Design Better Holes | Improve Tolerances | Reduce Sagging | Design for Mass Production 3D Printing

[@hmmccray]

As an engineer in industry, I thought I knew most techniques when it came to prototyping. This video actually taught me more than I would ever get from a KZbin short or tik tok.

[@georgegriffin6114]

"Hassle free holes" was my nickname in college

[@ReplicateReality]

Mine wasnt

[@joeds3775]

No surprise there.

[@joeds3775]

​@@ReplicateReality Also, no surprise there.

[@BRP-Moto-Tips]

hell yeah

[@MatthewHolevinski]

@7:03 did I hear that right?

[@frankbauerful]

I'm shocked you didn't mention the best way to design top holes without support: polygonal approximation. The 1st layer of the hole when coming up from the bottom you cut out a rectangle that is as wide as the hole and as long as the inside of the box. That way there is only clean bridging on this layer, no starts and stops over empty space. The 2nd layer of the hole you cut out a square surrounding the hole. This square is supported by the cleanly bridged layer before it, so again we're only bridging. Usually the long rectangle and the square are enough but you could go on and add another layer with a polygon of more than 4 sides that surrounds the hole.

[@richdobbs6595]

I agree. I've started using this technique that I saw on Maker's Muse, that apparently Prusa uses all the time. In my case I want to have a smooth hole that filament passes through, and sometimes I'm printing with a cavity, with the filament passing out through the top.

[@slant3d]

We omitted that because it is non-intuitive for traditional manufacturing. And often not viable for thin-walled pieces because it changes the dimensions. Also sometimes dependent on slicer settings which we try to avoid.

[@LimabeanStudios]

​@@richdobbs6595can you direct me to which maker muse video goes over this?

[@stast2944]

Thank you for explanation. Didnt knew that. Sounds pretty smart. Will try next time.

[@LukeDehtiar]

@@LimabeanStudios kzbin.info/www/bejne/gXPYiJaKbb2enqMsi=ut1FzH8h9haNf9rh

[@linyongzheng]

Would have been great to mention the caveat with grip fins: they are great for disassembly, but in many 3D printed plastics (PLA), there is significant creep (deformation on sustained loads). This means the force will change (get looser) if the rod was inserted for a long time and doesn't maintain consistent grip strength as mention in the video. Small distinction but important to note for people new to 3D printing.

[@Pokornz]

Exactly, most common FDM materials will creep into the position you forced them to, and because that's their new neutral position, the spring effect is gone.

[@kbee225]

This is true of most polymers in general, if anything below Tg PLA resists this better than some other polymers like PP. But creep is just something you have to deal with when you deal with viscoelastic materials (i.e., most polymers).

[@honkbeforeitstoolate587]

PETG seems to creep slightly, but much more useful than PLA. After petg initially creeps a little, it seems to reach a point where it stops.

[@davebarkerdesign]

who knew making holes for 3d printing could be so varied and dependant on your design intent. As always, great content!

[@slant3d]

Thanks

[@andrewb9774]

This is probably the best video about practical manufacturing with 3d printing (at least for me!) that this channel has published! Solid GOLD.

[@oscarcer]

4:48 We (3D printing community) need to stop calling clearance as a "tolerance". Clearance (or interference for a negative clearance) is how much nominal distance there is between two (nominal=in a perfect world). Tolerance is how much a dimension in a real part can deviate from the design and still function as intended (including but not limited to clearances). Tolerance is how much error is acceptable, since there is always some amount of error. Clearance is the gap. The confusion comes from the fact that we can design a gap to be tolerant to errors. But they are different things

[@InternToCEO]

Are you familiar with ISO 286 tolerance grades chart? I would say it's okay to use word "tolerance" when talking about clearance and interference.

[@pablo321123]

@@InternToCEO um, that chart is rightly named because it's about tolerances. Perhaps you're not understanding what the chart is doing?

[@InternToCEO]

@@pablo321123 I understand what the chart does. I should of not commented about it...

[@davidgeorge6278]

Came back to this video 3 days after watching it specifically to like, sub, and comment. My first impression of the video was that it was okay, but that hole with the fins cut into it so it grips with even pressure has really helped me out big time.

[@slant3d]

We love to hear it

[@rrowhe4d]

This was WAYY too insanely useful for such a short, 8 minute video. Presentation style: 10/10 Examples provided: 10/10 Clear explanation: 10/10 New, useful techniques: 10/10 Subbed.

[@slant3d]

Thanks, glad you liked it!

[@pmarzoccojr]

Thank you very much for the tips and to everyone whom has left great comments. Very much appreciated.

[@arthurmoore9488]

"Maniacal Labs LLC" has a video on how to make some holes without support. The trick being adding a sort of step a layer or two underneath the hole, then another in a different direction. It provides enough support that the hole itself doesn't have a huge amount of filament hanging in mid-air.

[@jizhang2407]

The raindrop-like hole is a functional and beautiful idea 👍

[@andybrice2711]

In my experience: For holes in vertical faces like 1:20, rather than using a teardrop shape, you can just use a decagon (with horizontal edges top and bottom).

[@phasesecuritytechnology6573]

interesting idea

[@larrybud]

Do you do this with any size hole or up to a certain size?

[@andybrice2711]

​@@larrybud I'd say the decagon approach is best for mid-size holes, in the order of several centimetres. With holes under a few mm, you can often just get away with circles and several layers of steep overhang. With much larger holes where you can no longer bridge across the top, you might need a different approach.

[@logicalfundy]

When printing spare parts for my Mk4, I noticed that Prusa puts a notch on top of their holes. Kind of the same idea as your teardrop shape, but easier to apply to larger holes. They also like to use hexagons if they can get away with it.

[@professionalelectronics3158]

It's a very classic shape for old school RepRap projects. I believe it's even part of their logo.

[@nicholasweiss4662]

That second tick of making holes tear drop shaped is genius! Im totally gonna use that in my future projects!

[@andybrice2711]

I think a neater solution is just to make the hole a decagon.

[@larrybud]

I don't get this solution. You go from one deformed hole to a different type of deformed hole. What's the benefit?

[@MrRedstoner]

@@larrybud Instead of deformed to less than full circle it's deformed to more than full. Might be a tradeoff that's worth it in some situations

[@danielcoffaro6569]

This channel is fantastic. Simple to the point content. Every video ive watched has helped me learn a new design tool. Im trying to start a webshop selling parts and its fantastic to hear your thoughts and attitude on the design and industry. Thanks and keep it up

[@michaelbartmann7957]

Very comprehensive compilation of useful techniques. Thank you!

[@mr_voron]

Ok, I have to ask. Did you guys get an order of nothing but electrical enclosures for forever? Or is that just the most common part you get orders for? Cause it’s been mentioned in almost every video.

[@rowannadon7668]

I feel like 30 percent of my prints are probably electrical enclosures

[@Graham_Wideman]

@@rowannadon7668 50% + of mine!

[@tomsmith3045]

These are great tips. Another way to print a top hole that's simple, and requires no extra cleanup, is to either make the hole extend to a cone to the outside edges of the box, or make a 45 degree ramp inside the box that the hole goes into. The disadvantage of that is longer printer time and more material, and that it uses up volume inside the box.

[@chrisf8584]

That would be my approach. Some design a part for a function and I guess others design the part for the function and with the tool that will need to make it in mind.

[@onhazrat]

🎯 Key Takeaways for quick navigation: 00:28 ⚙️ Adding small fillets around a hole helps create a cleaner 3D printed hole and prevents deformation. 01:10 📏 Adding a point to the top of a hole prevents sagging and maintains the outer profile for reliable screw placement. 02:21 🏗️ Unsupported top holes can lead to messy prints; consider supporting or using a sacrificial layer to avoid issues. 03:46 🛠️ Compensate for 3D printing shrinkage by adding a small chamfer at the top of the hole for a good fit. 04:56 🏗️ Design holes at true diameter and add relief features on the outer side to create a strong press fit while avoiding deformation. 05:24 🌀 Crush ribs are sacrificial features that enhance press fits by allowing controlled deformation. 06:22 🔄 Grip fins are flexible features around a hole's outer edge, providing constant grip force for removable and reusable parts. Made with HARPA AI

[@802Garage]

7:22 Almost a HOLE video in and of itself. I see what you did there. Also using concentric layer patterns can help make really nice vertical holes especially chamfered or filleted.

[@JohnVanderbeck]

But I thought this WAS a hole video :p

[@lemguins7031]

For top holes, there has to be some sort of software support to force prioritizing filling in the corners, from walls, to adjacent ones, until an octagon is made first. Then spiral fill in an octagon shape until the hole can be cleanly shaped, to reduce bridging distance on overhangs in general, then alternate to a traditional fill pattern on even numbered layers for tensile strength. You'd always have 3 points of support if that could be changed readily: a starting anchor, lateral support and end point anchor to keep the build from sagging while cooling and no curved extrusion for printers that can't handle it. Of course with that being something some can try, any change with geometry would warrant plotting out the best path differently on each build specifically to avoid issues.

[@adamsvette]

I absolutely love your channel. These kind of videos are a wealth of inspiration and information

[@slant3d]

Glad you like them!

[@PaulHopkins-nl2hx]

If you plan on drilling or taping the vertical hole. The 'tear' shape hole will cause the drill or tap to shift upward. You may want to add a bottom 'tear' to create the same forces from the top and bottom.

[@coolbugfacts1234]

I have this exact problem at the moment, I'm designing router bit holders, they need to grip the bit shaft securely but also release without too much force since you don't want to slice up your fingers on the bit. I started with a half circle with two 50-60 degree fingers of a smaller radius to grip, but that design just doesn't have the dimensional flexibility required.

[@sagerobot]

Loved the unintentional pun there at the end. A "HOLE" Video indeed. haha

[@daveroche689]

Excellent tutorial. Makers Muse did the point at the top style a few years ago because you done require supports, when done the right way. The trouble with grip fits is they are slower to print but better than getting the fit slightly wrong over and over.

[@hearthomeacres3322]

For supporting overhanging through holes, the best solution I've seen is designing in a cylindrical plug that is barely larger than the diameter of the hole and just meets the bottom of the hole. This plug provides support to bridge to and breaks away cleanly.

[@larrybud]

You mean a cylindrical support?

[@Rundik]

"Design better holes to improve tolerance" is this a message to god?

[@LucasWestfall]

What tweezer set are you using for spruce removal? I noticed those are a good mix between plier and tweezers. Just curious.

[@5mmTech]

I know the top comment is giving you a hard time, but this was an awesome video. I learned a lot. Thank you for making these videos. It's greatly appreciated.

[@zachsss1916]

I just tried printing a picture frame with holes on the ends to connect four pieces together with pegs, the holes looked awful, thanks for the tips!

[@MaxWithTheSax]

Awesome video. I love that you get straight to the point without wasting any time. Very informative.

[@cattunger]

I'm only here to give my legally required "your mom" joke due to the thumbnail.

[@Hotwire_RCTrix]

Watching this video made me realize the top point of the hole isn't necessarily required. Just enough extra to compensate for the sag.👍

[@bluustreak6578]

As soon as I saw the thumbnail I knew it was gonna be a great vid. These tips are so good, and definitely gonna be used :)

[@TheGlitterMan]

The video is saved in a playlist that may or may not be seen again. XD

[@edoardosoave]

Thanks, your tips gave me new 3d printing ideas!

[@calmarcalmar]

awesome - but .. 2:50 for this kind of hole, you would make a support like that there? It's not clear to me.

[@andyl2201]

Another awesome video thank you 👍🏻

[@scienceofart9121]

Amazing video, just subscribed!

[@SynthaPak]

How would you recommend dealing with SHCS holes where the head side ends up needing to be printed down? Are sacrificial layers the best way to deal with these types of holes?

[@darkracer1252]

these seem to be great video's. they are all basic knowlegde things. but because of that, nobody ever explains them. it just comes natural to me so i don't think about them in this detail. keep making these video's. i'm not your target demographic. but this is going to be helpfull for many many people.

[@Altirix_]

curious, you mention sacrificial layers for printing the floating hole. but what about the method thats common on prusa parts, where you print a single direction layer up to the edge of the circle either side, then another layer going in the oposite direction up to the edge of the circle on either side. then finally print the layer with the circle. you get the benefit of the sacrificial layer without needing to punch through any material. floating holes are just yet another one of those complicated slicer problems that hasnt been cracked yet. in theory doing something similar but in a single layer should be possible, with custom gcode to prioritise the outer solid sections first then use them as supports for the inner walls, while also preventing sudden velocity changes. not sure what would be needed on the slicer side to generate that kind of gcode automagically.

[@SlightMalfunction]

That's a hole lot of good info!

[@kacheric]

Great stuff, thanks for everything you've been sharing, very useful information.

[@Laz_Arus]

This vid added a whole new dimension to my learning. 😉

[@MiiikeeeHuuunt]

What color filament is that, it's nice

[@ObsessiveEngineering]

One thing not mentioned in this video is using fuzzy skin. It's not always feasible since you usually have to enable fuzzy skin for the whole print, but it can help create a nice friction fit while allowing for some non-destructive deformation. Great video, btw!

[@dfoster9445]

Thanks for these vids. They have changed the way I thought about designing.

[@darkracer1252]

06:20 personally. i would do this one the other way around. that way screwing something in is nice and easy. but it tightens when you try to unscrew it. it's a self securing type of connection.

[@Splarkszter]

Wow! Thank you for this!

[@5FSF]

What is your opinion of custom supports? As in, modeled directly to combat specific issues while making the post processing easier than with slicer supports? Is the work-flow too challenging to make something like that per-part? If a modeler is specifically making design choices to tailor to the printing process, couldn't that same understanding be extended to custom support structures?

[@carlosjosejimenezbermudez9255]

They'll always be inferior to no supports. But I would argue that custom supports should be the only supports allowed if you're doing it for mass manufacturing. Generated supports for a one-off or a few more is fine, but not if you need 1000 parts.

[@5FSF]

@@carlosjosejimenezbermudez9255 I've always thought it would be the like, coolest most efficient thing to somehow make a support structure which could also be another part for the object, like if you had a box with a hole in the top and a screw that went in that hole that you could put below it in a way that it supported the hole, take it off the bed twist it slightly apart and have no waste material. THAT is definitely not a viable common thing, but it sure would be neat.

[@Graham_Wideman]

@@5FSF Hmm, I'm going to look for opportunities to try that!

[@jickhertz4124]

Very cool!

[@slant3d]

Thanks

[@collie147]

There's another way to make and unsupported top hole, make a rectangle of one layer to one side of the hole and the opposite side (these are then bridged), next layer up make rectangles left right top and bottom of the hole and then a pentagram for the 3rd layer. Everything is bridged and supported for a round hole on the 4th layer. It's a bit more work but it saves a lot in the long run with repeatable results and no post processing. First saw this on prusa designs and there's a few videos on this by various KZbinrs (Teaching Tech, Makers Muse, etc).

[@freddelgado]

How not to love this? 🤟🏼🤟🏼

[@kitmarshall4084]

depending on application. i'll post processing with a drill bit, and thanks for the relief feature idea, im going incorporate that to my designs.

[@gianlucat_99.16]

Unfortunately, especially for smaller diameters, drill bits may not be precise enough. In these cases you should use a reamer.

[@kitmarshall4084]

Good idea! I’m familiar with tapered reamers, but I think you’re referring to the straight reamers

[@urgamecshk]

Huh? A 10mm drill is as precise as a 1mm drill ​@@gianlucat_99.16

[@TheOneSpam]

Where was this video last week??? lol Such great tips I hadn't thought of! Thank you for sharing :D

[@nimennacnamme6328]

"That is a hole video in and of itself." - I see what you did there :D

[@SmithyScotland]

My mind is being blown by your design tip vids. Loving it.

[@slant3d]

Awesome! Thank you!

[@AaronFergFerguson]

I do .15mm over for a snug fit and .2mm over for a nice slip fit

[@ardenofmoss]

How did I get here? I don't even own a 2D printer, let alone 3D.

[@ktakeshi17]

KZbin knows you like strong holes. KZbin sees all and knows all.

[@ozskeeter]

I wish more people were creative with their "holes" for tolerances ... as a casual user I prefer something that "just works" rather than have to brute force tolerances when I am constructing an item with individual 3D printed parts.

[@明天的太阳-l7t]

这是一个很棒的视频，可以有利于初学者的理解

[@jwd1776]

Can you do a video on printing threaded inserts? Thanks.

[@PattysLab]

Bigbrain video 👍

[@Derp3D]

3D engineering. Always have great ideas. Thank you 👍

[@slant3d]

Our pleasure!

[@GuilhermeGomes2]

Amazing content. Dont forget to mention the influence of the material as well: PLA for instance will change its tension over the placed part (or rod) with small time of stress.

[@calebkierum6871]

Ok question what does this mean? I think I am sort of getting the gist but is there a name for this effect or a video about it?

[@fluppir]

Man I had this exact problem today! Tell me do these reliefs apply to both side and top holes? I printed something flat to have the most strength but the rod crack the hole anyway. Thanks so much for all your advice!

[@JakeMcIvor]

The teardrop technique is typically only used for sideways holes, as it is to compensate for finite layer thickness of the slices.

[@slimdog72]

This was rad, thanks dude.

[@joelnederlof4227]

My wife is gonna leave me when she sees this title in my recently watched

[@georgecook8696]

Legit, keep em coming Slant

[@slant3d]

Always

[@_skyyskater]

that's sick and super useful. thanks!

[@Superskull85]

Would there be any reason to not use one of grip fins or crush fins? (reusable vs permanent w/ glue) Because those two feel like they would fit 99% of scenarios.

[@Superskull85]

Hmm nevermind. After going through comment discussions most polymers would seem to fail almost all of the solutions over time.

[@Stef-an]

Very useful video! thanks a lot!

[@lukasvonniederhausern6153]

Nice, thank you!

[@YPOC]

The hole at 5:37 seems ideal to insert threaded stuff of unknown shape into. Might be good if you have a fine thread that your printer's resolution can't match.

[@Graham_Wideman]

If you want to screw a small fine-pitch screw into plastic, you can just print the hole a little small, and the screw will form its own threads. This works fine for, m3 screws holding on lids, for example. Obviously not as strong as a threaded insert or captive nut, but good for some purposes. You can start by printing a test piece with several size holes in different orientations to see what hole size gives you the best effect.

[@hydroponikstuttgart4515]

hi, great video, it showed up at me feed exactly when i needed to design a universal pen holder! Modified the last approach to maximize flex of the hole diameter, only one large flexibel element instead of multiple. Works like a charm, cheers

[@philliptoone]

7:04 "Use this hole over and over again." 😂

[@Dallasrebar]

I stared at my part for an hour yesterday trying to figure out how to print a hole at the top of my model without using supports. I ended up just cutting the whole piece in half so there were no overhangs.

[@slant3d]

That is another way. you can also rotate the part so it prints diagnonally on a corner

[@masklessninja]

Holy polymer I was hoping for this topic!

[@slant3d]

Thanks for watching

[@johnecker]

That tear drop design is the symbol of the RepRap project for that design reason

[@3DThird]

These are exceptional tips for 3D printing 👍🏻

[@linuswalden]

Big fan of the quantity on this channel! :)

[@slant3d]

Thanks

[@bukszpryt_]

Grip fins won't hold with constant force for a long time when printed with pla, as it can deform under constant load.

[@slant3d]

Don't use pla. There are other plastics

[@modernmakes]

Great video! Thanks for this

[@zavarykinvisuals]

Very useful knowledge!

[@JohnSF93]

Great video! Though the shallow focus you had on your camera when showing the diferent prints made it very difficult to see the details :/

[@motoformprototyping]

Thanks again for these good vids

[@aware2action]

For the unsupported top hole, print it on a 45 degree belt printer😮. Any side holes should print well too. No need for any workarounds!😊❤👍

[@slant3d]

Or rotate the part 45 degrees and don't use a bed slinger

[@GoatZilla]

​@@slant3d u know most other kinematic types (minus the delta) still sling the bed. they just sling them vertically...

[@ziad_jkhan]

Very useful indeed...thanks a lot!

[@slant3d]

Glad it was helpful!

[@TheLaXandro]

I always had this issue of holes always being undersized if I don't make them oversized in the model itself. Very annoying.

[@lifeteen2]

Holes will always be slightly undersized because of the mesh approximation in STL files. There are other reasons too, but most sources of error in the slicing processes all tend to undersize holes. Until slicers become geometry aware there's not a universal solution, though I predict that's coming in the next few years.

[@gbdmager2719]

im not old enought to watch this vid with a straight face. but cool vid, even tho i dont have a 3d printing mashine, maybe in the future

[@ThatVideoGuyTom]

Brilliant. Thanks

[@burnout.c]

Very useful design tips !

[@slant3d]

Thank you! Cheers!

[@tomsko863]

You completely skipped over the most important detail: what brand are those tweezers!?!?

[@jacobcrowley8207]

Great holes.

[@JesseSchoch]

one note: buy a cheap set of reamers and then you can easily get perfect sized holes much easier to control than trying to use a twist drill on plastic.

[@EpicZombiez2314]

That thumbnail has me cracking up! My ADHD brain started reading "HASS" and immediately jumped to the giant "HOLES". The accompanying image just added to the experience lmao.

[@DomenicoMilone]

When i read "hassle-free holes" I didn't think about 3d printing. Very interesting though