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Advisor contents:
 •   BOAT SELECTION
 •   WHEN YOU PURCHASE
 •   YOUR ENGINE
 •   BOATING ADVICE
 •   SAFETY ON BOARD
 •   TRANSPORT & STORAGE
 •   MAINTENANCE & CARE
 •   REPAIR ADVICE
    Your repair kit
  Inflation / deflation alves repair
  Air Leakage repair
  How to do Gluing?
  Pin-holes and scratches repair
  Cuts repair
  Buoyancy tube seams repair
  Fittings and parts repair
  Fiberglass and Gelcoat repair


Your boat is a real thing, and as every real thing it needs to be repaired from time to time. The less care you give to your boat, the more failures happen. The range of possible damage is quite wide: from smallest punctures to fatal destruction. And every kind of problem needs special actions to repair. The more serious the problem is, the more professional repair you need.
Of course, in case of a serious problem it's better to repair the boat at a service station. But in reality the most part of all repairs are minor damages, which can be easily repaired by non-professionals. Using an inflatable it's very important to know how to make small repairs, as there are so many chances for small damages around. So let's try to learn a little how to do it.


Your Repair Kit  

The repair kit is a thing, which should always be with you, when you go boating. The most necessary things are:
 •  An assortment of patches of different sizes - normally you get some from a boat complete set and some from your dealer or distributor. 10-15 different patches are enough. Be sure that the patches you have are made of the same material as your boat (PVC or HYPALON)
 •  A two-component glue (100ml set), which is appropriate to the type of the boat fabric you have: PVC or HYPALON. Check if the volumes with ingredients are full and closed tight. Read and understand the instructions how to use it
 •  A small polyethylene cap (appr. 50ml) for preparing a glue mixture
 •  1-2 middle-size acid brushes
 •  Small scissors, a knife or razor blades
 •  Waterproof sandpaper and masking tape
All these things are very easy to get, just do not forget it!


     Inflation / deflation valves repair  
   
The damage of inflation valves is one of the most typical defects. Problems can be different: the calve cap lost, air leakage through inlet opening, air leakage between the valve body and tube fabric. In most cases the only way out is to change or reinstall the valve. You can do it at a service station or by yourself (in this case you need a especial tool for valve replacement).
To dismantle the valve you must:
 •  STEP 1. Deflate the boat
 •  STEP 2. Squeeze the valve nut through the tube fabric by hand or by any mechanical means (something like vice) gently, without damaging the tube material
 •  STEP 3. Insert the valve tool and screw out the valve body from the valve nut (the nut stays inside the tube) After dismantling inspect the condition of the valve for damages, cracks, deformations. As a rule it's better to take a new one for exchange

To install the valve :
 •  STEP 1. Insert the valve nut inside the tube, or use the old one if it's in a good condition - just clean it
 •  STEP 2. Put some marine sealant onto the valve treads and the surface, which contacts the fabric
 •  STEP 3. Screw up the valve body to the valve nut by hand, and tighten it then by means of a valve tool hard, holding the valve nut through the fabric (same as when dismantling)
 •  STEP 4. Leave the valve for a 24-hour sealant cure
 •  STEP 5. Check the air tightness with the soapy water.



     Air leakage repair  
   
Air Leakage is of the problems of all inflatable boats. The air pressure gives strength and safety to your boat, and to loose it means to loose everything. You have to know:

THERE'S NO INFLATABLE BOAT IN THE WORLD WHICH IS 100% AIRTIGHT ! EVERY BOAT IS LEAKING, AND THE ONLY QUESTION IS HOW MUCH!

How to recognize that your boat is leaking:
 •  IN CASE THE PRESSURE LOSS IS LESS THAN 20% PER 24 HOURS - THE BOAT IS OK, IT'S ACCEPTABLE
Such boat can stay without inflation for 3-5 days.
 •  IN CASE THE PRESSURE LOSS IS MORE THAN 20% PER 24 HOURS - LOOK FOR LEAKAGE
Such boat becomes soft much quicker - in 1-2 days.

Till now the best and most effective way to find the leakage is soapy water.
 •  STEP 1. Prepare the mixture: take 50% of liquid soap and 50% of water and mix them
 •  STEP 2. Inflate the boat hard till maximum pressure allowed
 •  STEP 3. Paint the mixture rich over all the places to be checked
In case there's a leak you will see it immediately: there will be columns of tiny air bubbles
Very often the leak source is very small and it's a real problem to find it. Use the following scheme for search:

INFLATION VALVES => SEAMS CROSSES ON TUBE CONES => ALL CROSS SEAMS => ALL LONGITUDINAL SEAMS => FABRIC SURFACE.

Comments:
- About 50% of all failures with leakages are caused by inflation valves, and the main reasons are: the valve is not closed with a cap, non-tight, wrong or distorted closure, a damaged cap sealing ring, etc. Check it first.
- About 20% of all the leaks are concentrated in seam areas.
- Last 30% are on the fabric surface: all kinds of fabric damages (pin-holes, cuts etc.) and abrasion.
After you've found the leakage - mark it with the permanent marker and clean the area for repair.


      How to do Gluing?  
   
Here are some words about glues in general. First of all the glue you are going to use should be recommended for inflatable boats repairs. You can get it either from an inflatable boats Dealer, Distributor, or from any marine shop.

Depending on the type of the fabric your boat is made of you will need glue for PVC or for HYPALON. They are different. So, choose the right one for your boat and always check it in the glue description before you buy it.

Glue can be one-component or two-component. What is the difference?
One-component glues are mainly for a very common use. They are easier in use than the two-component ones. But the strength of one-component glue joints is not high, especially when the weather is hot.
Two-component glues have the second component, called "hardener". This ingredient stimulates the polymerization of glue, which sufficiently increases the strength and temperature stability of joints.
In this connection the recommendations are:
- One-component glue is applicable for very easy and momentary repairs, when you have no possibility to repair the damage with two-component glue.
- Two-component glue is a preferable one in any case - use it as the main one!

The technology of glue application in case of repair is quite easy:
 •  STEP 1. Locate the place of repair and choose or cut out the proper patch
 •  STEP 2. Prepare the glue mixture: add the exact quantity of a hardener to the glue and mix them hard. The ratio of a hardener is always mentioned in your glue application instructions. In general the hardener ratio is about 4 - 5%: 4 - 5 parts of a hardener to 100 parts of a glue. Use the mixture within 1 hour maximum as it cures quickly
 •  STEP 3. Bound the gluing area on the boat with the masking tape in order to minimize the glue excess
 •  STEP 4. Carefully clean and dry both surfaces to be glued. In case you have a HYPALON boat it's absolutely necessary to rough the fabric and the patch with sandpaper to make the surfaces 100% mat (for PVC it's not necessary)
 •  STEP 5. Apply the first thin layer of a ready mixture on both surfaces and dry them for 20-25 minutes
 •  STEP 6. Apply the second thin layer of ready mixture on both surfaces and dry them until it is tack-free (about 5 minutes)
 •  STEP 7. Take off the masking tape, put the patch onto the previously marked place and press it
 •  STEP 8. Place the ready joint onto any flat and hard surface and press the joint AS HARD AS POSSIBLE using a metal roller or any other hard round thing (a glass bottle, scissors rings etc.)
 •  STEP 9. Leave the ready joint to cure for 2 days without move before you inflate the boat
In case of an emergency repair leave it for 2 hours without move at least, and then inflate the boat till the pressure is less than nominal. In 2 hours the seam reaches about 70% of strength, which can be satisfactory to reach the place of destination driving with care.


     Pin-holes and scratches repair  
   
Pinholes and scratches can appear as a result of abrasion or a direct puncture. As it doesn't seriously damage the fabric core it can be repaired with a single patch outside.
Choosing the patch size, follow the rule: it should be at least 12-15 mm (1/2 inch) bigger than the damaged area as minimum. So, the patch diameter for pinhole should be not less than 25mm (1 inch). A patch for scratches should have the form of the scratch plus 12-15 mm (1/2 inch) around.

     Cuts repair  
   
Through fabric cuts are the serious damages of the fabric core, which sufficiently decrease its strength.
The best way for correct repair is to glue two patches: one from inside, one from outside. In case it's a problem to install the internal patch properly - sew up the cut with nylon (polyester) thread and install only an external patch. The patch size should be 25-40mm (1-1.5 inch) around the damaged place as minimum.
The cuts up to 50 mm (2 inches) can be repaired by a customer using the repair kit materials.
In case of a bigger damage the best way is to repair it by professionals at an authorized service station.

     Buoyancy tube seams repair  
   
Damage of seams is the most serious problem, which may happen. The only place to repair it is the authorized service station. In case of emergency :
 •  Try to put the patches outside to reach air-tightness as much as possible
 •  Give the glue as much time as possible to cure
 •  Do not inflate the tube hard - keep just lowest pressure, which allows to float at a low speed to go ashore
 •  Rerepair the boat at a service station as soon as possible.


     Fittings and parts repair  
   
To glue any fittings or parts on a boat use the standard recommendations for gluing. There's nothing special. The only problem is to choose the right fitting (seat holder, lifting eyes, towing eyes, etc.). In this case it's better to get the advise of the Dealer


     Fiberglass and Gelcoat repair  
   
In case you are an owner of RIB - some words about fiberglass repair. The technology of fiberglass repair is not so easy and professional knowledge and skills are necessary. For this reason we'd like to recommend you to ask the professionals for the repair of the hull damage. With non-professional work you can make the problem even bigger than before.
But if you still want to try - some words about fiberglass in general. Fiberglass is a composition of two main components: polymer resin and glass fiber. For better outlook every fiberglass part is covered by an exterior decoration layer - gelcoat (also a kind of polymer resin). The resin by itself is a liquid, but after adding a hardener it becomes hard irrevocably. Glass fiber works as a reinforcement and makes the composition strong and resilient.
There are two most popular types of resins: epoxy and polyester. The polyester is more usefed in marine industry for boat hulls production, so if you have a RIB - 95% that you have a polyester. It's very important to know the type of resin of your boat before starting the repair, because the different resins are not compatible. So, check it with your Dealer first.

Glass fiber manufacturers make glass of some sorts: rawing (glass fiber wound to bobbins), glass mat (no woven material made of pressed 50-70mm length cut pieces of rawing) and woven glass fabric. Rawing is mainly for industrial machines use, but mat and fabric can be easily used in hand repair. Now just some common recommendations for the most typical defects:
- Gelcoat scratch. If the scratches are not deep (till 0.2mm depth), but you worry about outlook perfection - you can just grind it with the emery papers (grades 800, 1200, 1500) and polish it to mirror with a polishing paste. In case the scratches are quite deep and a gelcoat layer is damaged sufficiently it's better to rough the damaged area, apply a portion of gelcoat (you can get one either from any marine shop or from your dealer - do not forget to check the color !!!), and then grind it to flat and polish it to mirror.
- Gelcoat crack. When you find a gelcoat crack - the first thing to do is to check if it's only a gelcoat crack and the hull body is not damaged. Gingerly gouge the crack area to 4-5 mm wide till you reach the polyester and inspect if the body is undamaged. If the polyester is OK - fill the groove with the gelcoat, and grind & polish after the polymerization.
- Through-hull crack & through-hull hole. Such defects are the most complicated to repair and some special knowledge is needed. So, in case you've found a through-hull crack or a hole - it's better to repair it at any service/repair station by professionals.


    HAVE A PLEASANT & SAFE BOATING !!!
       
     
   
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