A friend managed to severely crease / almost snap in half his 11' x 27" x 4.25" Surftech Laird SUP. He was surfing the Severn Bore when the board became jammed between the river bank and a steel post in the water a few feet away. The force of the current bent the board around the post. It was probably only the rubber deck pad that stopped the board being completely severed.
I offered to repair it even though I have not done anything on a Surftech of such magnitude. I did research on The Board Lady website - very informative - and the Surftech one as to how the board is constructed.
I have made a start and have been taking photos so would to share the project here.
First left the board upside down in the sun for several days to drain out any water and then turned it over to dry out any moisture.
Then started work on it in the garage. The goal was to attempt to restore the orginal material as closely as possible and thus restore the strength, flex, warertightness and even the paintwork without adding any significant weight.
I put the board on trestles and supported it under the crack at a height the I felt restored the original rocker. Ideally I would have tried to get the nose and tail rocker measurements but might just use my eye in absence of such information.
Using a jigsaw I cut out a strip of the bottom skin approximately two inches wide either side of the crack and cut away all torn and damaged material.
Using a 80grit disc on a drill I sanded a sloping scarf about 8 inches either side of the cut. Produced a a hell of a lot of nasty dust so a mask was necessary. The sanding revealed the various layers that the board was made up of and I would attempt to restore:
“Fused cell waterproof core” to quote Surftech. EPS foam core - no stringer
Fibreglass cloth with epoxy resin.
“Cellulose fibre composite” - I will be using 3mm pvc foam
Exterior cloth and epoxy resin laminate
Hotcoat - I plan to add some fairing compound to the resin for a better finish
Because the deck skin was hidden by the rubber pad I was concerned that I could not see if the the crack extended around the whole board. Rather than remove the rubber, risking damaging it and having to glue it back again I decided it would be wiser to remove the foam from the between the cuts I had made and expose the inside of deck. It proved worth while. There were several cracks running from the rails down a few inches that if left could allow water to seep in as it appeared that the rubber is only glued firmly around the perimeter. Found some metal staples sticking up. Dont know what they are for.
Covered the cracks on either side below the rails with small piece of 6 oz cloth and RR epoxy resin. Had some left over so decided to paint the rest of the exposed skin for good measure.
Resin did not take long to dry as I used some left over Kwik Kick and a fan heater.
In hindsight not a good idea due to risk of exotherm meltdown but I have been rushing a bit to make progress over the weekend.
The gap is now ready for filling with replacement foam. At first I thought I would cut and fit a piece of XPS but then thought it better for strength and filling to use polyurethane foam in a can.
I was not concentrating (explaining repair to daughter) when squirting in the foam and added too much. A bit wasteful.
The result looks like a large French bread roll but the gap has been filled.
Once cured I cut off the excessive excess foam with a saw and sanded it down level with the existing foam with a sanding block. There were a few air pocket where the foam had not cured properly so I filled them with some offcuts.
As you will see from the side view there is now a concaved area that will be filled with an epoxy lam/pvc foam / epoxy lam sandwich except for a final fairing layer that will added after to be sanded back to restore the surface curve.
6 oz cloth laminated with epoxy resin. PVC foam placed on top of foam.
This would have an opportunity to do my first vacuum bagging but I am not set up yet. Decided rather to go for the pressure method which I used for making fins which produced good results.
Large sheet of plastic over whole work area. Smoothed out to remove any wrinkles where it stuck to the wet cloth.
I then packed damp building sand on top of the whole area focussing on the concave beneath the pvc foam to force into contact with wet cloth.
Levelled the sand, another sheet of plastic, a sheet of plywood, and finally weights on top, including a bucket of water and the base of one of my shaping stands.
That is as far as I have got to now. It is now drying.
The project at close of play today.
I will leave it to dry now.
The next chance I will get to carry on will be mid week.
TENTATIVE PLAN:
Sand and feather edges of pvc foam.
Fill remaining holes in rails with epoxy fillet.
Apply top layer of cloth and epoxy. Have run out of RR so will be using West System epoxy which I am used to working with for boat building.
Laminate, then when tacky add filler coat with some fillet mix added to aid sanding / fairing.
Glue back loose edges of rubber deck with contact adhesive.
Primer - spray can
Red and yellow colours with spray can.
Clear gloss coat spray.
Polish.
You cant see in these photos but I have put a trestle under the centre of the break and then wedged in a piece of wood to get the appropriate rocker alignment.
After curing overnight I removed everything and sanded back the repair. There was still a dip in the middle so I had to add some more resin and filler, let that cure and then sand it again until I got the area nice and level. There were also some dips on the rails that I filled with fillet mix and then sanded when cured.
After the last picture the board still needed another layer of resin to get the final preparation prior to painting. With experience I reckon I do this in less stages.
Sanded area with 80, 120, 180, 240 grit paper. Cleaned with alcohol. Masked area with tape. Sprayed with clear acyrlic primer in a can, then red as base coat as I did not have white. When dry masked red area and sprayed yellow. Dry. Black lines drawn with Posca pen. Clear gloss acrylic spray paint. Left to dry.
Board now looks like this. Not perfect but the result is far better than I expected. All there is left to do is give a fine sand or polish to the area, glue back the edges of the deck pad and clean the board so hopefully everything blends in..
