Questions on delta geometry and adapting linear rails for 4080 V-slots

  • Been trying to think this through and thought I'd check here before pulling the plug.

    I just put in an order for the Delta Smart Effector with all the goodies, including the rods. However I'm not certain the rods are long enough for my machine, specs of which are:

    Height: 1000mm
    Diagonal rod length: 397mm
    Printable area: D 340mm
    Delta radius initially set to, and converged by Delta Auto Calibration close to: 157mm

    Tower-to-tower distance (between centers) is 400mm.

    Additionally, I'm currently using wheeled carriages which I intend to replace with linear rails at some point. The thing is, the carriages' rod connection points extend away from, and thus the rod ends are a some 20-30mm (IIRC) distance from the exterior of the towers, which are slotted for the wheel carriages. So if I'm somehow going to install linear rails on these towers, the delta radius is likely to change on top of the rod length. So my first question is; Anyone know if there exist some kind of jigs for installing the rails on the extrusions?

    (All dimensions are approximate.)

    I've read about the "80% rule" (diagonal length from tower-to-tower distance) but I doubt it's of any value. I've also read the recommended minimum angle between the rods and bed should be about 20° at any given position, but I'm having difficulty approximating the delta radius before knowing the specific dimensional changes introduced by the new carriages (I don't currently see how I could mount the magnetic rods' carriage adapters on my current carriages). My second question is; Taking all this into consideration, is 360mm rod length likely enough or should I go to Haydn for some custom length?

    My order is currently on halt until I can at least make an informed decision on whether to include the rods or not. I don't really want to lose too much printable area.

    Any insights greatly appreciated…

  • administrators

    As you are already using 397mm rods, and even longer ones might be better when you change to linear rails and move the attachment points closer to the towers, it's probably best to go to Haydn for custom length rods.


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