Replacement Shop Vac Latch

Shop Vac Latching Clip

A secure latch for Craftsman Clean 'n Carry 4Gal. 5 HP shop vac. To remove the broken latch, loosen a few screws, pry up the top section, and replace.

Quick start. The included .3mf file contains the most common slicer settings. Merely change filament and printer type, reconfigure (or remove) the variable layer height settings in Plater, and re-slice.

Slicing Strategy

This will be a functional print, not something to sit on a shelf and look pretty. It should withstand slamming into things, pulling and yanking. Fused deposition modeling (FDM) 3D prints are weakest perpendicular to the direction of the layer lines. So that is the direction we chose for our layer lines to run.

But to get these layer lines lined-up the way we want, we have to slice the part balanced along one edge, which will easily break loose from the print bed during printing. Thus, we will have to plan for extra layer adhesion during slicing. This includes

• using automatic supports,
• priming the nozzle to ensure a consistent first layer,
• printing a skirt line to ensure flow has started,
• adding a brim to increase surface area adhesion,
• and slowing down the print to minimize shear forces.

Material Selection

PETG. This filament type resists breakage about as well as the original tool plastic (probably PET). And it works relatively well on cheap, consumer-grade 3D printers. PLA is even easier to print. But it is often too brittle and doesn't stand up to heat well. Do not use it if this project will sit in a hot storage shed or van on a sunny day.

Printing PETG

Moisture in the filament made this test print difficult. It had been raining all week. The next print looked perfect after drying.

Adhesion issues. PETG may resist adhering to the print bed. It curls up and sticks to the nozzle, where it forms a blob, and plugs the nozzle. And, when it does finally adhere, it forms a permanent bond, making it difficult or impossible to remove without damaging the build surface. A temporary surface coating, such as glue stick or hair spray, helps solve both issues. PETG absorbs moisture, so it must be dried. Even new filament sometimes needs drying before printing.

Wet filament. Even with all these precautions, the first test print started off not adhering to the bed. The new filament roll acted like nylon. Very tough and stringy. Was it mislabeled at the factory? After cranking the temperature to 245, it finally stuck. The surface was rough though. That was moisture. Reducing temperature to 235 and increasing flow to normal salvaged enough of the remaining layers that it was possible to use it for trial fitting. The dimensions were slightly-off anyway. After drying in an oven for 4 hours, at about the temperature of a hot day, it printed fine.

Success! A successful print is just the beginning. Now the real work begins. Removing PETG from the print bed can be an ordeal. Try letting the print bed cool. And if that doesn't work warm it up again. It helps to have a scraper with a razor blade attachment to get under and around the object.

Finish and prep work. Painting, sanding, and coloring are optional. This part should be fully functional and ready to use, after removing the supports.

Support removal. With the aforementioned razor knife, carefully weaken or cut away between the supports and the print, wherever it is convenient to reach. Removing supports is now much easier. A small needle-nose pliers helps to pry and pull away the remaining supports.

Installation.  To remove the broken latch, loosen a few screws, pry up the top section, and replace.