How to seal nylon ?
How to seal nylon ?
(OP)
Hello,
We would like to use nylon to hold ink. This is part of a pen that is being 3d printed in nylon 12.
Is there a post production technique that we could use to stop the nylon absorbing the ink ?
Thanks for any pointers !
We would like to use nylon to hold ink. This is part of a pen that is being 3d printed in nylon 12.
Is there a post production technique that we could use to stop the nylon absorbing the ink ?
Thanks for any pointers !






RE: How to seal nylon ?
2. If not 1, are you using water-based ink? Nylon likes to absorb water. Try conditioning the nylon (soak in water for 8-24 hours, then air dry) before filling with ink.
RE: How to seal nylon ?
The surface is porous and the ink does soak into the gross porosity. It would be great to find a coating but I have not had any luck up until now. The ink reservoir would need to be coated using a dipping process I think.
Conditioning the nylon is certainly a good point - thanks. But I think I will still need to find a coating of some sort.
RE: How to seal nylon ?
RE: How to seal nylon ?
I've stumbled across information related to "stain blockers for nylon" These techniques are widely use din the carpet industry.
I wonder if teflon could be applied to create a protective layer. Teflon One Coat coud perhaps work ?
RE: How to seal nylon ?
I have used that in the past. Standard materials for that process are ABS and polycarbonate.
Chris DeArmitt PhD FRSC CChem
RE: How to seal nylon ?
On another project I got a quote from Stratasys (a few days ago) using FDM that was about 4 times higher than the quote from Shapeways using SLS.
But thanks for the suggestion.
RE: How to seal nylon ?
"But I am not aware of any 3D printing service offering other treatments"
Stratasys, quickparts, protomold, all offer sealing on their 3d printed parts. I thought...maybe its only for the SLA models. I will grant you that different technologies and substrates will react differently (and probably need different formulas) to different sealers.
The following all talk about it, but none of them have any specific suggestions beyond paints and coatings available in typical hardware stores:
http://ww
http://dig
www.cs.berkeley.edu/~sequin/TALKS/SIGG03_RP2.ppt
I'd start with a thinned urethane varnish, and move up to a thinned acrylic paint if needed. Find finishes that use solvents that aren't included in your ink formula, would be my parting suggestion.
RE: How to seal nylon ?
There are chemicals that will compete with the dyestuff and block the dye sites in the nylon. This is used at times in wool nylon carpets to help the wool and the nylon to take the dye to the same extent and match each other when dyed in the same bath. I forget their name, but dyestuff companies should be able to help.
I am not quite sure of your design and the part that is nylon.
Do you have an ink tank that is nylon then you print that, or do you have a tank that does not stain from the ink, then you print that with a nylon based ink to print on the tank, then that nylon based ink absorbs other colours from the ink in the tank.
Regards
Pat
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RE: How to seal nylon ?
The entire ink tank (including the structure of the tank) is 3D printed in nylon.
What do you think about a teflon coating - would that bond well to the nylon ?
Regards,
Mark
RE: How to seal nylon ?
Teflon will not stick, but you might be able to mix PTEF fine powder into the nylon before it is printed. I am a bit out of date on what's available and what form the resin is in before printing the part.
You might improve the part by flame polishing.
You might improve it by painting with a clear 2 pack polyester. You will probably need a primer specifically for nylon to get good adhesion.
Why nylon. Nylons absorb colours and stain easily.
Regards
Pat
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RE: How to seal nylon ?
The particular type of 3D printing we are looking into is SLS where very small particles are laser sintered.
Nylon would be ideal in terms of cost vs print detail.
Regarding the PTEF I was wondering about baking Teflon S (there are low bake temperature variants)
Regards,
Mark
RE: How to seal nylon ?
RE: How to seal nylon ?
Regards
Pat
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RE: How to seal nylon ?
RE: How to seal nylon ?
The problem of staining raised by Pat calmed my enthusiasm for the urethane.
I found a paper discussing coating nylon substrates by sol-gel I'll mention it here for completeness h
It is surprising to find so few coating solutions for a material that has been around for so long !
RE: How to seal nylon ?
Re the staining of various materials, it will vary, depending on the nature of the colourants. My comments re dyes and stains are generalised. Results with specific colourants may vary from the general trend. Without going into details, it depends on the existence of particular chemical groups and polarity in the molecules of each and on pore sizes in the polymer.
Regards
Pat
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RE: How to seal nylon ?
But, at the root, making an ink container via an inherently porous process should perhaps be reconsidered.
BTW, I made some really cool containers out of some scrap nylon tubing...using commercial "RIT" dye to color it.
RE: How to seal nylon ?
RE: How to seal nylon ?
Pat, if you wouldn't mind, I'd like to understand why the Teflon S is not suitable. It seems teflon is used as a post-treatment for nylon carpets e.g. http://www.baneclene.com/catalog/teflon.html In this case it does get removed during industrial cleaning. In our application the coating is not subjected to significant abrasion - it is the chemical resistance that we need. But if the teflon is baked on I imagine that would make a much more permanent bond ?
Regards,
Mark
RE: How to seal nylon ?
"The B-45 and B-482 are possibilities. You mentioned that the reservoir might need to be dipped; the two epoxies are simular viscosity to honey, which makes it fairly easy to pour into a container and dip your parts in to coat.
However, surface prep on the nylon may be required to increase surface energy and create a stronger bond. We recommend abrading the surfaces with 100-120 grit sandpaper and clean with isopropyl alcohol. Ideally, the adhesive coating should fall between .004'-.007' thick over the nylon, to ensure a good cross-link. Average cure time is 24-36 hours at ambient. "
RelTek get huge credit in my book for answering so effectively.
This is looking close to a viable solution.
RE: How to seal nylon ?
Chris DeArmitt PhD FRSC CChem