Wall Hook Update: ABS Print

I was a little worried to print my wall hook in ABS because I read plenty of posts from makers that said that it tends to warp and split during printing.  Since I already had a spool of ABS, I figured I should give it a try.

The print came out looking great.  The ABS print actually has less visible layer lines in some spots.  That might be because I used a white ABS filament compared to a matte light gray PLA filament.  

I only had one issue with this project.  When I was setting up the project in Cura, the recommended bed temperature for ABS is 80 degrees Celcius.  My printer gave me a couple messages that stated, "Heating Error, Printing Halted, Please Reset.".  I am not sure was caused it, but I will say my printer does that when I run the bed hotter.  So I consulted the specs for ABS and saw that 80 degrees were on the high end of the range.  I tried the print with bed temperatures of 70 and 75 degrees.  In the end, 75 degrees worked out well.

As I write this, I have the printer heating up to run a different project in ABS.  I will have to see if I get similar results.

ABS Hook Installed

Wall Hook In Use

 

3D Printing a Generative Design Model

In a previous blog post, I talked about design a wall hook for my backpack using Generative Design in Fusion 360.  The goal was to then get the design 3D printed.  Now that I have a 3D printer I am able to print this design.  I purchased a Creality CR-10 S5 and this was one model that I used to learn all I needed to know about how to get good 3D prints.

Creality has its own slicer, but I have read that a lot of Creality owners use Cura, which is Ultimaker's slicer and free.  I wasn't sure which one would be best, so I bounced back and forth between the two for a while.  I have since settled on Cura because it gives more options than Creality's slicer.

Cura will take in an STL file that I can export out of Fusion 360.  There are two ways to get the STL file out of Fusion 360.  I can either use Export or 3D Print to accomplish this.  If I use 3D Print, I can send it directly to a 3D Print Utility, I tried this once, but I don't get to save the STL to my chosen location or even name the STL.  So I just save it to a file then load it into Cura myself.  I have also learned that it is best to switch your document units to mm before using the 3D print command.

Export Dialog

3D Print Dialog

Once the STL file is exported, it is just a matter of opening Cura and inserting the STL into a project.  I have used a few slicing programs over the years and they are all pretty simple to learn how to use.  You just need to position the model on the build plate where you want it.  In my case, I had to rotate it so it laid flat on the build plate, which will minimize the number of supports it would need to build.

The first time I printed this model, I realized that it is way too small.  I do have a little bit of an issue with picturing my CAD designs at full scale.  So the second time I ran this, I used the slicer to scale the model 2x, which in retrospect seems a little too big.  I know this wasn't the proper technique.  I just wanted to quickly try it at a larger scale.  The main reason this is an issue is that the holes are twice as large.  I am okay with the scale of the rest of the model, I might have to use washers when I go to actually put this part into use.

When I was going through the Generative Design study, I chose ABS as the material for this part.  That was solely based on ABS being in the material library and PLA was not.  When I bought my printer I bought a spool of ABS and a couple spools of PLA.  The versions of this above were printed in PLA.  The larger one feels sturdy enough to use.  I used PLA to print this for two reasons.  First of all, it was already in the printer.  Secondly, now that I have a printer I have read that ABS is harder to print.  I was curious about which material is considered better, so I did a little research.  I discovered that PLA is actually stronger but more brittle.  ABS is more heat resistant, which requires higher bed nozzle temperatures.  It is very prone to warping.  

After read about the pros and cons of each, I feel that PLA is better for this design.  However, I do have a spool of ABS and I think it will be worth trying to print this in ABS just to see how it comes out.   

Here is a video tutorial that shows the process.

My First Month with a 3D Printer

I have been wanting a 3D printer for a number of years now but wasn't sure how much use I would get out of it, so it remained a "wish list" item.  Then recently, we realized that it could be used to make 3D stencils for my wife's furniture refinishing business. Initially, I was looking at smaller printers, but since my wife wanted to make decent-sized stencils, we needed a larger printer. I started looking for affordable printers, with a larger printable area, and good reviews.

After several months of research, I landed on the Creality CR-10 S5.  It has a 500 mm x 500 mm x 500 mm build area.  It was within our budget and had many good reviews on Amazon and YouTube.  So I ordered it and it took about two weeks to arrive because the printer was out of stock when I went to order it.

I was very excited the day it arrived. I knew it would take a week or two to learn all the intricacies of the printer and get it tuned for easy use. That was a little bit of an understatement. It only took about 15 minutes to assemble and get working. However, it took a bit of time for me to figure it out. There are plenty of places to learn about how to 3D print, but I was confident in this being an easy machine to use that I didn't bother watching those videos and just jumped right in. It took me about a day to get a completed good print.

My first issue was bed leveling.  The first problem is that I didn't bother leveling it properly.  I was too excited to print and I didn't quite understand the process, so I half-heartedly leveled the bed.  Once I learned how to do it properly, I developed a pretty good system and now  I check my bed for levelness several times a week.  I have seen several users highly recommend the BLTouch auto-bed leveling system.  I am a little intimidated by the process of installing that, so I am holding off at the moment.  I feel that I have a pretty good system and have the bed in a good situation.  I can say that the table I had the printer on originally was not a good table.  It was older and I think I was fighting bed levelness issues because the table was not truly level itself.  I switched to a different table and my bed leveling issues were not as bad.

Bed adhesion was also a problem right away.  This printer came with a tempered glass bed.  I thought that was great because I have read about people costly have to change build plates.  My mistake here was that I thought that the glass was designed for the filament to stick to automatically.  After just a few minutes of research, I discovered that I was wrong.  You need to do something to the bed to help the filament stick.  I chose glue sticks, mostly because we already had that in the house.  Those have worked more often than not.  I have had a few projects that still don't stick well in the corners.  However, this printer has a large print area and I am not sure if the outer corners are getting hot enough.  I have read about people using hair spray, so I tried that and it didn't work as well as the glue sticks.  I also tried covering the bed with masking tape.  That didn't work well for me.  So I think I will stick with the glue sticks.

One issue that I feel I finally have resolved is the issue of the proper bed to nozzle distance.  It also plays a part in my bed adhesion issues.  I was following the advice I have seen online of sliding a piece of paper under the nozzle and when it slides freely then I have proper spacing.  I was still having some slight adhesion issues after doing that.  What I tried this past week that seemed to make a difference is that I would still use the piece of paper.  However, I adjusted the bed to the point where I could feel the paper catching a little.  Also, I could see the nozzle scar the paper just a little.  I had done that in the past and the nozzle was so close to the bed that my first layer was not the right thickness.  So to compensate, I just used the settings in the printer to then move the nozzle up 0.1 mm.  Since my layer height was 0.2 mm, it is essentially a half step.  This has helped immensely.  In previous prints, I would find that the first layer was inconsistent, some spots would be the full layer height, and others spots would be only a partial thickness.  My last two prints had a very consistent first layer.

I know that this sounds as if this has been a challenging month, and in ways it was.  My emotional state would fluctuate from ecstatic that my prints were going well to feeling like I made a mistake buying a printer.  Sometimes that was during the same print.  I really have enjoyed having the printer and feel like I have learned a lot.  If you are going to buy, or have just bought your first printer, hopefully, you can learn from my mistakes.  

I can also say, that I have learned that fine-tuning your printer can be as unique as people's taste in food or music.  What works great for me may not work well for you.  I tried to find optimal settings for bed and nozzle temperatures.  As I tried to replicate those, I found that I have had to run mine a little hotter than some recommended settings.  Maybe as I get more confident, I will start adjusting those down.  I have already started to tweak my normal bed temperature down because I was trying to compensate for bed leveling and adhesion issues.

I do plan on sharing some more lessons I learn as I go about doing more 3D printing, but for now, here are some pictures of my failures and successes.

3D Stencil

Church Window Decor

Wall hook that I printed with a bad extrusion feed rate setting

An example of my bed adhesion issues

My first successful print, the obligatory 3D Benchy