*TO CLARIFY:* What makes this huge boost to the print quality is printing the OUTER WALL before the adjacent INNER WALL is printed. That is why I called the Inner/Outer/Inner wall ordering option "printing outer wall first" as it does exactly that. Hopefully, that clarifies things. I know it can be quite confusing. *So TLDR:* Inner/Outer = IW first Outer/Inner = OW first Inner/Outer/Inner = OW first

This is the first video whose title contains the tired, old "GAME-CHANGER" claim that actually turned out to be a game-changer for me. Printing the outside walls first made a MASSIVE difference in the quality of my prints. I've been living with semi-OK prints for literally 3 years...can't believe I've gone this long without knowing about this setting. Why isn't it on by default in all slicers? Edit to add, after another print: I seriously can't believe the difference this made. My print looks almost injection-molded, for cryin' out loud! And I'm running it on my trusty old Ender-3 V2. Unbelievable!! Thanks for this tip!

I discovered this a few years ago. I realized that the quality is massively improved and there is pretty much no downside. I am really surprised this isn't standard.

Finally, I've been printing OW first for 5 years now, saves a lot of time on postprocessing too

I started using IW/OW/IW because of the scarf joint feature and it was surprising to me how much better everything became, but I couldn't put two and two together on how that could be so until your video, thanks!

One likely reason is that curling and warping are caused by outer layers not having sufficient time to cool combined with the contraction of inner layers as they cool pull in on the outer filament. So by printing an outer wall first, you’re giving the outer layer the most time to cool so that it can be already solidified by the time the printer gets around to it. I legitimately never thought of it like that.

Well done for showing this in your prints, I kept switching between Orca and Bambu and got better results, but never realised what settings I changed as I discarded them. You've jogged the memory cells thank you :)

I had great results with these settings as well, though admittedly with limited testing. Most of the improvements make sense. I realized one reason the overhangs being as good or even improving may make sense while watching for video. First of all, the filament has more room to expand and sit on top of the previous layer, since it won't hit the inner wall and then have to squish outward over the side, which could cause a drooping overhang. Sure, you may think because clinging to the inner wall would keep the filament from falling outward that it would help, but the volume of filament extruded all has to go somewhere, so outward is the remaining direction if the inner wall is present. The other reason I think it may help is that not having an inner wall means the outer wall extrusion can be cooled from both sides, it even has a little channel of air flowing past it, and it isn't being kept warm by the previously printed inner wall. I would suspect the added cooling is a much larger factor than residual heat from an inner wall, but the amount the latter varies would depend on the print. I wonder how much outer wall appearance would vary with line width as well, especially with overhangs. Also counterintuitive, but wider layer widths can actually give better overhangs because it insets the outer wall more on the previous layer, meaning the center of the nozzle is less in free air when extruding. Anyways, very interesting tests and results! I do think I saw a slight improvement in your tests with the precise wall setting on, as especially the lower ridge on your far right test print was smoother. Hard to say not holding it though. A combo of outer wall first, precise wall, good cooling, and perhaps even wider than nozzle width layers could be the ultimate combo. Beyond that, precise extrusion is so important, as you repeatedly mentioned. This seems to be the Achilles heel of the K1 series, for example. Once you get extrusion dialed in, testing all of the other settings reveals a lot.

This solved all my outer line line problems, I thought it was weak cooling . I`ve never suspect that is the wall order so much important for print quality !! Thank you so much for sharing your experiments !!!

I've been trying to tell folks outer perimeters first is better for years but everybody looks at me like I'm crazy...

You earned a new subscriber with this one. Super fascinating idea, to-the-point video, and a good comparison of results. Well done, keep it up! Excited to check out the other videos on your channel and see what else you have in store in the future. Going to give I/O/I walls a shot on my printer right now!

Awesome to see the results really looking better and better! Congrats! 👌

this may be the final piece to my layer consistency journey, I avoided this bc of the stigma against it for "bad overhangs", thank you!

I just recently got into 3D printing and switched to this method after watching your video. Made all the difference in the world. My prints look so much better. Thanks!!!

Great video! I have also been using this setting for a little while now and it’s great. Thanks for the video.

A while ago, I've also started printing infill before walls (infill-outer-inner), so that any points from bad pressure advance get kinda ironed flat by the head moving by. Might be cool to try as well. Awesome stuff as always!

Wow im going to try this now. It makes a lot of sense after watching your video. Thanks!

2:26 Thank you so much for this small piece of information, I already knew printing outer walls first improves quality, but this problem you are discussing here is also super important, while almost nobody seems to know about it.

Nice find, going to try it tonight. Just found your channel, and it’s fantastic! 😊

I started using Cura two years ago for the ultimaker 2+ connect I borrow from time to time and it had outer perimeters first by default. I was amazed by the quality and dimensional accuracy

VERY INTERESTING. ALWAYS LOOKING ON HOW TO IMPROVE PRINTS. I’ll have to try ORCA SLICER

Just a note on the "prrecise wall", and why it didn't change much: it's intended purpose is to improve dimensional accuracy, which is the aspect I usually care most about. It's nice if it looks pretty, but I most of all want it to work and fit correctly. For that precise wall does exactly what it's supposed to, at least for me. Much less deviation.

That's awesome, I'm gonna try! I appreciate you included the comment about the tradeoff as well

This small change gave me the biggest improvement of quality from all the changes. Including extruder/hotend/rails/kinetic bed. I don't need to upgrade anything anymore, and prints are superb, even under strong top-down lightning

Great video thanks for the advice!

Thankyou for this, I really mean it. I have been having issues with My K1 Max for months, tried everything. I used your suggested wall settings and the 2 mm thing and pow! My print layer lines have finally gone

Neat slicer trick. This made my layer lines on CF-PETG look massively better.

Thank you! Never heard abou this before. Cant wait to try it.

Thanks for sharing! Ill give er a try

Wow! The quality of my prints are so clean!! Thank you

I have been enjoying your videos for a while now and you appear to be a fellow engineer. So it was time to pony up and join as a member to support you. I hope these types of videos keep coming and that others follow my lead.

One of the best "3d printing tips" videos, thank you

Thank you very much for this video. I had no idea that with this simple option, I could improve the print quality so much. With ESUN's ABS+, the quality improved quite a bit for me.

Great tip! Thanks for sharing!

I am currently printing some printer feet in TPU. The first two were printed with my old settings, second two are printing with In/Out/In, and I can already see a clear difference in quality.

I've had mild arguments with people that refuse to believe that dual gear extruders have any downside.

Note that layer with to height ratio and extrousion multiplier also have a huge effect on overhangs and surface consistency

tested on the bambu a1 and work perfect! thanks mate for this tips

I don't tend to leave comments on videos, but I'll make an exception here - I had bad looking walls for a while now, and haven't thought about changing wall printing order. I just changed this simple setting and printed the best looking piece I ever made. Thank you so much!

same! for me when printing really fast, its even better for cooling and overhangs. Another thing I miss and am very confused by, slow down inner walls first/only. that way you will get a consistent surface finish even when slowing down for minimum layer time.

Gonna try this today!

very useful, thanks!

I'm testing this now and hoping for great improvements to dimensional accuracy for my Clickfinity Refined plates. One note: the description of the travel distance threshold is not clear at all, and since it's the most replayed part of the video I'm not the only one. I read around and from what I can tell from your video is that you have a travel distance threshold of 1mm and a Z hop type of Spiral. This causes Z-height movements when moving to another wall > 1mm away, slowing your print times (and probably heating up the filament more during that S hop time, causing dimensional issues). You recommend increasing the default to something like 2mm which reduced your print times. But this is only true because you have a Spiral Z hop type vs Slope, which combines Z movements with XY movements to reduce stringing. For me-Bambu Labs P1S w/0.6mm E3D ObXidian nozzle-the default value (under Printer Settings » Extruder » Retraction » Travel distance threshold) was 3mm with a Z Hop Type of Auto (aka Slope), so this is not applicable to me. Z Hop defines how the print head combines Z movements alongside XY movements. Keep in mind that some users are seeing scraping when the travel distance threshold is > 0mm. If this is the case then Z Hop Type to Normal might help at the cost of longer print times. The bottom of this Github issue is a great read for folks who want to learn the pros and cons of these settings: github.com/bambulab/BambuStudio/issues/3423

Just re-printed a Raspi case I found yesterday, but with OW. All the long straight surfaces came out much smoother, but the narrowest sections around the I/O, and the poles for the self-tapping screws came out a little bit bumpy. So a little bit hit and miss without any additional tuning, which I'll look into. So far I'm quite impressed. I've ignored this setting because I haven't really had any issues with tolerances and that Prusa Slicer has that tooltip that says it would reduce overall quality...

For tight tolerance or for quality surface I always use outer wall first but depending on the finish I need 0.4mm outer wall with 0.07 layer height and 0.7mm infill with 0.2mm layer height to make up for slower perimeter speed. This works great for overhangs and surface finish as it prints 3 layers of outer wall before 1 pass of the infill. This is done with a 0.6mm nozzle.

Been usong outer wall first for a while. Definitely well worth it. Minimal infill disturbances shown on the outside. I have one model that I sell as a physical process where itnis causing me issues due to overhang. I wonder if i can do a local section of inner wall first just in the overhang area. Could be interesting to explore it

A lot of my recent prints have had some decent overhangs, which has always prevented me from using sandwich mode out of caution - guess I'll have to give it a go once again!

Thank you for your work. For me Inner outer inner walls is slightly better but the seams are less beautiful. Have you changed the seam settings?

I first noticed this while tuning print settings for a large format printer at work but completely forgot about it after I started using Bambu/Vorons because the print quality was always good enough

Ok. TESTED. Using the Built in Orca Tolerance test, I am able to get the hex key into the .05 Hole. Previously, I was only able to get down to the .2. The only change made to the printer was changing to Inner/Outer/Inner.

I have the same issue with my prints so I will try this.

Ngl I thought this was just going to be some clickbait but damn, the proof is in the pudding!! You’re right it does seem counterintuitive. I’m going to try this out for myself but it’s hard to deny all of your testing and obviously clear results. Great job on enriching our community. Damn near perfect prints ahead!! 😎

This may be my solution ive looked for.

@DIYPERSPECTIVE May i ask what measurement unit is for you in overhang printing example of ABS on X1C, are those 10 % or mm/s for Bridge/External, and 50 are % mm/s for Bridge/Internal speeds? (And at what max volumetric speed you usually print ABS on X1C, if those are %?)

What is this setting in Prusa slicer? There’s a box for “external perimeter first: print contour perimeters from the outermost one to the innermost one instead of the default inverse order.” Is this the same setting?

Some of my best prints came off a Kossel Mini I built way back in 2014 that had a bearing for idler vs driven hobbed idler gear. That said, I'm not a big fan of concave hobbed drive gear or idler, because the filament can walk up the sides of the idler and/or hobbed gear which essentially changes the gear ratio, think CVT transmission and the filament is the belt.

Thank you for the helpful video. Do you have the solution how to get rid of wall bulge at transition from base floor to wall?

This is great, subscribed! Question: At 3:33 at the bottom of the page shown, it says " When this feature is enabled in OrcaSlicer, the overlap between the outer wall and its adjacent inner wall is set to zero. This ensures that the overall strength of the printed part is unaffected." It seems to me that there would then be little or no adhesion between the two adjacent lasers and thus the part would be weaker.

Question: New to Orca. Ender 3 Pro/Duet I ran the temp tower (PLA) from 195-230. really can't see a difference. Then I did first pass of Flow Calibration, and frankly they all have very nice top layers? I can't really pick a best.

That seems extremely helpful, i will try it out next since i have problems with part fitting... even though i must admit that i am using an 0.8 mm nozzle which could also affect the overall thinkess of the part walls. Thank you anyway for the recommendation. :) *Edit: I also want to ask something else depending on the settings I usually use. To be more specific, I am using a much lower printing speed for the outer walls vs the inner and the infill, do you think that this is for the better, doesn't matter? or does it make things worse?

I may give that a try on my Ender 3 S1 with the Zuff cooler.

The seemecnc ezrstruder has one gear and works beautifully

You make good job!

Since you talk about surface finish, have you ever read the article called "Filament Width Compensation Experiments"? (Links not always allowed in YB, no idea why). It uses a Hall effect sensor to measure filament diameter and Klipper compensates for it. And you know what I found out today? The Q1 pro has a filament runout sensor on the extruder which is not a simple switch but actually a Hall filament width sensor! Just it's not used as diameter sensor, only as runout. Maybe you could try to calibrate it and enable it to see how it performs, if it helps or not. The author of the article writes that with that sensor he basically doesn't need to fine tune the extrusion multiplier for each filament, they end up all at about the same value.

Most of this has been my experience also. I can't speak to the overhangs though. My overhangs are better than before, but I cannot say for sure that it's because of this setting. I didn't notice it right away, but that's probably because I didn't immediately print things with overhangs before and after making the change.

on my voron, when i want to have really good print quality, i use my hyper speed profile (700mm/s 50k accel) and limit the flowrate to around 20, so the whole model has the same flowrate in the flowrate viewer

is this a possible setting on Prusaslicer? i cant seem to find it

Inner out inner is the best but remember overhangs will perform worse, so you need to lower the layer height to help compensate. Also Orca and Bambu slicer do a crap job of converting arcs when using arachne, so run it through arc welder afterwards.

As of my testing I get nearly the same result with precise wall as with IOI Walls and also better overhangs. Also for IOI you obviously need 3 walls. I usually print with 2 + PW

Trying this today on my Bambu x1c I wonder if a benchy would show any improvement.

Gracias!!

Very interesting video. Do you have links to that test object and your overhang test?

how do you do this in prusa slicer 2.7? thanks

Does this apply to PrusaSlicer too?

I'll try that. In Cura it's called "Wall Ordering". Also, if you find a solution for those Bulged lines which some people refer to as "Benchy hull line" we'd all be grateful, since not even Prusa found a solution in their article about it.

Nice tip, thank you! Can you (or someone else) tell me which printer it is at 3:22 ? it looks nice and simple with bed swinger and linear rails.

This setting made me realize how underwhelming the StealthBurner’s cooling is. Moving over to a DragonBurner so I can turn this back on with ABS

does this play well with scarf seams?

Would be great if slicers were smarter and could do outer walls first except when it results in floating sections

One bit of information missing is the difference in settings you were using for inner vs out walls? Would you get these results if both were being printed at the same speed/flow? What is the speed difference you were using here?

what print speeds for the inner and outer wall did you use in the tests?

I've actually had difficult prints succeed using IOI that were failing after several other tries.

I wonder how well it'll work on prusa slicer since it only has outer first and not inner outer inner

Infill before walls or after?

How could you change the wall printing order in Bnabu Studio?

Unbelievable! I get damn near perfect prints now. All that time I spent sanding, spot filler, filler primer, sanding, more sanding...Unbelievable.

Parts shown have IW and OW, but how do they actually translate to slicer settings? Is either of those inner-outer-inner, or is it at all useful?

I'm uysing Cura 5.7 and there settings are a bit different here. Inner/Outer/Inner does not exist but instead "Wall ordering - IO or OI, and also "Travel distance treshold" seems to not be here.

Please do share the extruder mount.

Thanks for the video. I wonder why this is not default.

I do 2 walls, inner first, but then extra walls for infill so I have a minimum of 3 walls. My printer has some retraction ptoblems so I can't use more than 0.3mm retraction so I get some dripping... can't do outer wall first because seam looks like crap, sometimes even has a hole in it...

So suggested one is inner/outer/inner. What about outer/inner setting?

how do i do this on prusaslicer?

Can you share your settings? I used PETG and tried changing the outer wall layer first but the effect did not change

When I use outer walls first I can’t seem to print threads. Threads as in a bolt.

I'm having a hard time believe it, but since you are saying and showing it I do believe. And then I'm having a hard time to understand why is it better. I mean, what does happens to make it better?

Can you experiment with simplify 3d for the bambu labs printers?

I want to try and make this clear… we should use the inner/outter/inner setting? Lmao. This video became a little obscure in the details. Overhangs are bad with this setting, but overall it’s better…?

in bambu studio we call this the brotherhood of the order of walls

Thank you for this video! I came across this setting, probably three or four years ago and noticed the improved quality. In that time. I probably watched over 1000 videos on 3-D printing and yours is the first and only one I’ve ever seen that suggested this setting. 7:27