Synthetic bags, although relatively new to the piping community, have come a long way in a short period of time.
Originally no more than a synthetic, airtight material, synthetic bags were flimsy under the arm, when not inflated, and were somewhat challenging to strike in and stop. Over the years, bag makers have added a variety of options including hybrid bags that include a thick, hide-like material over the airtight membrane. This gives the bag a solid feel under the arm and provide for better starts and stops.
Review Part 1 and Part 2 for the first steps to working with your synthetic pipe bag. Part 3 covered methods for correcting leaks at the collars. In this post, we cover more extreme measures that you can take to correct unexpected leaks as well as maintaining the zipper found on most modern synthetic pipe bags.
Seams and Collars
If air is leaking at the base of the collar, check and adjust the following items:
- The rubber collars of synthetic pipe bags may begin to break down over time. Exposure to sun, rain, heat and cold will weaken the material. Keep a watch for surface cracks developing in the rubber which can lead to leakage. In most cases, wraps of electrical tape will take care of the problem. (Though, if you've had your bag that long, it might be time for a change!)
- Collars protrude through a hole in the bag material and are glued into place on the inside of the bag. This glue can deteriorate over time. The base of the collar can becomes separated from the bag and become point of air leakage. You can glue it back into place using Goop or Aquaseal (both are available at hardware stores). Before applying the glue, clean the tab of the collar and the surface of the bag (where you will be gluing the collar back into place) with rubbing alcohol. Let the rubbing alcohol dry, then apply a thin layer of glue to both the bag and the tab of the collar, then tape the edges of the collar into place with masking tape. This will prevent glue from seeping out and, potentially, keep you from gluing one side of the bag to the other. Then, clamp the collar into place. Use a small board wrapped in tinfoil as a flat on the inside of the bag. Set the collar on the board, then use a weight on the outside of the bag to hold the collar in place. Both Goop and Aquaseal take 24 to 72 hours to fully cure. Both glues will cure in higher temperatures with lower humidity. You can speed the curing process by applying heat to the surface being glued. Use a handheld hair dryer on low heat and hold it at least six inches from the surface being glued. It will only take a minute of low heat to kickstart the curing process. Make sure the glue is thoroughly cured before using the bag. The glue should be extremely dry to the touch with no residual fumes.
- Seams are typically glued as well. If air is leaking at the seam, these spots can be glued back into place using the same process as one would use for collars.
- It may be necessary to use a patch to glue a collar or seam back into place. You have several options for patches. If you have an old synthetic bag, you can cut a section from it to use that as a patch. You can also purchase wader repair kits at outdoor stores. A wader repair kit will include Gore-Tex (or similar) and Aquaseal.
When you first install a synthetic bag, the zipper should be lubricated. To lubricate, apply a thin bead of lubricant along each size of the zipper. After applying the lubricant, close and open the zipper several times to distribute the lubricant into the tines. Close the zipper and wipe off any excess on the outside.
Lubricating the zipper will help to create an airtight seal. It will also maintain the ease with which you can open and close the zipper. Sometimes leaks can develop around the zipper area. Again, the rubber zipper is glued and/or sewn to the inside of the bag. Time and use can sometimes cause the glue to fail. Using Aquaseal to patch these areas as with collars should solve the problem.