Gelcoat repairs... help!

[Richard B]

After a thorough hull cleaning last weekend, we've discovered a couple of dings that need filling.

A quick browse in the chandlers, and I located some "Plastic Padding" gelcoat filler - is this OK stuff?

How long does it take to cure? Some info I found on the 'net suggests about 20 minutes - so if I use tape over the filler as suggested in Philip's FAQ can I remove the tape after 20 minutes and get sanding straight away?

And if I use the tape as suggested above, am I correct in assuming that it's used with the adhesive side onto the filler?

[eupa]

give it 60 minutes. only sand when it feels like rock

jonathan

[philip]

Richard

I judged when to start working on it by the consistency of what was left on the mixing dish.

My repair was on a spray rail so when it was set and just a bit boingy I removed the tape and used a Stanley knife to trim back a little excess off the edge of the spray rail. By the time I had done this I started to use wet and dry with water.

Tape - sticky side to repair to stop the gel coat moving about

I would try and get a little gel coat from Scorpion so that you get an exact colour match.

Cheers

Phil

[ribraff]

Is the ding on the hull? I would recommend that you go to Scott Bader and buy the appropriate gel coat for your boat, if you speak to Scorpion they will give you the colour code. I don't think you'll get an exact colour match with stuff from the chandlery. I would reckon that Scorpion use 49 PA but it would be best to check. You can buy the Gel coat in small quantities.

www.scottbader.co.uk

...or Scorpion may be a ble to send you some!

[Soupy]

What kind of tape do you use please - type, width etc.

[philip]

Originally Posted by Soupy

What kind of tape do you use please - type, width etc.

Masking tape big enough to cover ding. In my case about 1" width.

Must emphasise- I,m not an expert - I've only done this once but it seemed to go well .

HTH

Phil

[Little Blue]

Speaking one non expert to another, I find the subject confusing.

From what Ive been able to find out/summize I think the following is true.

Plastic Gelcoat filler is not gel coat, but does a good job of filling small areas of damge. Just overfill the damage let go off completely and then rub down flat with gradually finer weet & dry.

True gel coat is a liquid that sets by the action of a catalyst in the absence of air.

As its designed to be the first layer in a mould, air is excluded so it sets. If you use it in air as a top coat or filler, to get it to set you can add a special parafin wax this rises to the surface and protects it from air while it sets. I believe that the use of tape is just another way of excluding air that is sometimes used.

Gelcoat is usually white and manufacturers add pigments to get the coulours they want.

If anyones an expert and can add to this or correct me I would be interested to hear from you.

[Daniel TD5]

ive used the plastic padding stuff in white and found it very good

i had a chip about the size of a fifty pence on the keal

just cleaned it up made sure it was very dry mixed it up as the packets says
filled the hole then with a sharp knife cut back down to a finish looks very
good not saying you can,t see it but a very easy repair

dan

[Gav]

Originally Posted by Little Blue

Speaking one non expert to another, I find the subject confusing.

From what Ive been able to find out/summize I think the following is true.

Plastic Gelcoat filler is not gel coat, but does a good job of filling small areas of damge. Just overfill the damage let go off completely and then rub down flat with gradually finer weet & dry.

True gel coat is a liquid that sets by the action of a catalyst in the absence of air.

As its designed to be the first layer in a mould, air is excluded so it sets. If you use it in air as a top coat or filler, to get it to set you can add a special parafin wax this rises to the surface and protects it from air while it sets. I believe that the use of tape is just another way of excluding air that is sometimes used.

Gelcoat is usually white and manufacturers add pigments to get the coulours they want.

If anyones an expert and can add to this or correct me I would be interested to hear from you.

The only time you should be using tape over a repair is if the gelcoat wont stay in on its own, ie if the repair is upside down......

The additive is called styrene wax 4% solution, this leaves the repair in a non sticky state, gelcoat as you rightly pointed out is meant for a mould surface which is free of air, if no wax was added the repair would stay tacky to the touch.

if you want some gelcoat for a repair i can send you some 49PA ready mixed with 4% wax solution

Gav

[codprawn]

http://marinestore.co.uk/Merchant2/m...vc?Screen=SFNT

probably posted before but these seem to have all sorts of usefull stuff - isopon fillers are good and they also have glue for hypalon and pvc.