Thought I'd throw this out into the seabreeze community. Had the good fortune recently to be the recipient of a 2012?? Isonic 90 Wood that had sat in a van during one of our stinky hot summer days here in FNQ. Ordinarily, that isnt an issue, except that the bung hadnt be loosened. End result - a perfect looking board topside, however underneath.......was another issue.
Virtually the entire base had delaminated. So, I am now sharing my journey in repairing this board. Not having had a crack at anything like this in my entire life and being somewhat impatient (could cause the odd problem), i gleaned information from fellow GPS team members and Seabreeze post's past to try a put together the most suitable way of getting the board seaworthy once again.
Primary in the back of my mind was going to be weight. As I stated earlier, I havnt done this at all and wasnt sure of really what to expect, except that I was really keen for the girl not to put on to much weight. I said a target of 1000 grams - no more. Weighing here in prior placed her at 6.8kgs on a set of our handy bathroom liars. I think this bodes reasonably well, however, if not, the end weigh in is by far the telling result.
As you can see, we decided to use the criss cross method (as seen previosly in past forums in an attempt to keep the majority of the hull wrapped in its own skin, without having to introduce to much excessive weigh bought on by resin and glass fibre mat. The EPS core itself was still hard as a rock, with only small amounts lifted of with the skin. This left me with a very good base in which to work with. First up, quickly whipped of the grey undercoat. Next job was to inject the resin in underneath the skin and get it as close and beyond the rails as possible to give it the best strength. I decided to drill a series of holes - the same size as the 50mm syringe I was using.
Resin of choice was FGI R180 plus Slow Hardener and QCell filler. Started mixing small batches to start with - no more than 100mm, mixed with QCell untill the resin was pretty much a slowishly running paste(if that made sense?). PS - added slow hardener after I had mixed in the QCell - to the overall volume of Resin/QCell mix. Found, by accident really, that this worked quite well. Allowed me approx 25 mins all up before the hardening really started to take effect. 25 mins may not seem like a long time, but I was very surprised. It is more than enough even for a job like this.Esentailly I injected all the out side hole's first, allowing the mixture enough time (helped along by adjitaing the hull) to really (and hopefully) get into the rail sections. Once they were complete, it was time for the rest of the panels.
Just a quick word of warning to anyone else who may consider giving this a crack (and I would highly recommend it), you dont need to much resin mixed up. I bought a kilo and 200 gms of Slow hardener (Ratio 5:1)thinking Im going to be back. Not the case. Ultimately, I did mix up 800gms of resin all up, but ended up throwing out 200-250 gms I reckon. The over flow out from underneath each of the criss cross panels was more than enough to fill the cuts roughly.
Kids "Wahoo Mats" came in handy. Just prior to adding the weights below to set the skin back in place. Feeling pretty happy.
Covered the entire board in Polyethelyne sheet, same stuff you use when concreting (doesnt stick to the resin and it didn't) and apply just enough weight to slightly squeese out the resin into the joints. Allow to set, dry for 24 hrs. Mmm, beer o'clock.
Next day, into the task of sanding back to excess resin than has dried on the veneer, continue to fill the ciss cross cuts with fresh resin and QCell ( I made this batch into the consistency this time that was quite thick yet easily applied) to a point where you have a lovely smooth base once again. Basicaly I was preparing for a layer of 4oz glass fibre, just to give the hull that final bit of stength back that may or may not have been taken out by the criss crossing.
Filled and sanded.
4 oz glass sheet layed and wetted - decided just to take it to the edge of the rails only. Reasonably confident (i guess time will tell) I managed to get enough resin into the rails on the initial injection phase. Once again on the phase, let it fully set for 24 hrs - just in case.
Fully sanded back and now ready for one of two coats of auto filler. My tip, manage small areas at time. I really struggled, in fact, it didnt happen at all, to get the filler in on the entire hull in on go before the damn stuff went off. Tried varying amounts of hardener but to no avail. In the end it was far simpler just to do small areas at a time and keep mixing small batchs. Now, you dont need much of this stuff. You are only filling the holes left by the resin not completely filling the matting. Very thin skim layers is all. Sand and if required apply final top coat and re sand. This will give you a finish that is smoother that a babies bum. I found that I was aware that I had sanded enough when I could ever so faintly see the base through the filler. My biggest concern was weight, and filler is quite heavy.
Good old SCA Grey Primer/Filler 400gm spray cans (great value - two cans for $9.90). I took some time with this. I think in the end I sparayed 3 times and sanded in btween after each coat was dried. This way you can really come close to achieving the original finish that is somewhat mottled (ability to see some of the veneer through the paint). Then finally SCA Clear Acrylic final coat. Just to give it a lovely smooth finish. All up, buying materials retail - $265.00. Time spent overall - 6 days. Apparently I have to do actual paid work stuff. Satisfaction Rating - OUT OF THIS WORLD
. I would recommend to anyone - just have a crack.
And the best part - I started off with a board weighing in at 6.9kg's prior to the commencement of surgery - she now weighs in at 7.8kg's. An increase of 900gms. Pretty stoked. I guess time and TOW will be the ultimate test of how good this repair is, but overall I believe we have managed to come up with a pretty good compromise between strength and added weight.
FNQBilly
> 9 months ago, 15 Jan 2015
no way.
