Drywall Repair Fixture

This is a fixture that provides a back-up structure for repair of through-damaged drywall.

Yes, there are other simpler easier ways to do this, but when you are holding a hammer, pretty soon everything looks like a nail. I have a 3D printer so...

This model is for about a 2-1/2" X 4" hole but can be scaled up as needed. It consists of four 3D printed pieces that, when installed, bridge the gap between the wall studs, fills most of the hole to be patched and leaves only about 1/8" for final repair with spackle or drywall mud.

The middle plate can be scaled up in X and Y at print time to accomodate larger repairs, but the jackscrew must be scaled up by the same amount so the thread diameters remain consistent with one another. The middle plate long axis should be sized to bridge the short axis of the rectangular cut-out.

The Z axis should only be scaled if the void in the wall is significantly different than the standard 3-1/2" stud width. When installed, the outer end of the jackscrew should be approximately flush with the outer face of the middle plate.

The middle plate should be sized so that it can be slipped into the rectangular hole at an angle and then turned so it will bridge the hole and be held against the inner surface of the broken drywall by the jackscrew. One side of the middle plate is heavily radiused to help facilitate getting it through the rectangular cut-out. The un-radiused side should go toward the inner surface of the outer drywall.

The outer plate can be scaled as needed to fit the rectangular cutout with about 3/16" clearance all around.

The system works by jacking the middle plate against the inner surface of the damaged drywall, providing a solid base for gluing the outer plate. The outer plate fills most of the patch area and leaves only a small volume to be filled with the drywall patch material.

The inner (round) plate should not need to be scaled. It should work regardless of the size of the repair.

Installation:

Saw out the damaged drywall to a rectangular shape.

Apply a little soft putty to the ball interface between the inner plate and the jackscrew and press them together. This is temporary. The jackscrew will be used to place the inner plate, then pulled off.

Apply cyanoacrylate gel to the back side of the inner plate and using the jackscrew as a handle, press it to the back of the void, approximately centered under the rectangular hole.

When the cyanoacrylate has adhered to the inner wall pull the jackscrew out and remove the putty.

Insert the middle plate, with the jackscrew screwed into it, into the rectangular hole and turn it so that it bridges the rectangular hole and bears against the inside of the drywall.

Carefully turn the jackscrew in while holding it outward until the end of the jackscrew engages the socket in the inner plate. Tighten the jackscrew until it's snug. Only use enough pressure to keep the middle plate in place.

Glue the outer plate to the middle plate with cyanoacrylate gel, leaving a relatively even gap all around.

When the CA gel is dry, the spackling process can begin. The round holes in the face of the outer plate are dovetailed on one edge and the outer edges of the plate are beveled inward. These features are intended to provide a mechanical grip between the spackle and the outer plate.

Printing Notes:

PLA

0.8 shells

12% infill