Parametric tube stand, designed in OpenSCAD

Ever had to work with quite a few NMR tubes using eppendorf/falcom stands or pipette tips racks? Tubes won't stay in place, use too much bench space, mix.

So I decided to design a tube stand. And I made it parametric, so it can be used to generate arbitrary stands for different kind of tubes and sizes as desired. I posted a picture of a "working" model with holes separated by 15 mm and of a "storage" model (more compact but more difficult to manipulate) with holes separated 10 mm.

You can preview the assembled tube stand by uncommenting the final lines, and then render each part separately as STL to print

Parameters

`holeDiam=5 ; //diameter of holes: 6.5mm for NMR tubes; 12mm for eppendorf tubes; 18mm for 15ml Falcom tubes; 30mm for 50 ml Falcom tubes; 14 mm for cuvettes;`

squareHoles=false; // square holes for cuvettes
w_distance=15 ; //distance between the center of the holes in the width direction. Has to be larger than hole radius
d_distance=15 ; //distance between the center of the holes in the depth direction. Has to be larger than hole radius
w_num=5 ; //number of holes in the width direction
d_num=3 ; //number of holes in the depth direction
margin=8 ; //margin between the border of the holes and the sides of the rack

`central_plate=true; //whether to include a central plate``base=10 ; //height of the base plate`

first=30 ; //height of the central plate
second=100 ; //height of the second plate 30 mm for eppetndorf tubes, >50 mm for Falcom tubes
top_margin=10 ; // margin between the top plate and the end of the side plate

//size of the number labels. Use at least 3 for clear printing
numberSize=3;

`//plates thickness, recommended 3> 2mm to get reasonable strength``thick=2;``//plates supports. May be necessary for thin walls and/or larger racks``add_plate_support=true;``//Side plate engraving. Set true to add svg file with text or logo``engraving=true;`

`engravingFile="Lab5rr.svg";``