Content of stainless steel sealant?

Hi there.

Recently, a customer with a baby asked me about the safety of a necklace pendant she was considering in either stainless steel regular or antique bronze finish. I read the Shapeways terms and conditions and I know that the models are not to be "given to children." This is not for a child, so I'm not concerned about it as a choking hazard. But as it may wind up in a baby's mouth, I am concerned about toxicity and lead content of the finishes, both out of ethical considerations and because I may have some legal obligation to disclose the contents, since I'm advertising the product as stainless steel and my customers may not realize there is any coating on them. I've read in the forums that there is no lead or anything toxic remaining from the stainless steel printing process (please chime in if you have another perspective). I've also read here that there is a clear sealant put on the stainless steel items, presumably to inhibit corrosion.

1. What is this sealant and what's in it? Is it toxic? Relatedly, if I do any post-production work (filing, sanding, taking off sprues), should I worry about the surface finish becoming inconsistent, or the surface or the surface wearing unevenly?

2. Is this sealant also on silver items?

3. What is in the antique bronze finish made of, and is there any toxic or lead residue?

I realize that the items are not food safe, but I think this is a separate question of whether they're toxic. I have read through the forums so I know that there are individuals whose kids have eaten these things without consequence, but I really want to know the actual content of what I'm selling. Given all the materials info/datasheets, I'm surprised that Shapeways has not specified these things.

Thanks for reading/responding!
Melissa

Where did you read or see about a coating? I wasn't aware of a coating. I do know that some people have a reaction to the bronze. I'll ask Nancy about any other elements in the process that could be harmful, but besides allergies to the metals I haven't seen or heard of any other issues.

Robert's comment:

https://www.shapeways.com/forum/index.php?t=msg&&th=1 750&goto=8440#msg_8440

GlenG is the person you want to talk to about steel/bronze parts. Better, SW should interview him about all the details he keeps repeating over and over (tapping, soldering, rusting, coating, bevels/fillets, etc), and put them in a centralised place.

Other forums allow searching in the posts of a given user but not this one, and current system seems to ignore the "by user" search option too... so maybe send him a PM if you are in a hurry.

Cool. I hope that he responds to this thread. An interview would also be terrific!

I did read through the forums before posting this, and saw bits and pieces of information in different threads as they pertained to specific questions. Even just sharing the names of the clear coat product (and which prints it's used on) and antiquing agent would allow me to do my own due diligence.

Thanks again.

Melissa and all,
No lead in any form is contained in a finished stainless print from SW.
The "antique bronze" finish is produced simply by heating a finished part to 300 degree C. it's a heat patina and no chemicals are used.
All SS parts receive a light protective coat of clear lacquer before being shipped out. One of two types are used. On polished finishes it would be: "#2105 Clear Lacquer" from the G.J. Nikolas Co. the can says; " Non-Toxic When Dry"
On matte finished parts it would be: "Incralac" which is a clear acrylic based finish for use on copper alloys. This is inert as far as skin contact goes but I'm not sure about ingestion of the dry film.

As far as babies putting metal objects in their mouths. On it's own this sounds like a scenario to avoid. But this is more about the physical danger rather than any chemical hazard.

Hope this helps,
-G

Terrific. Thanks so much for the insightful reply!

Do you have any input on the question of whether the surface will look inconsistent (or weather inconsistently) if part of the surface has been reworked (I'm thinking specifically of filing down spots after cutting off sprues). I know some people, especially with rings, have had rust issues and I wonder how the lacquer affects this.

The SS print medium is consistant throughout it's mass. Any "reworking" of the surface will not change it's characteristics however you should probably re-apply these items with some form of protective coating, especially things worn close to the skin, like rings. The SS media, in it's bare condition, is reactive to moisture and skin oils. Nothing toxic, but some people can/will have skin issues (dermititis) wearing this bare metal next to the skin.
The acrylic coatings I have mentioned work quite well but there are other products that should work just as well. Just understand than no coating will last forever and some periodic maintenance should be expected. The schedule for this is impossible to predict because so much depends on the end user.
-G

Great.

Thanks again for following up.