dharvard..."Who has mixed up some core-fix material (glass shavings, wood shavings, epoxly"...No No No...Many people think that decks can be fixed this way. This would be the same as adding Marvel Mystery Oil
to the crankcase of car that is blown up.
I did the decks on my 1966 Tartan Blackwatch 37. Here was the procedure...
1) Identify suspected areas by tapping with a hard palastic hammer and magic-marker the areas. Add a few inches all the way around this area to ensure you are getting everything.
2) Estimate the fiberglass skin thickness by drillin a 'few' 1/4" holes along the cutting line. Send the wifey of gf out for a case of beer
3) Set your skillsaw (with carbide blade) to the skin depth
plus an 1/8". Cut skin. and lift
out(keep this...you are going to replace it). It should come up relatively easy but a few prybars/crowbars may come in useful. From here on in...have a friend help. At least you can both drink beer
and look important.
4) Chisel out the old ply. This will be easier in some ares than others. The past layer skin of ply will probably be apart of the lower skin and will need to be ground away with a 4" grinder with a coarse flap wheel
. Take it down to fresh F/G and be thorough. Drink at least 2 beers to wash down the F/G dust and relieve the itching.
5) If any exsisting ply is damp or wet, tent the area with a tarp and run a fan until it is dry. While waiting, drink more beer.
6) Use Smith&Company penetrating epoxy
on exsisting ply ONLY. Do not use it on the F/G. No beer here as you are now higher than a kite from the penetrating epoxy.
7) Buy Marine
ply ONLY. Don't get cheap
on this part like the builder
did. The thickness has to be equal to or less than the old ply. This is so when you sandwich it back together, it will not sit high. More on this later.
8) Grind the backside of the upper skin that you cut out. Now, Wash everthing with acetone. Again, no beer...the acetone is about to kick in!
9) Using battons made of hardwood about 1" square and upper skin width, place them width-wise across the upper F/G skin allowing only a 1/2" overhang on each side. Place them every 6"-12". Fasten them with a screw a 1/4" in from each edge only and griind any screw poking through. Then, with the 1/2" that hangs over each side, drill a 3/16" through hole. This set-up is to ensure that the old deck sits flush. I know this sounds complicated and you might be a little too high to comprehend this. Find a sober dock member
(good luck) and have him explain it to you.
10) From inside the boat, it will be very obvious where you have cut out. On a sunny day it will be really obvious. Drill 1/8" holes in a grid of 4"s. I am basing this on my experience of a deck replacement area of 2' X 6'. The reason you do this from under is to ensure accesibility with a driver from under. At this point lay tarps below the holes. You will see why. Ok...time for another beer.
11) Make a pattern using 1/8" door skin for a template to transfer to the marine ply. We are trying to get it to fit as close as possible. Once the ply is cut, fit it into place and lay the old skin over top. Ensure that it is a little below flush. If its not, grind raised areas or the ply. THIS IS IMPORTANT. Wash all surfaces with Acetone. From this point on have lots of acetone and paper towels and garbage bags. You got it...no beer with acetone.
12) Using slow kick epoxy(2 hour pot life), coat all surfaces F/G and ply. Let them kick but do not wait more than a few hours afterwards to go on to the next step. Then mix epoxy with micro-ballons to make a paste like material. Coat with a v-trowel the lower deck and underside of marine ply. lay the ply in and begin screwing from 'down under'. Keep tightening the screws in sequence to push the goo around and out. Clean up your mess and call it a day. Call a cab, your not driving!
13) Next day, hopefully sober, fit the old skin and make up some more goo using micro ballons and trowel the upper portion of the ply and lower portion of the upper skin. Do not over do it on the goo. The clean up is a hassel. You may need to use a dead-blow mallet to push the goo out and around. Using screws long enough, fasten old skin down to exsisting deck. The battons ensure a flush fit...you hope! When the skin is down and you are happy with the fit, clean the wet epoxy out of the seam cut. THIS IS IMPORTANT. Call it a day or get more beer and watch the epoxy dry.
14) The next day, remove all screws, upper and lower. This can be a challenge with good epoxy. Using a 4" grinder wheel
, grind out the seam, removing any epoxy. Using F/G rope
and poly-ester resin, fill the seam and eventually fair it out...Now your deck area is finished...Still want to repair decks?