Repairing Patches:
Materials needed:-
2903 pvc primer and cleaner
3026 two part adhesive
Paint brush (cut down to 20-25mm bristle.)
Lint free cloth
Pvc material
Masking tape
Polythene
Knife handle or rounded piece of hardwood

IMPORTANT:
Before you start any glueing please note:- your workplace needs to be well ventilated, warm and dry. If the air is humid don't try to use the adhesive as it will bloom. Do not use a gas fire or naked flame heat source as the solvents are highly flammable. Do not use the adhesive if it has been mixed for more than 4 hours.

If the damage to your tube is more than 15mm in any direction an inside patch needs to be applied. The procedure is the same as for an Outside Patch but is made more difficult because you are working on the inside of the tube.

INSIDE PATCH
1. Mark out and cut your material to size. This should be big enough to cover the damage plus 30mm on every side. Make sure that all the corners are rounded.

2. Using your cloth wipe the surface of the patch and the tube that is going to have the adhesive on with the 2903 solvent. Allow the solvent to flash off and wipe over again. The surface should become tacky. Allow to flash off. If you apply the adhesive too soon it will bloom (turn slightly white) the adhesive will need to be removed and new adhesive will have to be applied.

3. Mix half of the adhesive (3026 two part adhesive) as directed on the tin. Brush onto the surface thinly, the surface should look wet. Allow the adhesive to dry for at least 30 minutes.

4. Brush on a second coat of adhesive on both surfaces. With the inside patch lay a piece of polythene onto the adhesive, so it can be rolled up and put through the hole. Place inside the tube and put into position, remove polythene. Work one side down with your knife handle, pressing hard. then work the other side. Work from the middle to the outside of the patch. You must make sure that there is no air trapped between the surfaces. Please note:- the adhesive is a contact type, as soon as it touches the other surface it will stick. Make sure that the patch is in the correct position before the surfaces come into contact.

5. Leave to dry for at least six hours.

6. When dry pump up the chamber and check for air leaks. The inside patch must be practically air tight.

OUTSIDE PATCH
7. Prepare the outside of the tube and your outside patch. Using the masking tape to tape around the patch leaving about a 3mm gap to allow for stretch in the material.

8. Wipe with the solvent. second wipe the solvent. Mix the rest of the adhesive. Apply first coat of adhesive, leave for 30 minutes, apply second coat of adhesive.

9. Put down the patch and rub down from the centre out with your knife handle. Check that all the edges are stuck down. You must make sure that there is no air trapped between the surfaces. Remove the tape and rub off any excess adhesive. If the adhesive is left on it will turn brown.

If the adhesive has flashed off so it's not sticking, gently warm the area with a hair drier or a hot air gun and push down with your knife handle.

Acknowlegement:
Information courtesy of Polymarine, supplier of inflatable boat spares and accessories, visit: www.polymarine.com   Note: Polymarine can supply inflatable boat fabrics by the metre length for patches or larger repairs along with solvents and adhesives.

June 2007