Custom size kossel

Hello everyone,

I already built a Cartesian 3D printer (Tom's Hardware Dolly) and a MPCNC, now I'd wish to build my own delta printer. To be more precise, I'd wish to create a pick-and-place machine using the delta layout, so my specs are a little different.
Using this DeltaBot Calculator I was able to write down some measures:
Radius: 235mm
Height: 600mm
Arm len; 395mm

I think I'll use 2020 aluminium profiles, but my biggest question is about the width frame: how can I calculate the length of connection sections between "pillars"?
Is there any calculator for the whole build?

Thanks in advance!

The length of the horizontals depends on the type of vertices you use. When I switched by Kossel-derived printer from 2020 to 2040 verticals and the corresponding vertices, I had to lengthen the horizontals by 35mm.

Edited 1 time(s). Last edit at 01/27/2019 01:05PM by dc42.

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Large delta printer [miscsolutions.wordpress.com], Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Honestly I'm thinking about using the "official" printing list that you can it here: https://reprap.org/wiki/Kossel
Should I use some basic geometry to infer the actual distance? My hunch is that the "radius" refers to the circle circumscribing the triangle made by the three pillars, am I right?
Looking at the printed pieces, it seems that there's some tolerance to handle shorter frame pieces, is that the case?

Sorry for the silly questions, but I've never built a delta printer before

I was thinking about something like this: [danalspub.com]
Suggestions? Are there any hidden surprises?

Delta printers need to be built accurately so that they can be calibrated to give good prints. My first delta used printed ABS vertices, and one of the problems it had was that the verticals were not quite perpendicular to the horizontals. So I switched to machined aluminium vertices from Robotdigg for my second delta printer to avoid having that problem again. You can find the details of my build at [miscsolutions.wordpress.com].

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Large delta printer [miscsolutions.wordpress.com], Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

I think 2020 extrusions will be a bit skimpy. Have you done any calculations of how rigid the towers need to be? I used 2550 extrusions on my delta with a slightly smaller bed radius (310mm diameter).

Misumi sells machined extrusions.