RC-modeler

After the new "Lost in Space" series came out, I guess that I started having fond memory's of my child hood and decided to go create a toy I never had back then. If you are looking at the photo and wondering, yes, it is floating in mid air. The magnetic levitation system does work nicely. Unfortunately this all the higher it can fly, so making orbit is going to be a bit tricky. The model is 8" in diameter, made on my Ultimaker II+ using Matter Hacker build silver PLA and IC3D natural PLA. I built the CAD model using an old version of Pro-E. When I first started this project I was amazed that there is not a single correct geometry for the original Jupiter II. My model is based on the special effects models that had compound curvature on the main part of the upper hull, making it look like a part of a sphere. The full scale set model, however, had straight sided walls, as though it were part of a cone. I guess that the set model was just plywood wrapped around forms and the compound curvature was just to much. I have debated on painting the model to hide the seams and the printing artifacts. It is puttied, sanded smooth and polished. The putty I came up with is kind of interesting. I used 15 minute epoxy with milled fiber added and some silver paint. I worried if the paint would actual dry encased in the epoxy, but it did. After sanding the entire assembled model and polishing it the seams look acceptable, sort of like a full scale manufacturing seam, not that there was such a thing visible on the TV show. Fun blast from the past. Steven

Recently used some Maker Geek Raptor PLA. It is a higher temp PLA that has better structural and temp capability. Printed very clean, for large flat top surfaces made the best finish I have seen yet. Prints on painters tape cleaned with acetone at room temp, and holds on too well, a little hard to get off. I have also had good experience with IC3D PLA. Prints straight to clean heated glass bed with out any trouble, no rafts or brims. Both of these are USA products.

That looks like the answer. Thanks, Steven

Good point. This is a test part to better show the problem than the real part. The islands that I refer to are in the larger circle, triangle and square, and you can also see the small bars. The small circles are just there to force more travels. Looking at the first layer you can barely see that at the end of the skirt the travel line to the main part is a lighter blue, it would appear that this means travel with retraction. All the remaining travel lines are dark blue, which seems to mean travel without retraction. In the photos as they appear here, the dark blue looks more like a dark gray. Going to layer 6 you can see that all the travel lines are dark blue, no retraction. Also note that no travels ever cross into an open area, they go to and leave the islands on the bars. Now going to layer 7, the first layer without the bars. Now the travels to and from the islands are the lighter blue, which seems to indicate we have retraction (when it prints I can hear the retraction happening, and this is where it occurs while printing), but the remaining travels are still dark blue. The remaining layers are the same. So it looks like Cura will only do a retraction if forced to cross an open area. All this leaves a lot of strings which detract from the appearance of the print. So how is this fixed? Steven

It would appear that I have been having this issue for over a year with multiple versions of Cura. The part I am printing is a name plate. It is 2mm thick with the name cut through it. It is bonded to another part that you can see through the letters that provides a contrasting color for the lettering. For letters like o, b, d that have an island in them I add a small bar across the letter to tie the island back to the main part that is 1mm thick. When I print this the skirt prints, I can hear the retraction, it moves over to the main part, with no strings, and starts printing, and there will not be another retraction until layer 6, and I get strings pulled all over the place, which detracts from the appearance of the print. What is unique about layer 6 is that it is the first layer that no longer has that little bar in it. But retraction only occurs when moving between the islands, and from the main part to and from the islands. The rest of the part still has strings pulled all over it. On layers 1 to 5 the print looks like one part, but layers 6 and up look like multiple parts. It would appear that Cura will only retract if it is moving from one part to another, or between isolated areas. Looking at the part in Cura layer by layer you can see that this is how it intended to do the job. Any thoughts on how to correct this? Steven

I have been having similar issues. I have been running Cura on my Windows 7 64-bit Laptop that I do my design work on. Shortly after upgrading to Cura 2.7, when I launched Cura I would get a message to the effect “Cura has stop running” and then Windows would offer to close the window. I reloaded Cura 2.7 and it work for a day or so. I then loaded Cura 3.0.3, and it would never start on the Laptop. I then loaded Cura 3.0.3 on our Windows 10 Desktop where it seems to be working. I am not sure but I think the problem started after a Microsoft Windows update. UPDATE: Reloaded 3.0.3 last night on my laptop, I was going to try a fix pointed out in one of the above mentioned threads, but this time it worked with out doing anything.

Yep a typo, I am running at 260 C, which is as high as my UM2+ can go. Folks that are having success with GD PC seem to be running 270 - 300 C I'll give glue stick another try and see if I can get the first layer to adhere. There were a couple of time I put it on while the bed was still warm, so that might have lead to some of the problems.

Hello, The part above is my first more or less successful print with polycarbonate. This is part of a Yeti mug cap for a friend. While the part is useable, it just barely made it. This is printed from Gizmo Dork PC, on my UM2+. On the first couple of attempts I tried using glue stick on the glass with no success; I would normally abort the print after 15 seconds. I then went to ABS juice, which seems to hold onto the PC pretty good. The first attempt with juice did not have a brim and about half way through it was warping so bad that I again aborted the print. On the print shown here I added a brim. The part is 2mm thick, so 10 layers, and during the 9th layer I felt pretty confident that this was going to turn out great, it appeared to be held down perfectly. But during the 10th (last) layer I could see that the edge was starting to lift and taking the inner half of the brim with it. As the print finished the outer edge of the brim was still attached to the glass. A few minutes later as the machine cooled down the part warped enough to lift the brim up all the way around. The failure occurs in the bond between the ABS juice and the glass, as the PC and ABS appear to be fused together nicely. So are there any good tricks to get the ABS juice to stick to the glass better? I have thought of trying Kapton tape on the glass, but from what I have read it sounds like the tape will be lifted off the glass. Does anyone know if the commercial products like Wolfbite hold to the glass better? Print settings – 260 deg C extruder, 110 deg C bed, 0.4 mm nozzle, 0.2 mm layers, 30 mm/sec speed.

Note to Moderator: I tried to post this several days ago but it has not shown up, hopefully this is not a duplicate. Please feel free to remove this line. Hello, this is my first post on this forum. I have been working with 3D printing for 2 years now, using my Ultimaker 2. The above photo (which I hope shows up) covers my main interest, which as my user name shows is R/C modeling. This part gave me an interesting problem that I would like to share. The parts shown are part of an R/C model fuselage. The top two have an under extrusion problem, the bottom one is where I fixed it. This is the second time I am making this model, the first time was around the first of the year after I finished the design. At that time I planned on sanding, priming and painting the parts after they were assembled, so I thought “print it fast and sand out the ridges”. So it was printed with 0.2mm layers at 60mm/sec with a 0.4mm nozzle, or 4.8 cubic mm/sec. Well, after sanding for a while I decided that PLA was not as easy to sand as I would like, so when I started the second one I decided to go higher res. This time around I went with 0.1mm layers at 50mm/sec still with the 0.4mm nozzle, or 2 cubic mm/sec. The first part printed very nicely, which is the nose section that attaches to part shown above. When I printed this part I was getting significant under extrusion. If you look closely at the middle one you can see places where both the inner and outer wall failed and you can look through it. I cleaned everything including the nozzle, moved the part closer to the front right corner to relax the bend in the Bowden tube and tried again, and got the same results. While the second attempt was printing I was feeling the feed of the filament to make sure it was really moving and realized that it was moving really slow, so I began to wonder if I was going too slow. For the third attempt I reset the speed to 80mm/sec. This time it printed just fine. An interesting thing to note is that the section ahead of this is completely closed as you go around the perimeter, on this part the print was good on the front section of all the parts where the perimeter is closed. The problem only shows up after it gets to the point where there is an open side. I have a couple of thought on what is happening. There is not enough pressure in the nozzle to survive the jumps. The plastic is spending too much time melted in the nozzle, and some material changes are happening that can’t be quickly pushed out. You can also see that the first 2 attempts have more stringing and in some cases that lines up with the larger flaws, which makes me wonder if the nozzle was dumping out and could not refill fast enough and for some reason moving faster helped. All in all somewhat unusual in that the fix was backwards of the normal wisdom of slow down to fix printing problems. Printing faster did reduce the X-Y smoothness very slightly, but resulted in a usable part. Steven