Parametric Chuck Jaws

Power tools can be very dangerous, and lathes in-particular are likely to be the most dangerous object in your shop, other than you. Whatever you do with this model, and the resulting parts, is your own responsibility, and downloading any of these files constitutes full acceptance of this responsibility. Let's be careful out there.

This model is actually two things:

- a fully-parameterized OpenSCAD package for modeling chuck jaws -- by default, jaws that are compatible with Teknatool's Nova line of chucks.

- STL object files that will work for many situations, for users who would rather not customize and model their own in OpenSCAD. These can be downloaded and printed as one would with any model.

Available Customizations:

- Jaw diameter

- Attachment fasteners

- Jaw height

- Jaw thickness

- "base" thickness

- Style of protrusions to increase grip

Usage Instructions for OpenSCAD package: Requirements:

OpenSCAD version 2021.01 or later (might work on earlier versions, but untested)

Customization Procedure:

Ensure that you have downloaded parametric-jaws.scad.

Open that file in OpenSCAD, and edit the configuration section at the top to your taste. Once satisfied with your configuration, preview in OpenSCAD, and ensure that your customized unit meets your requirements -- i.e. that it will fit on your printer, and has sufficient capacity, etcetera. Render the object, export to STL, and print as normal.

Customization Instructions:

There are three configuration sections in parametric-jaws.scad.

"Jaw configuration"

This section provides settings to control the dimensions of the jaws themselves, such as the height of the jaws, and the size of material which they can hold. Explanatory comments are provided for each variable.

"Mounting bolts"

This section provides settings to specify the bolts which will be used to attach the jaws to the chuck. M6 bolts with 12mm diameter countersink heads are the default. Clearance should be added to bolt measurements, if changes are made here. Bolt length is a configurable value that controls the depth to which the countersink is cut into the jaw.

"Nova chuck specific"

This section contains values that describe the necessary position of the mounting holes and alignment features for compatibility with Nova chucks. Unless the user is attempting to create jaws for other chucks, this section does not require attention. Nova chucks feature two mounting hole locations, one 14mm from the center of the chuck, and one 32mm out. Depending on the values set in the "Jaw configuration" section above, either, or both, of these locations will be utilized.

Usage is a simple matter of editing the first two sections, and optionally the third, to taste. Then previewing the resulting part, confirming that the configuration meets with your requirements, rendering it, and exporting it to STL -- and then printing as one would with any STL.

As a bonus, there is also jaw-holder.scad which one can use to configure a simple holder for each jawset, and an associated STL which will work if you are using M6x1 fasteners.

Printing Instructions:

NB: This model is only one quadrant, and therefore must be printed in sets of four, to be useful.

Orientation: Best printed in the modeled orientation. The alignment ridge is inconvenient, and results in the best orientation being opposite of what might be otherwise expected. Printing in the modeled orientation, with the "jaw" pointing down allows the maximum precision of the alignment face, and optimal mounting holes, and puts the support interface on the least-critical surface. Filament: Any rigid filament will work, even PETG, with the default settings. If you are using a stiffer material, you can likely reduce the minimum_base and mininum_thickness values, but each part is only a few dozen grams, so there's little point in doing so. Infill: Due to the model's generous default dimensions -- necessitated by the requirements of orientation -- infill is not critical. 20% gyroid is sufficiently stiff, even with PETG. Walls: As with the above. Users may add additional perimeter layers but such is unnecessary, unless you are reducing some or all of the model's parameters.

Support:

No supports are necessary __for jaws with a "jaw_id" of 41mm or less__ ( for Nova-compatible chucks ).

Supports are necessary for jaws with a "jaw_id" greater than 41mm. See above for comments on optimal print orientation.

This unfortunate situation is due to the model's necessary interaction with the alignment groove in the Nova chuck. If you adapt this model for compatibility with other chuck designs, you will be responsible for determining optimal orientation and support settings.

Brim: Unlikely to be required, unless your machine's surface adhesion is poor

Additional material required: (4 or 8) mounting bolts of the specified construction (default M6). You can potentially re-use your chuck's existing hardware.