Band Clamp Corner Blocks (Extended)

Update 2020-10-22

Based on an idea in feedback from Avocadosandtomatoes, I've added additional angles to the clamp to support clamping shapes beyond rectangles (and the new AngleBlockClamp.scad file will allow you to create additional ones if desired). I've included STLs for the following:

• Triangle at 60 degrees
• Hexagon at 120 degrees
• Heptagon at 128.571 degrees
• Octagon at 135 degrees

The same pads will fit these clamps.

First Version (90 degree corners for rectangles or squares):

Based on a design by henryarnold, this version:

• Extends the clamp pieces to provide more surface area on the corners (which adjusts the pressure profile, so may or may not be desired - your call) and provides enough space for TPU pads.
• Adds TPU pads to the clamping surface in an effort to reduce the chance of marking to zero - something which matters more with softer or pre-finished woods. Pads are optional
• Gives a deeper offset for the band around the object providing more room to fit some bar clamps in along those linear edges
• Designed for reliable no-support printing

I made this because I was building a big table using one of the softest hardwoods (poplar) as a trim - which isn't generally a good idea, but that's what I had on hand - and COVID remote schooling required me to make another school desk without much notice. Also, I also had some heavy staining going on, so the pieces were finished prior to glue-up (again, not always the best approach, but a 10 year old was doing the artistic design) making the finish more susceptible to clamping damage. I also like TPU for this type of thing.

This design also has a odd curve at the top of the band channel purely to make it printable without supports. It takes 1" band as is, but can be stretched in the slicer to fit whatever dimensions you require. That curve needs to be at the top of the piece when printed, away from the bed.

Clamps themselves were printed in PLA, which in this configuration I feel is perfectly strong enough. Some people think you shouldn't use PLA because they'll explode. If that worry keeps you up at night, use ABS or similar.

Print Settings

Printer Brand:

Prusa

Printer:

i3 MK2.5

Rafts:

Yes

Supports:

No

Resolution:

0.32

Infill:

40%

Filament: Sainsmart & Inland TPU & PLA Red & Orange

Notes:

For the PLA Clamp:

* 8 Perimeters (remember, strength comes from the shell not infill) * 7 Top & Bottom Layers * 40% Infill

For the TPU Pads:

• 7 Perimeters (100% solid, no infill)
• Limit volumetric speed to 1.35mm3/s

Category: Hand Tools