Stackable Horizontal 50ml Tube Clamp for Shakers

A clamp to mount 50 mL tubes to an orbital shaker. The tube fits snugly in the bottom clamp, the cap sinks into a divot so the rim is prevented from moving while the shaker is in motion. The bottom clamp screws into the shaker platform with a #10-24 screw. This clamp was designed for a MaxQ 2000 orbital shaker so the screw holes are spaced for it, 54 mm apart.   

There are spots to glue in magnets so that they close securely. A second bottom rack can be screwed into the top of the first rack, using the same screws for mounting to the shaker, making them stackable.

Printing Directions

Printed in PETG, which is resistant to a lot of chemicals. Print the bottom support flat on its bottom side. Print the top upside down. No supports are needed. 

I have a Prusa XL and the 8x tube holder will likely only fit on that printer (at 337mm long). I modified, added additional screw holes for greater flexibility, and made the 6x tube holder which is 244 mm long. I've uploaded both here.  

Assembly

The model uses 8 1/4" cube magnets glued into the corners so that the top will snap securely onto the bottom. I glued them in with super glue (gloves are helpful to wear so you don't worry about gluing your fingers together). It's important to glue them in the correct direction so that they don't repel each other. 

For Use

Screw bottom clamp into the orbital shaker, then slot in the 50mL tubes. Snap the top clamp on. You can then screw a bottom clamp into the top clamp and stack the clamps to shake large amounts of 50 mL tubes at once. 

It is not necessary to use all the screw holes, I included all of them so that there was flexibility when attaching it. Use as many as needed that the clamp is held firmly to either the shaker platform or the other racks. Use caution when stacking the clamps, I have not tried it any higher than 3 high at 200 rpm and cannot promise things won't break on your setup.