3-D Printing

[pixelplucker]

All the slicing software out there is finicky. I usually use obj format if the printer can take it simply because obj supports multi mesh models whereas stl only supports single mesh models. More and more slicing software can parse the multi meshes and combine the objects on a slice level with fewer errors.

Robcat has made some really nice models that parsed pretty well when we were making the medallions. Think there was only one error where Thom's shorts turned into a onesie but that was easy to fix :)

[fae_alba]

I haven't had too much of an issue with multi-mesh models. The canon carriage that I did a while bit was actually multi individual models laid one over the other. I just had to make sure that there was a bit of overlap to the mesh or it would just fall apart. I will say that 3D printing is not straight forward nor easy. There is a lot of thought process that goes into it, and each 3D printer has different capabilities and mannerisms. But it is fun, and it is rewarding to see a model created in A:M or any other application printed so you can hold it.

[Fuchur]

i printed it out again with supports enabled and a size of about 7 cm x 3.5 cm x 6.5 cm. It already looks promising. printed with 300 micron layerheight in black pla on my replicator 2.

not perfekt but pretty ok already.

As you can see we have supports at the front at the nose and the mask. i'll break them away and see how it behaves.

best regards

*Fuchur*

 

[Fuchur]

...and from the bottom. There are a couple of additional support below the legs. But those are not extremly needed if you ask me.

 

[Fuchur]

And here we go. It worked pretty well but i would need to work some more on the support break aways. It is sometimes (nose, etc) pretty unproblematic, but especially the once at the feet and at the mask are a little nasty. Still it is already working pretty well. :).

best regards

*Fuchur*

 

 

[pixelplucker]

Toss me an obj of that file and let me see if I can fix it.

[Fuchur]

i think there is not too much to do here anymore... At least my makerware(slicing software of makerbot) can handle the stuff now. the object already prints pretty much as expected. The next step would be to print it at a higher resolution like 100 micron in a little bigger and if wanted get rid of the overhangs a little more. (this is all fdm of cause. I think u've got an SLA machine or even a powder based one if you can print metal right?)

[pixelplucker]

SLA so I use supports to take care of overhangs. Takes a little learning and orientation is very model dependent. I had looked into an FDM to make fixtures and gadget but think a dual extruder be good for dissolvable supports. Wish I had an sls that could do metal but way out of my league.

[robcat2075]

16 hours ago, Fuchur said:

(this is all fdm of cause. I think u've got an SLA machine or even a powder based one if you can print metal right?) 

For our contest medals Ken is using the 3D print to create a mold in clay, then pouring molten metal into the negative space.

[Fuchur]

13 hours ago, pixelplucker said:

SLA so I use supports to take care of overhangs. Takes a little learning and orientation is very model dependent. I had looked into an FDM to make fixtures and gadget but think a dual extruder be good for dissolvable supports. Wish I had an sls that could do metal but way out of my league.

Dual extruders are nice (my replicator 2x is one) but as interesting as dissolvable supports are, they only have advantages if you are not able to reach the supports (for instance they are inside of an object or they are very small. The problem with supports for FDM is, that both are melting and get mixed a little. And like that they are not totally separated and will leave small marks too.

I would have to try it out again because the last time I did that is years ago (some software updates could make a difference here) but my first tries can be seen here:
https://www.patchwork3d.de/blog-5-en/abs-u-pva-print-on-my-makerbot-replicator-2x-514

I tried to make my replicator 2x a all-rounder-machine (it is in general meant to print ABS, not like my replicator 2 PLA) and ABS has a lot of problems with shrinking. But for PLA (which has close to no shrinking problems) you need different cooling mechanisms. For that I have build additional cooling fans next to my nossle and stuff like that but I never got it perfectly to run till now (have to admit that I did not try it extensively...) so I use my replicator 2 for most prints just because it is very, very dependable. I can shut it off for half a year, come back to it then and it will print as if it was half an hour later... I really like it.

The moment I activate my replicator 2x and print something else then ABS with it, I have to invest a lot of time.

That is, why I tend to just model stuff the way I need it to avoid overhangs... like these minions for a wedding cake:
https://www.patchwork3d.de/blog-5-en/minion-mariage-or-what-you-should-put-on-a-cake-part-1-731
https://www.patchwork3d.de/blog-5-en/minion-mariage-or-what-you-should-put-on-a-cake-part-2-732
(when I printed them I was in the middle of reassembling my printer with a new nozzle/print head so the quality suffered a bit because it was not really done till then, but it had to be done very fast because the wedding was close and it was still fun to do and they liked it a lot )

In the images attached you can see how I've split up the male minion model for printing it and then I just glued those together afterwards and painted them (and yes, I am really not talented with painting models as you may see )

Best regards
*Fuchur*

[Fuchur]

Oh and I just want to say sorry to you Pitcher, because I am really pretty much high jacking your thread here that much... maybe we should open another one for that?

Best regards
*Fuchur*

[Fuchur]

12 hours ago, robcat2075 said:

For our contest medals Ken is using the 3D print to create a mold in clay, then pouring molten metal into the negative space.

Ah, that explains it :). SLS/powderbased printers are really very expensive... even the one developed by Form Labs at the moment is pretty much out of my league... and that one is very inexpensive in comparision.

Just to have said it again: The quality of the molten medal is pretty amazing :). Thanks for the hard work on that it really shines happily on a prominent spot here :).

Best regards
*Fuchur*

[pixelplucker]

Formlabs SLS simply uses the new high powered violet laser diodes commonly found on the inexpensive cnc/laser marking machines. Their SLA is limited to just nylon.

I have a Formlabs Form1+ though It is a nice machine Formlabs as a company is not a reliable business partner because they build in obsolescence on their equipment and try to force people to upgrade. If you looking for a solid SLA printer check out the Peopoly MOAI. You can put your own together for $1300 USD. They use a slightly simpler design with the laser to galvo unit aiming directly up to the resin vat rather than adding another large mirror. Machine is just a little taller to compensate for the focal length.

As far as supports on the FDM that is interesting and I never thought of the different expansion of dissolvable and abs. In that case does it make sense to print supports manually added similar to ones uses in SLA and DLP printers? If that works then that makes shopping for an FDM much cheaper hehe.

Good SLS can fuse metal directly without the need for a polymer carrier that needs to be fired off. This makes dimensional accuracy better since there is little or no shrinkage. Those machines are in the $250k mark and higher. 

[Pitcher]

I didn't notice that there was a page 2 on this thread until tonight. I thought people had gone on to something else. The discussion on page 2 has been interesting, too. Fuchur, I am glad to see anything you have to say. You are not hijacking anything. It's all about 3-D printing, and I have everything to learn. The pictures of the print you made are really fun to see. I printed at the library, and it turned out pretty well, in general, but I have revised the model a little more, and I have requested that it be printed again about twice or three times as large, because some of the details were too small to see.  The model I have now is about 2 1/2" long.  I will try to take a picture the next time around. The model I am having printed is attached. I cleaned up some of the patches that were on the inside at the bottom of the headdress and shoulders.

 

Sphinx new j1.mdl

[Pitcher]

The library printed my Sphinx j model. Here are a few pictures. As you see, it still did not print perfectly, but I am happy with the result.  Thanks again to everyone who helped. Your ideas, illustrations, and video clips really taught me a lot.

 

 

 

 

[robcat2075]

Great to see that you got the pipeline working.

I wish my library had a 3D printer!

[Fuchur]

That looks pretty nice :). You are not happy with it?
Looks pretty solid to me... a little bit of a problem at the neck part, but still looks quite okay.

Best regards
*Fuchur*

 

[Pitcher]

Thanks!  I feel like I really learned a lot by doing the project, and I appreciate the help all of you gave during the process. I hope that reading this thread will also help others who might want to try 3-D printing.

 

[robcat2075]

To get a very smooth print you'd probably have to go to an SLS printer but it seems those are a pain and a half to work with.

[fae_alba]

Testors has a plastic filler that I use quite a bit. 3D printing is tough to get perfect every time, especially with smaller finer detail. Use the plastic filler, then lightly sand. Then a good coat of spray paint primer and paint. Also, 3D printers are sensitive to the environment they are in. If your printer is in an airconditioned room, or a draft, or even an open window, it will affect the quality of the print, since it wants a controlled temperature for the PLA. But, that being said, your print looks pretty damn good to me! Keep experimenting and have some fun with it.

[robcat2075]

There are numerous YouTubes about smoothing out  3D prints but they all seem to involve chemicals that will either give you cancer or blow your house up.

[Fuchur]

You can use chemicals for surface smoothing but especially for PLA that stuff is pretty toxic.

If you are after jewel like surface finishing you need to go with a SLA or SLP printer. FDM is better for robust stuff where the perfect finish is not needed that much.

Especially SLP printers are pretty affordable today but the build material is more expensive than for fdm printers (it is a resin so a little messier too). I am looking to get one in the near future.

best regards

*Fuchur*

 

 

[pixelplucker]

How big is the model and is it hollow?

SLA printers usually have the least noticeable steps. Most of even my tiniest prints are done at 50 micron and sometimes 25 micron. I could try to print it for ya

I have black resin I am using. I won't print a solid shape but if it is hollowed out I can give it a go and pop it in the mail for ya.

[robcat2075]

Here's a crazy  idea... model a character and print in a flexible material so you could put a stop motion armature in it.

[Fuchur]

6 hours ago, pixelplucker said:

How big is the model and is it hollow?

SLA printers usually have the least noticeable steps. Most of even my tiniest prints are done at 50 micron and sometimes 25 micron. I could try to print it for ya

I have black resin I am using. I won't print a solid shape but if it is hollowed out I can give it a go and pop it in the mail for ya.

At 25 micron I would say those steps are no longer really visible right? A very well printed 100 micron fdm layer height is already pretty hard to see/you have to focus on it to see it. I imagine at 4 times the resolution it should be pretty close to not visible with the eye only or am I wrong? 

[Pitcher]

I'll have to look for the Testor's plastic filler. That will probably do for my needs. I'm happy enough with the surface, generally, but there are a few places that had a glitch. Thanks for all the ideas.

[pixelplucker]

Depends on the resin and the uv inhibitors used along with if there are added pigments that can cause stepping to be more or less evident. Also dwell time is a factor. Dwell time is achieved by the lasers speed. Slower will increase dwell causing surrounding resin to expose or bloom beyond the lasers spot size. Trick is to use a balance on speed and intensity. Too fast the resin may not react in time, too intense may cause burning on the PDMS layer (clear rubber pad that the layers are formed on).