Strategy for applying this surface coat

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Strategy for applying this surface coat

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quinn	q quinn posted 6 Years Ago HOT Topic Details
q Group: Forum Members Posts: 155, Visits: 992	My plug is done and I'm about ready to lay up a mold. This will be used for prepreg so I'm using premium resin tech rdr-1902 high temp surface coat and rdr-3212 resin. I have some concerns with the surface coat. It's a bit thicker than I imagined but I guess that's good so it won't run, however after mixing a small test batch, it seems pretty slow to release air bubbles. As you can see in the pic of my plug, there are areas with vertical walls and even a few areas of negative angle. For air to release from the surface coat as I brush it on, these bubbles need to rise to the surface to pop right? So any areas that are beyond vertical with a negative angle, I would think are gonna have a hard time releasing air. I picture a bubble just rising up against the surface of the plug and staying there. I'm wondering if I should apply the surface coat in partial areas with the plug oriented so surface coat I'm applying is face up, allowing better release of air bubbles. Do I need to bother? Or can I just brush it on the whole thing as it sits in the pic? Looks like pics got rotated 90 degrees, the pointed nose is up
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quinn	q quinn posted 6 Years Ago HOT Post Details
q Group: Forum Members Posts: 155, Visits: 992	Another question before I start the post cure. My mold came out great and the gloss is as good as what I got on the duratec which is pretty good, but out of curiosity I tried hand polishing a small area up in the top and it was immediately obvious that this high temp surface coat will go to a brighter gloss than the duratec did. Is there any downside to polishing my mold now? Or should I just leave it alone? It's possible there's voids under the surface but I'm sure I wouldn't expose them just by polishing. If I do go ahead and polish the mold, should I do it before or after the post cure? I imagine it will polish easier now since the hardness will go up during cure, but will i lose some gloss during the cure? Should I polish afterwards?
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Lester Populaire	L Lester Populaire posted 6 Years Ago HOT Post Details
L Group: Forum Members Posts: 311, Visits: 13K	+x quinn - 2/12/2019 7:31:38 PM Another question before I start the post cure. My mold came out great and the gloss is as good as what I got on the duratec which is pretty good, but out of curiosity I tried hand polishing a small area up in the top and it was immediately obvious that this high temp surface coat will go to a brighter gloss than the duratec did. Is there any downside to polishing my mold now? Or should I just leave it alone? It's possible there's voids under the surface but I'm sure I wouldn't expose them just by polishing. If I do go ahead and polish the mold, should I do it before or after the post cure? I imagine it will polish easier now since the hardness will go up during cure, but will i lose some gloss during the cure? Should I polish afterwards? No problem polishing. I would do it after the post cure. Hardness difference is minimal, might even be lower on some resins (some resins get tougher but the hardness drops a tiny bit). I usually do the final finishing only in the mold. You can kinda rush through the grits on the plug, as remaining scratches are going to be a ridge in the negave mould and much easier to get rid of.
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quinn	q quinn posted 6 Years Ago HOT Post Details
q Group: Forum Members Posts: 155, Visits: 992	+x Lester Populaire - 2/12/2019 9:36:05 PM +x quinn - 2/12/2019 7:31:38 PM Another question before I start the post cure. My mold came out great and the gloss is as good as what I got on the duratec which is pretty good, but out of curiosity I tried hand polishing a small area up in the top and it was immediately obvious that this high temp surface coat will go to a brighter gloss than the duratec did. Is there any downside to polishing my mold now? Or should I just leave it alone? It's possible there's voids under the surface but I'm sure I wouldn't expose them just by polishing. If I do go ahead and polish the mold, should I do it before or after the post cure? I imagine it will polish easier now since the hardness will go up during cure, but will i lose some gloss during the cure? Should I polish afterwards? No problem polishing. I would do it after the post cure. Hardness difference is minimal, might even be lower on some resins (some resins get tougher but the hardness drops a tiny bit). I usually do the final finishing only in the mold. You can kinda rush through the grits on the plug, as remaining scratches are going to be a ridge in the negave mould and much easier to get rid of. Ah, good point. Didn't consider the mold has protruding scratches. I'll probably be good enough with just a polish though. I did put a lot of time in the plug. Do you use anything special for polishing the surface coat? I have aquabuff 1000 and 2000. Just use that? Edited 6 Years Ago by quinn
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Lester Populaire	L Lester Populaire posted 6 Years Ago HOT Post Details
L Group: Forum Members Posts: 311, Visits: 13K	+x quinn - 2/12/2019 10:07:14 PM +x Lester Populaire - 2/12/2019 9:36:05 PM +x quinn - 2/12/2019 7:31:38 PM Another question before I start the post cure. My mold came out great and the gloss is as good as what I got on the duratec which is pretty good, but out of curiosity I tried hand polishing a small area up in the top and it was immediately obvious that this high temp surface coat will go to a brighter gloss than the duratec did. Is there any downside to polishing my mold now? Or should I just leave it alone? It's possible there's voids under the surface but I'm sure I wouldn't expose them just by polishing. If I do go ahead and polish the mold, should I do it before or after the post cure? I imagine it will polish easier now since the hardness will go up during cure, but will i lose some gloss during the cure? Should I polish afterwards? No problem polishing. I would do it after the post cure. Hardness difference is minimal, might even be lower on some resins (some resins get tougher but the hardness drops a tiny bit). I usually do the final finishing only in the mold. You can kinda rush through the grits on the plug, as remaining scratches are going to be a ridge in the negave mould and much easier to get rid of. Ah, good point. Didn't consider the mold has protruding scratches. I'll probably be good enough with just a polish though. I did put a lot of time in the plug. Do you use anything special for polishing the surface coat? I have aquabuff 1000 and 2000. Just use that? My composites supply has a polish for plastics that works well. But it's branded by them no idea what it is.
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