Whitewater Raft Repair 101 Classes
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EXPEDITION RIVER RAFT REPAIR KIT
□ Raft repair kit in waterproof ammo box:
□ Spare tole pin or oar lock
□ Spare oar clip & extra hose clamps
□ Spare valve & valve tool
□ Duct tape roll
□ Hypalon or Vinyl patching material for floor & tubes
□ Small glue (replace glue each year)
□ Latex gloves or rubber gloves
□ Wrenches or sockets for any size bolt you may have
□ Roller hand tool or roller rasp
□ Wire ties
□ Small bottle of Toluene or glue thinner
□ Spare oar stirrup
□ Spare pin sleeves (pvc pipe)
□ Spare bolts with nut for rowing frame
□ Tongue depressors for stirring glue if needed
□ Ball point pen
□ Sharp scissors
□ Water pump pliers
□ Parts for air mattress
Last raft (sweep) carries the rescue and repair gear.
DOWNLOAD > This Raft Repair Kit List
REPAIRING A LEAK
A. LOCATING LEAKS
a. If it is not obvious, you can usually narrow the leak to a chamber. If you don't have a two gallon insecticide sprayer (pressures with a pump) full of soapy water then the next best thing is a Windex bottle with water and a table spoon of dish soap (water doesn't work by itself).Begin by spraying in and around the valves and them move to the seams and lastly the tube material. The soapy residue will detect even the smallest leak. Some leaks are along seams that could be several inches from where you are seeing bubbles. If the valve is leaking, replace it with a spare valve and see if you can clean it and soften the seal with 404 Protectant.
B. REMOVING AN OLD PATCH
a. More often than not, a leak comes from a loose valve or an old patch that was applied wrong. Pulling off an old patch is identical to replacing a broken handle or D-ring. You simply take a heat gun (a hair dryer can work) and wave it over a corner at low heat until you are able to lift the corner with channel lock pliers. Then work the heat gun down the patch until you pull the whole thing off. Be careful not to apply too much heat to one location or it will blister. Using a putty knife to slice old glue helps but be careful.
b. Once it is off you will need to clean the surfaces. If someone left you with a mess, you may need a aggressive buffing wheel. But be extremely careful not to remove too much Hypalon, all you need to do is remove the glue. You can use Toluol, Toluene or Xylene to soften the glue. (Follow directions on the label, wear rubber gloves and wear a resperator) You hope you never have to but if you need to repair the area again you want to have some Hypalon to work with.
C. LOOSE EDGES
a. If you have a loose edge on a footcone, seam tape, handle or D-ring patch and wish to tack it down, pull up on the loose edge until you find good adhesion. If more than ½ of the surface area pulls up easily it will be necessary to completely reinstall the item. A Dremel Tool can get under the edges for sanding to get a clean surface.
D. MAKING PATCHES – Preparing the Surface
a. We suggest you start by putting on a dust mask. And to keep your shop a little cleaner buy a box fan and put a air filter on the intake said to trap the airborne particles. Use a sharp pair of scissors.
b. Use a belt sander to prep bulk material before you cut specific sizes. Use a compass or a tin can to outline various sizes. Sand the patch material one one side before cutting out the patch.
c. Use the "2 inch rule" when determining the size of the patch the outside of the patch should always be two inches from the tear. The rule for an inside patch (prior to the outside patch) is if a tear is more than 2 ft long or the hole is more than 1 inch in diameter. And don't forget to round all the corners to prevent pealing.
d. Use an adjustable Dremel drill with a cone stone (bit #952) to make a ½" outline on the boat side patch. This bit can also be used to taper the edge of patches when you need to. Then use a circular brush sander to buff the remaining interior area. Or sand by hand with a piece of 80 grit paper.
e. TIP Sanding increases the surface area (microscopic fingers) by 10 times. So the fingers that are created bond with a "little bit" of glue. When you apply too much glue it creates a wall between the two surfaces that will easily break down. Most glue failures are due to too much glue or failure to sand all or part of the one of the two sides.
E. PREPARING AREAS TO BE GLUED
a. If you have sanded too much and the base cloth is showing it will require an additional coating of glue to guarantee a good bond.
b. If you have any difficulty keeping the two sides of the tear together prior to applying the patch, use a piece of double sided tape. Place one side of the tape inside the boat directly below the tear then pull at the ends of the tear to align them while pushing it down on the tape. Then you have a hands free closure.
c. Place the patch over the area to be glued and mark a couple of reference points (12,3,6,9 o'clock) for alignment of the patch when the two sides are ready to attach. If they are tacky you will want to land it perfect or it may mean cleaning the glue and starting all over again.
d. After sanding the surfaces wipe the area off with MEK on a damp cloth.
F. MIXING THE GLUE
a. We use a two part MEK base glue, Stabond UK 148 exclusively because it bonds both plastic and rubber. Compared to a one part glue the bond is much strong and the curing time is much faster. In addition you can't use the old Toluene base glues to patch the urethane on the bottoms of rafts without first grinding off the urethane (good luck).
b. Only mix the glue you will need for the patch you are working on, unless you have other work lined up for the next few days. Four ounces will cover approximately one square foot with two coats.
c. Adhesives should be mixed in a container that has some sort of closeable lid we suggest a Mason jar, this prevents the glue from thickening between applications. Mix in a paper cup with a toung depressor for a small quanity you are using now.
d. Check the glue instructions for exact proportions for each of the two parts. The resin (clear) is packaged in a can and the activator is brown and is packaged in a glass bottle.
G. STORING THE GLUE
a. Like all flammables you should have a fireproof cabinet to store them mixed or not. An old amo box or refrigerator is perfect for the job and a great place to lock up your other tools. Use it to refer to store the mixed glue between applications (or when the phone rings) to keep the glue from evaporating. (keep the lid on!).
b. We've found that a Mason jar (plastic jars melt) is great to keep the glue fresh for 3–4 days (another reason to use Stabond Glue).
c. You can re-use the brushes if they are stored in MEK in a jar that has a hole in the lid large enough to slide the brush in. Use aluminum foil to fill any gaps.
H. APPLYING GLUE
a. The application should be so thin you won't see the brush strokes. To accomplish this you'll need to cut the bristles down to about ½ inch with a scissors. This will prevent glue from accumulating of the bristles and give you a firm contact with the patch area.
b. Apply one very thin coat and allow to dry to a no-tacky state, around 20 minutes depending on temperature and humidity. Apply in a circular motion and brush off the edges. The second coat should be in a different direction.
c. Apply the second coat and take ones of two options.
d. OPTION ONE – STICK WHEN TACKY
e. If you do not have a heat gun allow to dry 5–10 minutes and while it is still tacky joint the two sides together where you have aligned them.
f. OPTION TWO – ACTIVATE WITH HEAT GUN
g. Having a heat gun allows you to make them tacky after they have dried. This is especially helpful when you have a near impossible "lay down" of a long tacky patch. You can lay the patch down dry and heat it to a tacky state from the outside. It is also helpful in removing humidity from the glue. And finally if the patch goes on crooked, you can flash it with the heat gun to soften it and reset it. h. TIPS Do not glue if humidity is over 55%. Don't apply glue in direct sunlight. Use and egg timer to remind you about glue time. Date glues and paints on the bottom of the can.
I. COMPRESSING THE PATCH
a. In most cases the patches should be applied on a firm surface so you can use your weight to ensure the two surfaces have made contact. This is particularly true when you have something like a D-ring that has multiple layers of materials fabric and webbing to flatten.
b. Be sure to work any winkles and bubbles to the outside, pushing your hand roller from center to the outside. You may find that a putty knife with rounded corners or dull screw driver works well depending on the situation.
a. You're not finished yet! If you want it to look like it was factory installed, you'll need to clean off the excess glue with a soft nylon brush. It's okay to go over the lines when applying glue but if you want to catch it before it turns brown you need to clean it after rolling it. Wipe the excess glue with MEK, but don't soak it, or it may seep into the edges and loosen them. Next, attach a clean-up wheel to a drill and make sure it doesn't spin into the patch or you'll lift an edge.
b. If you have any excess glue in your jars, let it dry for 24 hours then peal it off and discard.