How do do i smooth out my 3d printed parts?

[Michael McCourt]

I have been 3d printing parts in PLA, as you can see from the picture they are not smooth. is there some kind of primer or putty i should use to help smooth it out? sanding it by hand is not easy and ridges seem to not go away. any advice would be great.

[Sinksalot]

Make sure you 3D printer is tuned to print great. The better tuned 3D printer, means less sanding. Also some filaments sand easier.

[Subculture]

I use this stuff mainly.

[tifosi12]

I have tried primers and putty and nothing really worked. IMHO the best approach is to select the best resolution of what your printer can do. In addition I discovered that some printers are better at this than others, regardless of what their technical spec sheets say. And finally think about the way the layers are created: All vertically, so if your object is a flat object, don't put it flat on the print bed, but vertically where the layers blend.

Also experimenting with different PLAs might help. I tried "wood" PLA as somebody said it sands easily. That's kinda true but the drawback is that it also easily cloggs up your printer's nozzle. So no more "wood" PLA for me.

And finally (while putting on my fireproof suit): Why bother? The sub is at least 6 feet away from you in the water, likely 1 feet below surface, nobody is going to see any printing artifacts. I never quite understood folks who are trying to make their RC subs looks as good as static display submarine models. RC flyers don't do that. They know you have to cut some corners for functionality, so why hold a RC sub to a higher standard? Just my $ 0.02.

[598602G]

I had one of those 3D printed boats and wouldn't give dog spit for another one. Sand, sand and more sanding. 220 grit will get close but you will still have a fuzz. I mixed up some West System epoxy and thinned it down with 91 percent alcohol and brushed on a thin coat on the hull to fill in. Stick with old tried and true epoxy glass hulls like the kits I use to make and sell. Stay tuned as I am fixin to make some more sub molds and sell some kits. Epoxy fiberglass kits I might ad.

[Sinksalot]

I tried PLA, and PLA+. it printed good but sanding it was a pain. Then I switched to ASA filament, sanding ASA easy. However ASA filament is tricking to print and requires a printer that can do 250 to 270C. Also requires the 3d printer be enclosed.

[SubDude]

I have printed PLA, PLA+, ASA, ABS, ABS+ and PETG. Much depends on the settings in your slicer. I use Simplify 3D with an Ender 3 Pro and Ender 5+. Currently I am printing a 1/48 Thresher in ABS+. PLA is more difficult to sand and drill than ASA or ABS but as mentioned they can be trickier to print and can give off some fumes. My printers are in my basement so fumes are not a problem for me. PLA also requires more care keeping it out of the sun than ABA or ASA. None-the-less, while I get great results from ASA and ABS and will never go back to PLA. I use an automotive grade high fill Polyurethane primer called Finish 1. It is expensive but well worth the money in my opinion as it dries fast, is catalyst cured instead of air dry, is so easy to sand and will in most cases fill any layer lines in one application. I also use Rage Evercoat filler for any large deep gaps or low areas and Nitro Stan glazing putty for small stuff. The primer I apply with a cheap HVLP spray gun. After priming I will often wet sand it with 320 and it is ready for paint. Everyone has a different process, this is just mine. Everything has pros and cons. I don't promote 3D printed hulls over GRP or vise versa. To me it really depends on the boat. I think some are better suited for 3D and some for GRP. I get such good results with my 3D printed boats that it is sometimes difficult to tell they aren't GRP hulls.

[Reckless]

always depends what said parts intended purpose is ... I'm not opposed to epoxy coating ... but generally just sand and high fill primer, depends what kind of external details it has too.

I used high temp PLA .. however I have been thinking about switching to PETG .. possibly ASA .. I recently purchased an ender 5+ (after building/breaking/upgrading a Prusa clone for several years) and have been needing to do the enclosure bit to it.

Unfortunately all of my modeling ..etc has been put on hold as we've been forced to move (packing and purging 13 years of living somewhere WEEEEE )

For the record ... I've had parts made with the Proto Pasta HTPLA inside my cars engine bay for months and shows no signs of degradation or deformation yet... This PLA alloy however seems to be WAY more expensive now adays then possibly better forms on the market that have arrived under my nose :D

[tifosi12]

I got into 3D Printing when it was in it's (What is this machine for) 20 years ago!





You wanted to get into 3D Printing, you had to build your own machine! When completed, a simple small one piece build took hours to complete!

This is what got me into 3D printing, the machines, construction, and the lay-up of each layer of PLA one on top of the other to form the object you where trying to build. I personally like to see those lines in my project! It shows the complexity of the build (which to me is an art form in itself) So for me it's print out the sub, slap on a little paint, and hit the water! (I have nine (9) 3D printed subs to date, and more coming!


OK! I have said enough! Just get out there and enjoy the art of 3D printing for what it is!!

Rob
"Firemen can stand the heat"

I like your attitude.

To me 3D printing or not is not a "religious" question but rather of necessity: I am very selective in what sub I want to build. If it exists in plastic already, great. If not, I'll look for a 3d model and if I find one, 3D printing it is.

Also as a 3D model I can change it in scale and also tweak it towards RC conversion, something that's much harder to do with an existing plastic model

[Reckless]

I like your attitude.

To me 3D printing or not is not a "religious" question but rather of necessity: I am very selective in what sub I want to build. If it exists in plastic already, great. If not, I'll look for a 3d model and if I find one, 3D printing it is.

Also as a 3D model I can change it in scale and also tweak it towards RC conversion, something that's much harder to do with an existing plastic model

This... at the very least .. WHEN I cock up one of my 3d printed sections I can print another and repair... and not cry over making the wrong cut (or worse) a $500 hull ... and I can also import atleast the STL file into a 3d program (on days I want my computer to hate me ) and can design specific parts to said design.... or attempt to make changes (ofcourse making an STL solid again is another making my computer absolutely hate me and want to combust)

but working from an existing hull/model on the market that probably already has pieces made an available has very much its own advantages.

I can't scratch build at the frequency I used too (or want too) due to work injuries ... 3d printing and CAD allow me to get back into that mind sense and feeling

I really need to get this house moving thing and resettling over with so I can go back to doing just that LOL

[tifosi12]

This... at the very least .. WHEN I cock up one of my 3d printed sections I can print another and repair... and not cry over making the wrong cut (or worse) a $500 hull ... and I can also import atleast the STL file into a 3d program (on days I want my computer to hate me ) and can design specific parts to said design.... or attempt to make changes (ofcourse making an STL solid again is another making my computer absolutely hate me and want to combust)

Yes, couldn't agree more.

So far I haven't seen a single RC sub "kit" that would work out of the box as advertised. Same goes for all the 3D sub files you can buy. But at least with the STL files I can modify them to the point that I can work with them. I'm not a great craftsman so modding a plastic or even fibre glass hull to me is a LOT more difficult than changing files on the PC and print them out again.

[Michael McCourt]

Thank you everyone! very helpful ill try these ideas out!

[CC Clarke]

This may fill in a few blanks. The XTC-3D coating works well when applied properly and is easier to sand than PLA.

PLA Smoothing: How to Smooth 3D Prints | All3DP

CCC

[trout]

What I will be saying here is complete hearsay, I have not tried this. I saw a post where a person painted on resin for 3D printer. Cured it (put it in the sun) and sand.

[Subculture]

So far I haven't seen a single RC sub "kit" that would work out of the box as advertised.

I can think of several.