Have you tried puting a base coat on them?
You can use a primer filler to fill in they layer lines, and then use acrylic paint pens like /u/forget_the_hearse suggested.
I use acrylic spray paint, paint pens, brush paint and sharpies for all of my prints. The primer filler is amazing for filling in layer lines before puting on the actual colors.
Did you use a primer before painting? It kinda looks like you didn't.
A good filler primer can help with layer lines and other imperfections. A coat or two of this usually hides up to 0.1mm layer lines (FDM) for me. I use a single thin coat on resin prints as it can hide desired detail if you aren't careful.
Yeah I hear you. Layer lines cheapen the look for me so I find myself sanding down the majority of my prints because of them. If I can avoid a ridiculous print time I keep it as thin as possible. Unfortunately, that's usually a choice between printing a single piece for 4 hours or 14 hours. So worth it though when it works out.
When I can't be bothered but don't want it to look awful, this Rustoleum Filler Primer has been surprisingly great. Shockingly good effect.
Thanks! I printed him with PLA filament and then did a couple of coats of this filler primer
https://www.amazon.com/gp/product/B003CT4AM0/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
Did a lot of sanding with different level grit sandpaper to smooth him out and then once it was all done I started painting him with acrylic paints :)
Curious your bondo workflow. Seems like you can lose a lot of detail . Have you considered using 2-3 coats of this Primer Filler.
Capillary issue hadn't occurred to me before, but it makes sense. But if you are going to acylic matte prime it anyway, I guess trying to fill those layer gaps first is a step worth taking.
Something like a filler-primer: https://www.amazon.com/dp/B003CT4AM0/ref=nav_timeline_asin?_encoding=UTF8&psc=1
Start with Primer and do a few light coats. You don't want sagging. https://www.amazon.com/dp/B003CT4AM0/ref=cm_sw_em_r_mt_dp_Ax3bGb0T4CB22
Then use Acrylics. There are endless video guides of painting realistic terrain. Lots of nerds out there ;) https://www.amazon.com/dp/B06ZYSFWNN/ref=cm_sw_em_r_mt_dp_Gw3bGbCCBRWAC
I'd think a filler primer like this one would work but this isn't something I have much experience with. here
I use this stuff
Filler primer: https://www.amazon.com/dp/B003CT4AM0
The key is this filler primer: https://www.amazon.com/Rust-Oleum-249279-Automotive-11-Ounce-Filler/dp/B003CT4AM0
Coat, sand, coat, sand, working your way up the grit and finishing with wet-sand 800+ grit. Took a bit of elbow grease, but totally worth it for the 'hero' piece of the costume. This project was the first time I really put the effort in on the finishing and it really payed off.
I'll use 120 or 150 occasionally, it's really not an exact science. The filler primer works very well in masking any scratches you have on the print surface.
Honestly, i just sand like a piece of wood, but you don't have to get everything perfectly smooth. Like I said, the filler primer works wonders.
I use Rust-Oleum filler primer spray paint. It's usually located in the auto spray paint section at Lowes or Home Depot.
Like this https://www.amazon.com/dp/B003CT4AM0/ref=cm_sw_r_cp_apa_i_hG0cFbDFZY6FG
Also, I've found it best to print any type of detailed model with ABS. I then use vapor smoothing with acetone, you can find tutorials online. It really helps, and minimizes the amount of sanding you have to do.
Below are a few examples of PLA vs ABS. The Batman and John Snow models are PLA and you can see some of the layers still. The rest are ABS.
Some Prints of Mine https://imgur.com/gallery/V78GrSE
Just a suggestion. I really like the "Filler Primer Spray" from Rustoleum. Thick enough to hide most layer lines after a few coats. Then it ready for a couple of metallic coats.
I think I would overpaint the filler primer on this and repaint.
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Very nice work!!!
https://smile.amazon.com/gp/product/B003CT4AM0/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1 This is the one I used, hopefully its not too much more expensive but it was $4.70 for me.
I have used this on restores. Since you are working on new stock, two coats would work. Use an orbital sander 120, 220, and then 320 grit discs.