Removing Layering from 3D Printed Bodies.

[Kayma367]

I'm in need of some guidance from those more in the know. I'm jumping back into the hobby after a 24-year lapse and decided to start with a 3D printed kit of about 40 pieces. I thought it would be an easy project to ease myself back in, but my perfectionist side has me puzzled. On some of the curved upper surfaces, namely the leading edges of both the hood and roof where it meets the top of the windshield, I have striations that are noticeable through the primer (see photo).  My questions: 1.) is this something that can be sanded out without ghosting back; 2.) is this something that can be fixed with a filler primer and more sanding; 3.) is this something that can be fixed using a little bit if putty/glaze and more sanding? Apologies if this has been asked and answered before, I did a search but couldn't find anything this specific. I'm using Tamiya paints exclusively and don't want to ruin what I've already prepped by using another product that might not react well with either the paint or the 3D resin. I'm not looking for a glass-like surface, but a smoother surface to paint would be a nice start. Please let me know your thoughts and thank you in advance! John

Edited March 31 by Kayma367

[stitchdup]

if its a resin kit start your rounds of primer with a good high build primer. mask of any of the finer detail, then give it a coat or 2. block it back starting at 400 w'n'd, prime again and work up the grades of w n d until you get to around 800 or 1000 then its just repeat until your happy. you can do the lower grits a few times before building up and i like the tamiya sponges for first prep on the bodies. sometimes just the sponges are enough to prep the lower striations but i'll still use this method each time too.

if its one of terrible nylon prints from shapeways you have lots and lots of work to do and the best advice i can give on those bodies is chuck them away and find a resin print. the nylon does not cut, sand, file or play nice in any way

 

edit- I've used duplicolor auto acrylics with tamiya without problems. just give it an extra day or 2 between paint types.

Edited March 30 by stitchdup

[hedotwo]

I agree with Les about the high build primer.  I've used Mr Surfacer 500 primer on a few of the 3D prints and while it doesn't eliminate sanding, it definitely helps fill the light lines.

[peteski]

John, I hope Texas_3D_Customs doesn't see you using the term "striations" for describing those 3D printing artifacts.  I did that  once and he reamed me a new you-know-what for that.  I still have that exchange of PMs between us.

[Shark]

For getting back into the building game, you didn't dip your toe in the water, you went ahead and dove in the deep end with that project.      Welcome back

[64SS350]

As in another thread, I mentioned I like using thin CA first. Then start sanding, and continue with primers as needed.

[OldNYJim]

4 hours ago, peteski said:

John, I hope Texas_3D_Customs doesn't see you using the term "striations" for describing those 3D printing artifacts.  I did that  once and he reamed me a new you-know-what for that.  I still have that exchange of PMs between us.

What term does he suggest we use?

[89AKurt]

Following this OT!   My last build, I had many accuracy corrections, but did more sanding than usual before paint.

[peteski]

1 hour ago, OldNYJim said:

What term does he suggest we use?

Well, here's a quote from one of his angry PMs to me:
All I did was show you a picture of my bodies you go off using that stratation word Man nobody uses that word and it is referring to geological features you want to try to turn into something 3D printing to sound fancier whatever you want to do go ahead voxels That's actually a very common 3D printing term I'm sorry that you're out of your league and you don't understand the common terminology for 3D printing but you want to act like you're an expert in it go ahead prove me wrong

But whatever he says, striations is a perfectly good word to use for this printing artifact because the printer builds the object in layers and those look like striations. I don't care what he says.  Voxels are the single print elements, not the entire striated layers. This has nothing to do with being right or wrong - If I want to call it striations I should be able to do do so without anybody having a conniption.

[Texas_3D_Customs]

2 hours ago, OldNYJim said:

What term does he suggest we use?

Layer lines but it really has to do with the settings of the person doing the printing. Most modern printers have very small voxels "pixels kinda" and with the correct orientation and anti alias settings they are not that noticeable with the naked eye, but to mitigate them a good filler primer with some post processing will make a big difference. But there also appears to be a layer shift on that part as well. How much magnifying did you do to show those lines? If you zoom in on my parts they are there but once painted they are imperceivable. But it really comes down to experience to make a print with no noticeable layer lines.

[Texas_3D_Customs]

7 hours ago, peteski said:

John, I hope Texas_3D_Customs doesn't see you using the term "striations" for describing those 3D printing artifacts.  I did that  once and he reamed me a new you-know-what for that.  I still have that exchange of PMs between us.

Still holding on to that I see 😜

[Bugatti Fan]

Striations, layer lines, voxels whatever ?    I can see where this conversation might be going.

Not everyone is au fait with 3D printer usage terminology. The OP and Pete used the term striations probably like many others including myself not knowing what else to call them. I can understand a manufacturer defending their corner so to speak with regard to product quality. No matter how passionate, but picking up on someone else's use of that term and saying that they were 'out of their league' for not understanding regular users 3D printing terminology could have been worded a bit better I feel.

I recently bought a 3D printed car body to make a model of a car I used to own. The layering looked like the contours shown on a map that needed lots of rubbing down and filling. There can be big differences between various manufacturers products. They can differ from high quality to indifferent to downright poor. My particular example did not impress. What is offered is so dependant on both  CAD programming ability and 3D printer quality. Some manufacturers are extremely good at what they do and make high quality products Then there are the dabblers who think they are better than they are and start putting out stuff prematurely and will quickly fall by the wayside.

We have seen parallels in white metal kits and resins made from masters. The better ones survived and the poor quickly disappeared into oblivion.

Getting back to the OP. After a lapse of a number of years perhaps getting back into it with a regular injected plastic kit might have been easier than committing to a 3D printed kit straight away. John and Les have both come up with good suggestions. Apart from their suggestions I found full size automotive primer used on my model worked quite well for me.

Edited March 31 by Bugatti Fan

[bobss396]

I have a printed stock car body and on the sides, it looked almost like shiplap siding.

Fortunately there is no fine detail to be concerned with. So I start wet sanding with a #400 sanding stick, which was getting nowhere.

I dropped down to #180 and made progress from there. I finished up with  #800 sanding pad. 

I have another stock car body that has finer detail to consider. Some of these wear like iron, so I'm doing it area by area and trying to not make MORE work for myself.

[peteski]

7 hours ago, Texas_3D_Customs said:

Still holding on to that I see 😜

Absolutely!  That butt-reaming I received from you was save-worthy. Remember, what you post on the Interwebs stays out there for as long as the Internet is around.  As you can see here, I'm not the only person who is not directly involved in 3D printing who sees those layers as striations (that term is not exclusive to geology).

[Texas_3D_Customs]

4 hours ago, Bugatti Fan said:

Striations, layer lines, voxels whatever ?    I can see where this conversation might be going.

Not everyone is au fait with 3D printer usage terminology. The OP and Pete used the term striations probably like many others including myself not knowing what else to call them. I can understand a manufacturer defending their corner so to speak with regard to product quality. No matter how passionate, but picking up on someone else's use of that term and saying that they were 'out of their league' for not understanding regular users 3D printing terminology could have been worded a bit better I feel.

I recently bought a 3D printed car body to make a model of a car I used to own. The layering looked like the contours shown on a map that needed lots of rubbing down and filling. There can be big differences between various manufacturers products. They can differ from high quality to indifferent to downright poor. My particular example did not impress. What is offered is so dependant on both  CAD programming ability and 3D printer quality. Some manufacturers are extremely good at what they do and make high quality products Then there are the dabblers who think they are better than they are and start putting out stuff prematurely and will quickly fall by the wayside.

We have seen parallels in white metal kits and resins made from masters. The better ones survived and the poor quickly disappeared into oblivion.

Getting back to the OP. After a lapse of a number of years perhaps getting back into it with a regular injected plastic kit might have been easier than committing to a 3D printed kit straight away. John and Les have both come up with good suggestions. Apart from their suggestions I found full size automotive primer used on my model worked quite well for me.

You have to understand it's not so much using that word He's taking things way out of context and he's not really telling a full story and use whatever word you want.

[Mustang fan]

I have been experimenting a lot with resin 3D printing lately, and like many others I have noticed these layer lines appearing on some rather "horizontal" surfaces. These are more or less pronounced, depending mainly on the layer thickness, a parameter you can adjust in the printing parameters of the slicing software.

Basically, the finer the layer setting, the less visible the lines will be. I currently use 20um as my default setting, and while not completely invisible, the layer lines are faint enough that a good coat of primer will make them completely smoothed out (I use Mr Surfacer 1000 for that).

For info, my printer is an Elegoo Mars 4 , with a x-y resolution of 18um. I do not use the anti-aliasing feature as I found it does not seem to be effective.

As for the commercial resin prints, it seems they are mainly printed using 50um layers, probably to save printing time (printing at 20um layer height takes 2.5 times more than using 50um...)

 

 

[OldNYJim]

Reminds me of this, from the news recently:

https://nypost.com/2025/03/02/us-news/new-york-strip-steak-would-be-renamed-after-texas-in-move-that-could-spark-interstate-beef/

[Mike 1017]

This a picture of striations.

[stitchdup]

9 minutes ago, Mike 1017 said:

This a picture of striations.

or an extreme close up of my thumb when i get out of a hot bath

[Mike 1017]

1 minute ago, stitchdup said:

or an extreme close up of my thumb when i get out of a hot bath

Same thing on BIG Mike

[Kayma367]

Thank you all for your responses and the education on using the correct verbiage (title line has been updated for posterity sake). I'll milk being out of the loop for 20-something years until I can find another excuse. Looks like Mr. Surfacer is the way to go and I promise my next project will be a plastic kit that will go together without the extra hassle. John

[iamsuperdan]

Just make sure it has no striations. 🤪

 

 

 

 

[peteski]

7 hours ago, Texas_3D_Customs said:

You have to understand it's not so much using that word He's taking things way out of context and he's not really telling a full story and use whatever word you want.

LOL Charles, it is you who doesn't get it.  To me the word "striation" describing the visible stepping of printed layers on 3D printed objects is perfectly in-context.  Whether you think is right or wrong makes no difference to me, and everybody you ask will know exactly what I mean when I use the word "striation" in relation to surface of 3D printed objects.  STRIATIONS, STRIATIONS, STRIATIONS!

John came to the forum asking for some technique to eliminate those pesky striations on 3D-printed surfaces due to the way 3D printing builds the object in layers (which gives it a look of a topographical map).  I'm not sure about this "not telling the whole story".  What's the story and who is not telling it all?
 

[stitchdup]

this seems like a you two conversation, if you want to carry it on go to pm please. theres enough drama outside

7 minutes ago, peteski said:

LOL Charles, it is you who doesn't get it.  To me the word "striation" describing the visible stepping of printed layers on 3D printed objects is perfectly in-context.  Whether you think is right or wrong makes no difference to me, and everybody you ask will know exactly what I mean when I use the word "striation" in relation to surface of 3D printed objects.  STRIATIONS, STRIATIONS, STRIATIONS!

John came to the forum asking for some technique to eliminate those pesky striations on 3D-printed surfaces due to the way 3D printing builds the object in layers (which gives it a look of a topographical map).  I'm not sure about this "not telling the whole story".  What's the story and who is not telling it all?
 

 

[Oldriginal86]

My wife tells me, “ it’s not what you say, it’s how you say it”.