S2Jimlad
Well-Known Member
Anyone know of an epoxy which can be applied in cold weather? It's for coating ply rather than gluing or laminating.
Thanks.
Thanks.
Cold weather epoxy
- Thread starter S2Jimlad
- Start date
Poignard
Well-Known Member
I don't know of one. I wish I did.
It doesn't seem to have dawned on the manufacturers that just when we need to use epoxy the most, i.e. during winter lay up, their products don't work!
It doesn't seem to have dawned on the manufacturers that just when we need to use epoxy the most, i.e. during winter lay up, their products don't work!
Strathglass
Well-Known Member
Get in touch with SP.
You will be quite surprised at what is now available.
What temperature do you need to go down to?
I am currently epoxying small bits inside my boat in the garden but in very controlled conditions.
Iain
You will be quite surprised at what is now available.
What temperature do you need to go down to?
I am currently epoxying small bits inside my boat in the garden but in very controlled conditions.
Iain
DinghyMan
Well-Known Member
I think Wests standard hardener goes down to 5c which is cool but maybe not cold enough.
A quick google check and 4.5 or 5C seems the minimum for epoxy. I found that using epoxy in the cold for coating plywood just meant it was still sticky after 24 hrs but seemed to have hardened off fully after about 48hrs.
A quick google check and 4.5 or 5C seems the minimum for epoxy. I found that using epoxy in the cold for coating plywood just meant it was still sticky after 24 hrs but seemed to have hardened off fully after about 48hrs.
S2Jimlad
Well-Known Member
I've replaced my bilge keels, so while I'm at it I'm taking below the waterline back to the wood and giving it a coat of epoxy, so a fair area and as for the temperature, ambient.
Strathglass
Well-Known Member
If you intend to use standard temperature setting epoxy then it would be better to build a small 'tent' around the area you intend to epoxy then heat the inside of the tent up to get this area up to a reasonable temperature before starting.
You should also ensure that the epoxy is heated up to about 20 degrees before starting.
All the brushes, mixing sticks and even the mixing bowl should also be at the same tremperature.
When mixing, especially a large quantity, do not use a mug but use an open plate this will help retard the setting process until it has been applied.
Once it is on the hull very slight heat can be applied using a hot air gun at it's lowest setting this will start the setting process but be VERY carefull not to use too much heat or you will destroy the epoxy. You will also find that too much heat may give bubbles on the surface caused by air escaping.
Iain
You should also ensure that the epoxy is heated up to about 20 degrees before starting.
All the brushes, mixing sticks and even the mixing bowl should also be at the same tremperature.
When mixing, especially a large quantity, do not use a mug but use an open plate this will help retard the setting process until it has been applied.
Once it is on the hull very slight heat can be applied using a hot air gun at it's lowest setting this will start the setting process but be VERY carefull not to use too much heat or you will destroy the epoxy. You will also find that too much heat may give bubbles on the surface caused by air escaping.
Iain
S2Jimlad
Well-Known Member
Thanks guy's for the info. I think I'll screen the area off as suggested and try a test patch initially to see how it fairs. I was hoping to be back in the water by April as I'm off to the middle east from july for 4 months..........no problems with the cold there!!
Rgds,
Jim.
Rgds,
Jim.
Avocet
Well-Known Member
I've been fairing a hull over the last few years (replacing failed gelcoat with an epoxy / microballoon mixture). My experience is that if you're working in cold DRY conditions, there's no problem - it just takes longer to go off. In fact, if it gets cold enough, an epoxy and hardener mixture just goes into "suspended animation" until the temperature rises again - whereupon it just carries on with its curing. I think aerospace "pre-preg" epoxy and carbon fibre roll is kept in a freezer until ready for use for this reason.
Unfortunately, if it's cold and DAMP, that's more of a problem. I believe (but don't know for certain if it's true) that the epoxy hardener is MUCH more willing to react with atmospheric moisture than it is with the resin. Therefore all the time it's not cured, the hardener will be using some of itself up with the moisture and NOT with the resin. This will lead to a slight under-cure when the temperature gets back up. I think I see this in batches that have had time to get exposed to damp. If I get a bit of the leftover stuff in the pot once it is dry and try to snap it, it's very slightly "plastic". Whereas if I do the same with some that's set in hot, dry weather, it's MUCH more brittle (but harder and stronger).
Unfortunately, if it's cold and DAMP, that's more of a problem. I believe (but don't know for certain if it's true) that the epoxy hardener is MUCH more willing to react with atmospheric moisture than it is with the resin. Therefore all the time it's not cured, the hardener will be using some of itself up with the moisture and NOT with the resin. This will lead to a slight under-cure when the temperature gets back up. I think I see this in batches that have had time to get exposed to damp. If I get a bit of the leftover stuff in the pot once it is dry and try to snap it, it's very slightly "plastic". Whereas if I do the same with some that's set in hot, dry weather, it's MUCH more brittle (but harder and stronger).
rhumlady
Well-Known Member
The big problem is the colder the conditions the more viscous the epoxy. Trying to apply it even at about 10c is like using thick honey and as the temperature goes down it goes more like treacle.
branko
Well-Known Member
International Gelshild 200.
I did it on 5C.
I did it on 5C.
DownWest
Well-Known Member
For coating ply, Resoltech RE 1010 is great. Works at relativley low temps (says 18ºC but works at 10 or less) and is a simple 1:1 mix. Water based, 1st coat diluted with 1 unit of water, 2nd by 1/2 unit. 3d straight mix. You can even apply it to damp ply. Like all epoxys, if in sunlight, it needs a u-v blocking varnish. No amine blush, can be overcoated up to a week with no sanding. And is compatable with most other epoxys as a primer for gluing.After coating with 3 layers, looks just like good varnish.
In UK www.connexiontechnology.co.uk or just google resoltech for their site (in English)
Andrew
In UK www.connexiontechnology.co.uk or just google resoltech for their site (in English)
Andrew
Poignard
Well-Known Member
I was given a simple tip by a WEST rep.
He said if it's warm enough to wear a T-shirt, it's warm enough to use epoxy.
[Which precludes it's use for most of the year in the UK /forums/images/graemlins/frown.gif]
He said if it's warm enough to wear a T-shirt, it's warm enough to use epoxy.
[Which precludes it's use for most of the year in the UK /forums/images/graemlins/frown.gif]
rwoofer
Well-Known Member
[ QUOTE ]
He said if it's warm enough to wear a T-shirt, it's warm enough to use epoxy.
[Which precludes it's use for most of the year in the UK ]
[/ QUOTE ]
Not if you're a young club loving female from Newcastle /forums/images/graemlins/ooo.gif
Edit: Or Gosport, now I think about it.
He said if it's warm enough to wear a T-shirt, it's warm enough to use epoxy.
[Which precludes it's use for most of the year in the UK ]
[/ QUOTE ]
Not if you're a young club loving female from Newcastle /forums/images/graemlins/ooo.gif
Edit: Or Gosport, now I think about it.