may be possible to use 3 or even 4 tubes intead of 2, by mirroring it. This could greatly increase it strenght, which could be useful for tall builds. Not sure this is a priority though.
Hope that helps!