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Kinetix Epoxy Issue

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Created by IFocus > 9 months ago, 3 Apr 2022
IFocus
WA, 585 posts
3 Apr 2022 1:58PM
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Looking for advice (Mark0

1st time using Kinetix epoxy and having problems see photo did a fill coat over the lamination and it hasn't adhered in places.

I haven't had this issue before with other brands.

I can run a knife under the fill coat and it comes off.

Question, is it because I didn't scrub the lam before hand?

I did light sand but clearly it hasn't worked.

Thanks






Mark _australia
WA, 23447 posts
3 Apr 2022 6:02PM
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So its only the filler coat - glass has stuck fine?
(In first pic it looks like glass is lifting too)

When did you do filler coat? Lam still not cured (can barely dent it with fingernail) is the best time

airsail
QLD, 1536 posts
3 Apr 2022 8:20PM
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Do some research into Epoxy amine blush. When the epoxy cures some brands can leave a waxy film that the filler won't stick to. Scrub the surface with scouring pad and soap water, solvents don't remove it. Peel ply after laminating and the wax will be removed with the peel ply.

IFocus
WA, 585 posts
3 Apr 2022 6:44PM
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Mark _australia said..
So its only the filler coat - glass has stuck fine?
(In first pic it looks like glass is lifting too)

When did you do filler coat? Lam still not cured (can barely dent it with fingernail) is the best time


Thanks for the reply gents

Lamination stuck no problems, just the filler coat.

Did the filler coat 24 hours after the lamination and used gloves at all stages, as airsail said I am thinking amine blush which I got on the top of the filler coat both top and bottom but didn't notice any thing on the lamination, 1st time I have seen it.

Mark _australia
WA, 23447 posts
3 Apr 2022 7:03PM
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Nup.
If you rub back or clean the lam with anything, then do a filler coat, it will fisheye all over the place. Don't worry about blush (and Kinetix does not blush much anyway)

You need to squeegee your lam well so its rough - the glass is barely wet - then that rough surface is enough for the filler coat to form a mechanical bond with. Dontt touch it with anything after lam. Nothing.
Better yet is as I said do filler coat when its not quite cured, and I know that's hard we don't all have time as recreational fixer-uppers to go look at ti every 30mins to see the perfect window to apply a filler coat thats chemically bonded too

I think perhaps your glass was too wet - glossy all over..... and so after 24hrs it would need intense sanding to get a fill coat to bond

If you do ever have to remove amine blush, pure water only. Nothing else.

Subsonic
WA, 3354 posts
3 Apr 2022 7:09PM
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Amine blush tends to happen when the atmospheric conditions are less than stellar. If you're in perth (not sure how the rest of the state is fairing?) the humidity at the moment has been up quite a bit. I've not been monitoring it too closely, but if you happened to do it at dew point it would explain the peeling.

IFocus
WA, 585 posts
3 Apr 2022 8:00PM
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Mark the bottom lam wasn't great had a few waves in it and runs (cluster f#$k all-round) so sanded it dead flat but the deck was spot on weave nice and tight and sitting up nicely no resin but both sides have the issue.

Thanks everyone looks like I sanding for the next week looking for any thing that hasn't stuck, I was not happy stuck the board in the shed locked the door went off and sulked doing other stuff.

Nothing worse than being an back yard amateur and getting the results to prove it.

Mark _australia
WA, 23447 posts
3 Apr 2022 8:43PM
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No need to sand for a week - and we've all been there. Its a great job apart from that. Happens.
so rip off the bits that are buggered, sand well and clean lots
Then re-do the resin. It will fisheye due to the cleaning (yeah, dumb but hey... )
when the resin is almost cured (thumbnail test a/a) - resin again. It will fill the fisheyes.
May need third application.
Now flat it off ......... its probably well over-full so 80gr in sander.
Then all over with 180/240/400 wet, and you won't see where u fixed boo boos. As long as its the same resin as u used before....

I've just done 3 hotcoats with Kinetix in insane humidty in gero and no blush worth speaking of.

airsail
QLD, 1536 posts
4 Apr 2022 7:49AM
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Nice one Mark, thanks for your advice and experience

Mr Hooper
WA, 154 posts
4 Apr 2022 11:27AM
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If you're laminating with epoxy you should always do a light hand sand with a soft block and 120 grit before applying any type of filler coat.

IFocus
WA, 585 posts
4 Apr 2022 12:18PM
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airsail said..
Nice one Mark, thanks for your advice and experience


+1

IFocus
WA, 585 posts
7 Apr 2022 11:43AM
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Thought I would update and add a confession .

I really hadn't seen any thing like this before about 1/2 of the fill coat on the bottom just peeled off like sun burnt skin on kids in the 60's and 70's

The other 1/2 stuck so sanded the bottom flat again trying to blend all the edges started by hand then with with the orbital and said fu@k it and attacked with the 7"with a couple of burn throughs.. ding repairs making a board... sigh.

Did what Mark said scrubbed with water and nothing else headed to the garage to try another coat.

Confession.
Looked at my mix notes and realized my mix was a cluster to much hardener got the ratio wrong. Wasn't happy Jan just put the new coat on see how it goes.

Thanks again for everyone's input





Mark _australia
WA, 23447 posts
7 Apr 2022 12:47PM
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How much too much? We've all been there...

IFocus
WA, 585 posts
7 Apr 2022 1:04PM
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Mark _australia said..
How much too much? We've all been there...


About 30% or more, some how mixed 43% of hardener to the total mix used instead of 43% of hardener to the resin amount.
i.e. 43% hardener to 100 epoxy by weight.

I could blame the bourbon followed by beers finished off with a bottle of red excuse but before retirement I was a trained instrument tech spent most of my life measuring stuff...hmm

Mark _australia
WA, 23447 posts
7 Apr 2022 4:28PM
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Man - volume. ....... auto paint mixing cups, 2:1 markings can't go wrong (I still have but anyway...)

Gwarn
245 posts
7 Apr 2022 11:42PM
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Scales are cheap and accurate.
no guessing

Mark _australia
WA, 23447 posts
8 Apr 2022 8:01AM
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Nup, by weight its too hard to mix different qty - 43:100 too hard to modify, so you end up always pouring 100ml resin or 50ml resin no matter how much u need = waste

55c for a 300ml mixing cup with graduated sides that you can reuse if you're careful, and 2:1 is much easier maths. 30+15. 20+10 etc.

(and I had too many scales glued to the bench or foggy display due to paint overspray )

Mr Hooper
WA, 154 posts
8 Apr 2022 9:40AM
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Nah, scales all the way. Once you know the quantities of resin you're mixing consistently the numbers stay in your head. 55 cents a cup is a bit steep if you're going through 50 a week!
If you're not such a messy bastard you'll hardly ever glue your scales to the bench :)

Mark _australia
WA, 23447 posts
8 Apr 2022 10:18AM
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Aaahhhh but you leave enough resin in the cup so its exactly on 50ml or whatever, can use again and again and mix paint in it after resin etc :)

I'll plead guilty to messy though

IFocus
WA, 585 posts
8 Apr 2022 5:06PM
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Nice to get the board sanded flat all good





But what is this below had a heap of these run across the board from one side to the other, they sanded out OK ? (in fact thought the Kinetix sanded pretty good) never seen this before.







Mark _australia
WA, 23447 posts
8 Apr 2022 6:28PM
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Where one layer is overlapping another as you couldn't have sanded every last bit off from the previous boo-boo (and you wouldn't want to to either....too hard) - just a thought?

Kinetix does sand easy no additives etc required like that stuff the seppo's love.
BUT leave it a another few days in 30-40 deg and its different story...

IFocus
WA, 585 posts
8 Apr 2022 7:57PM
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Thanks Mark, I got about 1/2 off the rest stuck pretty well

When putting the coat on do you cross stroke or just stroke end to end?

Mr Hooper
WA, 154 posts
8 Apr 2022 8:37PM
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End to end, then cross stroke, then end to end.
Have a look at Fiberglass Hawaii. Lots of very good videos from people that have worked in the industry for many years there.
You have to be very careful asking for advice on forums. Lots of passionate people but quite often bad advice.

Cheers, Hoops

Mark _australia
WA, 23447 posts
8 Apr 2022 10:02PM
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^^ +1

IFocus
WA, 585 posts
9 Apr 2022 12:47PM
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Mr Hooper said..
End to end, then cross stroke, then end to end.
Have a look at Fiberglass Hawaii. Lots of very good videos from people that have worked in the industry for many years there.
You have to be very careful asking for advice on forums. Lots of passionate people but quite often bad advice.

Cheers, Hoops


Thanks Mr Hooper have watched the Fiberglass Hawaii utubes plus others and understand its a long held practice for poly for levelling but have seen comments that for epoxy it can affect the surface tension.

I have done both and haven't really seen a big difference but conscious of not working the epoxy to much hence the question.

Thanks for the reply appreciate it.

IFocus
WA, 585 posts
11 Apr 2022 5:19PM
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So happy ending board finished and tested today goes really well thanks to everyone's input, Cheers






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"Kinetix Epoxy Issue" started by IFocus