The Gaffer's water barrier is compromised, volunteers needed

[The_Gaffer]

Update
Jonathan and myself spent a day on the boat yesterday, removing the water barrier on The Gaffer.  We managed to remove 2/3 of the stuff from the hull using walpaper scrapers.  Hull is still in tip top condition, so no signs of damage
On Saturday will continue to remove the 1/3 thats left.  Then off with all below the waterline fittings, a good sanding down of the gelcoat...thorough wash down with soap and water, good clean wipe with a special liquid spirit, and proceed to apply West System barrier coating again.
Jonathan spoke to a local professional about possible reasons why this happened in the 1st place, and the guy suggests that:
1. West System epoxy should have been applied once the Gelcoat had cured and not when it was still tacky.
2. The Gelcoat may have been contaminated and thus prevented a perfect bond with the WS epoxy
3. When I originally applied the 1st of 6 coats of epoxy, I mixed in a colouring additive with the 1st coat to enable me to differentiate between the epoxy (which is clear) and the gelcoat (white).  This additive, which is a west system product also, might have prevented the epoxy from bonding with the gelcoat
Meantime, we did take some pictures of the barrier peeling off, which I'll send to West Systems together with the facts when I applied the original epoxy barrier to get their valued opinion on how not to repeat this saga

[The_Gaffer]

Wrote to West Systems in the UK and already received a response.  This is what I call customer service.  Nothing but the best for the best

HI Joe,

Thank you for sending the pictures and the film.

We must ask you exactly what the first layers of coating were?
It looks to me as if there is no bond in these white layers of coating
in which case we must establish whether they are all WEST SYSTEM.

If you are able to send us a sample of the peeled Epoxy we can then
analyse it in our laboratory and understand more.
We only require a small piece in an envelope.

You said on the phone you applied two coats of gel coat and then the six
layers of epoxy
If this gel coat was a polyester based product which was not fully cured
before the application of the epoxy then here may be where the problem
is.

We trust that this information meets your requirements and if you need
any further information please do not hesitate to contact us.

Regards,

Philip Aikenhead.
Technical / Marketing Assistant.
Wessex Resins & Adhesives Limited.

Needless to say, I'll be poping down to the boatyard today to collect a sample of the removed layers and send it by post ASAP.  Will keep you all informed on the story as it develops!

[skip]

Wow impressive stuff and serious customer service.

Alot of the osmosis barrier protection products recommend that a new hull has cured for at least 1 month before application, not sure about West Systems but looks like the case as well.

Keep us posted.

[The_Gaffer]

Another response, this time by West Systems in the USA.  West Systems should be very proud of its customer service dept, its second to none!!

Joseph:
The gel coat that you applied just prior to applying our epoxy- was it polyester gel coat? If it was, I think you will find the adhesion problem will be the point where the epoxy met the ?still tacky? polyester gel coat. Epoxy cures fine over tacky gel coat but the gel coat will not continue to cure under the epoxy. So my guess is that this is the layer where the lifting has occurred. I?m actually surprised that it stayed attached so long.
When polyester gel coat is removed from a fiberglass boat in preparation for barrier coating with epoxy, we recommend applying the epoxy directly to the abraded fiberglass laminate rather than applying polyester gel coat first. This is because epoxy adheres better to sanded fiberglass laminate than the gel coat does and because polyester gel coat will not finish curing in the presence of epoxy.
Once you finish peeling away the epoxy barrier coats be sure to abrade the gel coat aggressively (removing it completely would be best) and make sure you give the hull time to dry well before applying the epoxy barrier coats.
I hope this information has been helpful.

Best regards,
Tom Pawlak
Technical Service

It seems that the problem lies with the fact that I used a polyester based gelcoat.  Both technical services centres are agreeing that the use of polyester gelcoat caused the bonding problem.  My best option now is to remove the remaining WS epoxy barrier left, sand down the gelcoat, and start applying the West System epoxy again.

[skip]

Interesting learning experience for all this one as I think most gelcoats one purchases are polyester based, so it seems allowing it to fully cure for an extended period of time is necessary though I don't think most of us would have known that.

How thick do you reckon the gelcoat that you applied is? Are you going to sand with a rotary sander or have it sandblasted off? If using a rotary sander be careful to maintain the shape of the hull especially where you have strakes etc.

Also good to know that whenever there appear to be gelcoat issues, manufacturers of anti-osmosis systems recommend removing the gelcoat in the area where the anti-osmosis system will be applied. They also stress alot the need to ensure that once removed you allow sufficient time for the exposed laminate to dry after a thorough washing/cleaning with the appropriate liquid.

[benri]

great customer support from West Systems! My 2p worth is take your time to do it Joe and don't rush the procedure. I think I understand you'll be dieing to launch again but have some patience.... On the other hand we can look at the bright side and might have a couple of extra alungi :-)

[shanook]

yeah benri make him stay on land as much as possible so we can catch some before he comes over eh...........yea Joe dont rush it, its better if u let the summer sun of August dry the boat........

[ramio]

Well thanks to the info above, the line I'm thinking of taking looks like a good one.

excellent costomer service!

[camkev]

Good one benri 

[skip]

Guys this is what the forum is all about. Sharing knowledge and experience with each other so that we can all learn and benefit

[The_Gaffer]

An Update.
Well, The Gaffer underwent a sodablast to remove the remaining epoxy from the hull.  This revealed some slight pitting of the hull, which for a 31yr old hull, is very normal.  No osmosis blisters were found,  A surveyor's test was carried out to establish the humidity level of the hull, this turned out normal.  We did this test to establish 2 points. 
(1) That no seawater had penetrated the barrier,
(2) before work can start on the hull, the hull must be absolutely dry, i.e. registering about 2-3% humidity level.

So yesterday, I filled in all the pit holes with west system low density filler mixed with epoxy, and also smoothed out the uneven surface left over by the sodablast using the low density paste.  Now on Tuesday, I'll sand down the excess filler using 80 grit sand paper, and fair off the rest of the hull to produce a dull finish and remove the glaze from the epoxy. If conditions are right on Tuesday/Wednesday, i.e. Sun is shining, little or no wind, and relative humidity is low, I will apply the 6 barrier coats of west system epoxy. 
In the meantime, on Saturday I'll cut and polish the rest of the hull above water.  The gelcoat on the hull has oxidised to the extent that no amount of polishing can restore the shine back.  So, I'll remove the oxidised gelcoat with 400grit sand paper using an orbital sander.  Then, using 1000 grit sand paper, wet sand the gelcoat to remove the orbital sander's rotating marks.  Buff the gelcoat with G3-G6 compound and finish off with a buffer polish using a teflon based wax-polish system. 
Project is progressing according to plan, and the Gaffer should be in the water by end on May/1st week of June

[robby017]

good luck.......

[benri]

Great news Joe and good luck for the remaining jobs.
No need to rush yourself by the way..... :-) More haste less speed they say.... in September it's still summer :-)

[The_Gaffer]

Thanks Guys.  I admit she's an old boat, but way back in the late 70's they did not compromise on material usage.  She's a fine sturdy boat, built to last a lifetime.  The Trojan F-26 project was undertaken by Whittaker and Bertram in the 70's, and produced over 2,000 boats in this class. In 1969 the needed financial backing came in the form of a buy-out by the Whittaker Corporation. The Trojan acquisition was one of a number of boat businesses that Whittaker bought at that time, with a plan,  ?What GM did for cars, Whittaker were going to do for boats. They were a little ahead of their time.?
The original Trojan Yacht Company of Lancaster, Pennsylvania ended production in 1992. Miramar Marine, later known as Genmar, owner of Carver Boats, purchased the Trojan Boat brand name and assets. Genmar Holdings, Inc., the largest independent manufacturer of recreational powerboats in the world, located in Pulaski, Wisconsin, produces motor yachts with the Trojan name through its Carver Yachts subsidiary.  Carver still produce Trojans, but on in the 44 to 55 foot range. 
There is a modern Trojan 44 footer at the Msida marina, powered by twin Caterpillars.  That boat and mine are the only trojans in Malta.

[benri]

Some great reading The_Gaffer. Interesting history. Nowadays it is a must to compromise on material usage due to increase in prices of raw materials. I doubt we will ever again see the sturdy quality of the "olden days" in cars, boats and all. Did you buy The_Gaffer locally or import her?