A finish discrepancy

Hi All,
This forum seems to have a bunch of level headed folks, so here goes my saga, which should really have just been a simple order...



I placed an order (which was essentially a re-order) for this skull in Polished Bronze steel. As you can see in the images, I had previously ordered this same model in Polished nickel steel. Both items I received are pictured. I can see in the polished nickel model that the hard edges of build layers are knocked down or 'burnished' as though the model were tumbled. I get that the process isn't a miracle and I can accept that this polished nickel part, while build layers are still discernable, is about as good as can be expected as far as tumble polishing.

Then I received this bronze colored part, which is uniformly textured and satin sheen at best, with completely intact edges to the build layers. I politely brought the lack of polish to Shapeway's attention, and after waiting a solid 6 days I'm being told production has deemed the two parts to have been polished identically, and there is no error. Respectfully, the tamest reaction I can garner is "WTF?!" Am I crazy? Does this look like a polished part to anybody else? And if so, what definition of "polished" is being used? Or, would you call this a raw bronze part?

I appreciate some more eyes on this concern, thanks.

For some extra clarification of the difference between polished and raw bronze steel, I offer these lovely examples from the community of polished bronze steel:



And, a model with the finish I received, identified as raw bronze steel:




It seems very clear that the layer edges on the polished models are softened, brighter, with almost a gold shine. It's not a great feeling to be flat out lied to in regards to whether or not a model was prepared correctly, and have no solution offered.

Yea I see a difference, those build lines look like straight off the machine. what the heck is that about? They saying the two look identical? I hate to even think about dealing with obstinate customer service, I've heard stories about Shapeways doing their damndest to avoid reprinting their own mistakes... good luck!!!

It probably took customer service a few days to inquire from their production partner whether their records show that the model spent the required time in the polishing tumbler. It does look like most of that time it may have ridden on top of the polishing media, but as at least the short description of the material on the model ordering page mentions "visible print lines" it may be within their quality limits, though certainly at the lower end. (And there is probably some selection bias in the comparison pictures you picked from the shop : If you were to offer your model for sale, which of the two images would you rather upload, and if you only ever received the raw-looking one, would you offer it for sale at all ?)

I gave Exone a link to this thread and also my contact information. If they reply to my email I'll foreword it here, but it would be cool if they posted an answer.

In my opinion the part is not sufficiently polished and needs a reprint.

Thanks for your efforts UniverseBecoming! Mkroeker, I'm ashamed to admit I got lost in the intent of your comparison bias point.

To clarify, I'm highlighting images of other folk's models which are polished bronze steel, as well as my first model which was polished nickel steel, and stating that the models when polished get the edges of the build layers knocked down, and those polished edges take on a brighter, more brassy hue. I believe that's evident in every picture I've seen of polished bronze models, though the effect is harder to distinguish on flat surfaces. I dont believe anybody in their right mind could post pictures of a model that looks like mine and call it a polished bronze finish.

If including the verbage "build layers will still be visible," is supposed to cover them in the event they send out completely unpolished models, that's pretty shady business. And frankly, if I was a subcontractor faced with reprinting a model I F-ed up, and Shapeways asked me if I had run it through the polisher for the correct amount of time, and there was no chance of repercussions, I'm pretty sure I'd find that my records showed it had.

Here's a detailed video of the model on YouTube. https://www.youtube.com/watch?v=Bp-Na9dGNmI Please let me know if you can see as even slight difference in shine from the most exposed edges to the deepest recesses.

I had issues with plating quality the past, particularly polished nickel plating not being very distinguishable from regular steel. And without a material testing service who knows what actually happened. But gold plating is generally more consistent and I stick with that because it's easier to see if it's been missed or swapped with something else. So basically I now stick with the matte gold finish for stuff I order. And if I see heavy print lines I convince myself they enhance the design, which at least can be true for fishing lures if not for objets d'art.

I wouldn't be so sure that people always get things right when they are posting photos and having them match materials in descriptions. This is particularly true for steel because the steel packaging does include the material process used, at least not in wording. It might be embedded in a bar code but it's easy for people to get that wrong, particularly if they don't get around to taking photos right away. I really wish they would add such info to the bags, or perhaps order numbers or other information so you can always backtrack to the My Orders page and verify such things. Anyway, just something to be aware of when citing other people's stuff.

I do believe that all of the examples I've included are indeed polished bronze steel. Shapeways doesn't offer any other bronze finishes besides 'raw' and a highly polished real bronze. No gold finish would be as dark.

Another exciting round of comparison, to show what, apparently, is Shapeways acceptable quality control range for polishing:

My point was that the tumbler polishing is a somewhat random process with inherently variable results, and as nobody is required to add actual product photos to their shop items it seems likely that most such photos will show near perfect parts that the designer was proud to showcase.
Have you sent these detail images to service as well ? From your initial description it sounds as if shapeways contacted ExOne (or whoever did the printing) with just "the customer says his part was not polished at all" and received a reply like "but our records show that it was tumbled".

I'm not really on anyone's side here. I'll give Shapeways the benefit of the doubt and assume that the printing process itself has high variability over time. In other words some prints come out of the infusion process with minor print steps and others come out with big stepping. So the issue may not be the "polishing" step because what would really be needed in some cases is "grinding" which is a more severe process to get to a very smooth surface. But that risks losing details on some models that people would also complain about so to some extent they are walking a tightrope here to make everyone joyously happy with their prints. But obviously things have been worded to allow prints to have some variability. I don't know what the solutions are here other than to hope for improvements at one or more points in the overall print/infusion process. Maybe they can add a process option to grind the heck out of pieces for an extra fee.

These aren't shop listing photos, it sounded like most of the images I referenced were the first prints these users received, in the "It Arrived!" section of the forum. Not the 'best of the best' from a large group over time. I think that if somebody ordered a polished model and gets one that looks identical to a raw model, and customer service refuses to admit an error, the designer wouldn't just suck it up and keep trying until they get one that looks like it's been through a polishing process. Service has seen plenty of evidence of the difference between the two models, and I can always send them a link to this thread, or the one on the RPF, or facebook, if they need further clarification.

I hear ya mrnibbles, but I must assume the build layer height hasn't changed over time, and that would be the only printing variable that would change the intensity of the stepping outside of a polish process. The problem is, knowing this is what they call polished, why the heck would anybody order it, as it looks exactly the same as a raw model? Maybe the extra process option they would charge for is to have somebody actually look at the models before they go out and determine whether they look like they've been polished, and if not, to put it (back?) in the tumbler until it comes out with some shine. Some places that's called quality control, and comes standard with your order.

My first skull with the nickel finish clearly went through a tumbler, and wasn't ground by hand. If I give you a rare rib roast and you complain, then i refuse to fix it because it verifiably spent 3 hours in an oven, whether or not the oven was warm, how likely are you to return to my establishment? All that needs to be done by Shapeways is to be sure that all 'polished' models go out with a similar level of wear, not by the number of minutes and seconds spent riding on top of media in a closed drum.

The issue could also be that bronze and nickel have different properties and hold up differently to polishing.

The photo of the raw bronze steel (bug) is clearly not shiney at all, where you're piece has shine, even though it's minimal.

I have an almost identical issue. I ordered a polished grey steel trilobite. The one I got isn't polished in the least. When I complained, I was told that the production team thought the metal wasn't strong enough to be able to handle being in the tumbler.

I am flabbergasted by their total lack of what customer service really is. WHY even offer something, if there is a good chance they won't be able to provide it, because they apparently only do one printing per order, and if yours doesn't come out right, oh well.

I am committed to letting anyone why might order from these people know exactly who they are dealing with. Their attitude seems to be "Hey, we sent you something that is approximately what you ordered, so suck it up.".

Here is a very basic chart showing some differences in metal strengths.

http://www.azahner.com/images/metal-hardness.jpg

Can't disagree on your last point so far kjham9. If they couldn't put your model in the tumbler, they should have caught it early enough to alert you and give you the option of canceling or modifying the order. Some good places to spread the word about your experience include Facebook, Youtube, the RPF, 3dprintboard.com, 3dhubs talk forum, and 3dprintingforum.org.

jimmycrackzcornz, thanks for the science, but both models are exactly the same metal. The bronze and nickel are both superficial layers after the polish step. Having the model in hand, I will politely disagree that my model has more shine than the bug example. Any shine evident would be from the metallic powder in the coating. A shine from a polish step would be lesser in the most recessed areas, and mine is 100% uniformly satin.

There are no rockstars at Shapeways that can remedy a simple situation like this? Somehow I get the impression there's been a company wide memo to the effect of "Hey, we're getting way too many rejects from this one supplier, this is an official moratorium on reprints or refunds for unpolished models. Whatever it looks like, you will tell them it's within our acceptable range, end of story. Management apologizes in advance for your credibility"

Yeah, in one of the emails I got from Shapeways, they said that they have a disclaimer on their metals page that says they can't always polish certain kinds of metals. I wasn't able to easily find their metals page, and my feeling is that any such disclaimer should have been in big, red letters on the order page itself.|

Honestly, I wasn't really pissed off about it until I started getting their responses. My initial feeling was "Whoops, they sent me the wrong item.". Then, I started getting all their excuses and it made me mad. (Although I have to say, in all fairness, that they DID credit me back the S&H for the item.)

I just think their customer service is really, really poor. And I agree with you, Logan74k: they should have caught it early and given me the option of continuing or cancelling.

Hey logan74k,

We hear you loud and clear on this and are looking into it. Someone in CS will reach out to you shortly.

offhand, it looks like one of these models was beadblasted and the other tumbled to finish. I am not sure what caused the discrepancy but once we investigate internally we'll have more answers.

Hey logan74k,

I am going to reach out to you via your customer service email thread so that we can chat and work on this together.

Thanks for the messages Nisey and Andrewsimonthomas. I look forward to hearing what a second glance turns up in terms of a resolution.

Meantime, jimmycrackzcornz's perception of a modicum of shine on this dark bronze model suggests I probably could have done a better job of lighting my images properly to emphasize the difference, so here are a few more, along with the previous image of the verified raw bronze bug.

it is a very nice piece. I hope you can find a solution.