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Old 08-27-2014, 01:09 PM   #21
mjalaly

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Originally Posted by dallasb84 View Post
It really depends on what you want to do. I take my molds to 2000 because its easier to polish tight spots to a shine with compound. Just easier on the fingers.

Are you brushing a good coat in the mold first before you lay fabric down? You said you were wet layup right?
Yes and yes (vacuum bag)
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Old 08-27-2014, 09:46 PM   #22
wyowindworks

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I would say that you are having a reaction of some sort with the release. The mold has clearly lost it's gloss after the first part is pulled. Did the part release difficultly? Did you fully buff the release wax to a shine? Does the mold surface gloss up with a fresh coat of release wax? Is the mold surface now permanently dulled? What kind of resin? Some resins do not play nice with some synthetic based releases like yours.
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Old 08-28-2014, 09:21 AM   #23
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Originally Posted by wyowindworks View Post
I would say that you are having a reaction of some sort with the release. The mold has clearly lost it's gloss after the first part is pulled. Did the part release difficultly? Did you fully buff the release wax to a shine? Does the mold surface gloss up with a fresh coat of release wax? Is the mold surface now permanently dulled? What kind of resin? Some resins do not play nice with some synthetic based releases like yours.
Yes it was hard to release as you can see part of the mold was damaged. I did fully buff to a shine... 4 coats and it glossed right back up. I don't think it is permanently dulled. I will need to look. I was using a system 3 on the 1st 3 layers and a cj composite epoxy on the remaining layers.

http://www.systemthree.com/store/pc/Clear-Coat-c14.htm
http://cjcompositestechnology.com/ep...-kevlar-15-gal

I have uploaded a high resolution pic that you can zoom into more clearly. Also attached is a panel I made using the cj resin, mylar tape and no mold release.

Any thoughts on how to save this part? make it glossy?
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File Type: jpg 2014-07-15 06.23.45.jpg (278.3 KB, 106 views)
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Old 08-28-2014, 08:29 PM   #24
wyowindworks

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The part can be clear-coated to make it glossy.

I would say that the dull finish was a release issue. What was the surface coat of the mold made from?
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Old 08-29-2014, 10:20 AM   #25
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The part can be clear-coated to make it glossy.

I would say that the dull finish was a release issue. What was the surface coat of the mold made from?
It is Feather Fill. I don't have a spray gun so i am not sure if i can apply a pva without issues.
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Old 08-31-2014, 03:39 AM   #26
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Pva or go with a semi perm release. Wax alone is a bad idea. I would rather brush pva and deal with the wet sanding than trust just wax.
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Old 08-31-2014, 10:26 AM   #27
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It would be nice if the pva came in a spraycan. Does the hair spray thing work?

The part you see is for the wing bottom. I still need to do the top which I want to make nice.
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Old 09-01-2014, 09:53 PM   #28
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I pick pinholes clean with an exacto knife and fill with the same resin used. Then carefully sand flush.
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Old 09-03-2014, 06:38 AM   #29
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Just my opinion, but as you know epoxy has terrible uv protection. I already knew I needed to do a 2k clear of all my parts for proper uv protection. My parts so far have looked worse than yours. After pulling I hit it with 800 grit, clean part with preferred degreaser (alchohal for me), paint with Shopline PPG 2 part clear. My parts are small so even my $180 26gallon HF air compressor does the job. I use a $20 hvlp harbor freight gun with the supplied 1.4 tip. The clear I got was like $80 maybe and will cover a ridiculous amount of parts. And it's a good skill to have. Added benefit is you can also spray Pva, which I haven't tried yet.

Last edited by Ian300D; 09-03-2014 at 06:44 AM.
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Old 09-15-2014, 09:58 AM   #30
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ok I ran the top part. this time i tried to spray on a pva but it fished eyed real bad. So i cleaned that off and just wiped it on. (pic attached)

The part popped of like nothing and the mold stayed undamaged!

I also didn't use the super slow curing resin like i did the first time. Maybe that is the reason for the added pinholes?? The pic with the two wing halfs shows the old one (background) and the new one.

Thoughts?

Can I just spray a 2k clear over it with out filling in all of the pin holes still have it come out nice??
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File Type: jpg 2014-09-14 18.03.18.jpg (912.2 KB, 123 views)
File Type: jpg 2014-09-14 18.07.15.jpg (253.8 KB, 118 views)
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