I'm working on a complete bathroom renovation, and having never done this scale of project before I've had to come up with a few tools (SharkBite Extractor), tips, and hacks to make it easier for someone without the skill and experience of a trained tradesman or craftsman.

This tool is designed to locate the hole for each shower fixture on large format tile so the hole can be cut prior to setting that individual tile. In most cases only one or possibly two holes might be needed - the shower head and/or tub spout. In my case for this remodel, I have 7 locations that required holes to be drilled into the tiles. 4 body sprays, shower head, a handheld sprayer, and the hole for the shower controller.

(I designed this tool prior to us choosing the tile, and would have used it had my wife picked a flat tile. Turns out, I wasn't even able to use it at all, though it works great as I tried it on some of the sample tiles we had purchased. However, the 3D tile we chose made it rather cumbersome to get an accurate reading, so I used the traditional method of marking the wall and transferring the marks to the tile using a level. For large format FLAT tile of any material, this tool will greatly speed up the hole cutting process and give you very accurate results.)

Supplies

Magnet ($21)
10mm Ball Bearings ($6.50)
10mm Deep Well Socket (or any size with approximately 10.8mm diameter)
Generic PLA Filament
Gorilla Duct Tape (Optional)

TOOLS:

3D Printer

Step 1: Design & 3D Printing

DESIGN:

Designed in Autodesk's Fusion 360 Software
Magnet is designed to be a slip fit into the roller (3D printed part on the left)
10mm ball bearings snap into place in the roller and can not be removed once inserted
The thread on the adapter (3D printed part on the right) is a custom sized thread to properly mate to a 1/2" NPT thread without binding up. It threads in and out easily by hand and has knurled edges for good grip.
The deepwell socket slides freely in/out of the adapter to adjust for distance between the backside of the tile and the depth of the plumbing fitting inside the wall.

PRINTING:

100% Infill
Any filament material (I used PLA Pro)
Print both in orientation shown in images above
No supports are needed

Step 2: Use

Thread in the adapter to the plumbing fitting inside the wall
Insert the socket and push fully until it bottoms out in the plumbing fitting (later the magnet will pull it out)
Add a piece of masking tape to the surface of the tile in the approximate location where the hole will be cut
Dry fit the tile onto the wall (don't forget to use your selected tile spacers)
Hold tile in place or temporarily secure with heavy duty tape like Gorilla Duct Tape
Place the magnet roller on the face of the tile with the ball bearings touching the tile
Move the magnet roller around until it "finds" the socket (you'll hear it snap against the back of the tile)
Trace onto the masking tape the outer diameter of the magnet roller
Remove magnet roller and the tile from the wall
Take the magnet roller and remove the magnet
Using the magnet roller part (with magnet removed) align it with the mark made earlier on the tile and then use the center hole to mark the exact center of the hole on the masking tape
Cut hole in tile and dry set again to make sure the hole is properly located before setting the tile with thinset

Step 3: FINISHED

All done! Thanks for taking the time to read through my Instructable. Please send me any questions or comments you might have. I try to answer them all. Stay safe and healthy! Happy 3D Printing and Tool Making!

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