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ECV3
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Group: Forum Members
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I have made my first plug (MDF, 2K High Build Primer, 2K Lacquer) and need to know what is the best Release Agent to use with a new 2K covered plug and the Unimould System and can i use Newplast instead of filleting Wax ?. Cheers!
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Dravis
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Group: Forum Members
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Easylease ... 5 -6 coats --- I normally then do a very light polish with EC mould release wax ... but really not needed .. the Unimould gelcoat does not seem to have any fish-eying at all ..
"Sapere Aude"... Dare to KNOW!
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Do not adjust our mind, theres a fault in reality :-)
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Hanaldo
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Group: Forum Members
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Just be careful using semi-permanent release agents and styrene-based gelcoats with your paint systems. Always, ALWAYS do a test with the materials you want to use before committing to the actual part. I've had more than one failure with 2k paint systems and making moulds, not all 2k systems are compatible with semi-perm release agents and/or styrene based tooling gelcoats. Do a test, and if still in doubt, use PVA.
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ECV3
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Group: Forum Members
Posts: 30,
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Thanks for your good advise! A lot of time and effort has gone into the plug to get it 100% and i was going to use Easylease so i have mimimum fettle on the mould later along the line (my first ever mould) after your advise i'm taking the PVA route as cutting out any possible problems is paramount with only one plug and i'd rather have more fettling work than lose the plug. Should i give it a couple of coats of wax before PVA ? Its a small plug so do i put the PVA on by cloth or spray it on, and if so what size gun tip ? Cheers!
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Hanaldo
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Group: Forum Members
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I prefer to not use wax with PVA, just spray the PVA like it's a paint. The smaller the tip the better generally, PVA is quite thin (more like water than paint) so you want to spray thinner coats and allow it to dry completely before applying the next coat. It does run quite easily.
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ECV3
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Group: Forum Members
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I've been told that the tip size for PVA is 0.5-0.8mm so i'm off to buy one today. Do you spray semi-perm ?, if so can i use the same gun for both and what do i clean the gun with after PVA and Semi-Perm ?. Cheers!
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Fasta
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Group: Forum Members
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Most (all that I have ever seen) people just wipe semi permanent systems. I think it may be able to be sprayed but considering the cost of this stuff and how much would be wasted in the air? It is so easy to just wipe on?? 2k (I use polyurethanes) paints are usually ok, key is to take it slow and make sure the paint is well cured. Apply semi permanent sealer and then leave overnight. Then the final release coats. Follow the application directions on the data sheets.
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Blackrat
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Group: Forum Members
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i would wax for sure
pva provides a barrier, wax provides slip ....
if you going to be making a number of the parts the mold will season and then you will need wax only, so i would get it waxed
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ECV3
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Group: Forum Members
Posts: 30,
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Hi Fasta, After Hanaldo advised me on semi-perms and 2k i needed a smaller tip size spray gun than i have so i can spray the PVA, i had a quick google search on spraying release agents and found a few semi-perms that are spray on so i wanted to buy a gun that is compatible with both if possible so its there if i ever need to use it (and so i dont have to buy 2 if i can help it). I bought a HVLP 0.8mm smart repair gun (mini size) and after a play about with the pressure, fan, and fluid it was ideal for the PVA with very minimal overspray even on the polypropylene base board the plug was mounted on so i dont think semi-perm would go to waste in that way but dont hold me to it.
I used a cheap 2K HS ACRYLIC Clearcoat (Low Baked) on the plug and tried a text with Easylease and it did soften the clearcoat and mark it a little so i used PVA just to be safe. I will use 2K Polyurethane after your advise!. Cheers!
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Hanaldo
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Group: Forum Members
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As Fasta said, don't spray your semi-perms. They all CAN be applied by spray, but there's no need. For one, you will always get wastage. Even with a very well setup HVLP gun, you will always waste at least 25% of your material. That's just how it is. And somewhat more importantly, it just isn't needed. Semi-perms don't build a film, they evaporate. They are a polymer suspended in solvent, so when you apply them the polymer stays in the microporosity on the surface of your tool and the solvent evaporates. This makes spraying totally redundant, as the only reason to spray any material (paint, gelcoat, PVA, etc) is to get a smooth surface film. With semi-perms there is no surface film, so you can just wipe it on and it will leave no trace on your substrate. And lastly, over application is detrimental to both your tool surface and the release agents effectiveness. With semi-perms you want to apply them so thinly that they only just wet the surface before evaporating. If you were spraying, this would be quite difficult to achieve. The exception would be if you are doing something VERY large. A 50 foot boat hull for example you might question whether wiping it on would guarantee full coverage, not to mention the time it would take. Even then, I've seen a local company here prepping their moulds for a boat hull, and they just employ a team of people to cut down the work load, and apply the release agent strategically to ensure coverage.
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