What is the best way to attack a difficult 3D print? How do the Pros do it? In this WTFFF?! episode Tom and Tracy discuss tips and best practices to help you achieve success with Russell Singer of Make-It Inc.

With so many variables including temperature, speed, filament, complicated geometry, infill, wall thickness, support structures, and more, hours can quickly become days as you experiment with different settings. Russell takes us through his process that he uses every day to eliminate variables and achieve success in the shortest period of time.

LINKS MENTIONED:

• Make-It website
• Matter Control
• Cura
• Simplify 3D

Attacking a Difficult 3D Print

Where to start when attacking a difficult 3D Print? Russell Singer of Make-It asked if he could try printing our angel ornament on their machine. We agreed, and he has been trying it, and reporting back to us that it is challenging. He has been sending us pictures, and we have been going back and forth for almost a month on it.

Russell is the Director of Design and Development at Make-It, and part of his job is to help companies, usually customers who own their printers, dial in their print settings, figure out which are the best settings to start with, and adjust their settings to end up with what you want or what you expect.

We decided to interview Russell and ask some specific questions about how a professional attacks a difficult 3D print. With so many variables including temperature, speed, filament, complicated geometry, infill, wall thickness, support structures, and more, hours can quickly become days as you experiment with different settings. Russell takes us through his process that he uses every day to eliminate variables and achieve success in the shortest period of time.

LINKS MENTIONED:

• Make-It website
• Matter Control
• Cura
• Simplify 3D
• Horus Drones
• Russell’s Blog post – Backpack Clips
• Clip Files on Thingiverse

Questions for Russell:

T&T: So Russell, thank you so much for joining us today on WTFFF. We are really interested to talk with you on a little more technical subject than sometimes we do on our show. But we have a lot of listeners who are interested in those technical details.

We have been getting a lot of questions about attacking a difficult print. You have been attacking one for us right now, so we thought it would be a really good tie-in.

R: Yeah, it’s certainly a difficult print.

T&T: We are talking about our angel print.

R: Overall, it’s generally a game of educated guesses and trial-and-error. That really is the best way to describe it. When I start on something that I think is going to be a difficult print, I usually try to do it with a very specific filament that I know well and have had good results with in the past.

T&T: That is really smart. You try to remove all the variables.

R: Exactly. So I’ll usually use a white or natural filament. I will start with whatever temperature I absolutely know will be high enough, and I tend to start working down. I start at whatever speed is the absolute lowest I can tolerate waiting for it to print and start working up from there.

T&T: Let me ask you this. Why do you start at a higher temperature first?

R: To make sure that you’re getting good layer bonding and to make sure that you have proper flow everywhere. I start at a temperature that I know will work but not a maximum temperature, something that I am pretty certain is in a good range. Then I will start moving down because I find that the quality of the printouts you get is pretty much always better if you print at lower temperatures and you can have success that way. If you go too cool, you start to run into layer bonding issues, and so that is why you work backwards incrementally until you get to a result that has the quality and the strength that you need.

T&T: Then you start at the slowest speed, and then speed up as you can.

R: One of the things I like to do, which sounds very laborious if you don’t have the right set-up to do it, but on the machines that I use, I can actually adjust all of these things on the fly. So all of our temperatures, cooling settings, even material flow rates and speeds, I can adjust during the print. I will set something that is very conservative, and I’ll watch the first few layers and see how it goes. If it is speed, I will work in 5% increments or 10% increments sometimes if I think I can make a jump. If it’s temperatures, I will work in five degree increments. I will go until I start to see all of the results I need to see.

T&T: That’s really interesting. I hadn’t really thought about it. It’s a trial print anyway, so why wait for it to happen and crash it?

R: Even within one print, if you are doing it just to test and you have the ability to adjust settings on the fly, then you can go through all of those settings. You can go through a whole range of everything in just one print. You don’t end up wasting too much material. And if you have already set yourself up with the idea that this is just a test, you’re not going to worry if it’s going to turn out perfectly, and there is no real loss there.

T&T: How hard is it from a practical perspective to learn on the MAKEiT printer how to adjust those settings on the fly?

R: It’s actually quite simple. It’s just one turn of the dial on the on-board control menu that we have.

T&T: So not all printers work like that, we should mention. Not everybody will have the ability to make adjustments on the fly. But if you have a printer that you can, that would be great.

R: Right. But there are softwares that allow you to do it. I usually print from an SD card, which is why I use the on-board controls. I do that because I find it to be more reliable than the USB drivers on my computer. I get fewer failures that way.

T&T: You know, Russell, let me interject there. I agree with you; that has been my experience as well. On any printer that has a stand-alone operation with an SD card or a USB flash drive, I prefer to do it that way because I have had problems with my computer driving the printer over USB. I don’t know if that’s because of my computer or the printer, but it seems the USB connection for me has been a little less reliable.

R: Yeah, I always recommend, unless there is a very specific reason you need to use USB, I always recommend that you use the SD cards on the printer. But that is a little bit of a tangent.

T&T: Yeah, sorry. But it is important. If you are removing variables that might be affecting the difficulty of a print already, you want to remove all of the possible variables.

That is true. On a printer that I had, which was a European-manufactured printer that I was doing a lot of test printing on, I found that at times the extruder’s motion would stutter or even stop at times. I couldn’t understand that, and it turned out to be because of the speed of communication. Something about the USB was getting clogged up. When I went to print from an SD card, printing stand-alone, it eliminated that problem. I think it applies here because if you are trying to eliminate variables and get down to what are the right settings for the print, you don’t need problems like that.

R: Yeah, exactly.

T&T: Just to recap where we were: filament, temperature, and speed are the top three things you attack. Is there anything else, though, that might help a difficult print?

R: You have to always relate it back to the geometry, too. If you have a functional result in mind, your layer heights, for strength, you are probably going to use thicker layers, and you might not end up with as beautifully smooth of a part, but you will have something that is a little more robust. Tweaking your settings for strength, if you want functional components afterwards, that is pretty important.

A lot of times, I think wall thickness can really overcome infill settings. I have found that unless you have something that is very large, like a football size or something like that, you can get away with doing thick walls and lower infill settings and actually get pretty strong parts out of it that print quite a bit faster, I think.

T&T: That’s an interesting concept because a lot of people out there are saying, “With any infill can be super strong,” but you’re right. It will still crack on the outside, so what’s the point? But infill also takes a while to print. It does. So you can do anything to reduce the amount of infill.

You are saying in your experience, and it probably depends on the geometry of the part, that you can trade infill percentage for wall thickness. At certain times, that would make sense. This would give you some speed, too.

R: All of these settings, things like temperature and flow and speed, after working with a printer for a month or two months, you start to get an intuitive feel for these things. If you stick with it, you can get things pretty close to the settings you need 75%, 90% of the time on the first try.

But really, where I find difficulty still is doing support settings. For me, that is the most difficult thing because every part is very different. I actually have an example here. Can I turn the video on for a sec so I can show you guys what I am talking about?

T&T: Yeah, you can. Our listeners can’t see it, so we will have to post up a photo of it later.

R: This part is on Thingiverse, so you can link to it as well and people can download it. I have a side release clip or buckle.

T&T: That looks like a pretty common buckle people would have in their grocery store cart for the belt that goes around their toddler.

R: Yeah. I modeled this, and I can show you here, because the one that came on my hiking backpack broke, and I wanted to replace it. I have the replacement here. It’s been on there for three months now. It printed in PLA, and it’s held up.

T&T: That’s great.

R: I use it to carry groceries when I’m riding my bike, and it hasn’t failed yet.

T&T: That’s a really good example of a functional application for 3D printing. We get a lot of questions from people about what you can use 3D printing for. Because you can do almost anything, that really paralyzes people sometimes as to what to make. Here you are making a replacement part for your backpack because your backpack is perfectly good. Why not use it or why throw it away when you just have a plastic part that failed?

R: Exactly.

T&T: Why was that so difficult for support, though?

R: The clip was actually very easy; it didn’t really need a whole lot of support. But I wanted to make the pair with the buckle as well. The buckle, having a large internal cavity that has to have something that can smoothly slide in and out of it as well as crisply make that connection when the side release snaps, to be able to crisply make that connection when you slide the side release clip inside of it, you need to be able to really cleanly remove that support. It took quite a bit of time testing to be able to get the right kind of removable support in that enclosed cavity because I had support printing on the top surface of the lower part as well as supporting the upper surface above it. If you don’t get your support settings exactly perfect, you end up with some very rough surfaces, and then the clip won’t slide.

This is something I tried printing in all different materials. It turns out PLA has worked for a few months, and I tried it in ABS, polycarbonate, and nylon as well. For each of those materials, you have to have different support settings because they bond to each other differently.

T&T: More variables.

R: Exactly. Support, I think, if you can really master support, that’s great, but it is very difficult.

T&T: Tom, you typically make your own support. You don’t use any support settings on a lot of things.

It depends on the part and what the object is. In case of our 3D twist tie, I did make our own support because I really only needed it in a very small portion of the print, and I didn’t want to use a conventional support because I wanted it to break off really easily by hand when you get it out of the printer. It was a minimum amount of time cleaning it up afterwards.

We have a design criteria or mission. We try really hard to make it come off the machine and ready to go with as little handling as possible. The idea of removal of support, we just don’t want it to be complicated.

R: Yeah. That’s really important. One of the partners who we have been working with is Horace Drones, who I think the last time I spoke with you I mentioned them as well.

He has designed an arrow cover for his drone that needs to print with quite a large amount of support underneath because there is a big cavity there. It was really important for me to do a whole bunch of tests, probably seven or eight different tests on that one part, and it is a large part, so that took substantial time to make sure I could very easily take it off the machine and remove that support with basically no effort. We are looking at producing a lot of these parts.

T&T: And that time is money.

R: Exactly. That is also the reason why I tend to go for breakaway support over soluble support. There are a few occasions where I think soluble support is the right answer, but you end up waiting so long for it to wash away completely. If you can just grab the material, pull it away really quick, and have a nice, smooth surface, to me, that is way better.

T&T: We agree. We like the breakaway support as well. We have had good experience with it. Anybody that has a single extrusion machine has no choice but to do it that way. It would take a dual extrusion machine. Printing with two materials is not a novice game, either. You need to have a bit of experience before you get there, as we discovered somewhat the hard way.

These are really good tools and tips to try to attack a difficult print. Is there anything that, in your mind from having done a lot of these, defines a difficult print, besides needing support? Is there something that usually happens geometrically, or is there something that you look at and know it’s going to be difficult?

R: It’s not one specific geometry because even things like very, very fine threading, I’ve found producible. And very thin long pieces that are swoopy and have overhangs are producible.

But what is difficult is the variation in geometry. Somebody recently gave me a file they wanted tested where there was a very large volume that continued up for a couple centimeters and then all of a sudden tapered to a very small point that had threading on it where the threading was maybe metric five in comparison to the rest of the part, which was about five centimeters in diameter.

Making that switch between geometries: if you have something like the angel file, which I have been trying to print for you two, there have been some significant changes in geometry in that. You have the upper portion where you are numbering for the year. That is a very solid volume, and you have lettering that needs to appear there. Compared to the rest of the part, where you have very thin, delicate, are they lofted curves?

T&T: They are actually spiral helix-like sections. There is not a straight, flat surface on that entire object. Everything is constantly changing in maybe not thickness but in its position and geometry. There is a mathematical order to it, but it is also curving and flowing at the same time.

R: For something like that, being able to adjust settings mid-print is really important. You can actually do that with some of the free programs that are available to slice with. There is plugins for Cura if you use Cura.

I think MatterControl actually comes with a built-in ability to adjust temperatures at least.

If you are a Simplify3D user, you can all do kinds of stuff. You can adjust infill for different layers, temperatures, speeds for different layers. Having those abilities, you can look at very difficult print in parts and figure out how to chop it up and change your settings as it is going through to get the best result for those parts.

I make that sound easy talking about it, but it is something I am still learning right now. Simplify3D is so complex with so many options. I would recommend using some simpler programs and try to get a compromise of one setting before going to that.

T&T: It’s interesting to hear your perspective on those softwares. Personally when I started, one of the first open softwares I tried was Cura, and I found that hard to understand at first.

Simplify3D, while it is a very complex program and gives you a lot of capabilities, I actually find it not so hard to understand conceptually, I guess, as to what I want to do. The tools make sense as to what they do in the different processes for different regions of a print. That is what I prefer.

But what I like about this whole discussion and what it is communicating to our listeners is that when you get into FFF 3D printing, whether you are doing it for a small business or not, you really need to spend a lot of time on a technical level, trial and error, working through these prints, even if you are an expert. You work for a company that manufactures 3D printers, and it is a big part of your job, isn’t it?

R: Yeah, every day.

T&T: And that is what I think we want to express to our listeners out there. Don’t give up on your geometry so quick. It is technically difficult sometimes, and that may be what will make it a fabulous print in the end. Our angel is worth it when you print it; it looks great, but sometimes it takes up to 100 hours to dial in your technical. It did for us on this because it was one of our earliest prints, so we had a lot more to learn. But we don’t want people to give up so fast on their geometry and say, “Oh, my design’s bad.” Your design might not be bad; you just need to really work on the technical side of it.

R: That is something I always try to impart on people. Of course, it’s material science and engineering, 3D printing. But it is really not an exact science.

For anybody who is getting started, thinking about getting started, or even if you have had some bad experiences and are losing your patience, it is something that takes time. You have to really get a good feeling for both your machine and the materials you are using, as well as every specific part you’re doing because there is no end to the improvement you will see as you keep printing. Like anything else, you just gotta stick with it.

T&T: Those are very informed, wise words there. Russell, thank you so much for spending some time with us today discussing this issue. I think it probably isn’t understood enough, especially for newer people getting into this industry, that there is a time commitment required, there is a lot of skills you have to build over time, and a lot of comfort level with your machine and the geometry of your prints.

R: Exactly.

T&T: Thanks very much, and we would like to reach out to you again in the future if you don’t mind, perhaps when certain other technical questions come up. I think you would be a great person to help out with those. Would that be all right?

R: Absolutely. I’d love to help out. Any time.

***

I’m so glad we had this episode. I mean you know it’s technical, and of course it’s Christmas Eve for those who celebrate, so it’s probably the weirdest topic to be offering up tonight. But some of you may be getting a printer tomorrow, or you got it for Hanukkah, and you’re just starting to print. I’m the non-technical person here, and I think it’s really important for everyone to understand if you are just starting to 3D print. This is where a lot of frustration happens.

I agree with you actually. I had a Skype call a couple days ago with a listener of ours who had just bought himself a MakerGear M2 printer. His name is Tom Fassell; I think we have talked about him once before on the podcast. But he is struggling with some of these same things. He is a very new user and really is just getting a crash course education. It is highly technical, and how do you go about printing certain things?

I think especially because a lot of our listeners are learning to 3D design at the same time as they are learning to 3D print, I think some people are too quick to give up on their geometry.

That is what was really interesting about what Russell was saying: that even if it is difficult geometry, if you know it looks good and you don’t have holes in it, too thin of areas, or obvious flaws in your geometry, then don’t give up on it because there should be a way to print it.

And there are people out there at most of these printer companies like Russell, or there should be if there aren’t, to help you do that because they want you to be successful.

I know that there are. It is in their best interest to make sure their customers are happy and do achieve success with their prints. Russell is doing that at Make-It. I know Airwolf 3D has a person who does that as well. We have used him before.

I think that is really a side of things that you really want to make sure that you really understand it takes time. And that is why when some of these people are asking us to print their angel, we know it’s not going to be easy. When they are saying, “I have this design, and I want to create it this way, and I need it for a birthday that is in two days,” it’s not going to happen. It’s not because 3D printing is so hard, but rather because there is a big learning curve here, and that is what our podcast is all about. It’s all about scaling that learning curve as fast a time as possible.

But there are so many aspects you have to learn. You have to learn about temperature, speed, geometry, and support. These are all complex topics. As he pointed out, it’s not an exact science; we like to say it’s an art. That’s how we feel about it: it’s an art, and there is a lot of science to it. There is a lot of invention that is going on here. This is uncharted territory here. I feel that there is a really good way to make it work. That is really the point of it. You can make it work if you really want this design to come out of the machine. I agree. You can.

But one thing I was thinking as we went through this interview that I want to point out to our listeners is that if you are looking at integrating 3D printing into your business or building a business around 3D printing, I think this really points out how important it is to have a dedicated technician or to build that into your business plan at some point in time. Maybe it’s not immediately, maybe it’s down the road. And you need to leave yourself time for that.

This is one of the things that we are working on right now. We are developing a product line for a client, and it’s a 3D print product line. We have to not only plan enough time to get the designs, but we also have to plan enough time to technically dial in the print of it so it prints as efficiently as possible and as quickly as possible because that is money as well, so we can get and hit the target price points.

All of those things from a business perspective have to be designed in, and that is the iterative design process that we always talk about: You design it, get what you ideally want, try it on the printer, and dial it in until you get it right, and maybe you have to go back and redesign some things.

While I agree that it is critical for people who are designing parts and products to be 3D printed to have 3D printing experience and understand it very well themselves, I also think, because we are looking at doing this for our business in 2016 and expanding it and doing more design for 3D-printed products, we are building into that plan having technical people on our staff that are not designers.

We don’t want designers all day long messing with the machine. We want every designer to use the machine and understand our machine, but we don’t want them to become technicians in the end because someone who has competency in getting the right temperatures and the right speeds and all of those things should do it because they have the expertise there. They are going to be more focused in that area. You are more focused in design, which is critical as well. They are all related, but wow.

That was really great. I enjoyed that interview.

Just don’t give up. Maybe your upcoming New Year’s Resolution is to learn to 3D print. Plan yourself enough time. Realize that the design process is one part of it, but the technical process is a requirement and needs its own time. Agreed. And it’s a wonderful thing. If you get bitten by this bug, love it, and want to do it, like you said, it will take time. But you will get there if you can commit the time or if you have other resources to help you. Take advantage of those resources that are available to you.