CREAT3D Creative Hub: The Hand Clamp Screw
Friday, 18 August 2017 | Sachin Patel
CREAT3D’s Creative Hub Project Number 1: Hand Clamp Screw
The hand clamp screw is a design taken from Thingiverse, Thing 2403756, by jakejake, published 25th June 2017.
Knob & Thread on the Markforged
Printing in Onyx (Nylon with micro carbon-fibres) gave a really good finish, with strength and rigidity to the prints, necessary for the specific Knob and Thread elements of the printed parts.
Tip: Don’t forget the set up for using multiple parts on a single bed in Eiger, the slicing engine for Markforged. Once you have processed your file and ‘Add Part’ to your build plate, you’ll need to ensure that each part is the same resolution, otherwise the software will warn you that the build can’t be exported.
Pads on the Form 2
We used the Formlabs Form 2 SLA technology for the “Pads”, in the Formlabs Flexible Resin, so as to provide some extra grip to the clamp, and protection to the item being clamped.
The Form 2 creates an excellent surface finish and good accuracy. However, the surface quality of the finished printed part was slightly affected when the support material was removed. Due to the nature of printing with Flexible Resin, the support columns have a wider diameter. Cutting the support away isn’t difficult, but where the support structures in contact with the print surface were removed, some scarring was left behind.
This is where orientation is key. It is often best to avoid placing flat faces directly onto the plate of the Form 2 SLA Printer, as this can lead to peeling and a poor initial surface for your print. However, in the case of this specific part, it may have been worth trying to print on the flat face, or adjusting the design to add a couple of additional base layers.
Aside from a small visual imperfection, the print quality was fantastic, and using the flexible material provided additional benefit to the clamp.
Remaining parts in PLA and ABS
We split the remaining parts across the UP Box Plus and Ultimaker 2 Extended+, 3D printing in ABS and PLA respectively. The Threads, Pins and Hinges were printed in ABS, due to the material’s qualities, providing good part definition and stiffness. These parts were also required to fit into the other parts to build the finished clamp, so it was important to get good dimensional accuracy.
The finished clamp
Once all the parts were printed, there was very little post-processing needed. The parts fitted really well and easily together, even though they were printed on different machines, the common tolerances work together to ensure a good fit to the overall finished printed part.
The design of the clamp is also well thought out in terms of its assembly and use. The two main screws (even with their 3D printed threads!) are smooth and control the bite of the clamp so it’s pretty versatile.
You can check out the print settings and material used in the table below, along with the approximate cost and time taken.
CREAT3D’s Creative Hub, Project Number 1: Hand Clamp Screw. Which is now proudly clamping on our workbench.