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Discussion Starter · #1 ·
Hi All-
I am starting assembly of a 3-D digitally printed critter and not sure of what the material that is used in this process. The vendor instructions simply said to prime and then paint but no suggestion as to what kind of primer and paint to use. So I'm asking for suggestions: what type of primer (brand name would be helpful) as well as type of paint. I assume spray painting is preferred method of painting but I don't have a sprayer so maybe pressurized paint cans?
Thanks-
Robin Young / Forest Hill, MD
 

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On some projects I sand the heck out of them. 80-120-500. Pla will get as smooth as injection molding, just don't want through the shell!. On small projects that sanding is near impossible, I paint with a mixture of 50-50 acrylic putty (painters) and water. This covers the grooves and gives a nice flat, but not too flat finish. Looks more like steel or iron when painted. I use Krylon primer and paint. Rattle can because I hate cleaning anything but water based out of my airbrush. Hope this helps!
 

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Discussion Starter · #3 ·
Thanks Exador, there will be a bit of sanding and smoothing required so your grit recommendations are noted. Not sure what "Pla" refers to (maybe plastic?). Also I don't know what acrylic putty is; is it available in a hardware store. I like Krylon paint so that will probably be my choice of method.
 

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Hi Robin,
Do you know if you can find out from the vendor how and what it is printed with?
Filament printing will of course leave you with the layer lines.
If PLA, then I would recommend using Rust-Oleum FILLER PRIMER spray can.
It's a nice thick primer that will fill the grooves and sand nice and smooth.
If PETG, then you will find that paint does not stick very well and so I use 3D GLOOP to smooth and prepare so that paint will sick.
I still use the filler primer, but any primer should work after the Gloop.
There is also a 3D GLOOP for PLA which I have not used that will smooth out the striations too.
If it is a 'resin' print, then you will not have striations, but I have no experience with painting, but probably any primer should work.
Let us know how you get on.
All the best,
David Leech, Delta, Canada
 

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Robin,
I just thought, did you buy this from Shapeways, or similar producer.
If so, it might be a completely different process altogether.
You really need to find out what material it is made of, to help decide the best adhesive and paint to use.
Cheers,
David
 

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Discussion Starter · #6 ·
Hi David-
I bought this kit on an ETSY site (not very familiar with how ETSY works so I'm having a hard time communicating with the vendor). I think I've got the vendors mobile number so just sent a text asking him to describe the material used. Once I find out (fingers crossed) I'll post that and follow suggestions based on that info.
Thanks-
Robin
 

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Hi Robin, good luck with the critter. :)
maybe pressurized paint cans
Definitely. There's another thread today about repainting boxcars that might give you some thoughts on technique.

I often use the Rustoleum 'paint-and-primer' spray cans, especially if I am going for a dull or semi-gloss finish. But you do need to figure out whether it is resin or PLA or PETG or what? I often paint resin figures using a plain flat grey primer then acrylic brush paints for the details.

As you probably found, 3D printed items can have layers showing, which is why David and others suggest sanding.
 

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Discussion Starter · #8 ·
Hi Pete-

The vendor quickly responded with good info (I hope). The material is "ABS-like" (don't know what that means) which he says is a "mix". Not being familiar with this 3-D printing technique I don't know the various materials commonly used for the hobby. And TLA's always throw me for a loop (i.e. PLA or PETG). Ah, what's a TLA you ask.....Three Letter Acronym!

He uses Rust-Oleum automotive primer after which any paint should work fine. Sometimes he uses "model" paint and other Krylon or Rust-Oleum. He most often uses spray cans but uses airbrush (I don't have one) for weathering but also brushes paint onto some parts. Since I don't have any spare material to experiment with I hope to get it right the first time.

By the way, the surface finish looks very pristine in my opinion, so sanding might not be necessary except to rough up the surface just a bit. And, there is no evidence of various layers so having to fill layers in probably won't be necessary either.
 

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Would be interested in seeing what the kit is. Can you post a link to it?

Months ago, I found a site with a printable small locomotive and some cars. A guy I know had one printed for me at some "maker" club place and never got a chance to fool with it.

I have seen "plastic adhesion promoter" spray cans for sale, but not often. The one i tried left a clear matte finish and smelled like spray matte clear.

Doug
 

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PLA stands for "poly lactate acid" a kind of plastic. ABS is another kind of plastic (Legos are ABS). PET is yet another plastic. All of these are "filaments" used in the most common 3D printers, rather than resin bath printers. I use rattle cans to prime my plastics, mainly because PLA does not play well with sunlight. I sometimes just use grey paint. Lately I've been using "craft paints" which are water soluble, have no nasty smell, and clean up easily.
 

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I recently painted three tipper cars from the same Etsy seller. I used my usual method of Rust Oleum primer (some rusty metal, some self etching because I had them) and top coated with Rust Oleum enamel then overcoated with Rust Oleum matte finish to dull them down. I then used craft paints for weathering. So far it all looks good. I showed the items to friends who are more 3D printer savvy than I am and they were impressed. I will be purchasing more items from this seller.
 

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Discussion Starter · #16 ·
Tom-
This is my first product from this vendor on ETSY and, other than the flat parts (i.e. side, front, rear) being slightly warped, I'm impressed with the detail. A couple minutes in the toaster oven at 200F and they seemed to flatten out fine.
My big challenge now is to figure out what R/C controls I will need (forward/stop/reverse and speed) and I have absolutely no experience with these at all. I've been watching this forum for little nuggets of info. and hope I can buy the needed components that will all fit under the bonnet plus the 4 batteries.

Speaking of batteries, I bought (4) EBL Li-ion 3.7V batteries with charging cable which I think are really slick. Stick one end of cable into USB port/power supply and the other into the actual battery. Don't know how many batteries I'll need to run this critter but stuffing batteries plus controls under the bonnet might be a real trick.
 

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I only have 2 locos currently so I use a flysky transmitter and 3 channel receivers. It's was around $40 on ebay. I've been using the 12 + 18v batteries from Harbor Freight. I have a small outdoor layout so it's feasable. Of course if you have 10 locos, not so much.
 

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