I have recently made a part and wanted to create a satin finish rather than a high gloss.
So far I have done this by spraying a 2k clear, then wet sand and finish with a scotchbrite pad.
Doing this seems ok but I am curious if anyone has any other methods/techniques to create a satin finish?
There are matting agents that you can add straight to your 2k clear that will create a matte finish when you spray it. Just be careful to measure it very carefully because the amount added determines the degree to which the finish is matted. Keep in mind that once it’s sprayed it can always be sanded and taken back up to a gloss (both good and bad, since the matte can’t really be repaired without just reshooting it)
for example:
http://www.pc.dupont.com/dpc/en/US/html/visitor/common/pdfs/b/product/dr/ChromaSystemLV/2361S.pdf
I knew of the paint additives but thought that I could get a better finish from a sanding technique rather than off the gun spraying.
I spray lots of parts but on the whole a technique done from a sanded finish is likely to be better and flatter than a sprayed finish for me.
Any other thoughts or ideas?
I do matte finish parts from time to time, very similar to what you mentioned. I typically wet sand the part with 800, or sometimes 1000 and then lightly apply a paste wax make sure not to buff. Customers have always been pleased since it’s a nice flat even surface and to top it off whenever the part get scuffed, all they need is a little wet sanding and wax to bring it back.
use a mould with a satin finish, and a low shine semi perm release agent. satin parts straight off the surface.
My parts all typically require further finishing after de-moulding for filling porosity and UV protection.
The satin moulds won’t work for me since I already have lots of moulds and a satin epoxy finish won’t have any UV resistance even if it worked.
At first I wet sanded and then scotchbrite with beeswax but it seemed very patchy with satin and gloss in places, just uneven so I went to just scotchbrite over that and it looked ok.
Pic is not so good but the part on the front of the boat hull is it.
https://www.facebook.com/Fastacraft/photos/pcb.477884912353445/477884049020198/?type=1&theater
Have u ever thought about IMC, in mould coatings?
Use a satin semi permanent release agent, then spray your IMC.
May be u could skip the final spray painting.
I would love to use an IMC but in all my testing of that with pre preg processing I have not been successful and now just finish parts after.
If you know an IMC that could work with pre pregs then let me know?
What temp does your pre-preg need? I did a test panel with Duratec Sunshield recently, but the pre-preg I used only needs 105 degrees. The Duratec has a Tg of 120,and I sprayed it on and let it cure for 24 hours, then post-cured at 60-80 degrees for 5 hours before laying up.
Worked fine for that panel.
We have a similar problem right now with a prepreg part. I know a German Distributor who claims to have an IMC suitable for prepreg applications.
I´ll keep u updated.
scott bader developed a styrene free poly gelcoat in conjuction with advanced aerospace. don’t know if it still available but apparently it worked well, but had a very strict cure cycle to ensure resin flow and bond between the two.
I may try the Duratec someday. I usually cure at 100C
PPG makes a matte clear D8113 or D8115 depending on where you are. Originally developed for Lambos, not cheap but very nice and more consistent then adding flattening agent.