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Post by Hugh Jorgan on Feb 20, 2023 7:48:49 GMT 12
When expoy has cured the chances there is some Amine blush is near inevitable. You need to remove that and any gloss if you want a well bonded long term finish. You can wash the blush off with water and scouring pad like a scothbrite or similar. Rub it dry immediately or it resettles on the surface. The best way to remove the gloss is sanding. Hence I like peel ply, it removes that clean up/prep. If you are using 105 with 205 or 206 and it's not ready to to go after 24hrs you have been visited by Mr Cock Up. The paint chemists and I did a lot of test panels prior to using it on the boats. Cleaning and sanding the expoy was a must. The paint would just not sit on vertical unpreped surfaces, gravity won everytime. Disagree, if you coat the epoxy at the right recoat window time ( to early an you get crazy cracking but stil a 100% bond, to late and mud ceacking and no bond) with a solvent bourne poly amide cured epoxy you get maximum intercoat adhesion through the solveht softening the resin and getting a chemical key. Then you can either sand and top coat for a non critical wotk ( bilges etc) of go again with more undercoats ( wet on print free) to build enough microns o film build to do a final sand for top coat. We typicaly went,... resin - interprotect sprayed ( airless) to 300microns WFT ( depending on cloth used, this 300m is for 600gsm) - sand - then for awesome fullgloss we use perfection undercoat or any polyurethane undercoat , guide coat, sand to 400grit then - AwlGrip.
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Post by Lionel on Feb 21, 2023 9:56:17 GMT 12
Agree with sailor boy. We used this system for years at Careys boatyard in picton.
We Used to use ht9000 and epiglass199 (sanding between) but when the international rep introduced us to interprotect we never sanded ht9000 again.
Sometimes we sprayed the interprotect on 1mm thick to cover uin cloth profile. Always sured and sanded easy.
199 would never build and amine sweted ecery day in summer.
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Post by GO30 on Feb 21, 2023 15:23:31 GMT 12
epoxy over /on epoxy no issues. Its when you try putting polyester over polyester or expoxy over polyester. Expoy over old and well prepared Expoy and Polyester is fine. Polyester over Expoy not so much.
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Post by GO30 on Feb 21, 2023 15:31:52 GMT 12
Agree with sailor boy. We used this system for years at Careys boatyard in picton You 2 are talking professionals in a professional environment and all the professional resourses and gear that comes with that. We're talking a DIY here. Different hourses on different courses Gents.
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Post by Hugh Jorgan on Feb 21, 2023 17:57:45 GMT 12
yes and no.... the pros do know the recoat window timings like a chef kmows a the inner workings of a perfect pavlova.
But this technique is actually very easy and reliable to obtain but not pushed by companies because of..
1. Post the Altex no3 adhesion failures many shyed away from this due to a "Nervous market" and public perception.(and many suppliers still make amine cure undercoats thay swet)
2. The pro's are more careful than a joe blow who cant get back to the job at the right time.
3. The pro's dont like sharing their secrets.
Hey Lionel, Carey"s were one of the first to use this system. Did you work with the painter Shorty Halliday? (90's) He was a greatguy and a guru with an airless!
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Post by Hugh Jorgan on Feb 21, 2023 18:04:29 GMT 12
epoxy over /on epoxy no issues. Its when you try putting polyester over polyester or expoxy over polyester. Expoy over old and well prepared Expoy and Polyester is fine. Polyester over Expoy not so much. Correct. But vinyl ester is a great option instead of epoxy. I have put polyester gel coat (waxed) over epoxy with well cured interprotect in between and so far so good (10 years and no delam) but the boat is stored inside for 80% of the time)
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Post by GO30 on Feb 23, 2023 5:51:50 GMT 12
2. The pro's are more careful than a joe blow who cant get back to the job at the right time. As a purchaser of a yacht, knowingly, thats paint was falling off due to sloppy Pros who were that cocky they thought they didn't need to read the manufacturers specs, I have to disagee with you. Worse, my boat was only 1 of a lot so preety much a shit load of Pros fucked up big time as they were just too cocky.
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Post by Lionel on Feb 23, 2023 14:14:10 GMT 12
Yes sailor boy. Shorty and jim long gone now. G030, not sure the pros were at fault as much as the product was sensitive to post cleaning swettng, a short max ลecoat window, to fine a final sand, and post top coat yellowing beneath to thin a topcoat.
It was a bitch. But for every bad on there were 50 goodies.
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Post by OLD ROPE ๐ on Feb 25, 2023 19:20:59 GMT 12
I'm with G03000.007 the Pros stuffed up a lot of boats.
A mates boat had only 10% delam from his topsides. The rest wร s perfect... Which tells me the paint and system was not at fault.
Both bow sections had adhesion failure and we, with our basic painting knowledge, reckon they didn't wash down these areas .
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