I dont know about any thinners for this sort of resin, but assuming you are going to paint over the resin after it has been applied and smoothed down, then the paint will form the watertight barrier and any possible failings in the waterproof integrity of the resin will have been sorted out.

 

After all, loads of boats are perfectly waterproof for years and years,  even if they have NO resin..just plain wood and filler. 

 

If you have achieved a good standard of finish on the hull..why bother to resin it at all???

I treat mine to a few coats of sanding sealer, which soaks in well and then a bit of homebase undercoat and whatever on top (humbrol or Dulux. Dulux polyurethane paint…much maligned…very tough stuff , great for boats, Takes a while to dry, cant be wet`n`dried like Humbrol)

 

Do many people bother to resin their boats??  answers please (more than the usual 5 or 6 would be nice).

 

Ashley

 

Ah, but is rivetted card more waterproof than porus resin ?????

 

This little figures just visible in your picture really make it..it brings the scale of the thing into being.

 

Ashley

Jeremy

I’d endorse what Admiral Bish has said. Finishing Resin should already be thinned down enough to be used without further thinners. If you’re unsure then just mix up a small amount and thin it with denatured alcohol. If it sets up hard then nothing is going to shift it afterwards. If it doesn’t set off properly then it was a lousy idea!

BTW Ashley – I’ve used both cloth-and-resin and the old-fashioned dope and tissue methods for years. I find that lightweight cloth and resin is better for compound hulls whereas tissue and dope I prefer for simple, hard-chine types like my Swordsman.

DM

Hi ya there Jeremy

I am attaching some pics of my RTTL model which I am currently building and used the method below to cover the hull.

I would advise strongly against thinning epoxy as there is no need to.  The trick of using Z-epoxy is to purchase the cheap artist brushes (you know the ones – the ones from the Pound shop) to stapple the resin into the grain and into the gaps of the planking.

Once this epoxy has dried, rub it back with a wet n dry paper, until you expose the grain of the planking again, but leaving the epoxy in the gaps.

Then recoat with a 2^nd coating of z-epoxy, and when this epoxy has dried, rub it back but not so as you expose the planks.   Then, put your finished coat of epoxy on – rub this back with finer grades of wet n dry – and a sanding block to achieve this desired finish.

Hi Jeremy, I cast model submarines out of casting resin,and the suppliers provided me with a gallon of acetone to wipe resin away from surfaces liable to be damaged I don’t think it is a solvent that I could use to thin resin, but it helps to clean resin offTo make resin a little thinner, I use10 % hardner rather than 8 % , but if you do that, get your skates onbecause it setslightning quickand generates quite a bit of heat in the curing process. just a few % too much, and you would end up with amber resinSometimes for a final coat, I use clear casting resin or Gel coatby brushing it on like paint and when it has set, Igive it a nice gentle rub down with 800 grade wet and drybut sometimes, I can get some 1600 gradewhich is magicon top of that keyed surface, I can use a spray can of car paint, but if you yry that, don’t get any on your acetate windowswhatever you do     practice masking techniques

On the other point, Personally I would not use plain resin on the outside as it might crack if you whack something…its moderately brittle in thin layers on its own….thats where the fibreglass tissue comes in.

 

Peters method has merit in that his hull is reinforced inside and thus is much stiffer so resisting the sort of denting that comes with unguarded moments (not watching what you are doing whilst being near a jetty), for instance.

 

(just to throw in another view)    Ashley

 

Ashley, I have not had a problem with resin cracking on impact, even if it’s not backed up on the inside with cloth. I once accidentally rammed the rock wall of our lake, at full speed, with one of my boats, and all that resulted was chipped paint, the hull was not otherwise damaged – it was built from 1.5mm ply and resin coated on the exterior. However, I have to admit that full speed on this particular boat is not very fast.

Regarding brass portholes, as we sail in salt water I tend to paint, or at least clear coat, any brass, as it reacts with the salt and corrodes quite quickly. I assume that this problem would not occur in fresh water.

Peter.

You might find it very difficult to rub down the resin to a fine finish if you have already fitted the rubbing strips. The problem is getting the Wet’nDry right into the corners. You might also find that the resin gathers into corners and causes runs. If you use epoxy finishing resin then I’d suggest using epoxy adhesive to fit the rubbing strip afterwards.

DM

Oddly enough, I have just had cause to fibreglass/cloth one of my boats..

 

My HMS Glorious, constructed out of best hardboard and pine plank, has been leaking a bit. Mostly i suspect from the shafts, but the hull is persistently showing fine cracking at the pine/hardboard junction, due to the difference in wood expansion rates (considering one is mostly glue!) and so i decided to give it an “armoured belt” of cloth/resin over the centre section to seal up the worse culprits.

 

Hindsight is a wonderful thing, and if i had only known this earlier, I would have continued this up the side somewhat in order to simulate the originals thin armoured belt, but as I have finished the thing now and done all the portholes etc, the fibreglass belt only goes up ti the red-oxide waterline.

 

The hull on this boat is so incredibly strong.. I had it clamped in the workmate while I was power sanding the pine bottom !!

 

The resin  takes some rubbing down, eh?

 

Ashley

That’s the problem with resin – it’s very hard to sand. Even worse if there is glassfibre in it too. That’s whay I prefer conventional contractuion using traditional materials!

 

Colin

hi there all

 

I have found, if you use a very coarse Oxide sanding paper and a sanding block, the polyester resins and epoxies sand very easy, even if there is a glass matt in the mix.

 

thing is to be careful of – using a coarse Oxide abrasive paper, you can remove a lot of material easily and quickly without realising it.

 

I normally use P.80 and P,60 grade and you will find once you have removed the top surface (in other words the sheen off the top of the fibre glass, you can use a finer grade of wet n dry to finish off.

 

Remember to always use a sanding block of the correct size and shape to prevent sanding hollows in the hull.

 

aye

john