I've recently been experimenting with Acrylic modeling paste. This stuff is THICK! However, it can be thinned with water. You can apply it with a brush easily. The real party trick is once its dry, to get some water and a low grit sanding sponge. The water will "re-activate" the paste a little allowing you to sand/move the putty around to smooth it further. Works pretty well and is less "chemically" to other options. Also, it sands REALLY well.
for note, i use to do bodywork all day everyday, mostly fiberglass i HIGHLY recommend 3m goggle gear 500 safety goggles. Not only are they inexpensive, so everyone can get them, but the lens is also replaceable if you want to have back ups incase you break or scratch them, the gg 500 is D4 rated and should be more than enough here, but if you want to be extra sure go for the gg 2890 safety goggles that are D5 rated (fine dust), which are also over the glasses goggles for all you glasses needing folk for the face masks/resperators my single use go to is the 3m specialty particulate respirators 8000, its an N95, P100, P95, R95 rated mask and worked quite well in my very dusty environment, and it had an breath exhalation valve so it didn't get too hot. for reusable resperators i very quickly fell in love with the half face rr 6300, as it could be set up for vapors and fumes like when i was painting cars, or dust of all types, it had replaceable cartridges so you just gotta pick the one that suits best for you
My godness, Angus... I used to watch you like 10 years ago and actually learned English by watching your stuff! It's been so long and it's just great to see you're still putting out great 3D printing content. Cheers & stay awesome
There is a setting I've found really helps eliminate layer lines while printing. In Cura, under Walls, the Outer Wall Inset distance is the key. I set mine to 0.2mm and print at 0.12mm layer height and the results are very much like a resin print. You get better surface detail too.
@@micahbogue6031 Technically, it doesn't make the outer wall thinner, it moves it inward by the amount of the setting, overlapping the inside wall. So in effect the outer wall is thinner, and there is more squish against the 2nd outermost wall. You can really see the difference when printing a mini for D&D.
I recently printed something in a color I absolutely loved, so priming and painting weren't options. I knocked off the major surface blemishes with 100grit, evened out the surface with 250, then smoothed it out incrementally using 500 - 3000. It left a really cool, brushed finish Werth the layer lines looking like the grain of the material. To smooth it all out and make it all shiny, I used neutral shoe polish and basically spit shining the entire thing before sealing it a few coats of liquid floor polish. It's totally smooth, lost no detail, I can see my reflection in it, it smells surprisingly good, it's totally water proof and I didn't lose the color of the filament. I would definitely use this technique again, as the end result was definitely worth the time investment.
@@TheSixthRagnarok the brand doesn't matter (is basically just clear wax) and neither do the number of coats. As anyone whose ever polished their shoes to a high shine knows, you apply thin layers and go until it's as shiny as you want/need it to be.
I've made wind and brass instrument parts from black PLA: they really come out looking like ebony wood, which is a huge bonus. They also feel luxurious, smooth and silky, there is a nice warmth in the material when you touch it. I use water at each stage, including the rougher grits to keep temperature down. Add a bit of dish soap in the "coolant" and you can use some power tools, carefully of course. As long as there is plenty of that "coolant" in there, you can go surprisingly fast but as anyone knows who has tried it: the risk of ruining the surface for good is great. I use car wax as finisher, after two polishing compounds..
if you need a high gloss finish on a part, i STRONGLY recommend getting yourself the hobbyist set of MicroMesh pads. these things can take a print from looking like well... a painted piece of plastic, to looking like it's dyed glass. Best part is, unlike sand paper which can actually be quite aggressive in how much material it removes, MicroMesh is very gentle on the parts, so you can retain sharp edges.
For anyone who wants to avoid the "orange peel" look after painting, you will need to wet-sand the paint. If you want to take it a step further and make the part look amazing, you can add clear coat, but you will - you guessed it - need to wet-sand to avoid orange peel. This definitely works best for larger surfaces, though. Since spraying paint and clear coat will fill in most fine details.
To add to this, 2k (1k works too) automotive clear coat will be exponentially better at protecting things than clear coat you get at a hobby store. Especially if you're coating things that get handled often. I made a 3d printed hitbox-style controller, and it would look disgusting right now if I hadn't used 2k clear coat. Any brand should be fine.
For the parts I make, my preference is to use "fuzzy skin" on prusaslicer, then sand the part a little bit. It almost completely takes away the layer lines and makes it have a nice texture that feels like a sand-blasted injection molded part.
@@roofoofighter It does, because the little spikes go outward horizontally, so they end up masking the layer lines. And once you sand it just a little bit, nothing intense, it has this like nice textured smooth feel. You can also set it to be fuzzier in certain layers than others, so you can really play around with it. Ultimately, I would much rather get the machine to do as much work as possible on the front end so I don't have to get tennis elbow sanding plastic.
Another tip if you want to sand a print but don’t want to paint it and want to keep the original look of the filament you can rub Vaseline into the print where you have sanded and it will remove the white sanding marks back to original colour.
Wood filler is great for filling layer lines, it’s water based so it’s easy to clean up, dries fast, relatively cheap, and easy to sand to a smooth finish.
This is what I use, it's great stuff. I printed the Blade of Chaos in full scale and used wood filler to hide the gaps between the parts. Came out a treat.
Polymaker sells an 'easy sand' PLA they call CosPLA which I decided to try recently and have fallen in love with - it prints like regular PLA but the plastic is slightly softer so it takes sanding much more readily - I've been doing 150 -> 220 -> 400 with no fillers at all and getting totally smooth parts fairly quickly, on par with working with pine or similar. For people in the US (and I think Canada?), for a spray filler/primer, my go-to has been the Duplicolor filler/primer sold at most chain auto parts stores. It's kind of pricey (~$18 USD a can) but both the build and the adhesion are far superior to any of the other filler/primer sprays I've tried.
So you asked for a talcum replacement. I'm not 100% sure, but you could always try a small batch with 'maizena', this is basically cornstarch. It's normally used to thicken food items but I don't know why it wouldn't work on resin.
If you have access to a sand blasting cabinet, blasting with soda is a phenomenal replacement to sanding. I use it particularly with resins, but it works great with PLA and PETG without the friction melting anything and gets into the nooks and crannies better than sanding ever can. Typically I just blast the model evenly for a few minutes then soak and rinse in water. Depending on the aesthetic I'm going for, I'll either hit it with clear coat for a gloss finish or I'll leave it as it and rub a tiny bit of WD-40 on it so the model keeps the texture but the WD-40 clears up the remaining whiting effect from blasting.
I make a LOT of cosplay weapons with extreme attention to screen accuracy. Here's my process: 1) use a high quality printer like my PRUSA i3 Mark 3 and XL and print at .15mm layer height. My prints usually come out ready for primer with no sanding required! It pays for itself in the amount of time you save in NOT having to prep a model, 2) use Bondo spot glazing putty to fill in obvious layer lines or supports areas gaps ... pro tip - this stuff is acetone based so you can squeeze some in a cup and add a little bit of acetone and now you can paint on the glazing putty which enables you to cover large areas quickly! 3) sand glazing putty areas with 220 sand paper , 4) 2-3 coats of Rustoleum 2 in 1 filler sandable primer, 5) wet sand with 320 (most layer lines should be gone with this step but repeat if necessary), 6) 2nd round of the same primer,, 7) wet sand with 600. Repeat steps 4-7 until part is perfectly smooth and it looks like a mirror. You are now ready to paint. Note if you are doing large pieces like say Mandalorian armor you'll want to use 'guide coats' along with the primer to ensure the part is finished perfectly smooth with no high or low spots. Using this process people are always amazed that my props are plastic and not metal. Of course you need to have some skill with an airbrush or rattle cans but that's for another video.
When sanding, I would HIGHLY recommend wearing some sort of gloves as you really do not want any of those fine particles getting into your pores. I used to have no issues sanding or filing ABS prints but now I get a reaction and get very itchy so wearing gloves is a really good idea.
It's not always an option, but I prefer to try to design and orient my prints in a way that they'll look good with the layer lines being visible. I've also found that matte colors hide those lines quite well, so that can be a consideration in the material choice. Playing with top and bottom infill patterns can also enhance the look of a "raw" print. Having said that, most of my prints have so far been fairly utilitarian, so they don't need to not look like 3D prints. What I _have_ been doing is adding design flourishes that make a print look nicer: chamfered or rounded edges, shadow lines, embossed or debossed patterns, text or logos, that sort of thing. I've learned a few simple tricks (most of 'em on this channel) that do much more to improve the look of a print than any amount of sanding and painting would. As long as you're not deliberately mimicking the look of something else, like you would with a prop, "designing for 3D printing" can also mean taking the esthetics into account.
Most spray paints that advertise they work great on plastic, have a heavy acetone base (at least in the US). So any plastic that can be dissolved by acetone, like ABS, will not only get a great bond, but smooth and bulk up the surface slightly. It’s not effective on other plastics like PLA and PETG. It’ll still stick like paint. But you’re not getting the same bond and none of the smoothing.
If you have seams from joining multiple parts together, I highly recommend using a watered down wood filler to paint over both surfaces and sand down to make it look like one continuous piece. It is way cheaper than glaze, doesn't have any fumes, and sands SUPER easily so you can be pretty liberal in your application. I would reccomend Dap's Plastic Wood as a starting product to compare to (I know it is in the US, may not be global). Additional tip, add the wood filler to a disposable container and then add small amounts of water and stir until it becomes easily smearable. Add very little at a time, it takes less water than you think and you want it to easily spread, not run.
Just making a little prediction: once techniques like these are ubiquitous just wait a decade or two and we will get soooo nostalgic for that 3d printed texture. I bet if we have printers that don't have that texture by then, people will start using effects that'll bring it back into their prints.
For TPU I can get rid of all layer lines by heating up some kind of rounded smooth clean metal like a screw driver. Heat it up to about 70 degrees on a stove or any heat source that does not make soot. And rub it back and forth over the print really REALLY fast. Like moving your arm back and forth 10 times a second. But just let the metal lightly rest on the TPU while it’s whipping back and forth. Feel the surface and see where it needs more smoothing in bursts of like 5 seconds on. 10 seconds off: it slowly melts the top layer completely smooth without changing its shape or anything. It really is just the layer lines that go and I print at 0.28.
You can get a temperature controllable soldering iron for less than 40 dollars which could ease that process, too. It's the method I've been practicing with, with the bonus that it allows welding parts and adding material via scrap or raw filaments.
@@Dr.Fluffles yeah I have a high end hakko that I kept a spare rod just for that but I found it oxidised too quickly and solder on there obviously wouldn’t work so I find it need to be stainless steel.
I’ve been using sodium bicarbonate commonly used for removing smells in refrigerators with 3d resin to thicken it up. I got the idea from when I used it with crazy glue to make it harden faster.
A rule of thumb is to always use a lower grit before painting if your paint is thick, the paint will fill in the groves and leave a surface finish comprable to high grit, but it will stick much better. Generally you should only use a very high grit (>300) if you are going for a polish and not paint on top.
Acrylic gesso can be a good option if you want a smooth surface quickly. The surface needs to be sanded rough first and I recommend water sanding. PLA in particular will clog the sandpaper in no time. If you use an ordinary brush to apply gesso, it is easy to leave brush marks. I don't know what the right word for the technique is, in Finnish it's called "töpöttäminen" but the idea is to stipple the surface with gesso. I recommend a foam brush or a wash sponge, a magic sponge gives an even finer texture. This leaves a smooth texture that can be sanded even smoother. Depending on how thick the gesso is, a few coats are enough and you can apply acrylic paint and acrylic varnish in the same way.
If you want your PLA parts to look and feel smooth, without loosing the initial material colour, here's what I do. First I file down any rough spots and layer lines. Small metal files work quicker than sanding paper. Once the part looks smoother, but still has medium to small imperfections, I coat it with a thin layer of CA glue. CA glue is inexpensive and dries quickly. Don't inhale the fumes! Once dry, the CA glue layer needs to be sanded back almost completely, like you would automotive body filler. You can work your way up through the grits from 150 to 400 or even 600. You'll be left with a super smooth, mat finish and the PLA colour is still very similar to how it was at the beginning. If you want the part to be glossy or semi glossy, you can optionally spray-paint it with an appropriate transparent top coat.
I have been thinking about using CA glue this way but never got around it to actually applying it. My go to brand of CA glue is sold in tubes so I wasn't sure how to apply to large surfaces. I only recently discovered a new CA glue brand that comes in small bottles that has special brushes.
I've tried the CA glue on some smaller parts with 0.05 layer height and it works well. The cheaper the better as you want stuff that really liquidy and doesn't activate too quickly.
I build droids, and agree - if you want something to not look 3D printed, sand it smooth and paint it. A couple of tips to build on your suggestions: -Print your parts with thicker walls if you're expecting to sand them. You need to have enough "meat" in there to sand it smooth. How thick those walls need to be depends on the accuracy of your printer, because a less accurate machine will need more sanding, but I'd suggest making sure you have at least 1.5mm to work with. On my parts I tend to be cautious and print with 2.4mm thick walls. (Also for strength.) Connected to the accuracy part, slowing your printer down so that it's more accurate will save a tonne of time sanding in the end. -Spray paint is paint mixed with a solvent. Carrier solvents can have weird reactions with plastics. When you first use a new type of paint on a new type of plastic, TEST IT on scrap. It's unlikely in the modern world, but I have in the past had spray paints dissolve a piece of plastic, or just refuse to cure - I have a plastic ball I painted silver 20 years ago that *still* isn't fully cured and is tacky to the touch. A good layer of primer will usually avoid any problems, but better to test your paints than ruin your parts. (Layering paints from two different brands can also have weird effects and you should test that, too.) -PLA is the most rigid plastic used on hobby printers, and consequently the most difficult to sand. ABS is relatively soft and much easier to sand. It's my experience that ABS is about half as much work to sand smooth as PLA is. So if you're doing a lot of parts that you're sanding and finishing, and you have a printer that will handle ABS reasonable well, it's worth the effort to learn to print it.
That old smoothing prints video was the very first video of yours I ever watched shortly after I got my first printer. I too am a huge fan of the MTN Hardcore line, including that exact orange. I painted one of my drone frames with that.
Not that it's a problem in OZ but here in NZ where it's a bit cooler I'll get a bucket of hot water and heat the cans before spraying, been doing this for years with my car parts. Pro tip: Get a magnet and use it to hold the can upright so the nozzle doesn't get wet. When you grab the can just pull it up and the magnet holds against the rim of the bucket and falls to the floor as you remove the can saves time pulling it off. BTW been watching you for a few years now strangely ever since I got my 3d printer. Thanks for the great info!
I recently used corn flour as a resin thickener on my model boat for corner fillets. It might not be ideal but it worked very well in my scenario, is super cheap, easily sourced, isn’t carcinogenic and it sanded very smooth. I was going to use baby powder but it’s full of perfumes and what not. The only thing you need to be carful of is corn flour water absorption. If it’s container is left open it will absorb water from the air severely contaminating the resin.
Very interesting video. One thing you forgot in your PPE was gloves. Wear gloves to keep you hand body oil of of whatever you plan on painting (never bare hand touch the part your going to paint after using wax & grease remover). You can wash your hands but you'll still have normal body oil. Thank you for the informational video
I thought it was just me that hated the layered result of 3D prints so I appreciate the advice and experience. While enclosures and other utility objects or parts I spray with PCB conformal laqueur to make them stronger and more waterproof (I don't make much else TBH) when I do something decorative, like Minecraft models for the kids, it's nice to be able to finish them off to look like a bought one. Thanks Angus, and all the best from Perth. 😄
As an alternative to Talcum powder, I use baby powder. I haven't tried cornstarch, but I have read of others using it. You can still get talc powder, it is helpful for laser engraving on reflective surfaces as it lets the camera pick up the object easier, so it is not completely impossible to get.
At my university we had a industrial resin printer (top tier for ~2012) and during one group project we realised that the resin could be polished to look like glass if we took our time. The four of us spent a week taking it in turn to sand from 120 grit all the way to 3000 grit, then use 3 stages of buffing compound to crate a clear "glass" kettle and a "polycarbonate" visor/air deflector. The end result was amazing but god it was awful on our bodies 😆
That spray putty is something I've never seen before! One chemical combo I've seen a lot of people use is wood filler and acetone 2:1 which creates a similar sand-able surface
I think it's very situational. There are parts and geometries where it's very attractive. In cosplay though, 3d printed parts are generally meant to imitate another material, and the texture is a dead give-away. Also, even when the layers look good, the seam rarely ever does
I use elmers wood putty which is water based so you can thin it to the consistency you want with just water. Then apply with a plastic paddle or paint brush depending on the consistency. It dries in about 20 minutes so you can do multiple coat/sand layers in very little time. After I get it to where I want I spray with rustoleum 2 and 1 primer/filler then do a damp sand, I say damp as you don't want a ton of water or if you sand through the primer/filler it will reactivate the wood putty.
I usually keep two UV resins on hand for smoothing prints. One right out of the bottle for fine detail and another thickened with cornstarch based baby powder. I have also heard of people using fumed silica for thickening resin but I have yet to try it. Another handy filler is Bondo glazing and spot filler. It's an air cured putty. It can also be thinned with acetone to be applied with a brush. The acetone also helps it cure faster. Both UV resin and the spot filler can be further smoothed with sanding.
I personally think a spot putty (like bondo) is a better alternative to the spray version you used. No aerosol, so PPE isn't AS big of a concern. And it's so easy to slap a little bit onto a printed part, and smooth it over in a matter of minutes. But, some form of sanding and filling will almost certainly give the best looking finished product.
particularly for larger surfaces, the best thing is "spot and glazing putty" used in automotive painting. Dries really fast and is the same sanding ability as primer.
I've been doing some printing lately using Polymaker CosPLA filament, which is designed to be easier to sand layer lines out of than regular PLA. It does seem to work pretty well for parts that have large surfaces without a lot of detail, but I've found that small details can get lost easily if you aren't careful with how you sand the part. It's also only available in a neutral grey so you'd only be able to use it on parts that you're planning to paint.
I tend to sand a bit less initially and fill the layer gaps with automotive glazing putty. Small parts can be hard to sand on so going for something that builds up to the peaks of the layers gets the part smoother faster. Then a high-build primer to start making it better. A really smooth prime layer makes the paint job much better.
If you're set up, acetone vapour smoothing of ABS prints is simple, low effort and the prints come out beautifully. You don't need elaborate gear - the chamber can be an empty soup tin on a non-stick baking dish. In short, my recipe is 15mins @ 30C in a low pressure 'chamber' followed by 15mins drying at the same temperature. Full recipe follows... You need * Set up outside if possible. Follow basic safety procedures. * A consistent temperature environment is essential. A low temp oven is ideal, but you can use a printer heated bed with a box on top, or a little garden seed raising box. Just check it thoroughly to make sure it doesn't have parts made of ABS, or ... you will be sad. * As mentioned, the chamber can be any empty steel can. Inside you need to attach about three layers of paper towels with magnets. You can also use polyprop or pet containers, but they are less convenient because you need magnets inside and out to attach the paper towels. * Cheap non-stick baking dish for the 'stage'. Make sure it doesn't have a logo stamped in it - you want a completely smooth surface. The chamber doesn't need a perfect seal on the stage. * Make sure your oven, stage, chamber and print are all very clean. Any bits of dust etc will be permanently embedded in the print and look ugly. Procedure * Place the baking dish/stage upside-down in the 'oven', and preheat to your set temp (I use 30C) * With a large eye dropper to soak the chamber paper with acetone. A soup tin sized chamber will use about 10ml. While the paper should be soaked close to capacity, ***there shouldn't be any free liquid acetone in the chamber***, it causes problems. * Put the print on the stage, cover with the chamber, being careful that the paper towelling doesn't touch the print, and wait your set time (15mins for me) * Remove the chamber, don't touch the print, leave it for your set drying time (again 15mins for me) * The print should just come off the stage and you're done. * Depending on the shape of the print, you can get an all over effect by smooth, dry, flip, smooth, dry - takes about an hour all up. The main trick is that it's very sensitive to temperature. So, standardise your temperature low as you can go. Then to adjust the effect, change the set times, rather than playing with temp.
If you want a glassy smooth finish, I highly recommend wet sanding with a high grit sandpaper after a couple coats of primer. You can also wet sand clear coat if you choose to use it.
0.06mm layer height and the 'Gunze Mr Surfacer' works great on smaller prints. I use it on DnD terrain, fills in the layer lines good but keeps the detail I want. No sanding! They just released a water based one that I'm hopefully trying tomorrow.
All finishing is a lot of work at the end of the day. I've only bothered to do it properly a couple times but it does look great. Choosing the right filament can make a difference too. The piece I'm most proud of is the popular Trex skull model you can easily find online. I printed it in wood PLA, sanded it, stained it, then prayed with clear varnish and it came out looking great. You can barely tell it's 3D printed. My only regret is I didn't think about the PPE and microplastics till more recently and I did most of that work completely unprotected!
I dunno if we have spray putty here in the US (someone let me know if we do!) but my go-to has been Rust-Oleum 2 in 1 filler primer spray. I prefer wet-sanding using blocks instead of paper and i usually go up to 1500 grit block in areas where I need a super smooth finish. Lastly after painting, spray a clear-coat on for protection and those come in matte, satin, or gloss so choose the one that matches whatever finish you plan on needing Thansk for the great video Angus!
@@MakersMuse the nylon powder fused prints like you used to get from Shapeways. A heavy coat of primer , pour on a thin layer of CA glue spread it around to liquify the primer which you can then rub into the stepped recesses. It cures in a couple of minutes and is sandable. Only takes a couple of coats.
I can recommend luthier scrapers and mini luthier scrapers, for PLA, you can scrape off a lot of lines quickly, which makes for a whole lot less sanding.
For anyone in the UK, I use halford knifing putty to smooth my prints, £3 a tube and it takes roughly 1 tube for a mando helmet (maybe a little more if you go crazy)
I haven't really post-processed any of my 3D prints so far. The only exceptions being sanding a few edges to make things fit a little better. Most have been utility prints (drawers, scrapers, AMD parts, etc) and don't matter for appearance. The few display pieces I've done are mostly Stargate space ships, and the lines almost kind of add to the aesthetic. The crisis crossing directions on the F-302 wings as the sloped edge printed kind of looks amazing, with how the different layers catch the light. Atlantis is my next big planned print though, and that can't remain a single uniform colour like the grey ships have. So I think I'll put at least some of these tricks into action for the many towers on the city with their many windows and coloured border sections, rather than trying to print too many of them using multi-colour printing on the AMS. So I've bookmarked this to come back to when needed.
Thnak you for a video! The best resin filler is kaolin. It is the clay used to make ceramic tiles. Unlike talc, calcium carbonate (marble) and the like, kaolin absorbs resin in its pores [this contributes to a much greater thixotropic effect. The only problem is that you can't use a white coating because it stains the resin.
Like the slicers have a seam smoothing option in them. It's actually pretty good, you'll still need to finish your print by hand but by simply enabling ironing it can remove a lot of banding for a small time cost.
I don't know if I'd call ethyl acetate dangerous, anymore than brake cleaner or any other solvents commonly used around households. It's flammable and you don't want to breathe it or spill it on yourself, but it's fairly innocuous.
I tend to do more abs prints since my university lab has a ton of it lying around. And my favorite way to make it smooth is just hit it with the soldering iron like I'm spreading butter. It works well when the layers are thick and coarse but when it's really fine it's usually unnecessary. Then just sand and file it, then brush some acetone once or twice over the surface to get that shine. If you get good at the soldering iron "spreading" you can get the same results from a .4 or .5 layer height than a .2 or .15
I don't know if it would work for 3d prints, but Citadel's Chaos Black is what I use for models. That stuff is strong. If I mess up a coat above, I can generally just sand through and 90% of the time, the base coat is preserved.
from what I've seen talc powder still is available, though I think using a water-peo* mix mixed with water soluble resin might give good results, I'd have to try that. (I'd try mixing ~2.5g with 250ml water and 1L of resin, though it would probably be a good idea to do some tests with smaller batches before, varying the water and peo amounts.) *peo is easily available as PolyOx WSR301, J-lube and X-lube, it's often used for soap bubble strengthening, and obviously its original purpose as a general purpose lubricant. note that relatively obviously you might find NSFW results when searching for both *-lubes.
You can use Primer Filler all in one (no need for separate spray putty and primer) Don't use enamel-based paints, use acrylic. Quicker drying, far less chance to react. Best is not to flog on the filler, as you can end up with solvent boil, spray a coat on, let it flash off, spray another coat. Do about three coats. I would use finer sandpaper, then what you have suggested, as you can get what is called "sink back" where over time the thinners fully evaporate over time, and the paint and primer sinks into the larger cracks.
I found that wet sanding pla prints avoids heating up the print and no dust either. Car shops have a good range of that type of sand paper in rough to very fine grit.
They sell these scrapers that just look like flat metal plates but the edges of them you can form into a small bur and scrape the part, it basically makes it so smooth when you scrape away the material versus endless sanding. Then you can probably do your finishing stuff after and make it look like a injection molded part. less sanding more quality and faster!
TBH although there are occasions where I had a desire for smoother prints (looking at you, slopes...), I really REALLY like the aesthetics of 3D printing, especially on vertical walls and chamfers. Sometimes I even increase the layer height just to increase layer line visibility. I used to think otherwise but when you tuned the shit out of your printer and the perimeters are very consistent, they actually look gorgeous.
I have experimented a bit with making ABS solutions in acetone and coating PLA with them (a brieff dunk and letting them dry in open air). I really liked the result, no or minimal detail loss and a nice glossy finish. Although you could kind of faintly tell that the layer lines where there. I believe that tuning the concentration and maybe sanding could fully remove the layer lines with no detail loss.
I’ve been using an 50/50 mix of acetone and blade putty for an initial paint on. I let it dry sand then use spray putty, been getting good results on helmets
If you're looking for a thickener for your resin a favored technique with woodworkers is to add fine wood powder. I would think the same would apply and it would make the surface easier to sand and wouldn't require as much sanding to get the desired finish.
I've used the Proxxen Pensander on all types of plastic and it works great. I'm sure you could melt PLA with it if you tried, but it doesn't under sensible use and just sands perfectly.
Millibutter: a crater of milliput and IPA. Mix. Good for a lot of things. Also use a surfacer like Mr. Surfacer with the "grit" numbers. Also with FDM you can scrape the surface and then sand it
I know it's isopropyl alcohol, but literary every time I read these comments I have a temporary moment where I think someone is recommending the use of beer
I've done the same but I found it REALLY easy to scratch the paint on part and it ruins the whole surface. I'd suggest using a few coats of matte or gloss clear lacquer to finish it off. I've had good results from Tamiya.
If you are remaking an Injection Molded part and have access to the mold in some manner, you can rough out the part in FDM and use the mold to forge the part into the final shape.
I still use acetone vapor for ABS parts, especially if it's something that I will be holding, like a game controller. For things like this, paint tends to rub off eventually. Having a clear epoxy over parts might be a viable alternative. I haven't gotten around to trying this yet.
I've found that quickly hitting a print with a foam sanding pad and then polishing it with a wheel on my Dremel is often adequate. Less effort than a full fill and paint treatment, which I've only done once for a shower knob (ironically, it was only supposed to be temporary, but my friend liked it so much they asked for a permanent version).
For resin printed support nubs I have a set of riffler files. They work quickly, give a decent finish to work on and best of all their shapes let you get into nooks and crannies. Don't get cheap ones though, definitely worth investing on at least a mid range set.
One thing I've figured out over the years is if you want a super fine polish, give your piece a clear coat and hit the surface with melamine sponges (magic erasers) they're amazing for polishing so long as your clear coat is fully cured.
I don't 3D print but I do polish plastics sometimes for the smoothest finish. I use Meguiar's Water Spot Remover I bought for my car and ended up using it everywhere, even when it's not aggressive I've used it to polish some metals, though with a enough patience. Greatly recommend it.
3M filler for plastic (green stuff in big tubes) dries really quickly (a minute or two) and sands incredibly easily. I find this si much faster than the spray filler approach for smaller sites, but use the spray filler for larger ones
I have been using the UV resin trick it gets close to a mirror finish on some parts after some wet and dry sanding. The alternative to powder is some people have talked about using flour. I have not tried that yet but regardless you have to do multiple thin coats so you can cute with a light as you go.
6:05 I don't know if there is a specific english name for it but I use corn flour for this. It's especially very useful to fill holes in hollowed models.
Corn starch! You can buy regular corn starch in the cooking isle (it is used as a thickener for sauces and soups), but most baby powder is now made with corn starch as well, and for bulking up resin it works just as well
ooor, and hear me out, use a resin printer, even a smaller one, and break the piece into parts, then coat that with primer, then color, then varnish, using an airbrush, and you only have to leave each layer to set with a small desk fan for 30min-2h depending on how thick you're spraying. but I don't know whether you can get a proper glass-like finish with this, but it's a very smooth start, and can preserve very well the details
I usually use the bumper filler from Autobahn but they were out of stock recenlty so i used the one you have in your vid from Super Cheap. It worked great but it reacted with parts i had super glued together and made them come apart, sometimes with a quite audible crack. I've also found timbermate wood filler is great fro filling in bigger gaps and joins before priming and sanding. Much easier cleanup and use that bog.
Haven't read all the comments but something I use as a thickener for adhesives when working with prosthetic makeup is cab-o-sil. Horrible stuff to breathe in (wear a respirator) but it's fine enough that it should probably be good for thickening resin.
There's these electric dead skin files for your feet that have a nice low rpm and often adjustable speed so they don't melt the plastic from excessive friction and you can use double sided tape to stick any grit sandpaper you wan to and if you've got a lot of big flat prints to sand for cosplay or whatever it's the best $15-30 you can spend. I used a foam pad of 400grit to smooth out between the ridges of a vase I printed and it came out really good without ruining the ridges or taken tens of hours to sand.
tbh going way bigger to like 1.2mm/0.6-0.8 layers or more can look great, but also going down with resin looks good though I do like the way removing a few degrees off of flat looks with fast resin (like 0.1mm) for industrial/low poly things, it makes nice bands. going with the material can give great results, and while it's easy to not bother and just smooth it, and it gives decent results it's kinda like putting an opaque coating on wood.
There's another type of melt smoothing, that even has the benefit of being able to add material from scraps or raw filament to prevent deformation and weld parts, and that's thermal via soldering iron or another controllable heating tool, but it takes practice. I've had good results welding broken parts back together, and with small areas of smoothing, but it gets difficult over larger areas with a standard bit. I suspect flat woodburning bits would fair better.
