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help with polishing ( swirl marks )
help with polishing ( swirl marks )
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help with polishing ( swirl marks )
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jingato
j
jingato
posted 5 Years Ago
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j
Group: Forum Members
Posts: 9,
Visits: 48
Hi. I am working on the final stage of my first carbon fiber skinning project. I used all XRC products and carbon from easy composites and the process went smoothly. I did do some of the early sanding with a random orbital sander at 240 grit. I then wet sanded by hand using circular motions from 400 up to 3000. At that stage, the product looked really good, but had a dull, matte finish. I don't recall having any noticeable swirl marks at that time, but it is possible they just weren't visible.
Anyways, today I did the polishing. I did all polishing using pads that I also bought on easy composite and attached to my random orbital sander. I started with the
NW1 super cutting compound ( black )
, then used the
TopFinish 2 ( black )
, and then finished it off with the
EasyGloss
.
Below is the final result. As you can see, there are a lot of swirl marks. I'm not really sure how to proceed now. Should I just try a second round of polishing? Should I go all the way back to the sanding stage? Should I give it another coat of resin? Or should I spray it with some automotive clear coat? I have the clear coat and wouldn't mind doing that, but would that fill in the swirl marks? I don't want to spray it and then regret it.
What do you guys with experience recommend?
Thanks!
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polish
polishing
sanding
swirls
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help with polishing ( swirl marks )
jingato
-
5 Years Ago
These are sanding marks not swirls. You were moving to fast trough the grids. You defenetly can sand it with 800 and clearcoat it:)
beliblisk
-
5 Years Ago
Ok, thanks. That is good to know. I will go back to the sanding at 800. I don't mind working it back up to 3000 either. Would you recommend not sanding in circular motions? Also, is there a benefit t...
jingato
-
5 Years Ago
I would say that it depends on your cosmetic standard for finished product. Its really hard to make glass like finish with sanding (i mean really no scratch what so ever). Scratches will only appear....
beliblisk
-
5 Years Ago
That looks really good! I'll try the same :) Thanks again
jingato
-
5 Years Ago
I would just sand it with 800 and clear coat it as perhaps you dont have much epoxy there to play with anyway. If you see sinkholes when spraying dont try to fill them in a single go.... it usually.....
beliblisk
-
5 Years Ago
Hey, so I went with the clear coat using a spray can and I got the orange peel like you mentioned. I did some sanding, but then it looked like it was spotty. Perhaps I sanded too much after the clear...
jingato
-
5 Years Ago
The NW1 will work on resin from 1200 grit upwards, but generally 1500 grit or finer makes it much easier to work. NW1 is a diminishing abrasive so the more you work it the finer it gets so you need t...
Warren (Staff)
-
5 Years Ago
Just in addition to beliblisk and Warren's advice - 240 grit is WAY to harsh to have much hope of polishing out to a true full gloss. If you need to start with anything harsher than 800 grit in order...
Hanaldo
-
5 Years Ago
Gelcoat isn't for skinning, it is for making parts from a mould. The blemishes on that small piece look like areas that still have clear coat. Whether they are two spots where the clear coat hasn't....
Hanaldo
-
5 Years Ago
ah, ok, thank. Gonna keep experimenting with the smaller piece then. I have some new clear coat that I am going to try too. I think I'l sand this one again, clear it, then sand with 2k and polish and...
jingato
-
5 Years Ago
Hanaldo, do you use an air fed mask for 2K spraying? I'm led to believe that its dangerous stuff and am currently mulling over whether I will try some 2K spraying myself or just leave it to the...
bennyT
-
5 Years Ago
I do not, I just use a top quality Sundstrom respirator. Mainly because I only have a 2-stage filter on my setup not a 3-stage, so my compressed air isn't breathing quality. That is critical for...
Hanaldo
-
5 Years Ago
Here in Europe 2K hardeners with Isocyanate production or import is banned since 2017 and now mostly phased out and unavailable. Try looking for Non-Isocyanate hardeners with acrylic car paint. I...
torstenker
-
5 Years Ago
Just wanted to give a quick update and also let you guys know about a product I found and used. So I tried the regular spray can clear coat and the orange peel was horrible. I sanded it and got most....
jingato
-
5 Years Ago
When removing orange peal most of the time you dont need to get it 100% flat (unless you are looking for glass like perfection). Its a pain in the ass to get all sanding marks out anyway so for...
beliblisk
-
5 Years Ago
Bang on, agree with all of this - especially the last sentence :laugh: I agree with not completely removing the orange peel, as orange peel will actually hide print-through to a degree and can...
Hanaldo
-
5 Years Ago
Holy crap, that looks ridiculous. I literally was looking at it for at least a minute trying to understand why you posted an image of a shed door. I didn't even realize that the cf part was there...
jingato
-
5 Years Ago
Print-through is an effect you get in composites as a result of the shrinkage of the resin. All resins shrink as they cure, and for the most part that occurs in the mould while the surface is...
Hanaldo
-
5 Years Ago
Also worth waiting until the part has been post cured before doing any finishing work as the post curing process itself can cause a bit more print due to shrink back. Post curing in the mould will...
Warren (Staff)
-
5 Years Ago
That EVO 9 roof from that "shed door" picture was far from perfect i just got it leveled befor it got a lick of paint:) Post cure will speed up epoxy shrinkage (idea is to get it as close to fina...
beliblisk
-
5 Years Ago
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