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West System

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Created by felixdcat > 9 months ago, 18 Sep 2014
felixdcat
WA, 3519 posts
18 Sep 2014 3:19PM
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West System (Epoxy over Strip Plank Cedar) anybody knows about it? Have been told it is better than foam or balsa core but a bit heavier. Anybody has experience in resilience and fix ability? have been looking at yachts made that way!

WA125er
98 posts
18 Sep 2014 3:29PM
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felixdcat said..
West System (Epoxy over Strip Plank Cedar) anybody knows about it? Have been told it is better than foam or balsa core but a bit heavier. Anybody has experience in resilience and fix ability? have been looking at yachts made that way!



Wasn't Walk on the Wildside and all the Inglis boats built that way? Was really popular in the 90s. Certainly no issues if done right but not sure about weight per square Metre vs Foam/Carbon laminate. Balsa fine until you get a laminate puncture...

Ramona
NSW, 7727 posts
18 Sep 2014 6:50PM
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felixdcat said..
West System (Epoxy over Strip Plank Cedar) anybody knows about it? Have been told it is better than foam or balsa core but a bit heavier. Anybody has experience in resilience and fix ability? have been looking at yachts made that way!


It would be my choice if buying. Balsa core is OK in the deck and foam is OK as long as it's above the waterline only. Full foam hulls do provide cheap boats though! I've built one dinghy in 10mm foam and fibreglass with a heavy layup. The foam makes the hull very stiff and quiet but in this case I used foam to meet survey requirements for flotation. My previous yacht had a cedar plywood hull sheaved with epoxy and cloth. This is fine too but the water can penitrate the end grain and joins in the sheets. Cedar strips don't have that problem, the glue line limits the damage and repair is quite easy. The epoxy cedar strip boats have a couple of layups inside the hull making a sandwich construction. Most damage with wooden boats is from the inside of the vessel.

You do not have to use the West system products, any of the quality epoxy products are just as good if not better. I like FGI. 180

LooseChange
NSW, 2140 posts
18 Sep 2014 7:45PM
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felixdcat said..
West System (Epoxy over Strip Plank Cedar) anybody knows about it? Have been told it is better than foam or balsa core but a bit heavier. Anybody has experience in resilience and fix ability? have been looking at yachts made that way!


If weight is an issue you may wish to consider using Paulownia instead of WRC.

Newmo
VIC, 471 posts
18 Sep 2014 8:01PM
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Hey Felix
Paulownia is definitely the go and not WRC, Bote-Cote epoxy is the brand to use as it doesn't have amine blush issues and is an easy 2:1 ratio. it is bullet proof and has great UV stabilization. Paulownia is great to work with, it's a soft wood with a hard wood grain, It doesn't splinter, is easy to work and water doesn't penetrate the grain very far if at all, it doesn't rot and is lighter than WRC.
Cheers Scott

crustysailor
VIC, 871 posts
19 Sep 2014 10:16AM
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Funny you mention West system (my boat is West and balsa core), I thought I was going to set the boat on fire on the weekend.
I was fibreglassing in 2 deck timber blocks for new spin winches.

Everything was fine, I had mixed up 200ml of West, with fast hardener in an icecream container.
Ive done it before, no problem.

Finished glassing one side, about 120ml or so of epoxy still in the container, then I notice it's starting to go off.
Bugger, it's going to waste.
Actually it getting bit warm.
Actually its getting pretty hot.
Ok now it's starting to smoke and melt the icecream container.

It was nearly going to go over the side, but I managed to think for a minute and just picked it up with some pliers and cooled it down, then dumped it in a bucket of seawater.

I know your meant spread it out in a shallow tray, but it 200ml doesn't look too much.
I checked the ratios and it was fine.

Maybe this should have gone in the dumbest thing thread.


theace
NSW, 70 posts
19 Sep 2014 11:18AM
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crustysailor said..
Funny you mention West system (my boat is West and balsa core), I thought I was going to set the boat on fire on the weekend.
I was fibreglassing in 2 deck timber blocks for new spin winches.

Everything was fine, I had mixed up 200ml of West, with fast hardener in an icecream container.
Ive done it before, no problem.

Finished glassing one side, about 120ml or so of epoxy still in the container, then I notice it's starting to go off.
Bugger, it's going to waste.
Actually it getting bit warm.
Actually its getting pretty hot.
Ok now it's starting to smoke and melt the icecream container.

It was nearly going to go over the side, but I managed to think for a minute and just picked it up with some pliers and cooled it down, then dumped it in a bucket of seawater.

I know your meant spread it out in a shallow tray, but it 200ml doesn't look too much.
I checked the ratios and it was fine.

Maybe this should have gone in the dumbest thing thread.




Crusty, As my old tech teacher once said ,there are only two types of fibreglass businesses, the ones that have burnt down and those that are waiting to burn down.

Ramona
NSW, 7727 posts
20 Sep 2014 9:14AM
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Fibreglass gets hot. I have had it burn though containers. I have never noticed epoxy to get hot. So was this a fibreglass resin mixture or epoxy? If your boat is a West system composite construction you don't want to be putting fibreglass resin any where near it.

Ramona
NSW, 7727 posts
20 Sep 2014 9:31AM
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LooseChange said..

felixdcat said..
West System (Epoxy over Strip Plank Cedar) anybody knows about it? Have been told it is better than foam or balsa core but a bit heavier. Anybody has experience in resilience and fix ability? have been looking at yachts made that way!



If weight is an issue you may wish to consider using Paulownia instead of WRC.


Anywhere local we can buy Paulownia? I have bought some from Bunnings previously when it was sold as "Chinese fir".

LooseChange
NSW, 2140 posts
20 Sep 2014 11:16AM
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Ramona said..


Anywhere local we can buy Paulownia? I have bought some from Bunnings previously when it was sold as "Chinese fir".



The sawmill over in Bomaderry behind DIY hardware can get it but don't stock it as a regular item.

Are you sure the stuff you bought from Bunnings was actually Paulownia? It would seem to be too specialised a timber for them. The timber called "Chinese Fir" is actually a Cypress, "Cunninghamia Lanceolata"

LooseChange
NSW, 2140 posts
20 Sep 2014 11:50AM
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Ramona said..
Fibreglass gets hot. I have had it burn though containers. I have never noticed epoxy to get hot. So was this a fibreglass resin mixture or epoxy? If your boat is a West system composite construction you don't want to be putting fibreglass resin any where near it.


There appears to be a lot of confusion among people as to what is what.

1. W.E.S.T. is an accronym that stands for Wood Epoxy Saturation Techinque. That alone should tell you that you should ONLY use epoxy resins when using wood.

2. West System only produce epoxy resins, no polyester resins at all, so if you use their system on wood all will be well.

3. West produce several different types of hardner which vary the pot life of the mixture, use the one appropriate to your needs.

4. Always mix more than what you are going to need. Mixing only small lots increases the chance for error as a small mixing error can create a huge percentage difference in the final mix ratio.

5. Epoxies have hardners and Polyesters have catalysts. What's the difference you ask? When mixed correctly, epoxy resin will set and that's that, no more reaction. When polyester is mixed correctly the catalyst will keep on catalysing even after the mixture has set, that is, the reaction goes on forever, meaning the resin will become more and more brittle.

6. Both types of resins can be mixed so incorrectly that they will have a violent exothermic reaction, that's why it is better to mix more than you need.

7. A resin that is slightly over cured is infinitely better than a resin that is under cured, although a resin that correctly cured is infinitely better yet.

8. Fibreglass does not burn or get hot, only the resin does that. Fibreglass is the mat that imparts strength to the structure and holds the resin in place. Fibreglass is exactly the same stuff that the windows in your house is made from.

Happy glassing, and work safe

Ramona
NSW, 7727 posts
20 Sep 2014 6:47PM
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Nit picker! You should probably add that West don't make their own resins too, they just mix from stock like most other resin resellers. I was out at the Flinders estate Friday to buy some FGI epoxy. They now "make" their own on site and label it with a different label, same product though. Picked up some carbon fibre/glass tape, seems about 50:50. Half the price of straight carbon and wets out easier. Giving it a try at the moment.

LooseChange
NSW, 2140 posts
20 Sep 2014 7:20PM
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Ramona said..
Nit picker! You should probably add that West don't make their own resins too, they just mix from stock like most other resin resellers. I was out at the Flinders estate Friday to buy some FGI epoxy. They now "make" their own on site and label it with a different label, same product though. Picked up some carbon fibre/glass tape, seems about 50:50. Half the price of straight carbon and wets out easier. Giving it a try at the moment.


I wasn't having a go at you (yeah right) but it seemed that your post was a good opportunity to clear up some of the confusion i have seen on here regarding the differing resins.

How is the 50:50 oriented, both weft and warp or warp or weft only?

HG02
VIC, 5814 posts
20 Sep 2014 7:31PM
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First attempt at using epoxy today 5 to 1 . it was slow to go off the hardener said 30 minuets . From what I read on line it was recommended for old fiber glass boats also it . The article stated that fiber glass resin on old fiber glass boats was not a good idea as it wont bond well ?

Ramona
NSW, 7727 posts
21 Sep 2014 9:12AM
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LooseChange said..

Ramona said..
Nit picker! You should probably add that West don't make their own resins too, they just mix from stock like most other resin resellers. I was out at the Flinders estate Friday to buy some FGI epoxy. They now "make" their own on site and label it with a different label, same product though. Picked up some carbon fibre/glass tape, seems about 50:50. Half the price of straight carbon and wets out easier. Giving it a try at the moment.



I wasn't having a go at you (yeah right) but it seemed that your post was a good opportunity to clear up some of the confusion i have seen on here regarding the differing resins.

How is the 50:50 oriented, both weft and warp or warp or weft only?


Both, looks like a checker board. Trying to find it on eBay but no joy yet.

Ramona
NSW, 7727 posts
21 Sep 2014 9:28AM
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HG02 said..
First attempt at using epoxy today 5 to 1 . it was slow to go off the hardener said 30 minuets . From what I read on line it was recommended for old fiber glass boats also it . The article stated that fiber glass resin on old fiber glass boats was not a good idea as it wont bond well ?


5 : 1, sounds like FGI. It has a working life of at least 30 minutes but goes off over 2 or 3 hours though you can speed it up with a hot air gun. Hard after 24 hours and full strength after about 28 days.

Best investment you can make is a small set of digital scales, about $8 off eBay. Measure by weight and be very accurate. I have a set of jewellers digital scales too I bought for measuring small amounts [half a teaspoon or so] but find the kitchen scales handle tiny amounts well. I just use FGI 180 for everything, laminating or adding fillers for a glue etc. Never seen amine blush.

The shipwrights around here use fibreglass resin on old 'glass but I find epoxy much easier and economical. With all the new reinforcing about now its just brilliant stuff.

HG02
VIC, 5814 posts
21 Sep 2014 11:24AM
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Ramona said..


HG02 said..
First attempt at using epoxy today 5 to 1 . it was slow to go off the hardener said 30 minuets . From what I read on line it was recommended for old fiber glass boats also it . The article stated that fiber glass resin on old fiber glass boats was not a good idea as it wont bond well ?




5 : 1, sounds like FGI. It has a working life of at least 30 minutes but goes off over 2 or 3 hours though you can speed it up with a hot air gun. Hard after 24 hours and full strength after about 28 days.

Best investment you can make is a small set of digital scales, about $8 off eBay. Measure by weight and be very accurate. I have a set of jewellers digital scales too I bought for measuring small amounts [half a teaspoon or so] but find the kitchen scales handle tiny amounts well. I just use FGI 180 for everything, laminating or adding fillers for a glue etc. Never seen amine blush.

The shipwrights around here use fibreglass resin on old 'glass but I find epoxy much easier and economical. With all the new reinforcing about now its just brilliant stuff.



I have some syringes with the measurements on the side and used that for the resin and hardener . Im not sure what Ive done but its getting removed and starting again damit . Perhaps I did'nt mix it throughly on the first batch .
I did fill in the old start panel on the stern of the boat that worked out well and had hardened up nicely also filled in the old compass hole as it had been leaking and filled it with what looks like car bog
Ill bring it back to standard with out that protrusion


pumpnjump
WA, 265 posts
21 Sep 2014 10:05AM
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LooseChange said..

Ramona said..
Fibreglass gets hot. I have had it burn though containers. I have never noticed epoxy to get hot. So was this a fibreglass resin mixture or epoxy? If your boat is a West system composite construction you don't want to be putting fibreglass resin any where near it.



There appears to be a lot of confusion among people as to what is what.

1. W.E.S.T. is an accronym that stands for Wood Epoxy Saturation Techinque. That alone should tell you that you should ONLY use epoxy resins when using wood.

2. West System only produce epoxy resins, no polyester resins at all, so if you use their system on wood all will be well.

3. West produce several different types of hardner which vary the pot life of the mixture, use the one appropriate to your needs.

4. Always mix more than what you are going to need. Mixing only small lots increases the chance for error as a small mixing error can create a huge percentage difference in the final mix ratio.

5. Epoxies have hardners and Polyesters have catalysts. What's the difference you ask? When mixed correctly, epoxy resin will set and that's that, no more reaction. When polyester is mixed correctly the catalyst will keep on catalysing even after the mixture has set, that is, the reaction goes on forever, meaning the resin will become more and more brittle.

6. Both types of resins can be mixed so incorrectly that they will have a violent exothermic reaction, that's why it is better to mix more than you need.

7. A resin that is slightly over cured is infinitely better than a resin that is under cured, although a resin that correctly cured is infinitely better yet.

8. Fibreglass does not burn or get hot, only the resin does that. Fibreglass is the mat that imparts strength to the structure and holds the resin in place. Fibreglass is exactly the same stuff that the windows in your house is made from.

Happy glassing, and work safe


Great a response with knowledge, I was going to reply a couple of nights ago, but I had had a few beers and my wife said I would write something embarrassing, by the way Ramona, "fibreglass resin" on old boats, is just resin, but generally polyester resin or slightly higher tech vinylester, as Loosechange said, fibreglass is the reinforcement whether chopped strand, woven rovings or any other weave. Whose a nitpicker now :)

Ramona
NSW, 7727 posts
21 Sep 2014 7:04PM
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Select to expand quote
Ramona said..

LooseChange said..


Ramona said..
Nit picker! You should probably add that West don't make their own resins too, they just mix from stock like most other resin resellers. I was out at the Flinders estate Friday to buy some FGI epoxy. They now "make" their own on site and label it with a different label, same product though. Picked up some carbon fibre/glass tape, seems about 50:50. Half the price of straight carbon and wets out easier. Giving it a try at the moment.




I wasn't having a go at you (yeah right) but it seemed that your post was a good opportunity to clear up some of the confusion i have seen on here regarding the differing resins.

How is the 50:50 oriented, both weft and warp or warp or weft only?



Both, looks like a checker board. Trying to find it on eBay but no joy yet.


I made a bulls up! Its warp only. Popped it off the mould this afternoon and it looks damn good. If your looking for a clear finish and want that carbon look its impressive. I'm painting this job so I will probably use strips of carbon and wet through FIBREGLASS cloth straight over the carbon for the rest of the reinforcing.

Ramona
NSW, 7727 posts
21 Sep 2014 7:20PM
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Select to expand quote



I have some syringes with the measurements on the side and used that for the resin and hardener . Im not sure what Ive done but its getting removed and starting again damit . Perhaps I did'nt mix it throughly on the first batch .
I did fill in the old start panel on the stern of the boat that worked out well and had hardened up nicely also filled in the old compass hole as it had been leaking and filled it with what looks like car bog
Ill bring it back to standard with out that protrusion



Syringes and pumps are a waste of time. Digital scales are more accurate. Set the scales to zero after placing your container and just carefully pour the stuff.

If your using epoxy as a filler, mix the product well first before adding whatever you are using as a filler. Whatever you do, do not add extra hardener. If your laminating always do it in the shade.

HG02
VIC, 5814 posts
21 Sep 2014 8:06PM
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Ramona said..




I have some syringes with the measurements on the side and used that for the resin and hardener . Im not sure what Ive done but its getting removed and starting again damit . Perhaps I did'nt mix it throughly on the first batch .
I did fill in the old start panel on the stern of the boat that worked out well and had hardened up nicely also filled in the old compass hole as it had been leaking and filled it with what looks like car bog
Ill bring it back to standard with out that protrusion



Syringes and pumps are a waste of time. Digital scales are more accurate. Set the scales to zero after placing your container and just carefully pour the stuff.

If your using epoxy as a filler, mix the product well first before adding whatever you are using as a filler. Whatever you do, do not add extra hardener. If your laminating always do it in the shade.


Ill do that this week Ramona cheers I guess it will be still the same 5 to 1 in weigh grams not ML

LooseChange
NSW, 2140 posts
21 Sep 2014 8:32PM
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HG02 said..

Ill do that this week Ramona cheers I guess it will be still the same 5 to 1 in weigh grams not ML


That would only hold true if the SG is 1, which I don't think it is.
Best you ring the resin supplier and ask them for a mix by weight ratio

HG02
VIC, 5814 posts
21 Sep 2014 8:45PM
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Select to expand quote
LooseChange said..

HG02 said..

Ill do that this week Ramona cheers I guess it will be still the same 5 to 1 in weigh grams not ML



That would only hold true if the SG is 1, which I don't think it is.
Best you ring the resin supplier and ask them for a mix by weight ratio


Ill ring them for sure Its been going OK since my first batch ,maybe I miss counted (not enough hardener) which is one if the reason Id like to weight it instead.
Ive left that port light for now and have strengthen all the other port lights inside the cabin. Once that all finished Ill epoxy the out sides and tidy up.
I was not sure how to clean off the old epoxy on that port light Ive removed all the fiberglass mat but there is still resin from that batch. Any idea on what to use acetone may be and sand down after?

LooseChange
NSW, 2140 posts
21 Sep 2014 9:14PM
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HG02 said..


Ill ring them for sure Its been going OK since my first batch ,maybe I miss counted (not enough hardener) which is one if the reason Id like to weight it instead.
Ive left that port light for now and have strengthen all the other port lights inside the cabin. Once that all finished Ill epoxy the out sides and tidy up.
I was not sure how to clean off the old epoxy on that port light Ive removed all the fiberglass mat but there is still resin from that batch. Any idea on what to use acetone may be and sand down after?


The place you bought the resin from will have either solvent or thinners, both of which will clean up the remaining resin.

HG02
VIC, 5814 posts
21 Sep 2014 10:23PM
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Select to expand quote
LooseChange said..


HG02 said..

Ill do that this week Ramona cheers I guess it will be still the same 5 to 1 in weigh grams not ML




That would only hold true if the SG is 1, which I don't think it is.
Best you ring the resin supplier and ask them for a mix by weight ratio



Another way would be to weight out 50 Ml and 10 ml
or even 100ml and 20 ml might be more accurate and use the results as a weight. .
Today I used a lot of tri-actual fiberglass very heavy duty I been wetting out on a piece of sign age board ( same as my cabin roof)and rolling both sides , then rolling in place seems to work OK and will be really strong
Looks some thing like this below



LooseChange
NSW, 2140 posts
21 Sep 2014 11:27PM
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Select to expand quote
HG02 said..

Another way would be to weight out 50 Ml and 10 ml
or even 100ml and 20 ml might be more accurate and use the results as a weight.

Today I used a lot of tri-actual fiberglass very heavy duty I been wetting out on a piece of sign age board ( same as my cabin roof)and rolling both sides , then rolling in place seems to work OK and will be really strong
Looks some thing like this below




Please re-read my post above about mixing small quantities, the margins for error are much tighter, especially using a brand that requires a 5:1 ratio.

Tri-axial is no harder to work than any other cloth, just be certain that you work the compactor back and forth to make sure there is no air trapped in it and you only use the minimal amount of resin.

HG02
VIC, 5814 posts
21 Sep 2014 11:46PM
Thumbs Up

Select to expand quote
LooseChange said..

HG02 said..

Another way would be to weight out 50 Ml and 10 ml
or even 100ml and 20 ml might be more accurate and use the results as a weight.

Today I used a lot of tri-actual fiberglass very heavy duty I been wetting out on a piece of sign age board ( same as my cabin roof)and rolling both sides , then rolling in place seems to work OK and will be really strong
Looks some thing like this below




Please re-read my post above about mixing small quantities, the margins for error are much tighter, especially using a brand that requires a 5:1 ratio.

Tri-axial is no harder to work than any other cloth, just be certain that you work the compactor back and forth to make sure there is no air trapped in it and you only use the minimal amount of resin.


Thanks loose change I have been very diligent concerning the wet out and compactor . I already had one set back yesterday so I don't need any more.
I have been using a initially fiberglass resin and copped mat then some medium mat cant remember the weight both the mat and the cop strand are reasonably heavy weight .Then changed over to epoxy and more meduim mat today was epoxy with three tri actuals over the top over everything . it all went well and Im happier than yesterday. Might see if I can get a few days off work RDO and some holidays and finish the fiberglass and epoxy off and build the out side up with some filler and a long board. I'm going to paint the deck and cabin sides( sort sort of off white Cream with a darker cream on the non skid) when its all done.
The gel coats a little thin in places which you would have to expect after 30 plus years.
Also I'm moving the port lights forward 300 cm to make room for the head on the port side .
Initially I was regretting doing all this but its starting to feel right now.

Ramona
NSW, 7727 posts
22 Sep 2014 9:06AM
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FGI epoxy is 5:1 either by weight or capacity which makes it easier to handle and more accurate to mix.

Do not use CSM with epoxy. I'm sure you are not. The binder does not dissolve with epoxy. I don't do anything with polyester now and sold off my rolls of csm. Cheaper and easier to stick with epoxy for the size jobs I do now.

QLDCruiser
QLD, 160 posts
22 Sep 2014 9:35AM
Thumbs Up

Select to expand quote
HG02 said..

LooseChange said..


HG02 said..

Ill do that this week Ramona cheers I guess it will be still the same 5 to 1 in weigh grams not ML




That would only hold true if the SG is 1, which I don't think it is.
Best you ring the resin supplier and ask them for a mix by weight ratio



Ill ring them for sure Its been going OK since my first batch ,maybe I miss counted (not enough hardener) which is one if the reason Id like to weight it instead.
Ive left that port light for now and have strengthen all the other port lights inside the cabin. Once that all finished Ill epoxy the out sides and tidy up.
I was not sure how to clean off the old epoxy on that port light Ive removed all the fiberglass mat but there is still resin from that batch. Any idea on what to use acetone may be and sand down after?


I've used Bote-Cote epoxy, which as an earlier poster said is 2:1 by volume. A different ratio applies if making up by weight, because the two components don't have the same SG. I don't recall the details (except that one of the numbers is 38, not much use without the other!!) - just ask the distributor when you buy it - or I'm sure you could find it online.

felixdcat
WA, 3519 posts
24 Sep 2014 8:42AM
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Thank you guys for the "expert" comments, I am not building but looking at buying a Ross780 West cedar stripped construction and want to know the pros an con. I had a plywood made Farrier and found it a bit fragile, did a couple of holes in it. It was easy to fix, maybe easier than fibre glass.
I heard that cedar is rot resistant but doesn't like fresh water. How easy to fix is it?

felixdcat
WA, 3519 posts
24 Sep 2014 9:12AM
Thumbs Up

Select to expand quote
LooseChange said..

Ramona said..
Fibreglass gets hot. I have had it burn though containers. I have never noticed epoxy to get hot. So was this a fibreglass resin mixture or epoxy? If your boat is a West system composite construction you don't want to be putting fibreglass resin any where near it.



There appears to be a lot of confusion among people as to what is what.

1. W.E.S.T. is an accronym that stands for Wood Epoxy Saturation Techinque. That alone should tell you that you should ONLY use epoxy resins when using wood.

2. West System only produce epoxy resins, no polyester resins at all, so if you use their system on wood all will be well.

3. West produce several different types of hardner which vary the pot life of the mixture, use the one appropriate to your needs.

4. Always mix more than what you are going to need. Mixing only small lots increases the chance for error as a small mixing error can create a huge percentage difference in the final mix ratio.

5. Epoxies have hardners and Polyesters have catalysts. What's the difference you ask? When mixed correctly, epoxy resin will set and that's that, no more reaction. When polyester is mixed correctly the catalyst will keep on catalysing even after the mixture has set, that is, the reaction goes on forever, meaning the resin will become more and more brittle.

6. Both types of resins can be mixed so incorrectly that they will have a violent exothermic reaction, that's why it is better to mix more than you need.

7. A resin that is slightly over cured is infinitely better than a resin that is under cured, although a resin that correctly cured is infinitely better yet.

8. Fibreglass does not burn or get hot, only the resin does that. Fibreglass is the mat that imparts strength to the structure and holds the resin in place. Fibreglass is exactly the same stuff that the windows in your house is made from.

Happy glassing, and work safe


Thank you, very informative, I take that it is then not a good idea to use epoxy to fix damages on a WEST system hull!



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"West System" started by felixdcat