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3D Printer Comparison: $200,000 vs. $2500

additivepartdesign.com

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Re: 3D Printer Comparison: $200,000 vs. $2500

#91

Post by TD-Linux »

rfrey wrote: post #67
ahoka wrote: post #38

Earlier quoted context omitted.

"It sums to "I can tweak my setup and get this part to be good enough relative to the expensive machine." and that is great. What is missing is it is every friggin' part. Seriously, all of the $2,000 printers have quirks that hit based on part geometry, especially in ABS. Part too long? need to add hold down tabs to prevent warping. Too many overhangs? extra supports. Too long a tool travel? Up the hotend temperature…

No, this is like the crusty machinist who knows just how to wiggle his hips and shake his elbow to get a 1/2 thou on the worn-out bridgeport in the corner. FDM should let engineers make prototypes without bothering that guy (whose time is probably 3x more valuable than theirs, even if his pay doesn't reflect it). This sounds like the printer is just a more compact version of the worn-out mill. Plus you have to accoun…

The RepRap project and the derived printers tend to share the opposite philosophy - the original idea was to print parts for more printers, so naturally parts were designed to be 3D printed. The RepRap logo is a compromise design for part holes without support (no longer necessary, though).

Most RepRap owners ('hobbyists') are using the 3D printer as the end manufacturing method, not just for prototypes, so this is a pretty reasonable tradeoff. Note that the original article fell into this category - the 3D printed part was not a prototype, but a jig used in production. (looking at that part, it could have been designed to not require any support material at all)

Re: 3D Printer Comparison: $200,000 vs. $2500

#92

Post by TD-Linux »

onion2k wrote: post #12
huuu wrote: post #2

If his conclusion were true companies like Shapeways would only use cheap hobby printers. But ofcourse it is not. Reliability, support, accuracy, all lacking with hobby printers.

If his conclusion were true companies like Shapeways would only use cheap hobby printers. But ofcourse it is not. It's far from a perfect analogy, but with servers Google demonstrated really well that the cost of high-end 'professional' equipment can be a waste of money where cheap, commodity kit can be used at scale instead. It's not completely unreasonable to think that a farm of cheap 3D printers could be used in…

In fact, the $2000 Lulzbot printer used in the article is made of lots of 3D printed parts, manufactured on a farm of Lulzbot printers: https://www.youtube.com/watch?v=v_jUObUGLTA

Re: 3D Printer Comparison: $200,000 vs. $2500

#93

Post by baq »

TeMPOraL wrote: post #64
baq wrote: post #14

Earlier quoted context omitted.

i haven't ever used or owned a 3d printer and this part >This quote, "With some tweaks to my G code and use of a nozzle that is more suited for higher resolution prints I am confident that I could produce a part that would be very close to the quality of the Stratasys produced part." really summed it up. It sums to "I can tweak my setup and get this part to be good enough relative to the expensive machine." and that…

Sounds like your job involves making small amount of similar text manipulations on a large number of computers. Which is different than what the tools you mentioned were design for - i.e. for doing lots of different jobs on a small number of computers. As a dev, I use two computers +/- a few shells for most of my work. Little enough to manage configurations by hand. I'm more like a machine shop from GP's comment - ma…

actually it's not that bad - i've got 3 boxen that i use regularly and that's it. the problem is that those machines get EOLed every once in a while (say, 2-3 years) and each time i get a replacement i dread about some config setting that i set to solve a problem or whatever and then forget about it. it's a problem that happens often enough to be annoying but also seldom enough to not be worth automating, because software evolves, etc. i've got a few most important dotfiles on dropbox.

Re: 3D Printer Comparison: $200,000 vs. $2500

#94

Post by Animats »

patcheudor wrote: post #61
Animats wrote: post #5

From the article: "One defect I observed on the Lulzbot printed part was the blade portion of the tool had a split in it from not bonding correctly. This was most likely a cause of pushing the 0.5mm nozzle to its limits in terms of layer height but a little glue and some pressure would fix this split no problem." Er, that's called a "reject" in manufacturing. This is the basic problem with low-end filament-type 3D pr…

"This is the basic problem with low-end filament-type 3D printers - weak layer bonding. You're welding a hot thing to a cold thing, which never works well." Bonding always works well for me and many others. The author of this story choose to use a material (HIPS) which really should still be considered experimental for most FDM printers. I've personally never had a lot of luck with it and instead choose to use either…

Thin is the good case. It's thick parts that have problems. At TechShop, things seem to crack around 2cm-3cm thickness.

Re: 3D Printer Comparison: $200,000 vs. $2500

#95

Post by dekhn »

I see cheap 3D printers like I saw linux in 1995: not quite the functional equivalent of a $100K SGI workstation, but still a great way to get experience in the area. You just have to understand that much of your time will be spent tuning the printer, and fixing it, and upgrading it. I don't know that the Statasys fails nearly as often as a cheap printer.

Re: 3D Printer Comparison: $200,000 vs. $2500

#96

Post by dekhn »

deskamess wrote: post #65
jacquesm wrote: post #29

Earlier quoted context omitted.

> Are there any 3D printers that integrate a milling machine? No, and there likely never will be. Why would you wait for hours to then still have to mill down your final product when all the advantages of 3D printing are then lost and all the advantages of milling are lost? The advantages of 3D printing are that as an additive process it will work in many environments where a subtractive process would not, the advant…

Wow... I have never thought of the process in the linguistic terms "additive" and "subtractive". That actually changes the mental model for me. I have always thought, in less abstract terms, about removing shapes (carving out) and optionally sticking external parts (bolting on) to get the desired product. The specific add and subtract "language" presents it in familiar, abstract, and, more importantly, composable mod…

See 'constructive solid geometry'.

Re: 3D Printer Comparison: $200,000 vs. $2500

#97

Post by dekhn »

willvarfar wrote: post #22

I have never seen a 3D printer, although I have seen a model (of a house plan) made with a 3D printer. You folks who live near civilization and 'make' communities are so lucky! :) Are there any 3D printers that integrate a milling machine? I imagine a machine that prints the model slightly oversize, milling and then perhaps finally warming the surface to polish it, all as it goes... I would love to have access to a h…

There are combo machines but they are almost always worse than having two machines, and then moving the part from one device tothe other. Then, machining is an issue- your CAM/slicer need to work together.

Re: 3D Printer Comparison: $200,000 vs. $2500

#98

Post by dekhn »

Be aware that the high end printers include features that are patented, for example soluble support, heated build chambers, etc, all have IP around them that may prevent companies selling inexpensive printers from including those features directly. This could translate to better results from the high end printers.

Re: 3D Printer Comparison: $200,000 vs. $2500

#99

Post by patcheudor »

Animats wrote: post #94
patcheudor wrote: post #61

Earlier quoted context omitted.

"This is the basic problem with low-end filament-type 3D printers - weak layer bonding. You're welding a hot thing to a cold thing, which never works well." Bonding always works well for me and many others. The author of this story choose to use a material (HIPS) which really should still be considered experimental for most FDM printers. I've personally never had a lot of luck with it and instead choose to use either…

Thin is the good case. It's thick parts that have problems. At TechShop, things seem to crack around 2cm-3cm thickness.

I routinely do thick 100% fill parts in ABS with no issues.

Re: 3D Printer Comparison: $200,000 vs. $2500

#100

Post by MikeAPD »

kragen wrote: post #89
MikeAPD wrote: post #72

Hi, I wrote the article. I am really enjoying the comments everyone has contributed. One major detail I left out was the amount of failed parts that came out of the professional machine prior to getting a good one. I was unaware of the reject rate at the time I wrote this. In addition, the production tool ended up having resin added and then sanded to cover up some of the imperfections on the "professional" print.

What was the reject rate? Also, some of us have asked some other questions about tolerances and material properties in other comments on here; could you answer them? I'm sorry about the somewhat intemperate comments of some of the other commenters.

I can't give you an exact reject rate but it went through at least 3 iterations before being acceptable. As for tolerances and material properties (overall strength of the part) the Stratasys machine is superior in both aspects. As I mentioned in the conclusion of the article, I would like to do more experiments on the parts including dimensional analysis and possibly a tensile or compression test. Having 1 data point (1 tool from each machine) wouldn't be the best results for an accurate comparison but I would still be interested in the results.
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