Need suggestions on best orientation for this object

Printing a christmas ornament in clear at 25 microns. Should take about 16 hours. AND, I will need to eventually do 12 of them (1 for each grandchild), each with their names on them. Needless to say, I don’t have a lot of time for experimentation. After a successful first print, I hope to print 3 or 4 at a time.

So, I am asking for input about the optimal orientation for this. I prefer to have few or no interior supports, but the final closed portion at top may require it. Your opinions welcomed. Obviously, a failed print 13 or so hours into the job would be VERY disappointing.

Ideally, I will start a run tomorrow (12/12) evening, so quick responses are greatly appreciated.

Thanks in advance for your help.

Here is the .form file and a link to the STL file

Hello Twehr,

I’ve reviewed your custom Christmas ornament and I believe it’s going to look like a beauty when it’s complete. I’m not sure how big you with to print it, but when I downloaded your .form file, I believe it you would be hard pressed to print 2 of these ornaments at a time as they seem to be quite large (~80x80x115mm). If you scaled it down, you might be able to get 3 or 4 at once, but that would be about it.

In regards to orientation, I would suggest printing it in its normal upright position as the material appears to be naturally building upon itself which is ideal for 3D printing with minimal supports. You could either print it as is or since the first several layers are typically condensed (or compressed), you may want to have it built with supports directly underneath the base. Be careful not to use internal supports for this ornament because it will be difficult if not near impossible to remove them afterward. Because of its geometry, it makes a natural print upright just as it is. You may also want to slightly relocate the supports underneath the name tag just to avoid any supports in an undesirable area cosmetically speaking.

I’ve set it up using a support density of 0.50 and point size of 0.40 mm, but remember to uncheck the “internal supports”.

You may not have to use a 25-micron layer resolution because I think a 50 or even a 100 micron will suffice which will drastically reduce your print time for each print. If you want a really clear finish on it, I would suggest using a couple of very fine coats of a “Clear Glaze” spray lacquer (like Krylon Clear Glaze). It gives an amazing finish quality which will make your ornament see-thru like a glass.

Hope these tips help as I love to use my Formlabs Form 2 printer for amazing quality prints. Cheers!

Thank you, Wolffe. I agree with everything you said.

I designed it with the hope that it would build upon itself, but wanted some confirmation before starting a long test. Yes, I think it will be pretty. And yes, I will be clear coating it. Keeping all the supports at the bottom will help with cleanup, that’s why I designed the solid bottom. To ake it easier to do.

I chose 25 microns specifically because of the lettering, which needs to be sharp. Do you think it will hold up at 100? I also thought it would build on itself more reliably at 25, but sounds like you may be saying that is not true.

I planned to shrink it down to 70 x 70 to fit 4 on the platform.

I will be doing a new design each year, each personalized with the kids names and the year. At current count that is 12 for grandkids and 1 for the great grandchild. Hopefully I can get enough years in to give them each something to keep after I am gone :confounded:.

Thanks again for your thoughts.

I agree with @Wolffe entirely. I too think 50 microns should be sufficient and cut down your print time dramatically. I was able to get 4 of them to print when I resized to 90% (just barely…it is going to be a tough fit even then).

With a few of my clear prints, I’ve sanded with 100 grit sand paper all the way down to 1200. My final steps were wet sanding 1200 with mineral oil, and then the Krylon. Amazing results!

If you’re going to resize down to 70x70, I’d try a test print first at 100 as you’d be surprised how well the resolution turns out. If necessary, move down to 50 microns. You may want to add an external support just below the top “cone” to support it as its being built, but Preform seems to like it as is. The problem with printing at 25 or 50 microns is the beginning layers (at that level) will become somewhat weak for the first few layers before it becomes strong enough to withstand the peeling process. At 100 microns, each layer is at 0.1 mm which is already quite thin.

Since it going to all clear when it’s done, you may want to figure out if somehow applying a color (like an indelible pen for example) to write across the lettering before you clear coat it. The only difference at 25 microns will be that the surface will be that much smoother, but if you clear coat it, it will fill in all the gaps from printing anyways, so it may not be necessary. Don’t forget that every time you downsize the print resolution, you more or less double the print time. At 90% original size, the lettering appears to be about 10-15 cm high, which may only be visible up close anyways, especially since it going to be clear. Perhaps a color topping on the letters would help make them stand out before you clear coat to shine it up and seal in the lettering color.

Just curious, what 3D software are you using?

I’ll try the 100 first and see how it turns out. Yes, the lettering is quite small, but it is more for personalization than for display. But I do want it very legible. I do want to “color” the lettering top surface - but that will be experimentation with methods. Will report back on any success I have with it.

I will be sanding and polishing (100,300, 600, 1200) to eliminate any support marks before clear coating with the Krylon. If they are all on the bottom, should be pretty easy to do.

As to software - I am forcing myself to learn Fusion 360. I tried Fusion about 5 or 6 years ago when it was newer and less capable and wasn’t all that impressed. Mostly I have used (Alibre) Designer, which was subsequently purchased by 3dSystems. I have always used it to design my other CNC equipment (Routers, Lasers, etc.). But I think Fusion has now matured to the point where it may be the better long-term product for me to use. I love everything that it CAN do - but it is taking me time to THINK in Fusion instead of DESIGNER. So designing the ornament took a lot of time. As I get more comfortable with it, I will be converting all my old equipment designs to Fusion as well, and then will live entirely in that world going forward.

Appreciate everyone’s input today. I’ll post photos when I get a print out.

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Ah, another Alibre user. I love Alibre (well now Geomagic Deisgn…) I really wish 3D Systems would spend some time and money updating and improving it. I have used Fusion 360. I have been reluctant to move to it and force myself to learn it.

Yeah - I am pretty comfortable with Alibre. But it costs $300 for every upgrade, and I don’t think it has been upgraded for 2 or 3 years now. Fusion has really matured and is truly a complete package, modeling, sculpting, drawing, CAM, rendering, etc. And it seems they have almost monthly updates. One of the big pluses is the huge amount of support videos, both from the company and from the user-community. I have watched over 75 videos on Fusion 360 and learned something from every one of them. For me, it is just a matter of forcing myself to practice using all the power (both simple as well as advanced) that Fusion 360 has.

I ran the test print last night - shrinking it to 70mm diameter and printing at 100 microns. Overall, I am happy with it, but there are a couple of things…

  1. Though it is hard to see in the attached photo, I think the 100 microns is a bit thick for my taste on this project. I don’t care to see the layers and you don’t have to look too closely to see them. (Photo does not show it well.) I think 50 will do the trick for me and printing 4 at a time, 8-10 hours is acceptable.

  2. There was one small failure with the print, shown in the attached image. Looks like 1 layer of one of the elements slid. I don’t think it was caused by any aspect of the design, nor the setup/orientation/supports. It just happened.Everything else on the same layer is perfect. In fact all layers of this ornament appear to be perfect.

So, here is my plan. I will shrink this down even further - maybe 50mm diameter and run one more test print at 50 microns tonight. If everything is good with that, I will swap out the names on a dozen more copies and start running them tomorrow. I’ll play with this first test (and the second one) to see what works for coloring the lettering and applying the finish.

The attached image shows the flawed layer area. The photo was taken after 2nd IPA bath so I was being careful about handling and couldn’t get a better photo. It is in the cure box now. I’ll try to get better pictures tonight, both of the flaw and the overall.

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Update…

I have printed all 12 ornaments (scaled to 55 mm and printed 5 at a time) and the print quality is fine at .5 but I have certainly had issues with the finishing.

The first (test) print, I used my standard 10 min IPA, 10 min IPA, and 1 hr in by cure box at 60 degrees. The result (see image) was a very hazy finish overall. Certainly not the crystal look I hoped for. I did try polishing with 100…1200 grit, but that really did not help. I think it is because, being hollow, the inner sides of the piece are also hazy. There is no way to get inside to polish that away.

I already had a new 10L ultrasonic cleaner on order and it arrived. And I had on hand a couple gallons of Yellow Magic 7, which I use for cleaning tanks, etc. I tried that in the YM7 for 10 minutes in the ultrasonic at 40 degrees. It certainly cleaned the resin off nicely. But trying to wash away the yellow was very hard. Again, mostly because of the hollow nature of the ornament. So it, too, turned out hazy. (No photo, but similar to above.)

Ultimately, I choose to clean with IPA and then spray a silver sparkle over all. The ornaments look fine (see sample below), but are certainly not what I originally hoped for.

BTW - the lettering was painted with a 1mm paint pen. Works very nicely.

So I am still in search of a method of producing crystal clear objects. Don’t know if I am doing something terribly wrong (believe me, a very real possibility), or is it just the existence of visible but impossible to get to interior surfaces that is causing the issue.

I really love the look of clear coming out of the printer, but don’t know how to maintain that look through the cleanup and cure processes. Any additional comments or advice will be greatly appreciated.

I certainly didn’t think about the inside, and you are probably right. I have printed some very thin cone/cylinder items where it was impossible to sand/polish the inside and I had the same disappointment as you did. I suppose you could have split your model vertically down the middle, polished the inside and then joined and it may have had better results. But hind sight is 20/20

Thanks for the confirmation that my theory has merit. Since this was my first use of Clear, I had no experience with it to go on.

I think I will do some tests with other shapes that do not require interior attention and see how the ultrasonic works. That should make it easier to clean the YM7 and then see what it looks like.

How are you removing the resin from your clear prints?

My method is as follows:

Right off the printer I do two 20min baths in 99% IPA. I then rinse under water and scrub softly with a soft bristled brush. Then its back into the IPA for another 10-15min bath, water, dry, then cure chamber. (make sure it is dry before you cure…else you will get spots!)

I then proceed with the sanding. If i want a very clear finish I proceed with the various grits of sand paper and then krylon. If it is not needed for prototyping purposes i will sand the supports off with 100, then 800 grit and that’s it.

I’m finding that everyone has a slightly different way of doing things. Just like in Texas if you ask 100 people for their Chili recipe, you will get 100 different recipes! :slight_smile:

a very quick way of producing clear objects is as follows- coat the object in clear resin by using a clean cloth (or finger!). Then expose to UV light, youll need to rinse in ipa after, but comes out very good.
If you want the optical quality without distortion, then youll need to rub down an polish, however coating in resin gives a very good result.

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