3D printable replacement parts for a reverse bale zipper. The slider can be attached to a zipper without unsewn ends. Reverse bale zippers are usually used for water resistant zippers. If you need a standard bale zipper (with the u-shape on top), see my other design.

This is version 2 of the zipper with multiple improvements over the first release:

• increased thickness of top and bottom part for increased strength and rigidity
• increased thickness of the edges with 1 extra wall for increased strength and rigidity
• increased thickness of the connector between top and bottom part with 1 extra wall for increased strength
• some various size and clearance adjustments
• added multiple zipper dimensions after a lot of test fittings
• added a puller with a rounded hole, so it can move more freely

Dimensions
The replacement slider is available in different dimensions.

I have found these sizes to be a good fit for the zippers I have. If they do not fit perfectly on your zipper you can try scaling the closest fit slightly in the X direction. A difference of 0.2mm can have a great effect.

• 4.60 mm width, 2.20 mm height
• 5.20 mm width, 2.20 mm height
• 6.50 mm width, 2.40 mm height
• 7.00 mm width, 2.80 mm height

Print instruction
These are very tiny parts with a tight fit. You need a well tuned printer for this.

• Can be printed with a standard 0.4 mm nozzle
• Print at 0.2 mm layer height (model is designed in multiples of 0.2mm)
• Use Arachne wall generator
• Use 5 top and 5 bottom layers (so that it is completely solid)
• Print slow enough for good layer adhesion. These are small parts resulting in short layer times, especially for the tallest part which are the connectors of the top and bottom parts. Printing multiples at once may help. Try to print as slow as possible, I suggest < 30mm/s. The minimum layer time for cooling of your filament setting probably results in a speed of 10mm/s. Make sure you slow down outer walls as well.
• Using "Small area flow compensation" or reducing your flowrate may help to get better results if you can not get the parts together

Assembly
Place the bottom part below the zipper and slide the top part on the bottom part on top of the zipper and while holding them together try closing the zipper. Having a part of the zipper closed makes it easier for final assembly with glue.

If the test fit worked good, add some glue to the connecting parts of the bottom and top parts of the slider and also the handle. Watch out that you do not get any glue on the zipper itself. Place top and bottom parts again around the zipper and hold them in place. Place the zipper handle on top, but don't forget to insert the puller first. Hold everything firmly together and let the glue dry.

Depending on your printer the top and bottom part may already fit tightly enough so that you do not require glue. I do recommend always gluing the handle though.

Tip: apply some silicone spray for smoother movement of the zipper.